Through thickness property variations in a thick plate AA7050 friction stir welded joint

International Nuclear Information System (INIS)

Canaday, Clinton T.; Moore, Matthew A.; Tang, Wei; Reynolds, A.P.

2013-01-01

In this study, moderately thick (32 mm) AA7050 plates were joined by friction stir welding (FSW). Various methods were used to characterize the welded joints, including nugget grain size measurements at different locations through the thickness, micro-hardness indentation through nugget, thermo-mechanically affected zone (TMAZ), and heat affected zone (HAZ) at different cross section heights, and residual stress measurement using the cut compliance method with full thickness and partial thickness specimens. All testing results are consistent with the presence of a strong gradient in peak temperature through the plate thickness during FSW.

Thickness, Composition and Physical Properties of Crust in Iceland's Neovolcanic Zone

Science.gov (United States)

Kelley, D. F.; Barton, M.

2005-12-01

We report the results of an ongoing effort to use petrologic data to estimate the thickness, composition and physical properties of crust in the neovolcanic zone of Iceland. The objectives are to constrain the depths of magma chambers, calculate geothermal gradients, and resolve discrepancies in the interpretation of geophysical data (primarily gravity and seismic). 1788 whole rock analyses and 170 glass analyses of erupted Icelandic lavas from the neovolcanic zone have been compiled from published papers. Variation diagrams indicate that Icelandic magmas evolved primarily by crystallization of Ol-Cpx-Plag, whereas the most primitive magmas evolved by crystallization of Ol alone. Phase equilibrium constraints were used to quantitatively estimate the pressure of crystallization along the Ol-Cpx-Plag cotectic and hence the depths of the magma chambers. The latter occur at 20±6.2 km, and the average temperature of magma in the chambers is 1207±26°C (also estimated from phase equilibrium constraints). The results suggest magma chambers located at the base of the crust indicating that the latter is ~20 km thick along the neovolcanic zone in agreement with estimates based on geophysical studies. It is argued that the average composition of erupted lavas provides an accurate estimate of crustal composition because magma evolution occurs in sub-crustal chambers. A representative geothermal gradient was calculated using the average crust composition and surface heat flow measurements. The calculated gradient is consistent with the periodic presence of shallow intracrustal magma chambers at ~5 km depth that have been detected seismically, with hydrothermal circulation in the uppermost 3 km of the crust, and with temperatures of ~1200°C at the base of the crust. The geotherm was used to calculate a density-depth profile for average crust. Densities decrease with depth if a low-pressure mineralogy is used for the crust. This density inversion can be avoided by assuming

Soft and Hard Tissue Changes Following Immediate Placement or Immediate Restoration of Single-Tooth Implants in the Esthetic Zone: A Systematic Review and Meta-Analysis.

Science.gov (United States)

Yan, Qi; Xiao, Li-Qun; Su, Mei-Ying; Mei, Yan; Shi, Bin

.18 mm; 95% CI: -0.00 to 0.37 mm), the papillae level of the distal site (SMD = -0.12 mm; 95% CI: -0.34 to 0.09 mm), and the midbuccal mucosa (SMD = -0.22 mm; 95% CI: -1.29 to 0.85 mm). Within the limitations, it can be concluded that immediately placed, restored, or loaded single-tooth implants in the esthetic zone result in similar hard and soft tissue changes compared with conventional protocols.

In vivo evaluation of immediately loaded stainless steel and titanium orthodontic screws in a growing bone.

Directory of Open Access Journals (Sweden)

Kerstin Gritsch

Full Text Available The present work intends to evaluate the use of immediate loaded orthodontic screws in a growing model, and to study the specific bone response. Thirty-two screws (half of stainless steel and half of titanium were inserted in the alveolar bone of 8 growing pigs. The devices were immediately loaded with a 100 g orthodontic force. Two loading periods were assessed: 4 and 12 weeks. Both systems of screws were clinically assessed. Histological observations and histomorphometric analysis evaluated the percent of "bone-to-implant contact" and static and dynamic bone parameters in the vicinity of the devices (test zone and in a bone area located 1.5 cm posterior to the devices (control zone. Both systems exhibit similar responses for the survival rate; 87.5% and 81.3% for stainless steel and titanium respectively (p = 0.64; 4-week period, and 62.5% and 50.0% for stainless steel and titanium respectively (p = 0.09; 12-week period. No significant differences between the devices were found regarding the percent of "bone-to-implant contact" (p = 0.1 or the static and dynamic bone parameters. However, the 5% threshold of "bone-to-implant contact" was obtained after 4 weeks with the stainless steel devices, leading to increased survival rate values. Bone in the vicinity of the miniscrew implants showed evidence of a significant increase in bone trabecular thickness when compared to bone in the control zone (p = 0.05. In our study, it is likely that increased trabecular thickness is a way for low density bone to respond to the stress induced by loading.

In vivo evaluation of immediately loaded stainless steel and titanium orthodontic screws in a growing bone.

Science.gov (United States)

Gritsch, Kerstin; Laroche, Norbert; Bonnet, Jeanne-Marie; Exbrayat, Patrick; Morgon, Laurent; Rabilloud, Muriel; Grosgogeat, Brigitte

2013-01-01

The present work intends to evaluate the use of immediate loaded orthodontic screws in a growing model, and to study the specific bone response. Thirty-two screws (half of stainless steel and half of titanium) were inserted in the alveolar bone of 8 growing pigs. The devices were immediately loaded with a 100 g orthodontic force. Two loading periods were assessed: 4 and 12 weeks. Both systems of screws were clinically assessed. Histological observations and histomorphometric analysis evaluated the percent of "bone-to-implant contact" and static and dynamic bone parameters in the vicinity of the devices (test zone) and in a bone area located 1.5 cm posterior to the devices (control zone). Both systems exhibit similar responses for the survival rate; 87.5% and 81.3% for stainless steel and titanium respectively (p = 0.64; 4-week period), and 62.5% and 50.0% for stainless steel and titanium respectively (p = 0.09; 12-week period). No significant differences between the devices were found regarding the percent of "bone-to-implant contact" (p = 0.1) or the static and dynamic bone parameters. However, the 5% threshold of "bone-to-implant contact" was obtained after 4 weeks with the stainless steel devices, leading to increased survival rate values. Bone in the vicinity of the miniscrew implants showed evidence of a significant increase in bone trabecular thickness when compared to bone in the control zone (p = 0.05). In our study, it is likely that increased trabecular thickness is a way for low density bone to respond to the stress induced by loading.

Refracted arrival waves in a zone of silence from a finite thickness mixing layer.

Science.gov (United States)

Suzuki, Takao; Lele, Sanjiva K

2002-02-01

Refracted arrival waves which propagate in the zone of silence of a finite thickness mixing layer are analyzed using geometrical acoustics in two dimensions. Here, two simplifying assumptions are made: (i) the mean flow field is transversely sheared, and (ii) the mean velocity and temperature profiles approach the free-stream conditions exponentially. Under these assumptions, ray trajectories are analytically solved, and a formula for acoustic pressure amplitude in the far field is derived in the high-frequency limit. This formula is compared with the existing theory based on a vortex sheet corresponding to the low-frequency limit. The analysis covers the dependence on the Mach number as well as on the temperature ratio. The results show that both limits have some qualitative similarities, but the amplitude in the zone of silence at high frequencies is proportional to omega(-1/2), while that at low frequencies is proportional to omega(-3/2), omega being the angular frequency of the source.

Immediate placement and provisionalization of maxillary anterior single implant with guided bone regeneration, connective tissue graft, and coronally positioned flap procedures.

Science.gov (United States)

Waki, Tomonori; Kan, Joseph Y K

2016-01-01

Immediate implant placement and provisionalization in the esthetic zone have been documented with success. The benefit of immediate implant placement and provisionalization is the preservation of papillary mucosa. However, in cases with osseous defects presenting on the facial bony plate, immediate implant placement procedures have resulted in facial gingival recession. Subepithelial connective tissue grafts for immediate implant placement and provisionalization procedures have been reported with a good esthetic outcome. Biotype conversion around implants with subepithelial connective tissue grafts have been advocated, and the resulting tissues appear to be more resistant to recession. The dimensions of peri-implant mucosa in a thick biotype were significantly greater than in a thin biotype. Connective tissue graft with coronally positioned flap procedures on natural teeth has also been documented with success. This article describes a technique combining immediate implant placement, provisionalization, guided bone regeneration (GBR), connective tissue graft, and a coronally positioned flap in order to achieve more stable peri-implant tissue in facial osseous defect situations.

76 FR 70342 - Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, Drawbridge Operation...

Science.gov (United States)

2011-11-14

...] Quarterly Listings; Safety Zones, Security Zones, Special Local Regulations, Drawbridge Operation... published in the Federal Register. This notice lists temporary safety zones, security zones, special local... Commanders and Captains of the Port (COTP) must be immediately responsive to the safety and security needs...

Land surface temperature as an indicator of the unsaturated zone thickness: A remote sensing approach in the Atacama Desert.

Science.gov (United States)

Urqueta, Harry; Jódar, Jorge; Herrera, Christian; Wilke, Hans-G; Medina, Agustín; Urrutia, Javier; Custodio, Emilio; Rodríguez, Jazna

2018-01-15

Land surface temperature (LST) seems to be related to the temperature of shallow aquifers and the unsaturated zone thickness (∆Z uz ). That relationship is valid when the study area fulfils certain characteristics: a) there should be no downward moisture fluxes in an unsaturated zone, b) the soil composition in terms of both, the different horizon materials and their corresponding thermal and hydraulic properties, must be as homogeneous and isotropic as possible, c) flat and regular topography, and d) steady state groundwater temperature with a spatially homogeneous temperature distribution. A night time Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) image and temperature field measurements are used to test the validity of the relationship between LST and ∆Z uz at the Pampa del Tamarugal, which is located in the Atacama Desert (Chile) and meets the above required conditions. The results indicate that there is a relation between the land surface temperature and the unsaturated zone thickness in the study area. Moreover, the field measurements of soil temperature indicate that shallow aquifers dampen both the daily and the seasonal amplitude of the temperature oscillation generated by the local climate conditions. Despite empirically observing the relationship between the LST and ∆Z uz in the study zone, such a relationship cannot be applied to directly estimate ∆Z uz using temperatures from nighttime thermal satellite images. To this end, it is necessary to consider the soil thermal properties, the soil surface roughness and the unseen water and moisture fluxes (e.g., capillarity and evaporation) that typically occur in the subsurface. Copyright © 2017 Elsevier B.V. All rights reserved.

Treatment outcome of immediate, early and conventional single-tooth implants in the aesthetic zone : a systematic review to survival, bone level, soft-tissue, aesthetics and patient satisfaction

NARCIS (Netherlands)

den Hartog, Laurens; Huddleston Slater, James J. R.; Vissink, Arjan; Meijer, Henny J. A.; Raghoebar, Gerry M.

2008-01-01

den Hartog L, Huddleston Slater JJR, Vissink A, Meijer HJA, Raghoebar GM. Treatment outcome of immediate, early and conventional single-tooth implants in the aesthetic zone: a systematic review to survival, bone level, soft-tissue, aesthetics and patient satisfaction. J Clin Periodontol 2008; 35:

Nearshore sediment thickness, Fire Island, New York

Science.gov (United States)

Locker, Stanley D.; Miselis, Jennifer L.; Buster, Noreen A.; Hapke, Cheryl J.; Wadman, Heidi M.; McNinch, Jesse E.; Forde, Arnell S.; Stalk, Chelsea A.

2017-04-03

Investigations of coastal change at Fire Island, New York (N.Y.), sought to characterize sediment budgets and determine geologic framework controls on coastal processes. Nearshore sediment thickness is critical for assessing coastal system sediment availability, but it is largely unquantified due to the difficulty of conducting geological or geophysical surveys across the nearshore. This study used an amphibious vessel to acquire chirp subbottom profiles. These profiles were used to characterize nearshore geology and provide an assessment of nearshore sediment volume. Two resulting sediment-thickness maps are provided: total Holocene sediment thickness and the thickness of the active shoreface. The Holocene sediment section represents deposition above the maximum flooding surface that is related to the most recent marine transgression. The active shoreface section is the uppermost Holocene sediment, which is interpreted to represent the portion of the shoreface thought to contribute to present and future coastal behavior. The sediment distribution patterns correspond to previously defined zones of erosion, accretion, and stability along the island, demonstrating the importance of sediment availability in the coastal response to storms and seasonal variability. The eastern zone has a thin nearshore sediment thickness, except for an ebb-tidal deposit at the wilderness breach caused by Hurricane Sandy. Thicker sediment is found along a central zone that includes shoreface-attached sand ridges, which is consistent with a stable or accretional coastline in this area. The thickest overall Holocene section is found in the western zone of the study, where a thicker lower section of Holocene sediment appears related to the westward migration of Fire Island Inlet over several hundred years.

Aquifer recharge with stormwater runoff in urban areas: Influence of vadose zone thickness on nutrient and bacterial transfers from the surface of infiltration basins to groundwater.

Science.gov (United States)

Voisin, Jérémy; Cournoyer, Benoit; Vienney, Antonin; Mermillod-Blondin, Florian

2018-05-16

Stormwater infiltration systems (SIS) have been built in urban areas to reduce the environmental impacts of stormwater runoff. Infiltration basins allow the transfer of stormwater runoff to aquifers but their abilities to retain contaminants depend on vadose zone properties. This study assessed the influence of vadose zone thickness (VZT) on the transfer of inorganic nutrients (PO 4 3- , NO 3 - , NH 4 + ), dissolved organic carbon (total -DOC- and biodegradable -BDOC-) and bacteria. A field experiment was conducted on three SIS with a thin vadose zone (zone (>10 m). Water samples were collected at three times during a rainy period of 10 days in each infiltration basin (stormwater runoff), in the aquifer impacted by infiltration (impacted groundwater) and in the same aquifer but upstream of the infiltration area (non-impacted groundwater). Inorganic nutrients, organic matter, and dissolved oxygen (DO) were measured on all water samples. Bacterial community structures were investigated on water samples through a next-generation sequencing (NGS) scheme of 16S rRNA gene amplicons (V5-V6). The concentrations of DO and phosphate measured in SIS-impacted groundwaters were significantly influenced by VZT due to distinct biogeochemical processes occurring in the vadose zone. DOC and BDOC were efficiently retained in the vadose zone, regardless of its thickness. Bacterial transfers to the aquifer were overall low, but data obtained on day 10 indicated a significant bacterial transfer in SIS with a thin vadose zone. Water transit time and water saturation of the vadose zone were found important parameters for bacterial transfers. Most bacterial taxa (>60%) from impacted groundwaters were not detected in stormwater runoff and in non-impacted groundwaters, indicating that groundwater bacterial communities were significantly modified by processes associated with infiltration (remobilization of bacteria from vadose zone and/or species sorting). Copyright © 2018 Elsevier B

The Dermal Apron Technique for Immediate Implant Socket Management: A Novel Technique.

Science.gov (United States)

Levin, Barry P

2016-01-01

With immediate implant placement and provisionalization (IIP) in the esthetic zone, measures to counter hard and soft tissue loss are frequently necessary. To reduce the morbidity associated with bone and connective tissue procurement, various exogenous materials are utilized. The "Dermal Apron Technique" presented in this article demonstrates the use of a composite bone particulate (allograft/xenograft) plus a dermal allograft, adapted around screw-retained temporary crowns and secured within a subperiosteal pouch. The purpose is to augment the thickness of peri-implant mucosa for the purpose of preserving ridge dimensions and preventing mucosal recession. Controlled studies are required to further support its use. Clinical significance: Soft tissue health and harmony are critical for successful implant therapy in the esthetic regions of the dentition. Often, autogenous soft tissue grafts are used to augment peri-implant soft tissues. The Dermal Apron Technique is a method, that in specific situations, obviates the need for autogenous grafting. This reduces treatment time and morbidity associated with procurement of these grafts. The Dermal Apron Technique is used simultaneous with immediate placement and provisionalization and can improve long-term esthetic outcomes for patients. © 2016 Wiley Periodicals, Inc.

Clad vent set cup closure-weld-zone grinding evaluation

International Nuclear Information System (INIS)

Ulrich, G.B.; Woods, A.T.; Ohriner, E.K.

1996-04-01

Clad vent set (CVS) cups were ground in the closure-weld zone to reduce the wall-thickness variation created by the cup deep-drawing process. A significantly more uniform wall thickness would be beneficial for the CVS closure-weld operation. The goal was to reduce the average within-cup wall-thickness variation (defined as the range of wall thicknesses in the closure-weld zone) approximately 50% from the Cassini production value of 42 microm. This goal was shown to be achievable but, unfortunately, not with the existing blank and formed cup thicknesses

Effect of vadose zone on the steady-state leakage rates from landfill barrier systems

International Nuclear Information System (INIS)

Celik, B.; Rowe, R.K.; Unlue, K.

2009-01-01

Leakage rates are evaluated for a landfill barrier system having a compacted clay liner (CCL) underlain by a vadose zone of variable thickness. A numerical unsaturated flow model SEEP/W is used to simulate the moisture flow regime and steady-state leakage rates for the cases of unsaturated zones with different soil types and thicknesses. The results of the simulations demonstrate that harmonic mean hydraulic conductivity of coarse textured vadose zones is 3-4 orders of magnitude less than saturated hydraulic conductivity; whereas, the difference is only one order of magnitude for fine textured vadose zones. For both coarse and fine textured vadose zones, the effective hydraulic conductivity of the barrier system and the leakage rate to an underlying aquifer increases with increasing thickness of the vadose zone and ultimately reaches an asymptotic value for a coarse textured vadose zone thickness of about 10 m and a fine textured vadose zone thickness of about 5 m. Therefore, the fine and coarse textured vadose zones thicker than about 5 m and 10 m, respectively, act as an effective part of the barrier systems examined. Although the thickness of vadose zone affects the effective hydraulic conductivity of the overall barrier system, the results demonstrated that the hydraulic conductivity of the CCL is the dominant factor controlling the steady-state leakage rates through barrier systems having single low permeability clay layers

Hydrologic conditions controlling runoff generation immediately after wildfire

Science.gov (United States)

Ebel, Brian A.; Moody, John A.; Martin, Deborah A.

2012-01-01

We investigated the control of postwildfire runoff by physical and hydraulic properties of soil, hydrologic states, and an ash layer immediately following wildfire. The field site is within the area burned by the 2010 Fourmile Canyon Fire in Colorado, USA. Physical and hydraulic property characterization included ash thickness, particle size distribution, hydraulic conductivity, and soil water retention curves. Soil water content and matric potential were measured indirectly at several depths below the soil surface to document hydrologic states underneath the ash layer in the unsaturated zone, whereas precipitation and surface runoff were measured directly. Measurements of soil water content showed that almost no water infiltrated below the ash layer into the near-surface soil in the burned site at the storm time scale (i.e., minutes to hours). Runoff generation processes were controlled by and highly sensitive to ash thickness and ash hydraulic properties. The ash layer stored from 97% to 99% of rainfall, which was critical for reducing runoff amounts. The hydrologic response to two rain storms with different rainfall amounts, rainfall intensity, and durations, only ten days apart, indicated that runoff generation was predominantly by the saturation-excess mechanism perched at the ash-soil interface during the first storm and predominantly by the infiltration-excess mechanism at the ash surface during the second storm. Contributing area was not static for the two storms and was 4% (saturation excess) to 68% (infiltration excess) of the catchment area. Our results showed the importance of including hydrologic conditions and hydraulic properties of the ash layer in postwildfire runoff generation models.

Crustal thickness variations in the Zagros continental collision zone (Iran) from joint inversion of receiver functions and surface wave dispersion

Science.gov (United States)

Tatar, M.; Nasrabadi, A.

2013-10-01

Variations in crustal thickness in the Zagros determined by joint inversion of P wave receiver functions (RFs) and Rayleigh wave group and phase velocity dispersion. The time domain iterative deconvolution procedure was employed to compute RFs from teleseismic recordings at seven broadband stations of INSN network. Rayleigh wave phase velocity dispersion curves were estimated employing two-station method. Fundamental mode Rayleigh wave group velocities for each station is taken from a regional scale surface wave tomographic imaging. The main variations in crustal thickness that we observe are between stations located in the Zagros fold and thrust belt with those located in the Sanandaj-Sirjan zone (SSZ) and Urumieh-Dokhtar magmatic assemblage (UDMA). Our results indicate that the average crustal thickness beneath the Zagros Mountain Range varies from ˜46 km in Western and Central Zagros beneath SHGR and GHIR up to ˜50 km beneath BNDS located in easternmost of the Zagros. Toward NE, we observe an increase in Moho depth where it reaches ˜58 km beneath SNGE located in the SSZ. Average crustal thickness also varies beneath the UDMA from ˜50 km in western parts below ASAO to ˜58 in central parts below NASN. The observed variation along the SSZ and UDMA may be associated to ongoing slab steepening or break off in the NW Zagros, comparing under thrusting of the Arabian plate beneath Central Zagros. The results show that in Central Iran, the crustal thickness decrease again to ˜47 km below KRBR. There is not a significant crustal thickness difference along the Zagros fold and thrust belt. We found the same crystalline crust of ˜34 km thick beneath the different parts of the Zagros fold and thrust belt. The similarity of crustal structure suggests that the crust of the Zagros fold and thrust belt was uniform before subsidence and deposition of the sediments. Our results confirm that the shortening of the western and eastern parts of the Zagros basement is small and

Lesion dehydration rate changes with the surface layer thickness during enamel remineralization

Science.gov (United States)

Chang, Nai-Yuan N.; Jew, Jamison M.; Fried, Daniel

2018-02-01

A transparent highly mineralized outer surface zone is formed on caries lesions during remineralization that reduces the permeability to water and plaque generated acids. However, it has not been established how thick the surface zone should be to inhibit the penetration of these fluids. Near-IR (NIR) reflectance coupled with dehydration can be used to measure changes in the fluid permeability of lesions in enamel and dentin. Based on our previous studies, we postulate that there is a strong correlation between the surface layer thickness and the rate of dehydration. In this study, the rates of dehydration for simulated lesions in enamel with varying remineralization durations were measured. Reflectance imaging at NIR wavelengths from 1400-2300 nm, which coincides with higher water absorption and manifests the greatest sensitivity to contrast changes during dehydration measurements, was used to image simulated enamel lesions. The results suggest that the relationship between surface zone thickness and lesion permeability is highly non-linear, and that a small increase in the surface layer thickness may lead to a significant decrease in permeability.

Radially converging tracer test in a low-angle fracture zone at the Finnsjoen site, central Sweden. The fracture zone project - phase 3

International Nuclear Information System (INIS)

Gustafsson, E.; Nordqvist, R.

1993-10-01

The performance and results of a radially converging tracer test in a low-angle major fracture zone in crystalline rock are described. The extensive, about 100 m thick, zone 2 was encountered by means of borehole investigations at depths ranging from 100 to 250 metres at the Finnsjon site, central eastern Sweden. The zone studied (zone 2) consists of highly conductive, metre thick interconnected minor shear and fracture zones (sub-zones) with low conductive rock in between. The objective of the tracer test was primarily to determine flow and transport characteristics in a major fracture zone. Secondly new equipment, experimental design and methods of interpretation were developed, tested and improved. The converging flow field was created by pumping in a central borehole from a packed-off interval enclosing the whole thickness of zone 2. Tracer breakthrough was registered from all nine injection points, with first arrivals ranging from 24 to 3200 hours. Evaluated flow and transport parameters included; flow porosity, dispersivity, flow wetted surface, fracture aperture and hydraulic conductivity in fracture flow paths. Directional variations were found in the flow and transport parameters determined, which is concluded to be due to heterogeneity and/or anisotropy. This conditions is more pronounced at depth in zone 2. The results from the tracer test also clearly show that the upper boundary of zone 2 is highly conductive and consistent over hundreds of metres. Within zone 2, and between upper and lower margins, interconnected discrete minor shear and fracture zones (sub-zones) constitute flow paths of considerable variable residence times. The dispersion within the sub-zones of zone 2, expressed as Peclet numbers ranged from 16 to 40. Flow porosity was determined to be 0.001-0.05 in the upper sub-zone and 0.01-0.1 in the intermediate and lower ones and flow wetted surface area per volume of rock was calculated to be within 1-92 m 2 /m 3 . 68 refs, 61 figs, 40 tabs

Response to recharge variation of thin rainwater lenses and their mixing zone with underlying saline groundwater

Directory of Open Access Journals (Sweden)

S. Eeman

2012-10-01

Full Text Available In coastal zones with saline groundwater, fresh groundwater lenses may form due to infiltration of rain water. The thickness of both the lens and the mixing zone, determines fresh water availability for plant growth. Due to recharge variation, the thickness of the lens and the mixing zone are not constant, which may adversely affect agricultural and natural vegetation if saline water reaches the root zone during the growing season. In this paper, we study the response of thin lenses and their mixing zone to variation of recharge. The recharge is varied using sinusoids with a range of amplitudes and frequencies. We vary lens characteristics by varying the Rayleigh number and Mass flux ratio of saline and fresh water, as these dominantly influence the thickness of thin lenses and their mixing zone. Numerical results show a linear relation between the normalised lens volume and the main lens and recharge characteristics, enabling an empirical approximation of the variation of lens thickness. Increase of the recharge amplitude causes increase and the increase of recharge frequency causes a decrease in the variation of lens thickness. The average lens thickness is not significantly influenced by these variations in recharge, contrary to the mixing zone thickness. The mixing zone thickness is compared to that of a Fickian mixing regime. A simple relation between the travelled distance of the centre of the mixing zone position due to variations in recharge and the mixing zone thickness is shown to be valid for both a sinusoidal recharge variation and actual records of daily recharge data. Starting from a step response function, convolution can be used to determine the effect of variable recharge in time. For a sinusoidal curve, we can determine delay of lens movement compared to the recharge curve as well as the lens amplitude, derived from the convolution integral. Together the proposed equations provide us with a first order approximation of lens

A rapid method to map the crustal and lithospheric thickness using elevation, geoid anomaly and thermal analysis. Application to the Gibraltar Arc System, Atlas Mountains and adjacent zones

Science.gov (United States)

Fullea, J.; Fernàndez, M.; Zeyen, H.; Vergés, J.

2007-02-01

We present a method based on the combination of elevation and geoid anomaly data together with thermal field to map crustal and lithospheric thickness. The main assumptions are local isostasy and a four-layered model composed of crust, lithospheric mantle, sea water and the asthenosphere. We consider a linear density gradient for the crust and a temperature dependent density for the lithospheric mantle. We perform sensitivity tests to evaluate the effect of the variation of the model parameters and the influence of RMS error of elevation and geoid anomaly databases. The application of this method to the Gibraltar Arc System, Atlas Mountains and adjacent zones reveals the presence of a lithospheric thinning zone, SW-NE oriented. This zone affects the High and Middle Atlas and extends from the Canary Islands to the eastern Alboran Basin and is probably linked with a similarly trending zone of thick lithosphere constituting the western Betics, eastern Rif, Rharb Basin, and Gulf of Cadiz. A number of different, even mutually opposite, geodynamic models have been proposed to explain the origin and evolution of the study area. Our results suggest that a plausible slab-retreating model should incorporate tear and asymmetric roll-back of the subducting slab to fit the present-day observed lithosphere geometry. In this context, the lithospheric thinning would be caused by lateral asthenospheric flow. An alternative mechanism responsible for lithospheric thinning is the presence of a hot magmatic reservoir derived from a deep ancient plume centred in the Canary Island, and extending as far as Central Europe.

Implant Therapy in the Esthetic Zone-Surgical Considerations

Directory of Open Access Journals (Sweden)

Marković Aleksa

2016-07-01

Full Text Available Implant placement in the esthetic zone is a complex procedure and requires a restoration-driven approach. Proper selection of patients and implant together with individual assessment of the risk of esthetic complications are very important. Correct 3D-implant positioning and sufficient bone volume should provide long-term esthetic and function. Esthetic region is a zone in which expectations and possibilities collide. Clinician should bring the important decision on the appropriate time of implant placement. Immediate implant placement is particularly challenging in the esthetic zone. Patient desire for reduced treatment time should be weighed against the possible risk factors. Protocol of immediate implant placement in conditions of unfavourable gingival biotypes, the lack of bone or soft tissue in patients with a high smile line lead to esthetic failure which is very important in the esthetic region.

Comparison of ketorolac 0.45% versus diclofenac 0.1% for macular thickness and volume after uncomplicated cataract surgery.

Science.gov (United States)

Lee, Tae Hee; Choi, Won; Ji, Yong Sok; Yoon, Kyung Chul

2016-05-01

To compare the effects of ketorolac 0.45% and diclofenac 0.1% on macular thickness and volume after uncomplicated cataract surgery. A total of 76 eyes of 76 patients who underwent uncomplicated cataract surgery were included. Patients were treated with either diclofenac 0.1% (38 eyes) or ketorolac 0.45% (38 eyes) after surgery. The macular thickness and volume were obtained with optical coherence tomography (OCT). Central subfield thickness (CST, OCT 1 mm zone), total foveal thickness (TFT, OCT 3 mm zone), total macular thickness (TMT, OCT 6 mm zone), average macular thickness (AMT) and total macular volume (TMV) were compared between the two study groups. No significant differences between groups were found in macular thickness or volume 1 month after cataract surgery. Two months after surgery, the ketorolac group had significantly lower CST, TFT, TMT and AMT than the diclofenac group (p diclofenac group. Following uncomplicated cataract surgery, topical ketorolac 0.45% was more effective than diclofenac 0.1% in preventing increases in macular thickness and volume. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

The mobility of growth twins synthesized by sputtering: Tailoring the twin thickness

International Nuclear Information System (INIS)

Velasco, Leonardo; Hodge, Andrea M.

2016-01-01

The current work presents a protean twin thickness contour zone map that illustrates how the nucleation and the mobility of twin boundaries affects the twin thickness of sputtered films. The twin thickness contour zone map can be used as a versatile guide to synthesize fully nanotwinned films with tailored twin thicknesses in materials with a wide range of stacking fault energies. The nucleation and mobility of twin boundaries was studied in four Cu alloys of different compositions (Cu-6wt.%Al, Cu-4wt.%Al, Cu-2wt.%Al, and Cu-10wt.%Ni), having stacking fault energies ranging from 6 mJ/m 2 to 60 mJ/m 2 . The films were synthesized by magnetron sputtering and characterized by transmission electron microscopy, where the twin thickness varied from 2 nm to 35 nm. Our experimental results show that it is possible to control the twin thickness. Three main mechanisms are explained to describe twin nucleation and twin boundary mobility, which are correlated to the interplay of specific sputtering conditions and the deposition temperature.

Effect of connective tissue grafting on peri-implant tissue in single immediate implant sites : A RCT

NARCIS (Netherlands)

Zuiderveld, Elise G; Meijer, Henny J A; den Hartog, Laurens; Vissink, Arjan; Raghoebar, Gerry M

AimTo assess the effect of connective tissue grafting on the mid-buccal mucosal level (MBML) of immediately placed and provisionalized single implants in the maxillofacial aesthetic zone. Materials and methodsSixty patients with a failing tooth were provided with an immediately placed and

On the Explicit Expression for Plasma Layer Thickness

CERN Document Server

Sharma, R K

2004-01-01

The marginal zone theory is used to account for the observed Fahreus Linquist effect when the viscoity of blood changes with the diameter of the capillary. An attributable cause is the axial accumulation of cells. The discharge rate from Hagen Poiseulle law at steady state was derived by Haynes (1960) for the core and plasma layer and a total discharge rate was expressed as a function of the pressure drop along the capillary, quartic dependence on the radius of the capillary and quartic dependence on the dimensionless marginal zone thickness. The apparent of viscosity of the blood is expressed as a function of the ratio of the core layer viscosity and the plasma layer viscosity. In order to back out a marginal zone thickness from a given set of information, the Charm and Kurland expression (1974) for the viscosity and hematocrit variation and the temperature dependence parameter of the hematocrit alpha can be used to develop two transcendental equations and two un! knowns. This is the recommended procedure us...

On a Explicit Expresion for Plasma Layer Thickness

CERN Document Server

Sharma, R K

2004-01-01

The marginal zone theory is used to account for the observed Fahreus Linquist effect when the viscoity of blood changes with the diameter of the capillary. An attributable cause is the axial accumulation of cells. The discharge rate from Hagen Poiseulle law at steady state was derived by Haynes (1960) for the core and plasma layer and a total discharge rate was expressed as a function of the pressure drop along the capillary, quartic dependence on the radius of the capillary and quartic dependence on the dimensionless marginal zone thickness. The apparent of viscosity of the blood is expressed as a function of the ratio of the core layer viscosity and the plasma layer viscosity. In order to back out a marginal zone thickness from a given set of information, the Charm and Kurland expression (1974) for the viscosity and hematocrit variation and the temperature dependence parameter of the hematocrit alpha can be used to develop two transcendental equations and two un! knowns. This is the recommended procedure us...

Effects of Faulted Stratigraphy on Saturated Zone Flow Beneath Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Cohen, Andrew J.B.; Oldenburg, Curtis M.

1999-01-01

The S 4 Z Model (''sub-site-scale saturated zone'') is a 3-D TOUGH2 model that was developed to study the saturated zone (SZ) at Yucca Mountain, Nevada, and to aid in the design and analysis of hydrologic tests. Yucca Mountain is the proposed site for a nuclear waste repository for the United States. The model covers an area of approximately 100 km 2 around Yucca Mountain, as shown in Figure 1. The proposed repository is located in the unsaturated zone, immediately above the area of equidimensional gridblocks east of Solitario Canyon fault, which defines the crest of Yucca Mountain. The finely discretized region near the center of the domain corresponds to the area near a cluster of boreholes used for hydraulic and tracer testing. This discretization facilitates simulation of tests conducted there. The hydrogeologic structure beneath the mountain is comprised of dipping geologic units of variable thickness which are offset by faults. One of the primary objectives of the S 4 Z modeling effort is to study the potential effects of the faulted structure on flow. Therefore, replication of the geologic structure in the model mesh is necessary. This paper summarizes (1) the mesh discretization used to capture the faulted geologic structure, and (2) a model simulation that illustrates the significance of the geologic structure on SZ flow and the resulting macrodispersion

76 FR 63841 - Security Zone; Potomac River, Georgetown Channel, Washington, DC

Science.gov (United States)

2011-10-14

... effect from 6 a.m. until 6 p.m. on October 16, 2011. The security zone will include all navigable waters... security zone at the time it is in effect are to depart the zone immediately. To seek permission to transit... can better evaluate its effects on them and participate in the rulemaking process. Small businesses...

Fabrication techniques of X-ray spiral zone plates

International Nuclear Information System (INIS)

Gao Nan; Zhu Xiaoli; Li Hailiang; Xie Changqing

2010-01-01

The techniques to make X-ray spiral zone plates using electron beam and X-ray lithography were studied. A master mask was fabricated on polyimide membrane by E-beam lithography and micro-electroplating. Spiral zone plates were efficiently replicated by X-ray lithography and micro-electroplating. By combining the techniques, spiral zone plates at 1 keV were successfully fabricate. With an outermost zone width of the 200 nm, and the gold absorbers thickness of 700 nm, the high quality zone plates can be used for X-ray phase contrast microscopy.(authors)

Multichannel imager for littoral zone characterization

Science.gov (United States)

Podobna, Yuliya; Schoonmaker, Jon; Dirbas, Joe; Sofianos, James; Boucher, Cynthia; Gilbert, Gary

2010-04-01

This paper describes an approach to utilize a multi-channel, multi-spectral electro-optic (EO) system for littoral zone characterization. Advanced Coherent Technologies, LLC (ACT) presents their EO sensor systems for the surf zone environmental assessment and potential surf zone target detection. Specifically, an approach is presented to determine a Surf Zone Index (SZI) from the multi-spectral EO sensor system. SZI provides a single quantitative value of the surf zone conditions delivering an immediate understanding of the area and an assessment as to how well an airborne optical system might perform in a mine countermeasures (MCM) operation. Utilizing consecutive frames of SZI images, ACT is able to measure variability over time. A surf zone nomograph, which incorporates targets, sensor, and environmental data, including the SZI to determine the environmental impact on system performance, is reviewed in this work. ACT's electro-optical multi-channel, multi-spectral imaging system and test results are presented and discussed.

Experimental and theoretical study on minimum achievable foil thickness during asymmetric rolling.

Directory of Open Access Journals (Sweden)

Delin Tang

Full Text Available Parts produced by microforming are becoming ever smaller. Similarly, the foils required in micro-machines are becoming ever thinner. The asymmetric rolling technique is capable of producing foils that are thinner than those produced by the conventional rolling technique. The difference between asymmetric rolling and conventional rolling is the 'cross-shear' zone. However, the influence of the cross-shear zone on the minimum achievable foil thickness during asymmetric rolling is still uncertain. In this paper, we report experiments designed to understand this critical influencing factor on the minimum achievable thickness in asymmetric rolling. Results showed that the minimum achievable thickness of rolled foils produced by asymmetric rolling with a rolling speed ratio of 1.3 can be reduced to about 30% of that possible by conventional rolling technique. Furthermore, the minimum achievable thickness during asymmetric rolling could be correlated to the cross-shear ratio, which, in turn, could be related to the rolling speed ratio. From the experimental results, a formula to calculate the minimum achievable thickness was established, considering the parameters cross-shear ratio, friction coefficient, work roll radius, etc. in asymmetric rolling.

Experimental and theoretical study on minimum achievable foil thickness during asymmetric rolling.

Science.gov (United States)

Tang, Delin; Liu, Xianghua; Song, Meng; Yu, Hailiang

2014-01-01

Parts produced by microforming are becoming ever smaller. Similarly, the foils required in micro-machines are becoming ever thinner. The asymmetric rolling technique is capable of producing foils that are thinner than those produced by the conventional rolling technique. The difference between asymmetric rolling and conventional rolling is the 'cross-shear' zone. However, the influence of the cross-shear zone on the minimum achievable foil thickness during asymmetric rolling is still uncertain. In this paper, we report experiments designed to understand this critical influencing factor on the minimum achievable thickness in asymmetric rolling. Results showed that the minimum achievable thickness of rolled foils produced by asymmetric rolling with a rolling speed ratio of 1.3 can be reduced to about 30% of that possible by conventional rolling technique. Furthermore, the minimum achievable thickness during asymmetric rolling could be correlated to the cross-shear ratio, which, in turn, could be related to the rolling speed ratio. From the experimental results, a formula to calculate the minimum achievable thickness was established, considering the parameters cross-shear ratio, friction coefficient, work roll radius, etc. in asymmetric rolling.

Debris thickness patterns on debris-covered glaciers

Science.gov (United States)

Anderson, Leif S.; Anderson, Robert S.

2018-06-01

Many debris-covered glaciers have broadly similar debris thickness patterns: surface debris thickens and tends to transition from convex- to concave-up-down glacier. We explain this pattern using theory (analytical and numerical models) paired with empirical observations. Down glacier debris thickening results from the conveyor-belt-like nature of the glacier surface in the ablation zone (debris can typically only be added but not removed) and from the inevitable decline in ice surface velocity toward the terminus. Down-glacier thickening of debris leads to the reduction of sub-debris melt and debris emergence toward the terminus. Convex-up debris thickness patterns occur near the up-glacier end of debris covers where debris emergence dominates (ablation controlled). Concave-up debris thickness patterns occur toward glacier termini where declining surface velocities dominate (velocity controlled). A convex-concave debris thickness profile inevitably results from the transition between ablation-control and velocity-control down-glacier. Debris thickness patterns deviating from this longitudinal shape are most likely caused by changes in hillslope debris supply through time. By establishing this expected debris thickness pattern, the effects of climate change on debris cover can be better identified.

Assessment of TS-1, a thick cane mutant

International Nuclear Information System (INIS)

Shama Rao, H.K.

1979-01-01

A true breeding thick cane mutant TS-1, induced by radiations, was obtained in variety Co-419. TS-1 was found to be superior to Co-419 with respect to cane size, weight, yield and juice quality. The thick canes of TS-1 were found to be solid even at 14 months age and so also their ratoons. The tillering habit of TS-1 has a definite advantage over other varieties with respect to easy intercultural field operations. TS-1 is now being tested under various agroclimatic zones in Karnataka, Maharashtra and U.P. (auth.)

Creating Esthetic Harmony with Nonloading, Fixed Provisional Restoration using Extracted Teeth after Immediate Implant Placement.

Science.gov (United States)

Satwalekar, Parth; Satwalekar, Tanushree; Bondugula, Vasanthi; Bhuvaneshwari, B; Harshavardhan, K V; Pasula, Kiran

2016-04-01

To make use of fiber-reinforced composite and the patient's own extracted teeth in fabricating a provisional restoration following immediate implant placement. Fiber-reinforced composites offer various possibilities in temporization of osseointegrating implants in the esthetic zone. In this chairside technique, the patient's own extracted teeth with fiber-reinforced composite were used to fabricate a provisional restoration after immediate implant placement. A putty index was made before extracting the teeth and placing the implants as planned. The index and crowns of the extracted teeth were used to make a nonloading, esthetic, chair-side provisional restoration after immediate implant placement. By using the patient's own teeth for pro-visionalization immediately after implant placement, acceptance is greatly enhanced.

Immediate placement and restoration of dental implants in the esthetic region: clinical case series.

Science.gov (United States)

Khzam, Nabil; Mattheos, Nikos; Roberts, David; Bruce, William L; Ivanovski, Saso

2014-01-01

The objective of this study was to assess the hard and soft tissue changes following immediate placement and provisional restoration of single-tooth implants in the aesthetic zone. Thirteen patients with immediately placed and restored implants were included in this study. All participating patients underwent the same treatment strategy that involved removal of the failed tooth, flapless surgery, immediate implant placement, and connection of a screw-retained provisional restoration. Three months following implant placement, the temporary crowns were replaced by the definitive restorations. Implant survival rates, and hard and soft tissue changes were measured using periapical X-rays and photographs. The range of the observation period was between 12 and 37 months with a mean period of 23.2 ± 7.6 months. At the time of follow-up, all implants were present with no complications. Radiographic evaluation revealed a mean mesial bone gain of 1.20 ± 1.01 mm and a mean distal bone gain of 0.80 ± 1.14 mm, which reached statistical significance. The mean mid-buccal recession was 0.20 ± 0.78 mm, whereas the mesial and distal papillae height loss was 0.50 ± 1.26 mm and 0.30 ± 0.82 mm, respectively. The changes in the soft tissues did not reach statistical significance. Notwithstanding the limitation of a small sample size, this study shows that immediate implant placement and provisional restoration in the maxillary aesthetic zone can result in favorable treatment outcomes with regards to soft and hard tissues changes over a follow-up period of 23.2 ± 7.6 months. Most clinical trials investigating immediate implant placement and immediate restoration in the maxillary anterior zone have focused on implant survival and implant success, with particular emphasis on radiographically assessed hard tissues changes. However, this study assesses the soft tissue changes associated with this procedure, which is an important area of study

Mechanism of Rock Burst Occurrence in Specially Thick Coal Seam with Rock Parting

Science.gov (United States)

Wang, Jian-chao; Jiang, Fu-xing; Meng, Xiang-jun; Wang, Xu-you; Zhu, Si-tao; Feng, Yu

2016-05-01

Specially thick coal seam with complex construction, such as rock parting and alternative soft and hard coal, is called specially thick coal seam with rock parting (STCSRP), which easily leads to rock burst during mining. Based on the stress distribution of rock parting zone, this study investigated the mechanism, engineering discriminant conditions, prevention methods, and risk evaluation method of rock burst occurrence in STCSRP through setting up a mechanical model. The main conclusions of this study are as follows. (1) When the mining face moves closer to the rock parting zone, the original non-uniform stress of the rock parting zone and the advancing stress of the mining face are combined to intensify gradually the shearing action of coal near the mining face. When the shearing action reaches a certain degree, rock burst easily occurs near the mining face. (2) Rock burst occurrence in STCSRP is positively associated with mining depth, advancing stress concentration factor of the mining face, thickness of rock parting, bursting liability of coal, thickness ratio of rock parting to coal seam, and difference of elastic modulus between rock parting and coal, whereas negatively associated with shear strength. (3) Technologies of large-diameter drilling, coal seam water injection, and deep hole blasting can reduce advancing stress concentration factor, thickness of rock parting, and difference of elastic modulus between rock parting and coal to lower the risk of rock burst in STCSRP. (4) The research result was applied to evaluate and control the risk of rock burst occurrence in STCSRP.

The Effect of Selected Conditions in a Thermoforming Process on Wall Thickness Variations

Directory of Open Access Journals (Sweden)

Emil Sasimowski

2017-12-01

Full Text Available The paper reports the results of a study on the effect of selected conditions in a thermoforming process for thin polystyrene sheet by vacuum assisted drape forming on the wall thickness non-uniformity of finished parts. The investigation was performed using Statistica’s DOE module for three variables: temperatures in the external and internal zones of the heater as well as heating time of the plastic sheet. The results demonstrate that the wall thickness in the finished parts at the measuring points is primarily affected by the heating time and the temperature in the internal zone of the heater, while the temperature in the external zone only affects some regions of the finished part. The results demonstrate that a short heating time and hence a lower temperature of the plastic sheet lead to a more uniform deformation of both the bottom and the side walls of the finished part, and as a consequence, to smaller variations in the wall thickness. The shortening of the heating time is however limited by the necessity of accurate reproduction of the shape of the finished part.

Mechanical properties of fracture zones

International Nuclear Information System (INIS)

Leijon, B.

1993-05-01

Available data on mechanical characteristics of fracture zones are compiled and discussed. The aim is to improve the basis for adequate representation of fracture zones in geomechanical models. The sources of data researched are primarily borehole investigations and case studies in rock engineering, involving observations of fracture zones subjected to artificial load change. Boreholes only yield local information about the components of fracture zones, i.e. intact rock, fractures and various low-strength materials. Difficulties are therefore encountered in evaluating morphological and mechanical properties of fracture zones from borehole data. Although often thought of as macroscopically planar features, available field data consistently show that fracture zones are characterized by geometrical irregularities such as thickness variations, surface undulation and jogs. These irregularities prevail on all scales. As a result, fracture zones are on all scales characterized by large, in-plane variation of strength- and deformational properties. This has important mechanical consequences in terms of non-uniform stress transfer and complex mechanisms of shear deformation. Field evidence for these findings, in particular results from the underground research laboratory in Canada and from studies of induced fault slip in deep mines, is summarized and discussed. 79 refs

Approximate solutions for radial travel time and capture zone in unconfined aquifers.

Science.gov (United States)

Zhou, Yangxiao; Haitjema, Henk

2012-01-01

Radial time-of-travel (TOT) capture zones have been evaluated for unconfined aquifers with and without recharge. The solutions of travel time for unconfined aquifers are rather complex and have been replaced with much simpler approximate solutions without significant loss of accuracy in most practical cases. The current "volumetric method" for calculating the radius of a TOT capture zone assumes no recharge and a constant aquifer thickness. It was found that for unconfined aquifers without recharge, the volumetric method leads to a smaller and less protective wellhead protection zone when ignoring drawdowns. However, if the saturated thickness near the well is used in the volumetric method a larger more protective TOT capture zone is obtained. The same is true when the volumetric method is used in the presence of recharge. However, for that case it leads to unreasonableness over the prediction of a TOT capture zone of 5 years or more. © 2011, The Author(s). Ground Water © 2011, National Ground Water Association.

Innovative Extraction Method for a Coal Seam with a Thick Rock-Parting for Supporting Coal Mine Sustainability

Directory of Open Access Journals (Sweden)

Meng Li

2017-10-01

Full Text Available As thick rock partings delay the efficient mining of coal seams and constrain the sustainable development of coal mines, an innovative extraction method for a coal seam with thick rock parting was proposed. The coal seams were divided into different sub-zones according to the thickness of rock parting and then the sub-zones were mined by separately using three mining schemes involving full-seam mining, combined mining using backfill and caving (CMBC, and reducing height mining. Afterwards, the study introduced the basic mechanism and key devices for the CMBC and analysed the working state of the backfill support in detail. Moreover, the method for calculating the length of the backfill zone was proposed to design the length of backfill zone and the influences of four factors (including bulking coefficient of rock parting on the length of the backfill zone were also explored. By taking the No. 22203 panel, Buertai mine, Inner Mongolia, China as an example, the mined coal resource by using the CMBC extraction method will increase by 1.83 × 106 tons and the recovery ratio will rise from 56.2% to 92.4% compared with mining of the 2-2 upper coal seam alone. Moreover, by applying CMBC, a series of environmental and ecological problems caused by rock parting is reduced, which can improve the environment in mined areas. The research can provide technological guidance for mining panels of a coal seam with a thick rock parting and the disposal thereof under similar conditions.

Eruption and emplacement dynamics of a thick trachytic lava flow of the Sancy volcano (France)

Science.gov (United States)

Latutrie, Benjamin; Harris, Andrew; Médard, Etienne; Gurioli, Lucia

2017-01-01

A 70-m-thick, 2200-m-long (51 × 106 m3) trachytic lava flow unit underlies the Puy de Cliergue (Mt. Dore, France). Excellent exposure along a 400-m-long and 60- to 85-m-high section allows the flow interior to be accessed on two sides of a glacial valley that cuts through the unit. We completed an integrated morphological, structural, textural, and chemical analysis of the unit to gain insights into eruption and flow processes during emplacement of this thick silicic lava flow, so as to elucidate the chamber and flow dynamic processed that operate during the emplacement of such systems. The unit is characterized by an inverse chemical stratification, where there is primitive lava beneath the evolved lava. The interior is plug dominated with a thin basal shear zone overlying a thick basal breccia, with ramping affecting the entire flow thickness. To understand these characteristics, we propose an eruption model that first involves processes operating in the magma chamber whereby a primitive melt is injected into an evolved magma to create a mixed zone at the chamber base. The eruption triggered by this event first emplaced a trachytic dome, into which banded lava from the chamber base was injected. Subsequent endogenous dome growth led to flow down the shallow slope to the east on which the highly viscous (1012 Pa s) coulée was emplaced. The flow likely moved extremely slowly, being emplaced over a period of 4-10 years in a glacial manner, where a thick (>60-m) plug slid over a thin (5-m-thick) basal shear zone. Excellent exposure means that the Puy de Cliergue complex can be viewed as a case type location for understanding and defining the eruption and emplacement of thick, high-viscosity, silicic lava flow systems.

Immediate Reconstruction of Failed Implants in the Esthetic Zone Using a Flapless Technique and Autogenous Composite Tuberosity Graft

NARCIS (Netherlands)

Raghoebar, Gerry M; Meijer, Henny J A; van Minnen, Baucke; Vissink, Arjan

We describe a technique for immediate reconstruction of bone after removal of failed dental implants in the esthetic region to optimize the esthetic outcome of retreatment. We conducted a study of 16 consecutive patients in whom the bony defect resulting from implant removal was immediately

New insight on the paleoproterozoic evolution of the São Francisco Craton: Reinterpretation of the geology, the suture zones and the thicknesses of the crustal blocks using geophysical and geological data

Science.gov (United States)

Sampaio, Edson E. S.; Barbosa, Johildo S. F.; Correa-Gomes, Luiz C.

2017-07-01

The Archean-Paleoproterozoic Jequié (JB) and Itabuna-Salvador-Curaçá (ISCB) blocks and their tectonic transition zone in the Valença region, Bahia, Brazil are potentially important for ore deposits, but the geological knowledge of the area is still meager. The paucity of geological information restricts the knowledge of the position and of the field characteristics of the tectonic suture zone between these two crustal segments JB and ISCB. Therefore, interpretation of geophysical data is necessary to supplement the regional structural and petrological knowledge of the area as well as to assist mining exploration programs. The analysis of the airborne radiometric and magnetic data of the region has established, respectively, five radiometric domains and five magnetic zones. Modeling of a gravity profile has defined the major density contrasts of the deep structures. The integrated interpretation of the geophysical data fitted to the known geological information substantially improved the suture zone (lower plate JB versus upper plate ISCB) delimitation, the geological map of the area and allowed to estimate the thicknesses of these two blocks, and raised key questions about the São Francisco Craton tectonic evolution.

Multilayer on-chip stacked Fresnel zone plates: Hard x-ray fabrication and soft x-ray simulations

Energy Technology Data Exchange (ETDEWEB)

Li, Kenan; Wojcik, Michael J.; Ocola, Leonidas E.; Divan, Ralu; Jacobsen, Chris

2015-11-01

Fresnel zone plates are widely used as x-ray nanofocusing optics. To achieve high spatial resolution combined with good focusing efficiency, high aspect ratio nanolithography is required, and one way to achieve that is through multiple e-beam lithography writing steps to achieve on-chip stacking. A two-step writing process producing 50 nm finest zone width at a zone thickness of 1.14 µm for possible hard x-ray applications is shown here. The authors also consider in simulations the case of soft x-ray focusing where the zone thickness might exceed the depth of focus. In this case, the authors compare on-chip stacking with, and without, adjustment of zone positions and show that the offset zones lead to improved focusing efficiency. The simulations were carried out using a multislice propagation method employing Hankel transforms.

The Sorong Fault Zone, Indonesia: Mapping a Fault Zone Offshore

Science.gov (United States)

Melia, S.; Hall, R.

2017-12-01

The Sorong Fault Zone is a left-lateral strike-slip fault zone in eastern Indonesia, extending westwards from the Bird's Head peninsula of West Papua towards Sulawesi. It is the result of interactions between the Pacific, Caroline, Philippine Sea, and Australian Plates and much of it is offshore. Previous research on the fault zone has been limited by the low resolution of available data offshore, leading to debates over the extent, location, and timing of movements, and the tectonic evolution of eastern Indonesia. Different studies have shown it north of the Sula Islands, truncated south of Halmahera, continuing to Sulawesi, or splaying into a horsetail fan of smaller faults. Recently acquired high resolution multibeam bathymetry of the seafloor (with a resolution of 15-25 meters), and 2D seismic lines, provide the opportunity to trace the fault offshore. The position of different strands can be identified. On land, SRTM topography shows that in the northern Bird's Head the fault zone is characterised by closely spaced E-W trending faults. NW of the Bird's Head offshore there is a fold and thrust belt which terminates some strands. To the west of the Bird's Head offshore the fault zone diverges into multiple strands trending ENE-WSW. Regions of Riedel shearing are evident west of the Bird's Head, indicating sinistral strike-slip motion. Further west, the ENE-WSW trending faults turn to an E-W trend and there are at least three fault zones situated immediately south of Halmahera, north of the Sula Islands, and between the islands of Sanana and Mangole where the fault system terminates in horsetail strands. South of the Sula islands some former normal faults at the continent-ocean boundary with the North Banda Sea are being reactivated as strike-slip faults. The fault zone does not currently reach Sulawesi. The new fault map differs from previous interpretations concerning the location, age and significance of different parts of the Sorong Fault Zone. Kinematic

Loess Thickness Variations Across the Loess Plateau of China

Science.gov (United States)

Zhu, Yuanjun; Jia, Xiaoxu; Shao, Mingan

2018-01-01

The soil thickness is very important for investigating and modeling soil-water processes, especially on the Loess Plateau of China with its deep loess deposit and limited water resources. A digital elevation map (DEM) of the Loess Plateau and neighborhood analysis in ArcGIS software were used to generate a map of loess thickness, which was then validated by 162 observations across the plateau. The generated loess thickness map has a high resolution of 100 m × 100 m. The map indicates that loess is thick in the central part of the plateau and becomes gradually shallower in the southeast and northwest directions. The areas near mountains and river basins have the shallowest loess deposit. The mean loess thickness is the deepest in the zones with 400-600-mm precipitation and decreases gradually as precipitation varies beyond this range. Our validation indicates that the map just slightly overestimates loess thickness and is reliable. The loess thickness is mostly between 0 and 350 m in the Loess Plateau region. The calculated mean loess thickness is 105.7 m, with the calibrated value being 92.2 m over the plateau exclusive of the mountain areas. Our findings provide very basic data of loess thickness and demonstrate great progress in mapping the loess thickness distribution for the plateau, which are valuable for a better study of soil-water processes and for more accurate estimations of soil water, carbon, and solute reservoirs in the Loess Plateau of China.

Pengaruh Variasi Lip Thickness pada Nozzle Terpancung terhadap Karakteristik Api Pembakaran Difusi Concentric Jet Flow

Directory of Open Access Journals (Sweden)

Elka Faizal

2016-05-01

Full Text Available Nozzle shape greatly influence turbulence between the fuel, air and formation of flow recirculation zone to produce a homogeneous mixing and get a near-perfect combustion. The recirculation zone is area that caused by flow rate breakdown, causing vortex and backflow around the end of nozzle. This backflow that hold up while lowering the flame so the flow rate of fuel and air mixture maintained lower or equal with flame speed. This study used variation of lip thickness of truncated nozzle 0, 4, 8, 12, and 16 mm.To obtain flame stability, fuel velocity and air velocity were variated. Thermocouples were used to measure flame temperature and its distribution. The results showed that stability of concentric jet diffusion flame flow increased with narrow lip thickness on a truncated nozzle. The wider stability area obtained in 4 mm lip thickness. In addition, temperature on diffusion flames concentric jet flow also more evenly distributed evenly with size of the nozzle lip thickness. The highest temperature and temperature distribution in the horizontal direction were occured in in the nozzle with lip thickness of 0 mm. A shadowgrapgh visualization was also used to identify phenomena of the nozzle exit flow.

Immediate implant placement and provisionalization with simultaneous guided bone regeneration in the esthetic zone

Directory of Open Access Journals (Sweden)

Chih-Long Chen

2011-03-01

Full Text Available The procedure for immediate implant placement and provisionalization is time-saving, possibly with only one surgical intervention required, although allowing maximal preservation of peri-implant tissues. In this case, we extracted a fractured maxillary right central incisor of a 46-year-old woman with high esthetic expectations, and a transmucosal implant was immediately installed. Simultaneous guided bone regeneration was performed to correct the defects at the facial side of the socket and augment the alveolar ridge horizontally. Primary stability of the implant body and wound closure without tension were confirmed. Connection of a 15° angled abutment and fabrication of a provisional acrylic resin crown without occlusal contact were also completed in the same appointment. After intensive follow-up and soft-tissue molding for 6 months, the customized zirconia abutment and all-ceramic crown were definitively fabricated. During the 18-month follow-up period, the patient was satisfied with the esthetic and functional results.

Adjacent-cell Preconditioners for solving optically thick neutron transport problems

International Nuclear Information System (INIS)

Azmy, Y.Y.

1994-01-01

We develop, analyze, and test a new acceleration scheme for neutron transport methods, the Adjacent-cell Preconditioner (AP) that is particularly suited for solving optically thick problems. Our method goes beyond Diffusion Synthetic Acceleration (DSA) methods in that it's spectral radius vanishes with increasing cell thickness. In particular, for the ID case the AP method converges immediately, i.e. in one iteration, to 10 -4 pointwise relative criterion in problems with dominant cell size of 10 mfp or thicker. Also the AP has a simple formalism and is cell-centered hence, multidimensional and high order extensions are easier to develop, and more efficient to implement

Application of InSAR and Gravimetry for Land Subsidence Hazard Zoning in Aguascalientes, Mexico

Directory of Open Access Journals (Sweden)

Jesús Pacheco-Martínez

2015-12-01

Full Text Available In this work we present an application of InSAR and gravimetric surveys for risk management related to land subsidence and surface ground faulting generation. A subsidence velocity map derived from the 2007–2011 ALOS SAR imagery and a sediment thicknesses map obtained from the inversion of gravimetric data were integrated with a surface fault map to produce a subsidence hazard zoning in the city of Aguascalientes, Mexico. The resulting zoning is presented together with specific recommendations about geotechnical studies needed for further evaluation of surface faulting in these hazard zones. The derived zoning map consists in four zones including null hazard (stable terrain without subsidence, low hazard (areas prone to subsidence, medium hazard (zones with subsidence and high hazard (zones with surface faulting. InSAR results displayed subsidence LOS velocities up to 10 cm/year and two subsidence areas unknown before this study. Gravimetric results revealed that the thicker sediment sequence is located toward north of Aguascalientes City reaching up to 600 m in thickness, which correspond to a high subsidence LOS velocity zone (up to 6 cm/year.

Anti-scar Treatment for Deep Partial-thickness Burn Wounds

Science.gov (United States)

2017-10-01

applied topically to deep partial-thickness burn wounds reduced α-SMA protein expression ( ELISA ). Mouse burn wounds were treated with PFD twice...immediately and at 48 hrs post- burn. α-SMA in wound skin homogenates was assayed by ELISA . α-SMA protein was significantly lower in mice treated with...Inflammatory cytokines in wound skin homogenates were assayed by ELISA . This early treatment during the inflammatory stage of healing significantly reduced

Special zone territory decontamination

International Nuclear Information System (INIS)

Samojlenko, Yu.N.; Golubev, V.V.

1989-01-01

Special zone is the Chernobyl' NPP operating site (OS). OS decontamination is described including reactor ruins from the accident moment. The process was begun from reactor bombardment with absorbing and filtering materials (sand, clay, lead, boron compounds). Then were produced soil shovelling, territory filling by dry concrete and laying concrete layer with thickness up to 300 mm. NPP room and equipment decontamination is described. 3 figs.; 3 tabs

Progress in the fabrication of high aspect ratio zone plates by soft x-ray lithography

International Nuclear Information System (INIS)

Divan, R.; Mancini, D. C.; Moldovan, N. A.; Lai, B.; Assoufid, L.; Leondard, Q.; Cerrina, F.

2002-01-01

Fabrication of Fresnel zone plates for the hard x-ray spectral region combines the challenge of high lateral resolution (∼100 nm) with a large thickness requirement for the phase-shifting material (0.5-3 (micro)m). For achieving a high resolution, the initial mask was fabricated by e-beam lithography and gold electroforming. To prevent the collapse of the structures between the developing and electroforming processes, drying was completely eliminated. Fabrication errors, such as nonuniform gold electroplating and collapse of structures, were systematically analyzed and largely eliminated. We optimized the exposure and developing processes for 950k and 2200k polymethylmethacrylate of different thicknesses and various adhesion promoters. We discuss the effects of these fabrication steps on the zone plate's resolution and aspect ratio. Fresnel zone plates with 110 nm outermost zone width, 150 (micro)m diameter, and 1.3 (micro)m gold thickness were fabricated. Preliminary evaluation of the FZPs was done by scanning electron microscopy and atomic force microscopy. The FZP focusing performance was characterized at the Advanced Photon Source at Argonne National Laboratory

Influence of custom-made implant designs on the biomechanical performance for the case of immediate post-extraction placement in the maxillary esthetic zone: a finite element analysis.

Science.gov (United States)

Chen, Jianyu; Zhang, Zhiguang; Chen, Xianshuai; Zhang, Xiao

2017-05-01

Due to the increasing adoption of immediate implantation strategies and the rapid development of the computer aided design/computer aided manufacturing technology, a therapeutic concept based on patient-specific implant dentistry has recently been reintroduced by many researchers. However, little information is available on the designs of custom-made dental implant systems, especially their biomechanical behavior. The influence of the custom-made implant designs on the biomechanical performance for both an immediate and a delayed loading protocol in the maxillary esthetic zone was evaluated by means of the finite element (FE) method. FE models of three dental implants were considered: a state of the art cylindrical implant and two custom-made implants designed by reverse engineering technology, namely a root-analogue implant and a root-analogue threaded implant. The von Mises stress distributions and micro-motions around the bone-implant interfaces were calculated using ANSYS software. In a comparison of the three implant designs for both loading protocols, a favorable biomechanical performance was observed for the use of root-analogue threaded implant which approximated the geometry of natural anterior tooth and maintained the original long-axis. The results indicated that bone-implant interfacial micro-motion was reduced and a favorable stress distribution after osseointegration was achieved.

Managed aquifer recharge of treated wastewater: water quality changes resulting from infiltration through the vadose zone.

Science.gov (United States)

Bekele, Elise; Toze, Simon; Patterson, Bradley; Higginson, Simon

2011-11-01

Secondary treated wastewater was infiltrated through a 9 m-thick calcareous vadose zone during a 39 month managed aquifer recharge (MAR) field trial to determine potential improvements in the recycled water quality. The water quality improvements of the recycled water were based on changes in the chemistry and microbiology of (i) the recycled water prior to infiltration relative to (ii) groundwater immediately down-gradient from the infiltration gallery. Changes in the average concentrations of several constituents in the recycled water were identified with reductions of 30% for phosphorous, 66% for fluoride, 62% for iron and 51% for total organic carbon when the secondary treated wastewater was infiltrated at an applied rate of 17.5 L per minute with a residence time of approximately four days in the vadose zone and less than two days in the aquifer. Reductions were also noted for oxazepam and temazepam among the pharmaceuticals tested and for a range of microbial pathogens, but reductions were harder to quantify as their magnitudes varied over time. Total nitrogen and carbamazepine persisted in groundwater down-gradient from the infiltration galleries. Infiltration does potentially offer a range of water quality improvements over direct injection to the water table without passage through the unsaturated zone; however, additional treatment options for the non-potable water may still need to be considered, depending on the receiving environment or the end use of the recovered water. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

The giant protein titin regulates the length of the striated muscle thick filament.

Science.gov (United States)

Tonino, Paola; Kiss, Balazs; Strom, Josh; Methawasin, Mei; Smith, John E; Kolb, Justin; Labeit, Siegfried; Granzier, Henk

2017-10-19

The contractile machinery of heart and skeletal muscles has as an essential component the thick filament, comprised of the molecular motor myosin. The thick filament is of a precisely controlled length, defining thereby the force level that muscles generate and how this force varies with muscle length. It has been speculated that the mechanism by which thick filament length is controlled involves the giant protein titin, but no conclusive support for this hypothesis exists. Here we show that in a mouse model in which we deleted two of titin's C-zone super-repeats, thick filament length is reduced in cardiac and skeletal muscles. In addition, functional studies reveal reduced force generation and a dilated cardiomyopathy (DCM) phenotype. Thus, regulation of thick filament length depends on titin and is critical for maintaining muscle health.

Impact of human wildlife conflict on socio-economy of support zone ...

African Journals Online (AJOL)

Impact of human wildlife conflict on socio-economy of support zone ... who mostly dependent on natural resources of their immediate environment. ... Most of the victims attack and kill the animals as a management method in both communities.

Prediction of permeability changes in an excavation response zone

International Nuclear Information System (INIS)

Kinoshita, Naoto; Ishii, Takashi; Kuroda, Hidetaka; Tada, Hiroyuki

1992-01-01

In geologic disposal of radioactive wastes, stress changes due to cavern excavation may expand the existing fractures and create possible bypasses for groundwater. This paper proposes a simple method for predicting permeability changes in the excavation response zones. Numerical analyses using this method predict that the response zones created by cavern excavation would differ greatly in thickness and permeability depending on the depth of the cavern site and the initial in-situ stress, that when the cavern site is deeper, response zones would expand more and permeability would increases more, and that if the ratio of horizontal to vertical in-situ stress is small, extensive permeable zones at the crown and the bottom would occur, whereas if the ratio is large, extensive permeable zones would occur in the side walls. (orig.)

Definition of a critical confining zone using surface geophysical methods

International Nuclear Information System (INIS)

Eddy-Dilek, C.A.; Hoekstra, P.; Harthill, N.; Blohm, M.; Phillips, D.R.

1996-01-01

Definition of the hydrogeologic framework in layered sediments of fluvial and deltaic origin is a difficult challenge for environmental characterization and remediation programs due to the lithologic and stratigraphic heterogeneities inherent in these settings. These heterogeneties often control contaminant transport and the effectiveness of remediation alternatives, Surface geophysical surveys can be cost-effective methods for characterization, but individual methods have inherent limitations in resolution and sensitivity. A synergistic approach, utilizing two geophysical survey methods was applied, to define and examine the nature and extent of a deep confining zone of regulatory importance, the Crouch Branch Confining Unit, in Coastal Plain sediments at the Savannah River Site. TDEM accurately maps the overall conductance (product of thickness and electrical conductivity) of a confining zone clay facies; from variation in conductance, changes in lithology of the conforming zone can be inferred. Shear wave seismic reflection surveys map the depth to the clay layers, and the clay layer thickness, but provides little information on the lithologic nature of the confining zone. Integrated interpretation of the combined data set (including all available borehole logs) allows for delineation of the lateral and vertical extent of clay-dominated zones, sand-dominated zones, key stratigraphic horizons, and erosional features associated with unconformities. This approach has resulted in the collection of critical information that will be used to optimize remedial system design, representing a significant cost savings to environmental restoration programs at the Savannah River Site

Development of measurement technique for crack depth in weld zone of thick stainless steel pipe with ultrasonic phased array TOFD

International Nuclear Information System (INIS)

Ishida, Hitoshi

2006-01-01

Phased array TOFD (time of flight diffraction) method which makes possible to detect tip diffraction echoes and measure crack depth in an austenitic stainless steel weld zone with a thickness of more than 25 mm to which region it was difficult to apply ultrasonic test due to scattering of ultrasonic waves has been developed. The developed method uses a single array transducer to have a short distance between incident points of transmitter and receiver in order to propagate waves in shorter pass in the weld region. Transmitting and receiving ultrasonic beams from a single array probe can be set a crossing point and a focal point at desired depth. This method makes possible to scan with 16 kinds of combination of crossing points and focal pints of ultrasonic beam at a time. We have examined fundamental characteristics of depth measurement with electric discharge machining slits on base metal of a stainless steel with a thickness of 35 mm. As the results: (1) We could measure the slit depth with 0.2mm error from the slit depth with a estimating method of a lateral wave propagation time with back wall echo. (2) The largest error of the depth measurement from the slit depth with the ultrasonic beam crossing point set at the 4mm different point from the tip of the slit was 0.3 mm. (3) The largest error of the depth measurements due to the difference of focal point depth of ultrasonic beam was 0.2 mm. (4) The highest tip diffraction echo could be observed with the ultrasonic beam cross point set at the tip of the slit. The difference of 4 mm between the cross point and the tip of the slit caused attenuation of tip diffraction echo height in -6.8 dB. Furthermore we have measured a depth of electric discharge machining slits, fatigue cracks and stress corrosion cracking (SCC) on stainless steel welded pipe specimens with a thickness of 35 mm. As the results: (1) We could detect the tip diffraction echoes which have a signal noise ratio with more than 2.4 from the fatigue

Development of background reduced Fresnel phase zone plate

International Nuclear Information System (INIS)

Tamari, Yohei; Azechi, Hiroshi

2004-01-01

In study of hot and dense plasma, a high spatial resolution (a few microns) x-ray imaging is very important to observe these plasmas. The Fresnel phase zone plate (FPZP) consists of alternately material and transparent circular annuli placed concentrically, which image x rays using diffraction x rays from all annuli. FPZP have imaged 4.7-4.77 keV x rays with 2.2 μm spatial resolution. However FPZP has a problem that background level is comparable to signal level. In subtraction of background, the error of 10% is caused. For the accurate background subtraction, we designed new FPZP, which consist of three β layers of a transparent zone and two material zones. The new design FPZP parameters (thickness of material zones, each zone width) have been optimized, and in that optimum design signal-to-background ratio is 4 times better than conventional two layers FPZP

Cyclic changes of the junctional zone on 3 T MRI images in young and middle-aged females during the menstrual cycle

International Nuclear Information System (INIS)

He, Y.L.; Ding, N.; Li, Y.; Li, Z.; Xiang, Y.; Jin, Z.Y.; Xue, H.D.

2016-01-01

Aim: To evaluate the cyclic changes of the junctional zone in different age groups during the menstrual cycle using 3 T magnetic resonance imaging (MRI), and to investigate the correlation with basic female hormone levels. Materials and methods: Thirty-eight normal volunteers (age range, 20–40 years; mean age, 29 years: 20–30 years, n=22; 31–40 years, n=16) with regular menstrual cycles underwent a pelvic 3 T MRI examination on the 2nd or 3rd days of their menstrual phase (MP), follicular phase (FP), peri-ovulatory phase (OP), and luteal phase (LP), respectively, including a T2-weighted three-dimensional (3D) turbo spin-echo (TSE) with variable flip angle (“SPACE”) sequence, a T2-weighted mapping sequence, and diffusion tensor imaging (DTI). The thickness, T2, fractional anisotropy (FA), and apparent diffusion coefficient (ADC) values of the junctional zone on mid-sagittal images were separately measured by two radiologists on the post-processed workstation. The linear mixed model and one-way analysis of variance were used to evaluate the differences between the two age groups during the four phases. The serum levels of oestradiol (E), progesterone (P), luteinising hormone (LH), and follicle-stimulating hormone (FSH) were measured during the MP and compared with anatomical and functional MRI values using Pearson's correlation analysis. Results: The thickness of the anterior and posterior junctional zone increased with age (p<0.05). In the 20–30 year age group, during the MP the junctional zone was significantly thicker than at the other three phases (p<0.05). Serum E levels correlated moderately with variation in thickness during the menstrual cycle. In the 30–40 year age group, no statistical difference in the thickness was found during the menstrual cycle. As age increased, the ADC values of the junctional zone decreased (p=0.02). In both groups, the ADC and T2 values of the junctional zone showed significant differences between the MP and LP (p<0

Immediate placement of dental implants in the esthetic zone : a systematic review and pooled analysis

NARCIS (Netherlands)

Slagter, Kirsten W; den Hartog, Laurens; Bakker, Nicolaas A; Vissink, Arjan; Meijer, Henny J A; Raghoebar, Gerry M

Background: Research interest on immediate placement of dental implants has shifted from implant survival toward optimal preservation of soft and hard tissues. The aim of this study is to systematically assess the condition of implant survival, peri-implant hard and soft tissue changes, esthetic

Fracture zones constrained by neutral surfaces in a fault-related fold: Insights from the Kelasu tectonic zone, Kuqa Depression

Science.gov (United States)

Sun, Shuai; Hou, Guiting; Zheng, Chunfang

2017-11-01

Stress variation associated with folding is one of the controlling factors in the development of tectonic fractures, however, little attention has been paid to the influence of neutral surfaces during folding on fracture distribution in a fault-related fold. In this study, we take the Cretaceous Bashijiqike Formation in the Kuqa Depression as an example and analyze the distribution of tectonic fractures in fault-related folds by core observation and logging data analysis. Three fracture zones are identified in a fault-related fold: a tensile zone, a transition zone and a compressive zone, which may be constrained by two neutral surfaces of fold. Well correlation reveals that the tensile zone and the transition zone reach the maximum thickness at the fold hinge and get thinner in the fold limbs. A 2D viscoelastic stress field model of a fault-related fold was constructed to further investigate the mechanism of fracturing. Statistical and numerical analysis reveal that the tensile zone and the transition zone become thicker with decreasing interlimb angle. Stress variation associated with folding is the first level of control over the general pattern of fracture distribution while faulting is a secondary control over the development of local fractures in a fault-related fold.

Optimization of External Envelope Insulation Thickness: A Parametric Study

Directory of Open Access Journals (Sweden)

Eleftheria Touloupaki

2017-02-01

Full Text Available Almost four years after the implementation deadline of the energy performance of buildings Directive recast (2010/31/EU and after being referred to the Court of Justice of the EU by the European Commission, Greece has not yet proceeded with the necessary calculations and legislative measures on the minimum, cost-optimal energy performance requirements for buildings. This paper aims to identify the optimal thickness of insulation that is cost-effective to apply in urban multi-family domestic buildings in the four climate zones of Greece. A reference building is selected in order to perform calculations over ten scenarios of external insulation thickness for each climate zone on a basic and three sensitivity analysis calculations according to the EU comparative methodology framework. The resulting energy savings for each insulation scenario are calculated, and then the cost-effectiveness of the measure is examined in financial and macroeconomic perspective for an economic lifecycle of 30 years. The results demonstrate the inadequacy of the national regulation’s current insulation limits and the externalities (funding gaps that need to be addressed in order to achieve the effective improvement of energy efficiency in Greek homes.

Immediate provisional restoration of a single-tooth implant in the esthetic zone: A case report

Directory of Open Access Journals (Sweden)

Po-Sung Fu

2011-02-01

Full Text Available Immediate implant restoration of single implants may demonstrate a positive effect on peri-implant soft tissue. Placement of a provisional restoration following implant surgery can create soft tissue contours that resemble normal gingival topography before placement of the definitive prosthesis. This article describes a staged approach of the mandibular permanent right central incisor, which was congenital missing. The proper space for restoration of the missing incisor was created through orthodontic treatment. The scheduled implant site was reconstructed using autogenous bone harvested from the chin region. After a healing period of four months, an implant was installed with the connection of a fixed provisional crown to a prefabricated temporary abutment. The soft tissue around the implant healed according to the contours of the provisional restoration and the emergence profile was used to duplicate the definitive restoration. Peri-implant esthetics was achieved through the staged approach and immediate restoration of the implant.

Immediate Regrafting of the Split Thickness Skin Graft Donor Site Assists Healing.

Science.gov (United States)

Bradow, Brian P; Hallock, Geoffrey G; Wilcock, Samuel P

2017-05-01

Delayed or even lack of healing of a split-thickness skin graft (STSG) donor site is a potential problem with elderly patients or those with poor wound healing capabilities. A proactive solution that may minimize this risk is to regraft that donor site using otherwise discarded skin graft remnants. A prospective, nonrandomized, consecutive study was designed to compare the time to healing of the commonly used anterior thigh STSG donor site in patients who had routine dressings (n = 113) versus those with comorbidities known to adversely affect wound healing and had planned regrafting (n = 204). Those comorbidities included age (≥65 years), diabetes mellitus, peripheral vascular disease, chronic renal disease, and chronic steroid use. The average number of comorbidities in the regrafted subgroup versus those not regrafted was 1.41 and 0.31, respectively. This was considered to be a significant difference ( P skin graft materials when so indicated and can be a proactive solution to a potentially cumbersome dilemma.

Effect of intermediate zone during gamma-gamma and X-ray spectrum logging of quarry wells with inversive probes

International Nuclear Information System (INIS)

Artsybashev, V.A.; Volkov, A.A.

1981-01-01

Experimental and calculated data on the effect of intermediate zone on results of gamma-gamma and X-ray spectrum logging of quarry wells at chalcopyrite deposits are presented. The measurements have been carried out using 57 Co and 109 Cd sources for intermediate zone represented by water, air and mud. Requirements for technical conditions of wells have been formulated. According to the requirements the application of gamma- gamma method is possible when the thickness of the intermediate zone does not exceed several millimetres and that of X-ray spectrum method - when the thickness does not exceed several hundredths of a millimetre [ru

A Model of Ischemia-Induced Neuroblast Activation in the Adult Subventricular Zone

OpenAIRE

Vergni, Davide; Castiglione, Filippo; Briani, Maya; Middei, Silvia; Alberdi, Elena; Reymann, Klaus G.; Natalini, Roberto; Volont?, Cinzia; Matute, Carlos; Cavaliere, Fabio

2009-01-01

12 p. We have developed a rat brain organotypic culture model, in which tissue slices contain cortex-subventricular zone-striatum regions, to model neuroblast activity in response to in vitro ischemia. Neuroblast activation has been described in terms of two main parameters, proliferation and migration from the subventricular zone into the injured cortex. We observed distinct phases of neuroblast activation as is known to occur after in vivo ischemia. Thus, immediately after oxygen/glucose...

Isotope studies of a thick unsaturated zone in a semi-arid area of Southern Africa

International Nuclear Information System (INIS)

Butler, M.J.; Verhagen, B.Th.

2001-01-01

Unsaturated zone profiles ranging in depth from 8 m to 22 m were obtained by hand augering an aeolian sand cover in the southern reaches of the semi-arid Kalahari thirstland. Moisture contents were rather low (<3 wt.%); in situ moisture chloride concentrations, measured by selective ion electrode following elutriation, are generally <500 ppm. Deuterium in the moisture was measured mass spectrometrically by direct quantitative conversion to hydrogen on zinc metal of moist soil samples. A novel technique of direct equilibration was developed for oxygen-18 analysis. Neither a thermonuclear tritium peak nor a stable isotope evaporation inversion near the surface could be observed in any of the profiles. Remarkable differences both laterally and vertically are observed in most parameters measured between profiles taken a few tens of metres apart. At greater depths, these differences become less pronounced. Recharge estimates based on chloride differ markedly from those obtained from tritium. Although the stable isotope values of the underlying saturated zone are similar to moisture in the deeper sections of the unsaturated zone profiles, the markedly lower chloride concentrations point towards preferential or bypass flow as an important mechanism of ground water recharge in the area. This can be regarded as a benchmark site on account of the wealth of unsaturated zone data as well as the detailed and ongoing rainfall record. (author)

Diffusional mass transport phenomena in the buffer material and damaged zone of a borehole wall in an underground nuclear fuel waste vault

International Nuclear Information System (INIS)

Page, S.; Cheung, S.C.H.

1983-06-01

The effects of the geometry of the borehole and the characteristics of the damaged borehole rock wall on the movement of the radionuclides from an underground nuclear waste vault have been studied. The results show that radionuclide transport will occur mainly through the buffer into the damaged zone of the borehole wall. As the degree of facturing of the damaged zone increases, the total radionuclide flux will increase up to a limit which can be approximated by a one-dimensional radial diffusion model. For large degrees of fracturing of the damaged zone, an increase in the radial buffer material thickness will decrease the total flux, whereas, for small degrees of fracturing, an increase in the radial buffer thickness may slightly increase the total flux. Increasing the vertical buffer thickness will significantly decrease the total flux when the degree of fracturing of the damaged zone is small. An increase in the vertical extent of the damaged zone will cause an increase in total flux

Cortical thickness changes correlate with cognition changes after cognitive training: Evidence from a Chinese community study

Directory of Open Access Journals (Sweden)

Lijuan eJiang

2016-05-01

Full Text Available The aim of this study was to investigate whether changes in cortical thickness correlated with cognitive function changes in healthy older adults after receiving cognitive training interventions. Moreover, it also aimed to examine the differential impacts of a multi-domain and a single-domain cognitive training interventions. Longitudinal magnetic resonance imaging (MRI scanning was performed on participants 65 to 75 years of age using the Siemens 3.0 T Trio Tim with the MPRAGE sequence. The cortical thickness was determined using FreeSurfer software. Cognitive functioning was evaluated using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS. There were significant group × time interaction effects on the left supramarginal, the left frontal pole cortical regions; and a marginal significant group × time interaction effects on visuospatial/constructional and delayed memory scores. In a multi-domain cognitive training group, a number of cortical region changes were significantly positively correlated with changes in attention, delayed memory, and the total score, but significantly negatively correlated with changes in immediate memory and language scores. In the single-domain cognitive training group, some cortical region changes were significantly positively associated with changes in immediate memory, delayed memory, and the total score, while they were significantly negatively associated with changes in visuospatial/constructional, language, and attention scores. Overall, multi-domain cognitive training offered more advantages in visuospatial/constructional, attention, and delayed memory abilities, while single-domain cognitive training benefited immediate memory ability more effectively. These findings suggest that healthy older adults benefit more from the multi-domain cognitive training than single-domain cognitive training. Cognitive training has impacted on cortical thickness changes in healthy elderly

Topographical Variation of Human Femoral Articular Cartilage Thickness, T1rho and T2 Relaxation Times Is Related to Local Loading during Walking.

Science.gov (United States)

Van Rossom, Sam; Wesseling, Mariska; Van Assche, Dieter; Jonkers, Ilse

2018-01-01

Objective Early detection of degenerative changes in the cartilage matrix composition is essential for evaluating early interventions that slow down osteoarthritis (OA) initiation. T1rho and T2 relaxation times were found to be effective for detecting early changes in proteoglycan and collagen content. To use these magnetic resonance imaging (MRI) methods, it is important to document the topographical variation in cartilage thickness, T1rho and T2 relaxation times in a healthy population. As OA is partially mechanically driven, the relation between these MRI-based parameters and localized mechanical loading during walking was investigated. Design MR images were acquired in 14 healthy adults and cartilage thickness and T1rho and T2 relaxation times were determined. Experimental gait data was collected and processed using musculoskeletal modeling to identify weight-bearing zones and estimate the contact force impulse during gait. Variation of the cartilage properties (i.e., thickness, T1rho, and T2) over the femoral cartilage was analyzed and compared between the weight-bearing and non-weight-bearing zone of the medial and lateral condyle as well as the trochlea. Results Medial condyle cartilage thickness was correlated to the contact force impulse ( r = 0.78). Lower T1rho, indicating increased proteoglycan content, was found in the medial weight-bearing zone. T2 was higher in all weight-bearing zones compared with the non-weight-bearing zones, indicating lower relative collagen content. Conclusions The current results suggest that medial condyle cartilage is adapted as a long-term protective response to localized loading during a frequently performed task and that the weight-bearing zone of the medial condyle has superior weight bearing capacities compared with the non-weight-bearing zones.

Increased supraspinatus tendon thickness following fatigue loading in rotator cuff tendinopathy: potential implications for exercise therapy

OpenAIRE

McCreesh, Karen M; Purtill, Helen; Donnelly, Alan E; Lewis, Jeremy S

2017-01-01

Background/aim Exercise imparts a load on tendon tissue that leads to changes in tendon properties. Studies suggest that loading immediately reduces tendon thickness, with a loss of this response in symptomatic tendinopathy. No studies investigating the response of tendon dimensions to load for the rotator cuff tendons exist. This study aimed to examine the short-term effect of loading on the thickness of the supraspinatus tendon and acromiohumeral distance those with and without rotator cuff...

78 FR 63381 - Safety Zones; Hawaiian Island Commercial Harbors, HI

Science.gov (United States)

2013-10-24

...; Kaumalapau, Lanai; Kahului, Maui and Kawaihae and Hilo on the Island of Hawaii). The purpose of these safety... the piers faces. (9) All waters of Hilo Harbor, Hawaii immediately adjacent to commercial piers 1 and.... SUMMARY: The Coast Guard is establishing nine (9) permanent safety zones encompassing Hawaii's commercial...

Immediate Implant Placement in Sockets with Asymptomatic Apical Periodontitis.

Science.gov (United States)

Crespi, Roberto; Capparé, Paolo; Crespi, Giovanni; Lo Giudice, Giuseppe; Gastaldi, Giorgio; Gherlone, Enrico

2017-02-01

The purpose of the present study was to evaluate if the presence of granulation tissue in asymptomatic apical periodontitis compromised immediate implant placement. Patients requiring extraction of one tooth (maxillary and mandibular incisive, canine or premolar) with asymptomatic apical periodontitis, were recruited for this prospective study. They were randomly scheduled into two groups: in first group (A) including 30 teeth, reactive soft tissue was debrided before implant placement, and in second group (B) including 30 teeth, reactive soft tissue was left in the apical lesion. Implants were positioned immediately after tooth extraction, and were loaded after 3 months in both groups. Cone beam computed tomography was performed before tooth extraction and at 1-year follow-up to evaluate the radiolucency around the root apex and the implant, bucco-lingual bone levels were also checked. Sixty patients were included in this study. Sixty implants were placed immediately after tooth extraction and, at 1-year follow-up, a survival rate of 100% was reported. After one year both groups showed absence of radiolucent zone at the apical region of implants. All fresh sockets presented a buccal-palatal bone reduction in both groups after one year, even if not statistically significant differences were found between baseline bone levels and within groups. Within the limitations of the present study, the immediate placement of implants into the extraction sockets with asymptomatic apical periodontitis, in presence of primary stability, did not lead to an increased rate of complications and rendered an equally favorable type of tissue integration. © 2016 Wiley Periodicals, Inc.

Imaging megathrust zone and Yakutat/Pacific plate interface in Alaska subduction zone

Science.gov (United States)

Kim, Y.; Abers, G. A.; Li, J.; Christensen, D. H.; Calkins, J. A.

2013-05-01

We image the subducted slab underneath a 450 km long transect of the Alaska subduction zone. Dense stations in southern Alaska are set up to investigate (1) the geometry and velocity structure of the downgoing plate and their relation to slab seismicity, and (2) the interplate coupled zone where the great 1964 (magnitude 9.3) had greatest rupture. The joint teleseismic migration of two array datasets (MOOS, Multidisciplinary Observations of Onshore Subduction, and BEAAR, Broadband Experiment Across the Alaska Range) based on teleseismic receiver functions (RFs) using the MOOS data reveal a shallow-dipping prominent low-velocity layer at ~25-30 km depth in southern Alaska. Modeling of these RF amplitudes shows a thin (<6.5 km) low-velocity layer (shear wave velocity of ~3 km/s), which is ~20-30% slower than normal oceanic crustal velocities, between the subducted slab and the overriding North American plate. The observed low-velocity megathrust layer (with P-to-S velocity ratio (Vp/Vs) exceeding 2.0) may be due to a thick sediment input from the trench in combination of elevated pore fluid pressure in the channel. The subducted crust below the low-velocity channel has gabbroic velocities with a thickness of 11-12 km. Both velocities and thickness of the low-velocity channel abruptly increase as the slab bends in central Alaska, which agrees with previously published RF results. Our image also includes an unusually thick low-velocity crust subducting with a ~20 degree dip down to 130 km depth at approximately 200 km inland beneath central Alaska. The unusual nature of this subducted segment has been suggested to be due to the subduction of the Yakutat terrane. We also show a clear image of the Yakutat and Pacific plate subduction beneath the Kenai Peninsula, and the along-strike boundary between them at megathrust depths. Our imaged western edge of the Yakutat terrane, at 25-30 km depth in the central Kenai along the megathrust, aligns with the western end of the

Coastal zone

International Nuclear Information System (INIS)

2002-01-01

The report entitled Climate Change Impacts and Adaptation : A Canadian Perspective, presents a summary of research regarding the impacts of climate change on key sectors over the past five years as it relates to Canada. This chapter on the coastal zone focuses on the impact of climate change on Canada's marine and Great Lakes coasts with tips on how to deal with the impacts associated with climate change in sensitive environments. This report is aimed at the sectors that will be most affected by adaptation decisions in the coastal zone, including fisheries, tourism, transportation and water resources. The impact of climate change in the coastal zone may include changes in water levels, wave patterns, storm surges, and thickness of seasonal ice cover. The Intergovernmental Panel on Climate Change projects global average sea level will rise between 9 and 88 centimetres between 1990 to 2100, but not all areas of Canada will experience the same rate of future sea level change. The main physical impact would be shoreline change that could result in a range of biophysical and socio-economic impacts, some beneficial, some negative. The report focuses on issues related to infrastructure and communities in coastal regions. It is noted that appropriate human adaptation will play a vital role in reducing the extent of potential impacts by decreasing the vulnerability of average zone to climate change. The 3 main trends in coastal adaptation include: (1) increase in soft protection, retreat and accommodation, (2) reliance on technology such as geographic information systems to manage information, and (3) awareness of the need for coastal adaptation that is appropriate for local conditions. 61 refs., 7 figs

STEM Analysis of Caenorhabditis elegans muscle thick filaments: evidence for microdifferentiated substructures

Science.gov (United States)

Muller, S. A.; Haner, M.; Ortiz, I.; Aebi, U.; Epstein, H. F.

2001-01-01

In the thick filaments of body muscle in Caenorhabditis elegans, myosin A and myosin B isoforms and a subpopulation of paramyosin, a homologue of myosin heavy chain rods, are organized about a tubular core. As determined by scanning transmission electron microscopy, the thick filaments show a continuous decrease in mass-per-length (MPL) from their central zones to their polar regions. This is consistent with previously reported morphological studies and suggests that both their content and structural organization are microdifferentiated as a function of position. The cores are composed of a second distinct subpopulation of paramyosin in association with the alpha, beta, and gamma-filagenins. MPL measurements suggest that cores are formed from seven subfilaments containing four strands of paramyosin molecules, rather than the two originally proposed. The periodic locations of the filagenins within different regions and the presence of a central zone where myosin A is located, implies that the cores are also microdifferentiated with respect to molecular content and structure. This differentiation may result from a novel "induced strain" assembly mechanism based upon the interaction of the filagenins, paramyosin and myosin A. The cores may then serve as "differentiated templates" for the assembly of myosin B and paramyosin in the tapering, microdifferentiated polar regions of the thick filaments.

78 FR 11116 - Safety Zone; Mamaroneck Beach and Yacht Club Fireworks, Mamaroneck Harbor, Long Island Sound, NY

Science.gov (United States)

2013-02-15

... 1625-AA00 Safety Zone; Mamaroneck Beach and Yacht Club Fireworks, Mamaroneck Harbor, Long Island Sound... to establish a temporary safety zone on the navigable waters of Long Island Sound in the vicinity of... from a portion of Long Island Sound before, during, and immediately after the fireworks event. DATES...

Geophysical evidence for widespread reversely magnetised pyroclastics in the western Taupo Volcanic Zone (New Zealand)

International Nuclear Information System (INIS)

Soengkono, S.; Hochstein, M.P.; Smith, I.E.M.; Itaya, T.

1992-01-01

Low-altitude aeromagnetic data show that negative residual anomalies are widespread over the western Taupo Volcanic Zone, New Zealand. Paleomagnetic study of eight rhyolitic ignimbrite units and two lava flows which are exposed in this area, together with new K-Ar dates of four of the ignimbrite units, indicate that the two lava units and seven of the ignimbrite units were erupted during the Matuyama geomagnetic epoch (>0.73 Ma B.P.) and suggest that rhyolitic volcanism in the western Taupo Volcanic Zone began as early as 1.6 Ma B.P. These results provide the basis for an interpretation of our aeromagnetic data which confirms the hypothesis that the magnetic anomalies observed in the western Taupo Volcanic Zone are caused by widespread, thick, reversely magnetised pyroclastic and lava flows. Magnetic modelling also allows thickness estimates of the younger, normally magnetised cover rocks which reach a maximum thickness of the order of 0.5 km in the Mangakino area. The magnetic structure of these volcanic rocks defines approximately the lateral extent of the Mangakino Volcanic Centre. (author). 41 refs., 2 figs., 3 tabs

Oxide thickness measurement for monitoring fuel performance at high burnup

International Nuclear Information System (INIS)

Jaeger, M.A.; Van Swam, L.F.P.; Brueck-Neufeld, K.

1991-01-01

For on-site monitoring of the fuel performance at high burnup, Advanced Nuclear Fuels uses the linear scan eddy current method to determine the oxide thickness of irradiated Zircaloy fuel cans. Direct digital data acquisition methods are employed to collect the data on magnetic storage media. This field-proven methodology allows oxide thickness measurements and rapid interpretation of the data during the reactor outages and makes it possible to immediately reinsert the assemblies for the next operating cycle. The accuracy of the poolside measurements and data acquisition/interpretation techniques have been verified through hot cell metallographic measurements of rods previously measured in the fuel pool. The accumulated data provide a valuable database against which oxide growth models have been benchmarked and allow for effective monitoring of fuel performance. (orig.) [de

Simulation and experimental determination of the macro-scale layer thickness distribution of electrodeposited Cu-line patterns on a wafer substrate

DEFF Research Database (Denmark)

Pantleon, Karen; Bossche, Bart van den; Purcar, Marius

2005-01-01

The impact of adjacent patterned zones with different active area densities on the current density and electrodeposited layer thickness distribution over a wafer substrate is examined, both by experiment and numerical simulation. The experiments consist in running an acid copper plating process o......) approach to compute the current density distribution over the electrodes. Experimental and computed layer thickness distributions are in very good agreement.......The impact of adjacent patterned zones with different active area densities on the current density and electrodeposited layer thickness distribution over a wafer substrate is examined, both by experiment and numerical simulation. The experiments consist in running an acid copper plating process...... on the patterned wafer, and layer thickness measurements by means of X-ray fluorescence (XRF) and atomic force microscopy (AFM). The simulations are based on a potential model approach taking into account electrolyte ohmic drop and electrode polarization effects, combined to a boundary element method (BEM...

19 CFR 146.70 - Transfer of zone-restricted merchandise into Customs territory.

Science.gov (United States)

2010-04-01

... transportation and exportation, for warehousing pending exportation, for destruction (except destruction of distilled spirits, wines and fermented malt liquors), for transfer from one zone to another, or for delivery..., for immediate transportation without appraisement, or under any other provision of the Customs laws...

On use of weld zone temperatures for online monitoring of weld quality in friction stir welding of naturally aged aluminium alloys

International Nuclear Information System (INIS)

Imam, Murshid; Biswas, Kajal; Racherla, Vikranth

2013-01-01

Highlights: • FSWs for 6063-T4 AA are done at different process parameters and sheet thicknesses. • Weld nugget zone and heat affected zone temperatures are monitored for each case. • Microstructural and mechanical characterisation of welds is done in all cases. • Weld ductility is found to be particularly sensitive to weld zone temperatures. • Strong correlation is found between WNZ and HAZ temperatures and weld properties. - Abstract: 6063-T4 aluminium alloy sheets of 3 and 6 mm thicknesses were friction stir butt welded using a square tool pin at a wide range of tool rotational speeds. Properties of obtained welds were characterised using tensile tests, optical micrographs, X-ray diffraction, and transmission electron microscopy. Shape, size, and distribution of precipitates in weld zones, and strength and ductility of welds were seen to directly correlate with peak temperatures in weld nugget and heat affected zones, independent of sheet thickness. In addition, fluctuations in measured temperature profiles, for 3 mm sheets, were seen to correlate with an increase in scatter of weld nugget zone properties for 3 mm sheets. Optimal weld strength and ductility were obtained for peak weld nugget zone temperatures of around 450 °C and corresponding peak heat affected zone temperatures of around 360–380 °C. Results obtained suggest that, at least for naturally aged aluminium alloys, nature of temperature evolution and magnitudes of peak temperatures in weld nugget and heat affected zones provide information on uniformity of properties in weld zones, overaging of heat affected zones, and formation of tunnel defects from improper material mixing at low weld zone temperatures

Digital surfaces and thicknesses of selected hydrogeologic units of the Floridan aquifer system in Florida and parts of Georgia, Alabama, and South Carolina

Science.gov (United States)

Williams, Lester J.; Dixon, Joann F.

2015-01-01

Digital surfaces and thicknesses of selected hydrogeologic units of the Floridan aquifer system were developed to define an updated hydrogeologic framework as part of the U.S. Geological Survey Groundwater Resources Program. The dataset contains structural surfaces depicting the top and base of the aquifer system, its major and minor hydrogeologic units and zones, geophysical marker horizons, and the altitude of the 10,000-milligram-per-liter total dissolved solids boundary that defines the approximate fresh and saline parts of the aquifer system. The thicknesses of selected major and minor units or zones were determined by interpolating points of known thickness or from raster surface subtraction of the structural surfaces. Additional data contained include clipping polygons; regional polygon features that represent geologic or hydrogeologic aspects of the aquifers and the minor units or zones; data points used in the interpolation; and polygon and line features that represent faults, boundaries, and other features in the aquifer system.

Immediate versus Delayed Treatment in the Anterior Maxilla Using Single Implants with a Laser-Microtextured Collar: 3-Year Results of a Case Series on Hard- and Soft-Tissue Response and Esthetics.

Science.gov (United States)

Guarnieri, Renzo; Belleggia, Fabrizio; Grande, Maurizio

2016-02-01

To compare peri-implant marginal bone loss, soft tissue response, and esthetics following single immediate implant treatment (IIT) and delayed implant treatment (DIT) in the esthetic zone of the maxilla in well-selected patients. Adequate bone volume and ideal soft tissue level/contour were considered requirements for implant therapy, with additional prerequisites for IIT of residual alveolar bone wall integrity and a thick gingival biotype. IIT included immediate placement and provisionalization, while DIT included extraction socket preservation followed by implant placement and provisionalization 4 months later. Cortical bone levels and peri-implant mucosal conditions were evaluated at regular intervals. The esthetic outcome was objectively rated after 3 years using the pink esthetic score (PES) and white esthetic score (WES). Twelve patients received an immediate Laser-Lok® implant, and 13 patients received a delayed Laser-Lok® implant. No significant differences were found between the study groups regarding survival rate (100%). The mean bone level from the implant/abutment interface was 0.35 ± 0.18 mm for IIT and 0.42 ± 0.21 mm for DIT after 3 years (p > 0.05). Mesial and distal papillae remained stable over time in DIT. A tendency for regrowth of mesial and distal papillae was found following IIT (p esthetics, DIT and IIT with single Laser-Lok® implants in the anterior maxilla are comparable and predictable options for well-selected patients. © 2015 by the American College of Prosthodontists.

Thick film magnetic nanoparticulate composites and method of manufacture thereof

Science.gov (United States)

Ma, Xinqing (Inventor); Zhang, Yide (Inventor); Ge, Shihui (Inventor); Zhang, Zongtao (Inventor); Yan, Dajing (Inventor); Xiao, Danny T. (Inventor)

2009-01-01

Thick film magnetic/insulating nanocomposite materials, with significantly reduced core loss, and their manufacture are described. The insulator coated magnetic nanocomposite comprises one or more magnetic components, and an insulating component. The magnetic component comprises nanometer scale particles (about 1 to about 100 nanometers) coated by a thin-layered insulating phase. While the intergrain interaction between the immediate neighboring magnetic nanoparticles separated by the insulating phase provides the desired soft magnetic properties, the insulating material provides high resistivity, which reduces eddy current loss.

Load-Displacement Curves of Spot Welded, Bonded, and Weld-Bonded Joints for Dissimilar Materials and Thickness

Directory of Open Access Journals (Sweden)

E.A. Al-Bahkali

2011-12-01

Full Text Available Three-dimensional finite element models of spot welded, bonded and weld-bonded joints are developed using ABAQUS software. Each model consists of two strips with dissimilar materials and thickness and is subjected to an axial loading. The bonded and weld-bonded joints have specific adhesive thickness. A detailed experimental plan to define many properties and quantities such as, the elastic - plastic properties, modulus of elasticity, fracture limit, and properties of the nugget and heat affected zones are carried out. Experiments include standard testing of the base metal, the adhesive, the nugget and heat affected zone. They also include employing the indentation techniques, and ductile fracture limits criteria, using the special notch tests. Complete load-displacement curves are obtained for all joining models and a comparison is made to determine the best combination.

Vertical and horizontal extension of the oxygen minimum zone in the eastern South Pacific Ocean

Science.gov (United States)

Fuenzalida, Rosalino; Schneider, Wolfgang; Garcés-Vargas, José; Bravo, Luis; Lange, Carina

2009-07-01

Recent hydrographic measurements within the eastern South Pacific (1999-2001) were combined with vertically high-resolution data from the World Ocean Circulation Experiment, high-resolution profiles and bottle casts from the World Ocean Database 2001, and the World Ocean Atlas 2001 in order to evaluate the vertical and horizontal extension of the oxygen minimum zone (oxygen minimum zone to be 9.82±3.60×10 6 km 2 and 2.18±0.66×10 6 km 3, respectively. The oxygen minimum zone is thickest (>600 m) off Peru between 5 and 13°S and to about 1000 km offshore. Its upper boundary is shallowest (zone in some places. Offshore, the thickness and meridional extent of the oxygen minimum zone decrease until it finally vanishes at 140°W between 2° and 8°S. Moving southward along the coast of South America, the zonal extension of the oxygen minimum zone gradually diminishes from 3000 km (15°S) to 1200 km (20°S) and then to 25 km (30°S); only a thin band is detected at ˜37°S off Concepción, Chile. Simultaneously, the oxygen minimum zone's maximum thickness decreases from 300 m (20°S) to less than 50 m (south of 30°S). The spatial distribution of Ekman suction velocity and oxygen minimum zone thickness correlate well, especially in the core. Off Chile, the eastern South Pacific Intermediate Water mass introduces increased vertical stability into the upper water column, complicating ventilation of the oxygen minimum zone from above. In addition, oxygen-enriched Antarctic Intermediate Water clashes with the oxygen minimum zone at around 30°S, causing a pronounced sub-surface oxygen front. The new estimates of vertical and horizontal oxygen minimum zone distribution in the eastern South Pacific complement the global quantification of naturally hypoxic continental margins by Helly and Levin [2004. Global distribution of naturally occurring marine hypoxia on continental margins. Deep-Sea Research I 51, 1159-1168] and provide new baseline data useful for studies on the

Soft tissue behavior around dental implants placed in fresh extraction sockets and immediately restored in esthetic area: a preliminary short-term evaluation

Directory of Open Access Journals (Sweden)

Ronaldo Antonio BRESCOVITT

2017-08-01

Full Text Available Abstract Objective To assess the behavior of the peri-implant soft margin after immediate implant placement with immediate function, by (1 direct clinical measurements of peri-implant soft margin height and thickness, (2 measurements of peri-implant soft margin height on photographs and (3 the perception of dental professionals regarding the results considering esthetic parameters. Material and method The study included 8 patients with central or lateral incisors indicated to be extracted. Direct measurements of peri-implant soft margin height and thickness were done immediately before extraction (T0 and 1 (T1, 4 (T2, 8 (T3 and 12 (T4 months after the flapless insertion of the implant. Photographs were taken at the same time intervals. A questionnaire was filled in by implantology professionals regarding their visual perception of color and peri-implant soft margin architecture and harmony in the implant region using the photographs obtained at T4. Result The clinical results showed significant changes to the height of the peri-implant soft margin, but the photographic results did not show significant changes for this measurement. The thickness of the attached gingiva was maintained during all the observation period. Of the professionals interviewed, 35.2% noticed an altered peri-implant soft margin color of the implant region, 39.8% noticed a change in the peri-implant soft margin architecture and 12.5% noticed a change in the peri-implant soft margin harmony. Conclusion The soft tissues around immediate implants changed during this period, but did not affect the aesthetic outcome and in the opinion of professionals, the aesthetic results were satisfactory for these cases.

Two-zone elastic-plastic single shock waves in solids.

Science.gov (United States)

Zhakhovsky, Vasily V; Budzevich, Mikalai M; Inogamov, Nail A; Oleynik, Ivan I; White, Carter T

2011-09-23

By decoupling time and length scales in moving window molecular dynamics shock-wave simulations, a new regime of shock-wave propagation is uncovered characterized by a two-zone elastic-plastic shock-wave structure consisting of a leading elastic front followed by a plastic front, both moving with the same average speed and having a fixed net thickness that can extend to microns. The material in the elastic zone is in a metastable state that supports a pressure that can substantially exceed the critical pressure characteristic of the onset of the well-known split-elastic-plastic, two-wave propagation. The two-zone elastic-plastic wave is a general phenomenon observed in simulations of a broad class of crystalline materials and is within the reach of current experimental techniques.

78 FR 61937 - Safety Zone; Port of Galveston, Pelican Island Bridge Repair

Science.gov (United States)

2013-10-07

... Zone; Port of Galveston, Pelican Island Bridge Repair AGENCY: Coast Guard, DHS. ACTION: Temporary final... safety during the Pelican Island Bridge Repair Project. This action is necessary to protect public... barge will be placed under the Pelican Island Bridge; therefore immediate action is needed to protect...

Duodenal endoscopic full-thickness resection (with video).

Science.gov (United States)

Schmidt, Arthur; Meier, Benjamin; Cahyadi, Oscar; Caca, Karel

2015-10-01

Endoscopic resection of duodenal non-lifting adenomas and subepithelial tumors is challenging and harbors a significant risk of adverse events. We report on a novel technique for duodenal endoscopic full-thickness resection (EFTR) by using an over-the-scope device. Data of 4 consecutive patients who underwent duodenal EFTR were analyzed retrospectively. Main outcome measures were technical success, R0 resection, histologic confirmation of full-thickness resection, and adverse events. Resections were done with a novel, over-the-scope device (full-thickness resection device, FTRD). Four patients (median age 60 years) with non-lifting adenomas (2 patients) or subepithelial tumors (2 patients) underwent EFTR in the duodenum. All lesions could be resected successfully. Mean procedure time was 67.5 minutes (range 50-85 minutes). Minor bleeding was observed in 2 cases; blood transfusions were not required. There was no immediate or delayed perforation. Mean diameter of the resection specimen was 28.3 mm (range 22-40 mm). Histology confirmed complete (R0) full-thickness resection in 3 of 4 cases. To date, 2-month endoscopic follow-up has been obtained in 3 patients. In all cases, the over-the-scope clip was still in place and could be removed without adverse events; recurrences were not observed. EFTR in the duodenum with the FTRD is a promising technique that has the potential to spare surgical resections. Modifications of the device should be made to facilitate introduction by mouth. Prospective studies are needed to further evaluate efficacy and safety for duodenal resections. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Load capacity of a thick-walled cylinder with a radial hole

International Nuclear Information System (INIS)

Laczek, S.; Rys, J.; Zielinski, A.P.

2010-01-01

The paper deals with elastic-plastic analysis of the stress-strain state in the vicinity of a hole in a thick-walled cylindrical pressure vessel. The investigations have been inspired by the phenomenon of ductile fracture observed in a high-pressure reactor. Using finite element calculations, different failure criteria are proposed to aid design and control of high-pressure vessels with piping attachments. They are compared with suggestions of American (ASME) and European (EN) standards. A simple shakedown analysis of the structure is also presented. The local stress distribution near the hole results in a specific failure of the vessel. A plastic zone appears in the vicinity of the internal cylinder surface and propagates along the hole side. The vessel unloading can cause local reverse plasticity, which leads to plastic shakedown in the small zone and then to progressive ductile fracture in this zone. This is dangerous for the whole structure.

Estimating the Extent and Thickness of DNAPL within the A/M Area of the Savannah River Site

International Nuclear Information System (INIS)

Jackson, D.G.; Payne, T.H.; Looney, B.B.; Rossabi, J.

1996-01-01

The objective of this study is to refine the current conceptual model for the extent, character, and thickness of DNAPL contamination in the A/M Area. The evaluation is based upon historical records of operations and waste management and on detailed screening of historical groundwater concentrations against solubility limits. The topology of the Green Clay confining zone is used as the primary factor determining DNAPL pool thickness and resulting migration paths

Effect of skin graft thickness on scar development in a porcine burn model.

Science.gov (United States)

DeBruler, Danielle M; Blackstone, Britani N; McFarland, Kevin L; Baumann, Molly E; Supp, Dorothy M; Bailey, J Kevin; Powell, Heather M

2018-06-01

Animal models provide a way to investigate scar therapies in a controlled environment. It is necessary to produce uniform, reproducible scars with high anatomic and biologic similarity to human scars to better evaluate the efficacy of treatment strategies and to develop new treatments. In this study, scar development and maturation were assessed in a porcine full-thickness burn model with immediate excision and split-thickness autograft coverage. Red Duroc pigs were treated with split-thickness autografts of varying thickness: 0.026in. ("thin") or 0.058in. ("thick"). Additionally, the thin skin grafts were meshed and expanded at 1:1.5 or 1:4 to evaluate the role of skin expansion in scar formation. Overall, the burn-excise-autograft model resulted in thick, raised scars. Treatment with thick split-thickness skin grafts resulted in less contraction and reduced scarring as well as improved biomechanics. Thin skin autograft expansion at a 1:4 ratio tended to result in scars that contracted more with increased scar height compared to the 1:1.5 expansion ratio. All treatment groups showed Matrix Metalloproteinase 2 (MMP2) and Transforming Growth Factor β1 (TGF-β1) expression that increased over time and peaked 4 weeks after grafting. Burns treated with thick split-thickness grafts showed decreased expression of pro-inflammatory genes 1 week after grafting, including insulin-like growth factor 1 (IGF-1) and TGF-β1, compared to wounds treated with thin split-thickness grafts. Overall, the burn-excise-autograft model using split-thickness autograft meshed and expanded to 1:1.5 or 1:4, resulted in thick, raised scars similar in appearance and structure to human hypertrophic scars. This model can be used in future studies to study burn treatment outcomes and new therapies. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

Computer modelling of RF ablation in cortical osteoid osteoma: Assessment of the insulating effect of the reactive zone.

Science.gov (United States)

Irastorza, Ramiro M; Trujillo, Macarena; Martel Villagrán, Jose; Berjano, Enrique

2016-05-01

The aim was to study by computer simulations the insulating role of the reactive zone surrounding a cortical osteoid osteoma (OO) in terms of electrical and thermal performance during radiofrequency ablation (RFA). We modelled a cortical OO consisting of a nidus (10 mm diameter) enclosed by a reactive zone. The OO was near a layer of cortical bone 1.5 mm thick. Trabecular bone partially surrounds the OO and there was muscle around the cortical bone layer. We modelled RF ablations with a non-cooled-tip 17-gauge needle electrode (300 s duration and 90 °C target temperature). Sensitivity analyses were conducted assuming a reactive zone electrical conductivity value (σrz) within the limits of the cortical and trabecular bone, i.e. 0.02 S/m and 0.087 S/m, respectively. In this way we were really modelling the different degrees of osteosclerosis associated with the reactive zone. The presence of the reactive zone drastically reduced the maximum temperature reached outside it. The temperature drop was proportional to the thickness of the reactive zone: from 68 °C when it was absent to 44 °C when it is 7.5 mm thick. Higher nidus conductivity values (σn) implied higher temperatures, while lower temperatures meant higher σrz values. Changing σrz from 0.02 S/m to 0.087 S/m reduced lesion diameters from 2.4 cm to 1.8 cm. The computer results suggest that the reactive zone plays the role of insulator in terms of reducing the temperature in the surrounding area.

77 FR 11434 - Safety Zone; Patapsco River, Northwest and Inner Harbors, Baltimore, MD

Science.gov (United States)

2012-02-27

...-AA00 Safety Zone; Patapsco River, Northwest and Inner Harbors, Baltimore, MD AGENCY: Coast Guard, DHS... intended route immediately prior to, during, and following the scheduled towing evolution, vessel traffic... made to the maritime community via marine information broadcasts so mariners may adjust their plans...

Zebrafish cardiac muscle thick filaments: isolation technique and three-dimensional structure.

Science.gov (United States)

González-Solá, Maryví; Al-Khayat, Hind A; Behra, Martine; Kensler, Robert W

2014-04-15

To understand how mutations in thick filament proteins such as cardiac myosin binding protein-C or titin, cause familial hypertrophic cardiomyopathies, it is important to determine the structure of the cardiac thick filament. Techniques for the genetic manipulation of the zebrafish are well established and it has become a major model for the study of the cardiovascular system. Our goal is to develop zebrafish as an alternative system to the mammalian heart model for the study of the structure of the cardiac thick filaments and the proteins that form it. We have successfully isolated thick filaments from zebrafish cardiac muscle, using a procedure similar to those for mammalian heart, and analyzed their structure by negative-staining and electron microscopy. The isolated filaments appear well ordered with the characteristic 42.9 nm quasi-helical repeat of the myosin heads expected from x-ray diffraction. We have performed single particle image analysis on the collected electron microscopy images for the C-zone region of these filaments and obtained a three-dimensional reconstruction at 3.5 nm resolution. This reconstruction reveals structure similar to the mammalian thick filament, and demonstrates that zebrafish may provide a useful model for the study of the changes in the cardiac thick filament associated with disease processes. Copyright © 2014 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Multivariate statistical analysis to investigate the subduction zone parameters favoring the occurrence of giant megathrust earthquakes

Science.gov (United States)

Brizzi, S.; Sandri, L.; Funiciello, F.; Corbi, F.; Piromallo, C.; Heuret, A.

2018-03-01

The observed maximum magnitude of subduction megathrust earthquakes is highly variable worldwide. One key question is which conditions, if any, favor the occurrence of giant earthquakes (Mw ≥ 8.5). Here we carry out a multivariate statistical study in order to investigate the factors affecting the maximum magnitude of subduction megathrust earthquakes. We find that the trench-parallel extent of subduction zones and the thickness of trench sediments provide the largest discriminating capability between subduction zones that have experienced giant earthquakes and those having significantly lower maximum magnitude. Monte Carlo simulations show that the observed spatial distribution of giant earthquakes cannot be explained by pure chance to a statistically significant level. We suggest that the combination of a long subduction zone with thick trench sediments likely promotes a great lateral rupture propagation, characteristic of almost all giant earthquakes.

A viscoplastic shear-zone model for episodic slow slip events in oceanic subduction zones

Science.gov (United States)

Yin, A.; Meng, L.

2016-12-01

on the thickness, viscosity, and dynamic yield strength of the shear zone. Our model predicts a linear increase in slip with time during the landward motion and an exponential decrease in slip magnitude during the trenchward motion.

Seismological evidence for a localized mushy zone at the Earth?s inner core boundary

OpenAIRE

Tian, Dongdong; Wen, Lianxing

2017-01-01

Although existence of a mushy zone in the Earth?s inner core has been hypothesized several decades ago, no seismic evidence has ever been reported. Based on waveform modeling of seismic compressional waves that are reflected off the Earth?s inner core boundary, here we present seismic evidence for a localized 4?8?km thick zone across the inner core boundary beneath southwest Okhotsk Sea with seismic properties intermediate between those of the inner and outer core and of a mushy zone. Such a ...

U Plant Geographic Zone Cleanup Prototype

International Nuclear Information System (INIS)

Romine, L.D.; Leary, K.D.; Lackey, M.B.; Robertson, J.R.

2006-01-01

The U Plant geographic zone (UPZ) occupies 0.83 square kilometers on the Hanford Site Central Plateau (200 Area). It encompasses the U Plant canyon (221-U Facility), ancillary facilities that supported the canyon, soil waste sites, and underground pipelines. The UPZ cleanup initiative coordinates the cleanup of the major facilities, ancillary facilities, waste sites, and contaminated pipelines (collectively identified as 'cleanup items') within the geographic zone. The UPZ was selected as a geographic cleanup zone prototype for resolving regulatory, technical, and stakeholder issues and demonstrating cleanup methods for several reasons: most of the area is inactive, sufficient characterization information is available to support decisions, cleanup of the high-risk waste sites will help protect the groundwater, and the zone contains a representative cross-section of the types of cleanup actions that will be required in other geographic zones. The UPZ cleanup demonstrates the first of 22 integrated zone cleanup actions on the Hanford Site Central Plateau to address threats to groundwater, the environment, and human health. The UPZ contains more than 100 individual cleanup items. Cleanup actions in the zone will be undertaken using multiple regulatory processes and decision documents. Cleanup actions will include building demolition, waste site and pipeline excavation, and the construction of multiple, large engineered barriers. In some cases, different cleanup actions may be taken at item locations that are immediately adjacent to each other. The cleanup planning and field activities for each cleanup item must be undertaken in a coordinated and cohesive manner to ensure effective execution of the UPZ cleanup initiative. The UPZ zone cleanup implementation plan (ZCIP) [1] was developed to address the need for a fundamental integration tool for UPZ cleanup. As UPZ cleanup planning and implementation moves forward, the ZCIP is intended to be a living document that will

Immediate loading and customized restoration of a single implant in the maxillary esthetic zone : A clinical report

NARCIS (Netherlands)

den Hartog, Laurens; Raghoebar, Gerry M.; Stellingsma, Kees; Meijer, Henny J. A.

2009-01-01

The replacement of a single missing anterior tooth with an implant-supported crown Is a demanding therapy. This report describes a treatment in which an anterior maxillary implant was immediately restored with a provisional restoration. During the provisional phase, an optimal emergence profile was

Biomechanical corneal changes induced by different flap thickness created by femtosecond laser

Directory of Open Access Journals (Sweden)

Fabricio W. Medeiros

2011-01-01

Full Text Available OBJECTIVE: To evaluate the impact of the creation of corneal flaps at different thicknesses on the biomechanical properties of swine corneas. METHOD: Twelve swine eyes were obtained to form two groups: 100 μm flap thickness and 300 μm flap thickness. Each eye was submitted to the following examinations: raster topography to investigate corneal curvature alterations, ocular response analyzer to investigate corneal hysteresis change, optical coherence tomography to measure central corneal and flap thickness and sonic wave propagation velocity as a measure of stiffness, before and immediately after flap creation. After flap amputation, surface wave velocity measurements were repeated. RESULTS: Measured flap thicknesses were statistically different for thin and thick flap groups, with an average of 108.5 + 6.9 and 307.8 + 11.5 μm respectively. Hysteresis and corneal resistance factor did not change significantly after flap creation in the thin flap group. With thicker flaps, both parameters decreased significantly from 8.0 +1.0 to 5.1 +1.5 mmHg and from 8.2 + 1.6 to 4.1 +2.5 mmHg respectively. Simulated keratometry values increased in the thick flap group (from 39.5 + 1 D to 45.9+1.2 D after flap creation but not in the thin flap group (from 40.6 + 0.6 D to 41.4+ 1.0 D. Regarding surface wave velocity analysis, the surgical procedures induced statistically lower results in some positions. CONCLUSION: In the experimental conditions established by this model, thicker flaps presented a greater biomechanical impact on the cornea.

Analysis of crustal thickness and off-axis low-velocity zones at the Endeavour segment of the Juan de Fuca Ridge

Science.gov (United States)

Wells, A. E.; Hooft, E. E.; Toomey, D. R.; Wilcock, W. S.; Weekly, R. T.

2010-12-01

Construction of the oceanic crust is often thought to occur by delivery of melt from the mantle to the ridge axis that is both segment-centered and rise-centered. However, recent seismic studies at the fast-spreading East Pacific Rise show that mantle melt delivery can be skewed relative to the rise leading to off-axis delivery of melt. Furthermore foci of mantle melt delivery occur on a length-scale shorter than that of a ridge segment and the region of greater melt supply, as measured by crustal thickness, does not correspond to the segment center. We use seismic data from the intermediate-spreading Endeavour segment of the Juan de Fuca Ridge to investigate the spatial and temporal pattern of melt supply in this setting and whether off-axis delivery and transport of melt is a common occurrence. The Juan de Fuca Ridge has a transitional morphology characterized by fault-bounded ridges that parallel the spreading center. Previous models of the Endeavour segment inferred that the off-axis ridges are constructed during periods of enhanced magmatism and that these are separated by the remains of rift valleys generated during periods of reduced magmatism. This model may imply that crustal thickness should vary rapidly, with thicker crust beneath the off-axis ridges and thinner crust in between. Alternatively, on the basis of recent seismic reflection images of crustal magma bodies along the Juan de Fuca ridge this topography is thought to reflect magma-induced deformation resulting from feedbacks between the rheology of the crust above the magma sill and dike intrusion. In this case, short wavelength crustal thickness variations may not be present. The melting anomalies associated with various nearby seamount chains also influence processes along the Juan de Fuca Ridge. The seismic reflection work indicates that there is a ~40-km-wide plateau of greater crustal thickness (~0.5-1.0 km) at the center of the Endeavour segment that began forming about 0.7 Ma. The plateau

Towards a Detailed Seismic Structure of the Valley of Mexico's Xochimilco Lake Zone.

Science.gov (United States)

Rabade, S.; Sanchez-Sanchez, J.; Ayala Hernandez, M.; Macias, M. A.; Aguilar Calderon, L. A.; Alcántara, L.; Almora Mata, D.; Castro Parra, G.; Delgado, R.; Leonardo Suárez, M.; Molina Avila, I.; Mora, A.; Perez-Yanez, C.; Ruiz, A. L.; Sandoval, H.; Torres Noguez, M.; Vazquez Larquet, R.; Velasco Miranda, J. M.; Aguirre, J.; Ramirez-Guzmán, L.

2017-12-01

Six centuries of gradual, intentional sediment filling in the Xochimilco Lake Zone have drastically reduced the size of the lake. The basin structure and the lake's clay limits and thickness are poorly constrained, and yet, essential to explain the city's anomalous ground motion. Therefore, we conducted an experiment to define the 3D velocity model of Mexico's capital; the CDMX-E3D. The initial phase involved the deployment of a moving set of 18-broadband stations with an interstation distance of 500m over a period of 19 weeks. We collected the data and analyzed the results for the Xochimilco Lake Zone using H/V Spectral Ratios (Nakamura, 1989), which provided an improved fundamental period map of the region. Results show that periods in the former lake zone have larger variability than values previously estimated. In order to obtain group velocity maps at different periods, we estimated Green's functions from ambient noise cross-correlations following standard methodologies to invert Rayleigh wave travel times (Bensen et al., 2007). Preliminary result show very low-velocity zones (100 m/s) and thick sediment layers in most of the former Xochimilco Lake area. This Project was funded by the Secretaria de Ciencia, Tecnología e Innovación (SECITI) of Mexico City. Project SECITI/073/2016.

Relative Abundances of Calcite and Silica in Fracture Coatings as a Possible Indicator of Evaporation in a Thick Unsaturated Zone, Yucca Mountain, Nevada

Science.gov (United States)

Marshall, B. D.; Moscati, R. J.

2005-12-01

Yucca Mountain, a ridge of shallowly dipping, Miocene-age volcanic rocks in southwest Nevada, is the proposed site for a nuclear waste repository to be constructed in the 500- to 700-m-thick unsaturated zone (UZ). At the proposed repository, the 300-m-thick Topopah Spring Tuff welded unit (TSw) is overlain by approximately 30 m of nonwelded tuffs (PTn); the Tiva Canyon Tuff welded unit (TCw) overlies the PTn with a range in thickness from 0 to approximately 130 m at the site. The amount of water percolation through the UZ is low and difficult to measure directly, but local seepage into mined tunnels has been observed in the TCw. Past water seepage in the welded tuffs is recorded by widespread, thin (0.3 cm) coatings of calcite and silica on fracture surfaces and within cavities. Abundances of calcite and silica in the coatings were determined by X-ray microfluorescence mapping and subsequent multispectral image analysis of over 200 samples. The images were classified into constituent phases including opal-chalcedony-quartz (secondary silica) and calcite. In the TCw samples, the median calcite/silica ratio is 8; in the TSw samples within 35 m below the PTn, median calcite/silica falls to 2, perhaps reflecting an increase in soluble silica from the presence of glass in the nonwelded tuffs. In the deeper parts of the TSw, median calcite/silica reaches 100 and many samples contain no detectable secondary silica phase. Evaporation and changing pCO2 control precipitation of calcite from water percolating downward in the UZ, but precipitation of opal requires only evaporation. Calcite/silica ratios, therefore, can constrain the relative importance of evaporation in the UZ. Although calcite/silica values scatter widely within the TSw, reflecting the spatial variability of gas and water flow, average calcite/silica ratios increase with stratigraphic depth, indicating less evaporation at the deeper levels of the UZ. Coupled with the much smaller calcite/silica ratios

Full reflector thickness and isolation thickness on neutron transport

International Nuclear Information System (INIS)

Sakai, Tomohiro; Naito, Yoshitaka; Komuro, Yuichi.

1988-08-01

A method to determine ''full reflector thickness'' and ''isolation thickness'', which is utilized for criticality safety evaluation on nuclear fuel facilities, was proposed in this paper. Firstly, a calculation was tryed to obtain the two kinds of thicknesses from the result of criticality calculations for a specific case. Then, two simple equations which calculates the two kinds of thicknesses were made from the relation between reflector (or isolator) thickness and k eff , and one-group diffusion theory. Finally, we proposed a new method to determine the thicknesses. From the method we proposed, ''full reflector thickness'' and ''isolation thickness'' can be obtain using the equations and migration length of the reflector (or isolator) and infinite and effective multiplication factor of the fuel. (author)

Radial mixing of material in the asterodial zone

International Nuclear Information System (INIS)

Ruzmaikina, T.V.; Safronov, V.S.; Weidenschilling, S.J.

1989-01-01

The asteroid belt shows radial zoning of compositional structure. The most abundant types are successively S, C and P types from the inner to the outer parts of the main belt, and D type in the Trojan clouds. Boundaries between compositional zones are not sharp, but gradual transitions over scales ∼1 AU in semimajor axis. The authors examine processes for producing this structure before, during and after the accretion of asteroids. The initial structure is established by temperature and composition gradients in the turbulent solar nebula during the collapse of the presolar cloud. The radial scale of the zoning, comparable to the disk thickness, favors disk models with relatively low turbulent viscosity. Radial decay of solid bodies due to gas drag during settling to the central plane and planetesimal formation probably causes only a small degree of mixing, due to the systematic nature of drag-induced motions

Area, length and thickness conservation: Dogma or reality?

Science.gov (United States)

Moretti, Isabelle; Callot, Jean Paul

2012-08-01

The basic assumption of quantitative structural geology is the preservation of material during deformation. However the hypothesis of volume conservation alone does not help to predict past or future geometries and so this assumption is usually translated into bed length in 2D (or area in 3D) and thickness conservation. When subsurface data are missing, geologists may extrapolate surface data to depth using the kink-band approach. These extrapolations, preserving both thicknesses and dips, lead to geometries which are restorable but often erroneous, due to both disharmonic deformation and internal deformation of layers. First, the Bolivian Sub-Andean Zone case is presented to highlight the evolution of the concepts on which balancing is based, and the important role played by a decoupling level in enhancing disharmony. Second, analogue models are analyzed to test the validity of the balancing techniques. Chamberlin's excess area approach is shown to be on average valid. However, neither the length nor the thicknesses are preserved. We propose that in real cases, the length preservation hypothesis during shortening could also be a wrong assumption. If the data are good enough to image the decollement level, the Chamberlin excess area method could be used to compute the bed length changes.

Effects of immobilization on thickness of superficial zone of articular cartilage of patella in rats

Directory of Open Access Journals (Sweden)

Khadija Iqbal

2012-01-01

Conclusion: Each segment of superficial zone behaves differentially on immobilization and remobilization. Perhaps a much longer duration of remobilization is required to reverse changes of immobilization in articular cartilage and plays a significant role in knee joint movements.

Electrical Conductivity in the Vadose Zone beneath a Tamarisk Grove along the Virgin River in Nevada

Science.gov (United States)

Shillito, R.; Sueki, S.; Berli, M.; Healey, J. M.; Acharya, K.

2013-12-01

Thick tamarisk groves along river corridors of the Southwest can transpire vast quantities of water and, as an invasive species, compete with native plants for space and resources. It is hypothesized that tamarisk can outcompete other species by not only tolerating high soil salinity, but by increasing soil salinity due to transpiration of salt-rich near-surface groundwater. The goal of this study was to garner experimental evidence for salt accumulation around tamarisk trees in comparison with other species (mesquite) along the Virgin River near Riverside, NV. At the experimental site, electrical conductivity (EC), temperature (T), and volumetric water content (VWC) within the vadose zone were monitored using sensors at 20, 40, 60, 80 and 100 cm depth on 30-minute intervals within the tamarisk thicket where several mesquite trees are found. Nearby groundwater levels were monitored every 40 days. The 2012 - 2013 data reveal an unexpected EC profile between the surface and the groundwater table (average depth 100 cm). A crust was found within depressions on the surface with EC values as high as 18.8 mS/cm. In the vadose zone (0 to 80 cm depth), average EC values of 4.4 mS/cm were recorded. Most interestingly, in the capillary fringe immediately above the water table (80 to 100 cm depth) average EC values of only 1.25 mS/cm were found whereas the groundwater (>100 cm depth) showed considerably higher EC values averaging 8.8 mS/cm. Additionally, the surface beneath the tamarisk had double the EC as that beneath the mesquite. The contrast in the EC indicates an increase in the aquifer salinity, which may be due to leachate infiltration through the vadose zone concentrated by plant transpiration and direct deposition of saline tamarisk leaf litter and secretions onto the understory. Evapotranspiration and shedding of litter by the tamarisk accelerated the salinity concentrations in the uppermost part of the vadose zone. Ultimately, understanding the salinity regime as

Pulsations of white dwarf stars with thick hydrogen or helium surface layers

Energy Technology Data Exchange (ETDEWEB)

Cox, A.N.; Starrfield, S.G.; Kidman, R.B.; Pesnell, W.D.

1986-07-01

In order to see if there could be agreement between results of stellar evolution theory and those of nonradial pulsation theory, calculations of white dwarf models have been made for hydrogen surface masses of 10/sup -4/ solar masses. Earlier results indicated that surface masses greater than 10/sup -8/ solar masses would not allow nonradial pulsations, even though all the driving and damping is in surface layers only 10/sup -12/ of the mass thick. It is shown that the surface mass of hydrogen in the pulsating white dwarfs (ZZ Ceti variables) can be any value as long as it is thick enough to contain the surface convection zone. 10 refs., 6 figs.

A note on the effect of fault gouge thickness on fault stability

Science.gov (United States)

Byerlee, J.; Summers, R.

1976-01-01

At low confining pressure, sliding on saw cuts in granite is stable but at high pressure it is unstable. The pressure at which the transition takes place increases if the thickness of the crushed material between the sliding surfaces is increased. This experimental result suggests that on natural faults the stability of sliding may be affected by the width of the fault zone. ?? 1976.

Strength-toughness requirements for thick walled high pressure vessels

International Nuclear Information System (INIS)

Kapp, J.A.

1990-01-01

The strength and toughness requirements of materials for use in high pressure vessels has been the subject of some discussion in the meetings of the Materials Task Group of the Special Working Group High Pressure Vessels. A fracture mechanics analysis has been performed to theoretically establish the required toughness for a high pressure vessel. This paper reports that the analysis performed is based on the validity requirement for plane strain fracture of fracture toughness test specimens. This is that at the fracture event, the crack length, uncracked ligament, and vessel length must each be greater than fifty times the crack tip plastic zone size for brittle fracture to occur. For high pressure piping applications, the limiting physical dimension is the uncracked ligament, as it can be assumed that the other dimensions are always greater than fifty times the crack tip plastic zone. To perform the fracture mechanics analysis several parameters must be known: these include vessel dimensions, material strength, degree of autofrettage, and design pressure. Results of the analysis show, remarkably, that the effects of radius ratio, pressure and degree of autofrettage can be ignored when establishing strength and toughness requirements for code purposes. The only parameters that enter into the calculation are yield strength, toughness and vessel thickness. The final results can easily be represented as a graph of yield strength against toughness on which several curves, one for each vessel thickness, are plotted

Relationship between side necking and plastic zone size at fracture

International Nuclear Information System (INIS)

Kim, Do Hyung; Kang, Ki Ju; Kim, Dong Hak

2004-01-01

Generally, fracture of a material is influenced by plastic zone size developed near the crack tip. Hence, according to the relative size of plastic zone in the material, the mechanics as a tool for analyzing the fracture process are classified into three kinds, that is, Linear Elastic Fracture Mechanics, Elastic Plastic Fracture Mechanics, Large Deformation Fracture Mechanics. Even though the plastic zone size is such an important parameter, the practical measurement techniques are very limited and the one for in-situ measurement is not virtually available. Therefore, elastic-plastic FEA has been performed to estimate the plastic zone size. In this study, it is noticed that side necking at the surface is a consequence of plastic deformation and lateral contraction and the relation between the plastic zone and side necking is investigated. FEA for modified boundary layer models with finite thickness, various mode mixes 0 .deg., 30 deg., 60 deg., 90 .deg. and strain hardening exponent n=3, 10 are performed. The results are presented and the implication regarding to application to experiment is discussed

Use of high-resolution ultrasound to measure changes in plantar fascia thickness resulting from tissue creep in runners and walkers.

Science.gov (United States)

Welk, Aaron B; Haun, Daniel W; Clark, Thomas B; Kettner, Norman W

2015-01-01

This study sought to use high-resolution ultrasound to measure changes in plantar fascia thickness as a result of tissue creep generated by walking and running. Independent samples of participants were obtained. Thirty-six walkers and 25 runners walked on a treadmill for 10 minutes or ran for 30 minutes, respectively. Standardized measures of the thickness of the plantar fascia were obtained in both groups using high-resolution ultrasound. The mean thickness of the plantar fascia was measured immediately before and after participation. The mean plantar fascia thickness was decreased by 0.06 ± 0.33 mm SD after running and 0.03 ± 0.22 mm SD after walking. The difference between groups was not significant. Although the parameters of this study did not produce significant changes in the plantar fascia thickness, a slightly higher change in the mean thickness of the plantar fascia in the running group deserves further investigation. Copyright © 2015 National University of Health Sciences. Published by Elsevier Inc. All rights reserved.

The crustal thickness of Australia

Science.gov (United States)

Clitheroe, G.; Gudmundsson, O.; Kennett, B.L.N.

2000-01-01

We investigate the crustal structure of the Australian continent using the temporary broadband stations of the Skippy and Kimba projects and permanent broadband stations. We isolate near-receiver information, in the form of crustal P-to-S conversions, using the receiver function technique. Stacked receiver functions are inverted for S velocity structure using a Genetic Algorithm approach to Receiver Function Inversion (GARFI). From the resulting velocity models we are able to determine the Moho depth and to classify the width of the crust-mantle transition for 65 broadband stations. Using these results and 51 independent estimates of crustal thickness from refraction and reflection profiles, we present a new, improved, map of Moho depth for the Australian continent. The thinnest crust (25 km) occurs in the Archean Yilgarn Craton in Western Australia; the thickest crust (61 km) occurs in Proterozoic central Australia. The average crustal thickness is 38.8 km (standard deviation 6.2 km). Interpolation error estimates are made using kriging and fall into the range 2.5-7.0 km. We find generally good agreement between the depth to the seismologically defined Moho and xenolith-derived estimates of crustal thickness beneath northeastern Australia. However, beneath the Lachlan Fold Belt the estimates are not in agreement, and it is possible that the two techniques are mapping differing parts of a broad Moho transition zone. The Archean cratons of Western Australia appear to have remained largely stable since cratonization, reflected in only slight variation of Moho depth. The largely Proterozoic center of Australia shows relatively thicker crust overall as well as major Moho offsets. We see evidence of the margin of the contact between the Precambrian craton and the Tasman Orogen, referred to as the Tasman Line. Copyright 2000 by the American Geophysical Union.

75 FR 32855 - Safety Zone; Pierce County, WA, Department of Emergency Management, Regional Water Exercise

Science.gov (United States)

2010-06-10

...-AA00 Safety Zone; Pierce County, WA, Department of Emergency Management, Regional Water Exercise AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Pierce County, Washington, Department of... immediate action is necessary to ensure safety of participants in the Pierce County Regional Water Rescue...

Designing for Immediate Play

DEFF Research Database (Denmark)

Pichlmair, Martin; Mech, Lena; Sicart, Miguel Angel

2017-01-01

This paper is concerned with designing for immediate play, the experience that a player has when joining a game designed for being played without particular preparation. Museum games, urban games, casual sports, and ad-hoc multiplayer video games are kinds of games that facilitate immediate play...... offer using examples and expert opinions. While most practices and game examples mentioned in this paper are from non-digital games, a special focus is put on the role of technology in immediately playable experiences. Still, the examined design dimensions are independent of the technological foundation...... of the game. This paper provides a starting point for designing better immediate play situations....

Vapor deposition on doublet airfoil substrates: Control of coating thickness and microstructure

Energy Technology Data Exchange (ETDEWEB)

Rodgers, Theron M.; Zhao, Hengbei; Wadley, Haydn N. G., E-mail: haydn@virginia.edu [Department of Materials Science and Engineering, University of Virginia, 395 McCormick Rd., P.O. Box 400745, Charlottesville, Virginia 22904 (United States)

2015-11-15

Gas jet assisted vapor deposition processes for depositing coatings are conducted at higher pressures than conventional physical vapor deposition methods, and have shown promise for coating complex shaped substrates including those with non-line-of-sight (NLS) regions on their surface. These regions typically receive vapor atoms at a lower rate and with a wider incident angular distribution than substrate regions in line-of-sight (LS) of the vapor source. To investigate the coating of such substrates, the thickness and microstructure variation along the inner (curved) surfaces of a model doublet airfoil containing both LS and NLS regions has been investigated. Results from atomistic simulations and experiments confirm that the coating's thickness is thinner in flux-shadowed regions than in other regions for all the coating processes investigated. They also indicated that the coatings columnar microstructure and pore volume fraction vary with surface location through the LS to NLS transition zone. A substrate rotation strategy for optimizing the thickness over the entire doublet airfoil surface was investigated, and led to the identification of a process that resulted in only small variation of coating thickness, columnar growth angle, and pore volume fraction on all doublet airfoil surfaces.

Study of the thickness evolution during SPT Testing

Directory of Open Access Journals (Sweden)

David Sánchez-Ávila

2018-03-01

Full Text Available The Small Punch Test (SPT is an increasingly expanding test used to obtain different mechanical data, such as strength, fracture, creep, etc…especially when there is little material available. However, the SPT test is more complicated than the uniaxial tensile test due to its non-linearity, which makes it difficult to relate the data obtained with the tensile tests. In fact, in the literature there is no clear model linking these tests and a different calibration should be used for each material. The complication of the SPT test is that the reduction of the sample thickness is not homogeneous in its gauge volume. In this work we proceeded to determine the variation of the SPT specimen thickness at several points, especially at the center and at the rupture zone, by means of the use of finite elements in COMSOL, taking a SLM AM (selective laser melting additive manufactured 316L stainless steel as the base material for modelling. For the appropriate modelling in COMSOL, the mechanical parameters of two 316L extreme thermomechanical treatments have been implemented, one annealed to a minimum hardness and another heavily work-hardened. The sample thickness variation results allow advancing in the theoretical modeling of the SPT behavior in order to obtain more accurate correlations with tensile tests data.

Mapping the mantle transition zone beneath the central Mid-Atlantic Ridge using Ps receiver functions.

Science.gov (United States)

Agius, M. R.; Rychert, C.; Harmon, N.; Kendall, J. M.

2017-12-01

Determining the mechanisms taking place beneath ridges is important in order to understand how tectonic plates form and interact. Of particular interest is establishing the depth at which these processes originate. Anomalies such as higher temperature within the mantle transition zone may be inferred seismically if present. However, most ridges are found in remote locations beneath the oceans restricting seismologists to use far away land-based seismometers, which in turn limits the imaging resolution. In 2016, 39 broadband ocean-bottom seismometers were deployed across the Mid-Atlantic Ridge, along the Romanche and Chain fracture zones as part of the PI-LAB research project (Passive Imaging of the Lithosphere and Asthenosphere Boundary). The one-year long seismic data is now retrieved and analysed to image the mantle transition zone beneath the ridge. We determine P-to-s (Ps) receiver functions to illuminate the 410- and 660-km depth mantle discontinuities using the extended multitaper deconvolution. The data from ocean-bottom seismometers have tilt and compliance noise corrections and is filtered between 0.05-0.2 Hz to enhance the signal. 51 teleseismic earthquakes generated hundreds of good quality waveforms, which are then migrated to depth in 3-D. The topography at the d410 deepens towards the west of the Romanche and Chain fracture zone by 15 km, whereas the topography of d660 shallows beneath the ridge between the two zones. Transition zone thickness thins from 5 to 20 km. Thermal anomalies determined from temperature relationships with transition zone thickness and depth variations of the d410 and d660 suggests hotter temperatures of about 200 K. Overall, the result suggests mid-ocean ridges may have associated thermal signatures as deep as the transition zone.

High Power Laser Beam Welding of Thick-walled Ferromagnetic Steels with Electromagnetic Weld Pool Support

Science.gov (United States)

Fritzsche, André; Avilov, Vjaceslav; Gumenyuk, Andrey; Hilgenberg, Kai; Rethmeier, Michael

The development of modern high power laser systems allows single pass welding of thick-walled components with minimal distortion. Besides the high demands on the joint preparation, the hydrostatic pressure in the melt pool increases with higher plate thicknesses. Reaching or exceeding the Laplace pressure, drop-out or melt sagging are caused. A contactless electromagnetic weld support system was used for laser beam welding of thick ferromagnetic steel plates compensating these effects. An oscillating magnetic field induces eddy currents in the weld pool which generate Lorentz forces counteracting the gravity forces. Hysteresis effects of ferromagnetic steels are considered as well as the loss of magnetization in zones exceeding the Curie temperature. These phenomena reduce the effective Lorentz forces within the weld pool. The successful compensation of the hydrostatic pressure was demonstrated on up to 20 mm thick plates of duplex and mild steel by a variation of the electromagnetic power level and the oscillation frequency.

Mapping Inherited Fractures in the Critical Zone Using Seismic Anisotropy From Circular Surveys

Science.gov (United States)

Novitsky, Christopher G.; Holbrook, W. Steven; Carr, Bradley J.; Pasquet, Sylvain; Okaya, David; Flinchum, Brady A.

2018-04-01

Weathering and hydrological processes in Earth's shallow subsurface are influenced by inherited bedrock structures, such as bedding planes, faults, joints, and fractures. However, these structures are difficult to observe in soil-mantled landscapes. Steeply dipping structures with a dominant orientation are detectable by seismic anisotropy, with fast wave speeds along the strike of structures. We measured shallow ( 2-4 m) seismic anisotropy using "circle shots," geophones deployed in a circle around a central shot point, in a weathered granite terrain in the Laramie Range of Wyoming. The inferred remnant fracture orientations agree with brittle fracture orientations measured at tens of meters depth in boreholes, demonstrating that bedrock fractures persist through the weathering process into the shallow critical zone. Seismic anisotropy positively correlates with saprolite thickness, suggesting that inherited bedrock fractures may control saprolite thickness by providing preferential pathways for corrosive meteoric waters to access the deep critical zone.

Applicability of spectral indices on thickness identification of oil slick

Science.gov (United States)

Niu, Yanfei; Shen, Yonglin; Chen, Qihao; Liu, Xiuguo

2016-10-01

Hyperspectral remote sensing technology has played a vital role in the identification and monitoring of oil spill events, and amount of spectral indices have been developed. In this paper, the applicability of six frequently-used indices is analyzed, and a combination of spectral indices in aids of support vector machine (SVM) algorithm is used to identify the oil slicks and corresponding thickness. The six spectral indices are spectral rotation (SR), spectral absorption depth (HI), band ratio of blue and green (BG), band ratio of BG and shortwave infrared index (BGN), 555nm and 645nm normalized by the blue band index (NB) and spectral slope (ND). The experimental study is conducted in the Gulf of Mexico oil spill zone, with Airborne Visible Infrared Imaging Spectrometer (AVIRIS) hyperspectral imagery captured in May 17, 2010. The results show that SR index is the best in all six indices, which can effectively distinguish the thickness of the oil slick and identify it from seawater; HI index and ND index can obviously distinguish oil slick thickness; BG, BGN and NB are more suitable to identify oil slick from seawater. With the comparison among different kernel functions of SVM, the classify accuracy show that the polynomial and RBF kernel functions have the best effect on the separation of oil slick thickness and the relatively pure seawater. The applicability of spectral indices of oil slick and the method of oil film thickness identification will in aids of oil/gas exploration and oil spill monitoring.

Application of InSAR and Gravimetry for Land Subsidence Hazard Zoning in Aguascalientes, Mexico

OpenAIRE

Pacheco-Martínez, Jesús; Cabral-Cano, Enrique; Wdowinski, Shimon; Hernández-Marín, Martín; Ortiz-Lozano, José; Zermeño-de-León, Mario

2015-01-01

In this work we present an application of InSAR and gravimetric surveys for risk management related to land subsidence and surface ground faulting generation. A subsidence velocity map derived from the 2007–2011 ALOS SAR imagery and a sediment thicknesses map obtained from the inversion of gravimetric data were integrated with a surface fault map to produce a subsidence hazard zoning in the city of Aguascalientes, Mexico. The resulting zoning is presented together with specific recommendation...

Phase zone plates as condensers for the Gottingen scanning x-ray microscope

International Nuclear Information System (INIS)

Hilkenbach, R.; Thieme

1987-01-01

With the Gottingen scanning x-ray microscope the synchrotron source is image by x-ray optics into a monochromatic small scan spot, through which a specimen can be moved. Hereby one part of the optics, the condenser zone plate and a pinhole, works as a linear monochromator in the wavelength region of λ = 2.36 nm to λ = 4.5 nm. The efficiency of such a condenser should be as high as possible to minimize the loss of radiation. Phase zone plates have a four times higher efficiency in the first order of diffraction than amplitude zone plates. Two condenser zone plates, KZP4 and KZP5, have been constructed so that they are well suited for the use in the scanning microscope. These zone plates have been made holographically by superposing two wavefronts of laser light in an specific designed optical arrangement and exposing the zone plate structure into a photoresist. Using reactive ion etching (RIE) the structure has been transformed into Germanium. The thickness of the zone plate has been chosen to show at λ = 2.36 nm a phase effect. The efficiency has been measured at the Berliner Elektronenspeircherring Gesellschaft fur Synchrotronstrahlung m.b.H., Berlin

Study of Shell Zone Formation in Lithographic and Anodizing Quality Aluminum Alloys: Experimental and Numerical Approach

Science.gov (United States)

Brochu, Christine; Larouche, André; Hark, Robert

Shell thickness is an important quality factor for lithographic and anodizing quality aluminum alloys. Increasing pressure is placed on casting plants to produce a thinner shell zone for these alloys. This study, based on plant trials and mathematical modelling highlights the most significant parameters influencing shell zone formation. Results obtained show the importance of metal temperature and distribution and mould metal level on shell zone formation. As an answer to specific plant problems, this study led to the development of improved metal distribution systems for DC casting of litho and anodizing quality alloys.

A first approach to calculate BIOCLIM variables and climate zones for Antarctica

Science.gov (United States)

Wagner, Monika; Trutschnig, Wolfgang; Bathke, Arne C.; Ruprecht, Ulrike

2018-02-01

For testing the hypothesis that macroclimatological factors determine the occurrence, biodiversity, and species specificity of both symbiotic partners of Antarctic lecideoid lichens, we present a first approach for the computation of the full set of 19 BIOCLIM variables, as available at http://www.worldclim.org/ for all regions of the world with exception of Antarctica. Annual mean temperature (Bio 1) and annual precipitation (Bio 12) were chosen to define climate zones of the Antarctic continent and adjacent islands as required for ecological niche modeling (ENM). The zones are based on data for the years 2009-2015 which was obtained from the Antarctic Mesoscale Prediction System (AMPS) database of the Ohio State University. For both temperature and precipitation, two separate zonings were specified; temperature values were divided into 12 zones (named 1 to 12) and precipitation values into five (named A to E). By combining these two partitions, we defined climate zonings where each geographical point can be uniquely assigned to exactly one zone, which allows an immediate explicit interpretation. The soundness of the newly calculated climate zones was tested by comparison with already published data, which used only three zones defined on climate information from the literature. The newly defined climate zones result in a more precise assignment of species distribution to the single habitats. This study provides the basis for a more detailed continental-wide ENM using a comprehensive dataset of lichen specimens which are located within 21 different climate regions.

Formation of disorder aluminium zones in an immiscible lead-aluminium system

International Nuclear Information System (INIS)

Huang, R Z; Zhang, L H; Sui, M L; Wang, Y M

2004-01-01

High resolution transmission electron microscopy (HRTEM) observations show evidence for the formation of disorder Al zones around some faceted Pb inclusions embedded in an Al matrix in immiscible lead-aluminium samples, which were prepared by a melt-spun method and then aged for about two months at room temperature. Furthermore, it is found that, both before and after ageing, all such Pb inclusions have a cube-cube orientation relationship with the Al matrix. The results of molecular dynamics (MD) simulations give an extensive analysis of the formation of the disorder Al zones and provide a reasonable explanation for the HRTEM finding: the existence of oxygen soluted in the Pb inclusions at higher temperatures may lead to the formation of the disorder Al zone in the aged sample. The dependence of the thickness of the disorder Al zone on the amount of oxygen soluted in the Pb inclusion at higher temperatures, and the average stress in the equilibrium configuration of a MD cell, is discussed

Replacement of a hopeless maxillary central incisor: a technique for the fabrication of an immediate implant-supported interim restoration.

Science.gov (United States)

Graiff, Lorenzo; Vigolo, Paolo

2012-04-01

Placement of a dental implant and an interim restoration in the esthetic zone immediately following tooth extraction is now a common procedure. However, in such clinical situations, the fabrication of an appropriate interim restoration may be challenging. The aim of this article is to present a technique for modifying the extracted tooth so it can be used as an implant-supported interim restoration.

Common Modality Effects in Immediate Free Recall and Immediate Serial Recall

Science.gov (United States)

Grenfell-Essam, Rachel; Ward, Geoff; Tan, Lydia

2017-01-01

In 2 experiments, participants were presented with lists of between 2 and 12 words for either immediate free recall (IFR) or immediate serial recall (ISR). Auditory recall advantages at the end of the list (modality effects) and visual recall advantages early in the list (inverse modality effects) were observed in both tasks and the extent and…

Crustal structure and mantle transition zone thickness beneath a hydrothermal vent at the ultra-slow spreading Southwest Indian Ridge (49°39'E): a supplementary study based on passive seismic receiver functions

Science.gov (United States)

Ruan, Aiguo; Hu, Hao; Li, Jiabiao; Niu, Xiongwei; Wei, Xiaodong; Zhang, Jie; Wang, Aoxing

2017-06-01

As a supplementary study, we used passive seismic data recorded by one ocean bottom seismometer (OBS) station (49°41.8'E) close to a hydrothermal vent (49°39'E) at the Southwest Indian Ridge to invert the crustal structure and mantle transition zone (MTZ) thickness by P-to-S receiver functions to investigate previous active seismic tomographic crustal models and determine the influence of the deep mantle thermal anomaly on seafloor hydrothermal venting at an ultra-slow spreading ridge. The new passive seismic S-wave model shows that the crust has a low velocity layer (2.6 km/s) from 4.0 to 6.0 km below the sea floor, which is interpreted as partial melting. We suggest that the Moho discontinuity at 9.0 km is the bottom of a layer (2-3 km thick); the Moho (at depth of 6-7 km), defined by active seismic P-wave models, is interpreted as a serpentinized front. The velocity spectrum stacking plot made from passive seismic data shows that the 410 discontinuity is depressed by 15 km, the 660 discontinuity is elevated by 18 km, and a positive thermal anomaly between 182 and 237 K is inferred.

Water-induced convection in the Earth's mantle transition zone

Science.gov (United States)

Richard, Guillaume C.; Bercovici, David

2009-01-01

Water enters the Earth's mantle by subduction of oceanic lithosphere. Most of this water immediately returns to the atmosphere through arc volcanism, but a part of it is expected as deep as the mantle transition zone (410-660 km depth). There, slabs can be deflected and linger before sinking into the lower mantle. Because it lowers the density and viscosity of the transition zone minerals (i.e., wadsleyite and ringwoodite), water is likely to affect the dynamics of the transition zone mantle overlying stagnant slabs. The consequences of water exchange between a floating slab and the transition zone are investigated. In particular, we focus on the possible onset of small-scale convection despite the adverse thermal gradient (i.e., mantle is cooled from below by the slab). The competition between thermal and hydrous effects on the density and thus on the convective stability of the top layer of the slab is examined numerically, including water-dependent density and viscosity and temperature-dependent water solubility. For plausible initial water content in a slab (≥0.5 wt %), an episode of convection is likely to occur after a relatively short time delay (5-20 Ma) after the slab enters the transition zone. However, water induced rheological weakening is seen to be a controlling parameter for the onset time of convection. Moreover, small-scale convection above a stagnant slab greatly enhances the rate of slab dehydration. Small-scale convection also facilitates heating of the slab, which in itself may prolong the residence time of the slab in the transition zone.

Soils characterisation along ecological forest zones in the Eastern Himalayas

Science.gov (United States)

Simon, Alois; Dhendup, Kuenzang; Bahadur Rai, Prem; Gratzer, Georg

2017-04-01

Elevational gradients are commonly used to characterise vegetation patterns and, to a lesser extent, also to describe soil development. Furthermore, interactions between vegetation cover and soil characteristics are repeatedly observed. Combining information on soil development and easily to distinguish forest zones along elevational gradients, creates an added value for forest management decisions especially in less studied mountain regions. For this purpose, soil profiles along elevational gradients in the temperate conifer forests of Western and Central Bhutan, ranging from 2600-4000m asl were investigated. Thereby, 82 soil profiles were recorded and classified according to the World Reference Base for Soil Resources. Based on 19 representative profiles, genetic horizons were sampled and analysed. We aim to provide fundamental information on forest soil characteristics along these elevational transects. The results are presented with regard to ecological forest zones. The elevational distribution of the reference soil groups showed distinct distribution ranges for most of the soils. Cambisols were the most frequently recorded reference soil group with 58% of the sampled profiles, followed by Podzols in higher elevations, and Stagnosols, at intermediate elevations. Fluvisols occurred only at the lower end of the elevational transects and Phaeozems only at drier site conditions in the cool conifer dry forest zone. The humus layer thickness differs between forest zones and show a shift towards increased organic layer (O-layer) with increasing elevation. The reduced biomass productivity with increasing elevation and subsequently lower litter input compensates for the slow decomposition rates. The increasing O-layer thickness is an indicator of restrained intermixing of organic and mineral components by soil organisms at higher elevation. Overall, the soil types and soil characteristics along the elevational gradient showed a continuous and consistent change, instead

Deep and bottom water characteristics in the Owen Fracture Zone, Western Arabian Sea

Digital Repository Service at National Institute of Oceanography (India)

Naqvi, S.W.A.; Kureishy, T.W.

Hydro chemical studies at a station (10 degrees 34.l'N,56 degrees 31,7'E) in the Owen Fracture zone reveal an active movement of bottom water as approx 75 m thick, cold, low-salinity layer. Silicate profile exhibits a broad maximum coinciding with a...

Heat deposition, damage, and tritium breeding characteristics in thick liquid wall blanket concepts

International Nuclear Information System (INIS)

Youssef, M.Z.; Abdou, M.A.

2000-01-01

The advanced power extraction (APEX) study aims at exploring new and innovative blanket concepts that can efficiently extract power from fusion devices with high neutron wall load. Among the concepts under investigation is the free liquid FW/liquid blanket concept in which a fast flowing liquid FW (∼2-3 cm) is followed by thick flowing blanket (B) of ∼40-50 cm thickness with minimal amount of structure. The liquid FW/B are contained inside the vacuum vessel (VV) with a shielding zone (S) located either behind the VV and outside the vacuum boundary (case A) or placed after the FW/B and inside the VV (case B). In this paper we investigate the nuclear characteristics of this concept in terms of: (1) attenuation capability of the liquid FW/B/S and protection of the VV and magnet against radiation damage; (2) profiles of tritium production rate and tritium breeding ratio (TBR) for several liquid candidates; and (3) profiles of heat deposition rate and power multiplication. The candidate liquid breeders considered are Li, Flibe, Li-Sn, and Li-Pb. Parameters varied are (1) FW/B thickness, L, (2) Li-6 enrichment and (3) thickness of the shield

Rapakivi texture formation via disequilibrium melting in a contact partial melt zone, Antarctica

Science.gov (United States)

Currier, R. M.

2017-12-01

In the McMurdo Dry Valleys of Antarctica, a Jurassic aged dolerite sill induced partial melting of granite in the shallow crust. The melt zone can be traced in full, from high degrees of melting (>60%) along the dolerite contact, to no apparent signs of melting, 10s of meters above the contact. Within this melt zone, the well-known rapakivi texture is found, arrested in various stages of development. High above the contact, and at low degrees of melting, K-feldspar crystals are slightly rounded and unmantled. In the lower half of the melt zone, mantles of cellular textured plagioclase appear on K-feldspar, and thicken towards the contact heat source. At the highest degrees of melting, cellular-textured plagioclase completely replaces restitic K-feldspar. Because of the complete exposure and intact context, the leading models of rapakivi texture formation can be tested against this system. The previously proposed mechanisms of subisothermal decompression, magma-mixing, and hydrothermal exsolution all fail to adequately describe rapakivi generation in this melt zone. Preferred here is a closed system model that invokes the production of a heterogeneous, disequilibrium melt through rapid heating, followed by calcium and sodium rich melt reacting in a peritectic fashion with restitic K-feldspar crystals. This peritectic reaction results in the production of plagioclase of andesine-oligoclase composition—which is consistent with not just mantles in the melt zone, but globally as well. The thickness of the mantle is diffusion limited, and thus a measure of the diffusive length scale of sodium and calcium over the time scale of melting. Thermal modeling provides a time scale of melting that is consistent with the thickness of observed mantles. Lastly, the distribution of mantled feldspars is highly ordered in this melt zone, but if it were mobilized and homogenized—mixing together cellular plagioclase, mantled feldspars, and unmantled feldspars—the result would be

Probing the deep critical zone beneath the Luquillo Experimental Forest, Puerto Rico

Science.gov (United States)

Buss, Heather L.; Brantley, Susan L.; Scatena, Fred; Bazilevskaya, Katya; Blum, Alex E.; Schulz, Marjorie S.; Jiménez, Rafael; White, Arthur F.; Rother, G.; Cole, D.

2013-01-01

Recent work has suggested that weathering processes occurring in the subsurface produce the majority of silicate weathering products discharged to the world's oceans, thereby exerting a primary control on global temperature via the well-known positive feedback between silicate weathering and CO2. In addition, chemical and physical weathering processes deep within the critical zone create aquifers and control groundwater chemistry, watershed geometry and regolith formation rates. Despite this, most weathering studies are restricted to the shallow critical zone (e.g. soils, outcrops). Here we investigate the chemical weathering, fracturing and geomorphology of the deep critical zone in the Bisley watershed in the Luquillo Critical Zone Observatory, Puerto Rico, from two boreholes drilled to 37.2 and 27.0 m depth, from which continuous core samples were taken. Corestones exposed aboveground were also sampled. Weathered rinds developed on exposed corestones and along fracture surfaces on subsurface rocks slough off of exposed corestones once rinds attain a thickness up to ~1 cm, preventing the corestones from rounding due to diffusion limitation. Such corestones at the land surface are assumed to be what remains after exhumation of similar, fractured bedrock pieces that were observed in the drilled cores between thick layers of regolith. Some of these subsurface corestones are massive and others are highly fractured, whereas aboveground corestones are generally massive with little to no apparent fracturing. Subsurface corestones are larger and less fractured in the borehole drilled on a road where it crosses a ridge compared with the borehole drilled where the road crosses the stream channel. Both borehole profiles indicate that the weathering zone extends to well below the stream channel in this upland catchment; hence weathering depth is not controlled by the stream level within the catchment and not all of the water in the watershed is discharged to the stream

Thermochronometrically constrained anatomy and evolution of a Miocene extensional accommodation zone and tilt domain boundary: The southern Wassuk Range, Nevada

Science.gov (United States)

Gorynski, Kyle E.; Stockli, Daniel F.; Douglas Walker, J.

2013-06-01

(AHe) and Zircon (ZHe) (U-Th)/He thermochronometric data from the southern Wassuk Range (WR) coupled with 40Ar/39Ar age data from the overlying tilted Tertiary section are used to constrain the thermal evolution of an extensional accommodation zone and tilt-domain boundary. AHe and ZHe data record two episodes of rapid cooling related to the tectonic exhumation of the WR fault block beginning at ~15 and ~4 Ma. Extension was accommodated through fault-block rotation and variably tilted the southern WR to the west from ~60°-70° in the central WR to ~15°-35° in the southernmost WR and Pine Grove Hills, and minimal tilting in the Anchorite Hills and along the Mina Deflection to the south. Middle Miocene geothermal gradient estimates record heating immediately prior to large-magnitude extension that was likely coeval with the extrusion of the Lincoln Flat andesite at ~14.8 Ma. Geothermal gradients increase from ~19° ± 4°C/km to ≥ 65° ± 20°C/km toward the Mina Deflection, suggesting that it was the focus of Middle Miocene arc magmatism in the upper crust. The decreasing thickness of tilt blocks toward the south resulted from a shallowing brittle/ductile transition zone. Postmagmatic Middle Miocene extension and fault-block advection were focused in the northern and central WR and coincidentally moderated the large lateral thermal gradient within the uppermost crust.

Quantitative measurement of mean inner potential and specimen thickness from high-resolution off-axis electron holograms of ultra-thin layered WSe2.

Science.gov (United States)

Winkler, Florian; Tavabi, Amir H; Barthel, Juri; Duchamp, Martial; Yucelen, Emrah; Borghardt, Sven; Kardynal, Beata E; Dunin-Borkowski, Rafal E

2017-07-01

The phase and amplitude of the electron wavefunction that has passed through ultra-thin flakes of WSe 2 is measured from high-resolution off-axis electron holograms. Both the experimental measurements and corresponding computer simulations are used to show that, as a result of dynamical diffraction, the spatially averaged phase does not increase linearly with specimen thickness close to an [001] zone axis orientation even when the specimen has a thickness of only a few layers. It is then not possible to infer the local specimen thickness of the WSe 2 from either the phase or the amplitude alone. Instead, we show that the combined analysis of phase and amplitude from experimental measurements and simulations allows an accurate determination of the local specimen thickness. The relationship between phase and projected potential is shown to be approximately linear for extremely thin specimens that are tilted by several degrees in certain directions from the [001] zone axis. A knowledge of the specimen thickness then allows the electrostatic potential to be determined from the measured phase. By using this combined approach, we determine a value for the mean inner potential of WSe 2 of 18.9±0.8V, which is 12% lower than the value calculated from neutral atom scattering factors. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

19 CFR 10.101 - Immediate delivery.

Science.gov (United States)

2010-04-01

... 19 Customs Duties 1 2010-04-01 2010-04-01 false Immediate delivery. 10.101 Section 10.101 Customs... Importations § 10.101 Immediate delivery. (a) Shipments entitled to immediate delivery. Shipments consigned to... as shipments the immediate delivery of which is necessary within the purview of section 448(b...

Elastic thickness estimates at northeast passive margin of North America and its implications

Science.gov (United States)

Kumar, R. T. Ratheesh; Maji, Tanmay K.; Kandpal, Suresh Ch; Sengupta, D.; Nair, Rajesh R.

2011-06-01

Global estimates of the elastic thickness (Te) of the structure of passive continental margins show wide and varying results owing to the use of different methodologies. Earlier estimates of the elastic thickness of the North Atlantic passive continental margins that used flexural modelling yielded a Te value of ~20-100 km. Here, we compare these estimates with the Te value obtained using orthonormalized Hermite multitaper recovered isostatic coherence functions. We discuss how Te is correlated with heat flow distribution and depth of necking. The E-W segment in the southern study region comprising Nova Scotia and the Southern Grand Banks show low Te values, while the zones comprising the NE-SW zones, viz., Western Greenland, Labrador, Orphan Basin and the Northern Grand Bank show comparatively high Te values. As expected, Te broadly reflects the depth of the 200-400°C isotherm below the weak surface sediment layer at the time of loading, and at the margins most of the loading occurred during rifting. We infer that these low Te measurements indicate Te frozen into the lithosphere. This could be due to the passive nature of the margin when the loads were emplaced during the continental break-up process at high temperature gradients.

Use of well points to determine the thickness and extent of floating product atop the water table

International Nuclear Information System (INIS)

Liikala, T.L.; Lewis, R.; Gilmore, T.; Hoffmann, H.

1994-01-01

The release of petroleum products to the ground water is a widespread problem. Conventional plume tracking techniques are to drill wells and measure product thickness and extent. In this study, well points were installed to rapidly and inexpensively determine the thickness and extent of floating product atop the water table. Spills and leaks of JP-4 have produced a discrete full layer atop the water table at one site at Eielson Air Force Base near Fairbanks, Alaska. The 0.2- to 1.3-foot-thick layer was identified in two ground water monitoring wells at a depth of approximately 10 feet. The layer is contained within unconsolidated glaciofluvial sands and gravels. A comprehensive assessment of the product thickness and extent was necessary for the site remedial investigation/feasibility study. The emplacement of additional monitoring wells was discouraged because of time and budget constraints. The fuel layer was delineated with 18 screened well points. The points consist of 2-inch-diameter galvanized steel pipe. The points were driven into the floating products with a hollow-stem auger rig sampling hammer. The product thickness was measured with an interface probe. The presence of floating product could be measured immediately after emplacement; the product thickness measurements typically stabilized within three days. The product thickness compared favorably with those measured in adjacent monitoring wells

Teleseismic Investigations of the Malawi and Luangwa Rift Zones: Ongoing Observations From the SAFARI Experiment

Science.gov (United States)

Reed, C. A.; Gao, S. S.; Liu, K. H.; Yu, Y.; Chindandali, P. R. N.; Massinque, B.; Mdala, H. S.; Mutamina, D. M.

2015-12-01

In order to evaluate the influence of crustal and mantle heterogeneities upon the initiation of the Malawi rift zone (MRZ) and reactivation of the Zambian Luangwa rift zone (LRZ) subject to Cenozoic plate boundary stress fields and mantle buoyancy forces, we installed and operated 33 Seismic Arrays For African Rift Initiation (SAFARI) three-component broadband seismic stations in Malawi, Mozambique, and Zambia from 2012 to 2014. During the twenty-four month acquisition period, nearly 6200 radial receiver functions (RFs) were recorded. Stations situated within the MRZ, either along the coastal plains or within the Shire Graben toward the south, report an average crustal thickness of 42 km relative to approximately 46 km observed at stations located along the rift flanks. This implies the juvenile MRZ is characterized by a stretching factor not exceeding 1.1. Meanwhile, P-to-S velocity ratios within the MRZ increase from 1.71 to 1.82 in southernmost Malawi, indicating a substantial modification of the crust during Recent rifting. Time-series stacking of approximately 5500 RFs recorded by the SAFARI and 44 neighboring network stations reveals an apparent uplift of 10 to 15 km along both the 410- and 660-km mantle transition zone (MTZ) discontinuities beneath the MRZ and LRZ which, coupled with an apparently normal 250-km MTZ thickness, implies a first-order high-velocity contribution from thickened lithosphere. Preliminary manual checking of SAFARI shear-wave splitting (SWS) measurements provides roughly 650 high-quality XKS phases following a component re-orientation to correct station misalignments. Regional azimuthal variations in SWS fast orientations are observed, from rift-parallel in the vicinity of the LRZ to rift-oblique in the MRZ. A major 60° rotation in the fast orientation occurs at approximately 31°E, possibly resulting from the modulation of mantle flow around a relatively thick lithospheric keel situated between the two rift zones.

Interpretation of zircon coronae textures from metapelitic granulites of the Ivrea–Verbano Zone, northern Italy: two-stage decomposition of Fe–Ti oxides

Directory of Open Access Journals (Sweden)

E. Kovaleva

2017-07-01

Full Text Available In this study, we report the occurrence of zircon coronae textures in metapelitic granulites of the Ivrea–Verbano Zone. Unusual zircon textures are spatially associated with Fe–Ti oxides and occur as (1 vermicular-shaped aggregates 50–200 µm long and 5–20 µm thick and as (2 zircon coronae and fine-grained chains, hundreds of micrometers long and ≤ 1 µm thick, spatially associated with the larger zircon grains. Formation of such textures is a result of zircon precipitation during cooling after peak metamorphic conditions, which involved: (1 decomposition of Zr-rich ilmenite to Zr-bearing rutile, and formation of the vermicular-shaped zircon during retrograde metamorphism and hydration; and (2 recrystallization of Zr-bearing rutile to Zr-depleted rutile intergrown with quartz, and precipitation of the submicron-thick zircon coronae during further exhumation and cooling. We also observed hat-shaped grains that are composed of preexisting zircon overgrown by zircon coronae during stage (2. Formation of vermicular zircon (1 preceded ductile and brittle deformation of the host rock, as vermicular zircon is found both plastically and cataclastically deformed. Formation of thin zircon coronae (2 was coeval with, or immediately after, brittle deformation as coronae are found to fill fractures in the host rock. The latter is evidence of local, fluid-aided mobility of Zr. This study demonstrates that metamorphic zircon can nucleate and grow as a result of hydration reactions and mineral breakdown during cooling after granulite-facies metamorphism. Zircon coronae textures indicate metamorphic reactions in the host rock and establish the direction of the reaction front.

Quantitative measurement of mean inner potential and specimen thickness from high-resolution off-axis electron holograms of ultra-thin layered WSe{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Winkler, Florian, E-mail: f.winkler@fz-juelich.de [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons (ER-C), Forschungszentrum Jülich, D-52425 Jülich (Germany); Peter Grünberg Institute 5 (PGI-5), Forschungszentrum Jülich, D-52425 Jülich (Germany); Tavabi, Amir H. [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons (ER-C), Forschungszentrum Jülich, D-52425 Jülich (Germany); Peter Grünberg Institute 5 (PGI-5), Forschungszentrum Jülich, D-52425 Jülich (Germany); Barthel, Juri [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons (ER-C), Forschungszentrum Jülich, D-52425 Jülich (Germany); Gemeinschaftslabor für Elektronenmikroskopie (GFE), RWTH Aachen University, D-52074 Aachen (Germany); Duchamp, Martial [Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons (ER-C), Forschungszentrum Jülich, D-52425 Jülich (Germany); Peter Grünberg Institute 5 (PGI-5), Forschungszentrum Jülich, D-52425 Jülich (Germany); Yucelen, Emrah [FEI Company, Achtseweg Noord 5, Eindhoven 5600 KA (Netherlands); Borghardt, Sven; Kardynal, Beata E. [Peter Grünberg Institute 9 (PGI-9), Forschungszentrum Jülich, D-52425 Jülich (Germany); and others

2017-07-15

The phase and amplitude of the electron wavefunction that has passed through ultra-thin flakes of WSe{sub 2} is measured from high-resolution off-axis electron holograms. Both the experimental measurements and corresponding computer simulations are used to show that, as a result of dynamical diffraction, the spatially averaged phase does not increase linearly with specimen thickness close to an [001] zone axis orientation even when the specimen has a thickness of only a few layers. It is then not possible to infer the local specimen thickness of the WSe{sub 2} from either the phase or the amplitude alone. Instead, we show that the combined analysis of phase and amplitude from experimental measurements and simulations allows an accurate determination of the local specimen thickness. The relationship between phase and projected potential is shown to be approximately linear for extremely thin specimens that are tilted by several degrees in certain directions from the [001] zone axis. A knowledge of the specimen thickness then allows the electrostatic potential to be determined from the measured phase. By using this combined approach, we determine a value for the mean inner potential of WSe{sub 2} of 18.9±0.8 V, which is 12% lower than the value calculated from neutral atom scattering factors. - Highlights: • Quantitative analysis of high resolution electron holograms of WSe{sub 2}. • Local specimen thickness determination and estimation of tilt angle. • Mean inner potential evaluation of WSe2 avoiding dynamical diffraction.

CRUSTAL THICKNESS VARIATIONS AND SEISMICITY OF NORTHWESTERN SOUTH AMERICA

Directory of Open Access Journals (Sweden)

Woo Kim Jeong

2007-06-01

Full Text Available Any uncompensated mass of the northern Andes Mountains is presumably under pressure to adjust within the Earth to its ideal state of isostatic equilibrium. Isostasy is the ideal state that any
uncompensated mass seeks to achieve in time. These pressures interact with the relative motions between adjacent plates that give rise to earthquakes along the plate boundaries. By combining the
gravity MOHO estimates and crustal discontinuities with historical and instrumental seismological catalogs the correlation between isostatically disturbed terrains and seismicity has been established.
The thinner and thicker crustal regions were mapped from the zero horizontal curvature of the crustal thickness estimates. These boundaries or edges of crustal thickness variations were compared to
crustal discontinuities inferred from gravity and magnetic anomalies and the patterns of seismicity that have been catalogued for the last 363 years. The seismicity is very intense along the Nazca-North
Andes, Caribbean-North American and North Andes-South American collision zones and associated with regional tectonic compressional stresses that have locally increased and/or diminished by
compressional and tensional stress, respectively, due to crustal thickness variations. High seismicity is also associated with the Nazca-Cocos diverging plate boundary whereas low seismicity is associated with the Panama-Nazca Transform Fault and the South American Plate.

Bone demarcation of the temporomandibular joint. Validity of clinical assessment of bone thickness by means of CT

International Nuclear Information System (INIS)

Ahlqvist, J.B.; Isberg, A.M.

1998-01-01

Purpose: To study the CT depiction of bone demarcations in the temporomandibular joint, using conventional window level and window width; and to evaluate observer performance in estimating bone thickness in these images. Material and Methods: Seven joint specimens were imaged by CT and then cryosectioned. The measurements of bone wall thickness in the images were compared to the true bone thickness at each cutting level. In addition, 4 experienced radiologists estimated the thickness of the bone walls in the images. Results: The relative difference between the CT reproduction and the true bone thickness was small for bone walls thicker than 2 mm. This difference increased with the decrease in bone thickness and the increase in the inclination of the bone wall from the perpendicular to the image plane. Bone walls thinner than 1 mm were reproduced as considerably thicker than their true thickness. This resulted in a clinical overestimation of bone thickness. Conclusion: Both the CT representation and the interpretation of bone demarcation in the temporomandibular joint may constitute a problem. Partial volume averaging effects can result in an overestimation of bone dimensions amounting to 200% for thin bones. The central white zone in images of thin bone walls obtained with the parameters described here could serve as an indicator that could help to reduce the risk of overestimating bone thickness. (orig.)

ROCK MASS DAMAGED ZONE CAUSED BY BLASTING DURING TUNNEL EXCAVATION

Directory of Open Access Journals (Sweden)

Hrvoje Antičević

2012-07-01

Full Text Available Design of underground spaces, including tunnels, and repositories for radioactive waste include the application of the same or similar technologies. Tunnel excavation by blasting inevitably results in the damage in the rock mass around the excavation profile. The damage in the rock mass immediately next to the tunnel profile emerges as the expanding of the existing cracks and the appearance of new cracks, i.e. as the change of the physical and-mechanical properties of the rock mass. Concerning the design of deep geological repositories, requirements in terms of damaged rock are the same or more rigorous than for the design of tunnel. The aforementioned research is directed towards determining the depth of damage zone caused by blasting. The depth of the damage zone is determined by measuring the changes of physical and-mechanical properties of the rock mass around the tunnel excavation profile. By this research the drilling and blasting parameters were correlated with the depth and size of the damage zone (the paper is published in Croatian.

Choroidal thickness and myopia in relation to physical activity during childhood

DEFF Research Database (Denmark)

Lundberg, Kristian; Jacobsen, Nina; Vestergaard, Anders Højslet

Purpose: Decreasing physical activity (PA) has been suggested to be a driving force behind the rapid increase of myopia worldwide. The possible protective effects of PA might be through increased blood flow and subsequent change in thickness of the choroid. The purpose of this study......, L, M and V PA (2.31 µm/% (p=0.22), -3.99 µm/% (p=0.15), -5.43 µm/% (p=0.57) and -0.53 µm/% (p=0.95), respectively). Conclusions: We found no association between physical activity and the choroidal thickness, axial length or refractive error. However, the choroid was thinner in myopic eyes......±59 µm (3 mm zone), respectively. All CT measurements were thinner in myopic eyes (psex-adjusted linear regression there were no associations between PA and SE, AL or any CT measurements. There was no association between accumulated PA and the overall CT for SED...

Determination of a Critical Sea Ice Thickness Threshold for the Central Arctic Ocean

Science.gov (United States)

Ford, V.; Frauenfeld, O. W.; Nowotarski, C. J.

2017-12-01

While sea ice extent is readily measurable from satellite observations and can be used to assess the overall survivability of the Arctic sea ice pack, determining the spatial variability of sea ice thickness remains a challenge. Turbulent and conductive heat fluxes are extremely sensitive to ice thickness but are dominated by the sensible heat flux, with energy exchange expected to increase with thinner ice cover. Fluxes over open water are strongest and have the greatest influence on the atmosphere, while fluxes over thick sea ice are minimal as heat conduction from the ocean through thick ice cannot reach the atmosphere. We know that turbulent energy fluxes are strongest over open ocean, but is there a "critical thickness of ice" where fluxes are considered non-negligible? Through polar-optimized Weather Research and Forecasting model simulations, this study assesses how the wintertime Arctic surface boundary layer, via sensible heat flux exchange and surface air temperature, responds to sea ice thinning. The region immediately north of Franz Josef Land is characterized by a thickness gradient where sea ice transitions from the thickest multi-year ice to the very thin marginal ice seas. This provides an ideal location to simulate how the diminishing Arctic sea ice interacts with a warming atmosphere. Scenarios include both fixed sea surface temperature domains for idealized thickness variability, and fixed ice fields to detect changes in the ocean-ice-atmosphere energy exchange. Results indicate that a critical thickness threshold exists below 1 meter. The threshold is between 0.4-1 meters thinner than the critical thickness for melt season survival - the difference between first year and multi-year ice. Turbulent heat fluxes and surface air temperature increase as sea ice thickness transitions from perennial ice to seasonal ice. While models predict a sea ice free Arctic at the end of the warm season in future decades, sea ice will continue to transform

Global Patterns of Legacy Nitrate Storage in the Vadose Zone

Science.gov (United States)

Ascott, M.; Gooddy, D.; Wang, L.; Stuart, M.; Lewis, M.; Ward, R.; Binley, A. M.

2017-12-01

Global-scale nitrogen (N) budgets have been developed to quantify the impact of man's influence on the nitrogen cycle. However, these budgets often do not consider legacy effects such as accumulation of nitrate in the deep vadose zone. In this presentation we show that the vadose zone is an important store of nitrate which should be considered in future nitrogen budgets for effective policymaking. Using estimates of depth to groundwater and nitrate leaching for 1900-2000, we quantify for the first time the peak global storage of nitrate in the vadose zone, estimated as 605 - 1814 Teragrams (Tg). Estimates of nitrate storage are validated using previous national and basin scale estimates of N storage and observed groundwater nitrate data for North America and Europe. Nitrate accumulation per unit area is greatest in North America, China and Central and Eastern Europe where thick vadose zones are present and there is an extensive history of agriculture. In these areas the long solute travel time in the vadose zone means that the anticipated impact of changes in agricultural practices on groundwater quality may be substantially delayed. We argue that in these areas use of conventional nitrogen budget approaches is inappropriate and their continued use will lead to significant errors.

Plastic Zone Analysis of Deep-Buried, Noncircular Tunnel and Application on the High-Speed Railway in the Karst Area

Directory of Open Access Journals (Sweden)

Hai Shi

2017-01-01

Full Text Available With the conformal mapping function provided by Verruijt, the outland of a noncircular tunnel can be mapped to a circular unit in the complex plane and then spread the analytic function into a Laurent series. The stress unified solution of oval and horseshoe cross section can be determined using Muskhelishvili’s complex variables function method. Subsequently, the solution can be taken into the Griffith strength failure criterion and determine the scale and shape of plastic zone in the tunnel surrounding rock. Aiming at the critical safety thickness between a concealed cave and tunnel in the karst area and determining whether the plastic zone of tunnel surrounding rock is connected with the plastic zone of cave as a judgment standard, the model of critical safety thickness among the concealed caves and tunnels is established. The numerical model is established in comparison with the computing method of rock plate critical safety thickness in actual engineering based on the Doumo tunnel engineering of Shanghai-Kunming (Guizhou segment high-speed railway. The following conclusions can be drawn: the analytical approximation method has less indexes, and the output of this method is approximately close to actual engineering and numerical analysis, in which it is reliable and rational.

Recombination zone in white organic light emitting diodes with blue and orange emitting layers

Science.gov (United States)

Tsuboi, Taiju; Kishimoto, Tadashi; Wako, Kazuhiro; Matsuda, Kuniharu; Iguchi, Hirofumi

2012-10-01

White fluorescent OLED devices with a 10 nm thick blue-emitting layer and a 31 nm thick orange-emitting layer have been fabricated, where the blue-emitting layer is stacked on a hole transport layer. An interlayer was inserted between the two emitting layers. The thickness of the interlayer was changed among 0.3, 0.4, and 1.0 nm. White emission with CIE coordinates close to (0.33, 0.33) was observed from all the OLEDs. OLED with 0.3 nm thick interlayer gives the highest maximum luminous efficiency (11 cd/A), power efficiency (9 lm/W), and external quantum efficiency (5.02%). The external quantum efficiency becomes low with increasing the interlayer thickness from 0 nm to 1.0 nm. When the location of the blue- and orange-emitting layers is reversed, white emission was not obtained because of too weak blue emission. It is suggested that the electron-hole recombination zone decreases nearly exponentially with a distance from the hole transport layer.

Lead Thickness Measurements

International Nuclear Information System (INIS)

Rucinski, R.

1998-01-01

The preshower lead thickness applied to the outside of D-Zero's superconducting solenoid vacuum shell was measured at the time of application. This engineering documents those thickness measurements. The lead was ordered in sheets 0.09375-inch and 0.0625-inch thick. The tolerance on thickness was specified to be +/- 0.003-inch. The sheets all were within that thickness tolerance. The nomenclature for each sheet was designated 1T, 1B, 2T, 2B where the numeral designates it's location in the wrap and 'T' or 'B' is short for 'top' or 'bottom' half of the solenoid. Micrometer measurements were taken at six locations around the perimeter of each sheet. The width,length, and weight of each piece was then measured. Using an assumed pure lead density of 0.40974 lb/in 3 , an average sheet thickness was calculated and compared to the perimeter thickness measurements. In every case, the calculated average thickness was a few mils thinner than the perimeter measurements. The ratio was constant, 0.98. This discrepancy is likely due to the assumed pure lead density. It is not felt that the perimeter is thicker than the center regions. The data suggests that the physical thickness of the sheets is uniform to +/- 0.0015-inch.

The development and structure of thick-walled, multicellular, aerial spores in Diheterospora chlamydosporia (=Verticillium chlamydosporium).

Science.gov (United States)

Cambell, W P; Griffiths, D A

1975-07-01

The aerial, thick-walled spores in Diheterospara chlamydosporia arose as terminal swellings on erect hyphae. Repeated septation of the continuously swelling spore resulted in a multicellular structure. Immediately after the onset of septation secondary wall material was laid down between the two-layered primary wall and the plasmalemma. The presence of secondary wall material indicates that the multicellular spore is a dictyochlamydospore and not an aleuriospore. The relationship between chlamydospores and aleuriospores in other fungi is discussed.

Large scale multi-zone creep finite element modelling of a main steam line branch intersection

International Nuclear Information System (INIS)

Payten, Warwick

2006-01-01

A number of papers detail the non-linear creep finite element analysis of branch pieces. Predominately these models have incorporated only a single material zone representing the parent material. Multi-zone models incorporating weld material and heat affected zones have primarily been two-dimensional analyses, in part due to the large number of elements required to adequately represent all of the zones. This paper describes a non-linear creep analysis of a main steam line branch intersection using creep properties to represent the parent metal, weld metal, and heat affected zone (HAZ), the stress redistribution over 100,000 h is examined. The results show that the redistribution leads to a complex stress state, particularly at the heat affected zone. Although, there is damage on the external surface of the branch piece as expected, the results indicate that the damage would be more widespread through extensive sections of the heat affected zone. This would appear to indicate that the time between damage indications on the surface using techniques such as replication and full thickness damage may be more limited then previously expected

Short communication: Genetic characterization of digital cushion thickness.

Science.gov (United States)

Oikonomou, G; Banos, G; Machado, V; Caixeta, L; Bicalho, R C

2014-01-01

Dairy cow lameness is a serious animal welfare issue. It is also a significant cause of economic losses, reducing reproductive efficiency and milk production and increasing culling rates. The digital cushion is a complex structure composed mostly of adipose tissue located underneath the distal phalanx and has recently been phenotypically associated with incidence of claw horn disruption lesions (CHDL); namely, sole ulcers and white line disease. The objective of this study was to characterize digital cushion thickness genetically and to investigate its association with body condition score (BCS), locomotion score (LOCO), CHDL, and milk production. Data were collected from 1 large closely monitored commercial dairy farm located in upstate New York; 923 dairy cows were used. Before trimming, the following data were collected by a member of the research team: BCS, cow height measurement, and LOCO. Presence or not of CHDL (sole ulcer or white line disease, or both) was recorded at trimming. Immediately after the cows were hoof trimmed, they underwent digital sonographic B-mode examination for the measurement of digital cushion thickness. Factors such as parity number, stage of lactation, calving date, mature-equivalent 305-d milk yield (ME305MY), and pedigree information were obtained from the farm's dairy management software (DairyCOMP 305; Valley Agricultural Software, Tulare, CA). Univariate animal models were used to obtain variance component estimations for each studied trait (CHDL, BCS, digital cushion thickness average, LOCO, height, and ME305MY) and a 6-variate analysis was conducted to estimate the genetic, residual, and phenotypic correlations between the studied traits. The heritability estimate of DCTA was 0.33±0.09, whereas a statistically significant genetic correlation was estimated between DCTA and CHDL (-0.60±0.29). Of the other genetic correlations, significant estimates were derived for BCS with LOCO (-0.49±0.19) and ME305MY (-0.48±0.20). Digital

Solute travel time in the vadose zone under RWMC at INEL

International Nuclear Information System (INIS)

Liou, J.C.P.; Tian, J.

1995-01-01

Solute transport in the vadose zone under the Radioactive Waste Management Complex (RWMC) at the Idaho National Engineering Laboratory (INEL) is considered. The objective is to assess the relative importance of variables involved in modeling the travel time of a conservative solute from ground surface to water table. The vadose zone under RWMC is composed of several layers of basalt flows interceded with sediment layers. The thickness of the layers varies with location. The hydraulic properties also vary. The extents of the variations are large, with standard deviations exceed mean in some instances. The vadose zone is idealized as composed of horizontal layers. Solute transport starts at the ground surface and moves vertically downwards to the water table. The perceived process is one-dimensional. This study used VS2DT, a computer code developed by the US Geological Survey, for simulating solute transport in variably saturated porous media

Sediment Thickness and a WEST-EAST Geologic Cross Section in the Caracas Valley

OpenAIRE

KANTAK, PETER; SCHMITZ, MICHAEL; AUDEMARD, FRANCK

2005-01-01

Caracas is located at the Caribbean - South America plate boundary zone, with an associated strike slip fault system, which accommodates the relative movement of both plates and is responsible for the seismic hazard in the region. The damage pattern of the 1967 Caracas earthquake emphasized the existence of important site effects due to the sedimentary basin fill of the Caracas valley. A revised map of the sedimentary thickness was developed during this study, based on drill holes (mostly fro...

Beta-Zone parapapillary atrophy and the velocity of glaucoma progression.

Science.gov (United States)

Teng, Christopher C; De Moraes, Carlos Gustavo V; Prata, Tiago S; Tello, Celso; Ritch, Robert; Liebmann, Jeffrey M

2010-05-01

Beta-Zone parapapillary atrophy (PPA) occurs more commonly in eyes with glaucoma. Rates of glaucomatous visual field (VF) progression in eyes with and without beta-zone PPA at the time of baseline assessment were compared. Retrospective, comparative study. Two hundred forty-five patients from the New York Glaucoma Progression Study. Subjects with glaucomatous optic neuropathy and repeatable VF loss were assessed for eligibility. Eyes with a Heidelberg Retina Tomograph II (HRT) examination, at least 5 visual field tests after the HRT in either eye, optic disc photographs, and Zone PPA was defined as a region of chorioretinal atrophy with visible sclera and choroidal vessels adjacent to the optic disc. Global rates of VF progression were determined by automated pointwise linear regression analysis. Univariate analysis included age, gender, ethnicity, central corneal thickness (CCT), refractive error, baseline mean deviation, baseline intraocular pressure (IOP), mean IOP, IOP fluctuation, disc area, rim area, rim area-to-disc area ratio, beta-zone PPA area, beta-zone PPA area-to-disc area ratio, and presence or absence of beta-zone PPA. The relationship between beta-zone PPA and the rate and risk of glaucoma progression. Two hundred forty-five eyes of 245 patients (mean age, 69.6+/-12.3 years) were enrolled. The mean follow-up was 4.9+/-1.4 years and the mean number of VFs after HRT was 9.3+/-2.7. beta-Zone PPA was present in 146 eyes (65%). Eyes with beta-zone PPA progressed more rapidly (-0.84+/-0.8 dB/year) than eyes without it (-0.51+/-0.6 dB/year; Pzone PPA (HR, 2.59; P1.5 dB/year; P = 0.08) global rates of progression occurred more commonly in eyes with beta-zone PPA than in eyes without it. Thinner CCT (zone PPA (kappa = 0.13). Eyes with beta-zone PPA are at increased risk for glaucoma progression and warrant close clinical surveillance. Copyright 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Global variations in gravity-derived oceanic crustal thickness: Implications on oceanic crustal accretion and hotspot-lithosphere interactions

Science.gov (United States)

Lin, J.; Zhu, J.

2012-12-01

the relatively wide partial melting zones in the upper mantle beneath the fast and intermediately fast ridges might act as "buffer" zones, thus diluting the melt anomalies from the underlying hotspots or regions of mantle heterogeneities. (3) As the crustal age increases and the lithospheric plate thickens, regions of thickened crust start to develop on ocean basins that were originally created at fast and intermediately fast ridges. The integrated crustal volume for fast and intermediately fast ocean crust appears to reach peak values for certain geological periods, such as 40-50 Ma and 70-80 Ma. The newly constructed global models of gravity-derived crustal thickness, combining with geochemical and other constraints, can be used to investigate the processes of oceanic crustal accretion and hotspot-lithosphere interactions.

Mantle transition zone structure beneath the Canadian Shield

Science.gov (United States)

Thompson, D. A.; Helffrich, G. R.; Bastow, I. D.; Kendall, J. M.; Wookey, J.; Eaton, D. W.; Snyder, D. B.

2010-12-01

The Canadian Shield is underlain by one of the deepest and most laterally extensive continental roots on the planet. Seismological constraints on the mantle structure beneath the region are presently lacking due to the paucity of stations in this remote area. Presented here is a receiver function study on transition zone structure using data from recently deployed seismic networks from the Hudson Bay region. High resolution images based on high signal-to-noise ratio data show clear arrivals from the 410 km and 660 km discontinuities, revealing remarkably little variation in transition zone structure. Transition zone thickness is close to the global average (averaging 245 km across the study area), and any deviations in Pds arrival time from reference Earth models can be readily explained by upper-mantle velocity structure. The 520 km discontinuity is not a ubiquitous feature, and is only weakly observed in localised areas. These results imply that the Laurentian root is likely confined to the upper-mantle and if any mantle downwelling exists, possibly explaining the existence of Hudson Bay, it is also confined to the upper 400 km. Any thermal perturbations at transition zone depths associated with the existence of the root, whether they be cold downwellings or elevated temperatures due to the insulating effect of the root, are thus either non-existent or below the resolution of the study.

Uranium Concentration of Contaminated Zone due to the Cover Depth for Self-Disposal

International Nuclear Information System (INIS)

Koo, Dae Seo; Sung, Hyun Hee; Kim, Gye Nam; Kim, Seung Soo; Kim, Il Gook; Han, Gyu Seong; Choi, Jong Won

2016-01-01

To acquire radiation dose under self disposal from them, the study on decontamination of some uranium contaminated soil and concrete wastes was performed using electrokinetic-electrodialytic. In this study, we evaluated radiation dose due to cover depth on contaminated zone such as uranium contaminated soil and concrete wastes under radiation dose limit using RESRAD Version 6.5. At first, the calculation of the radiation dose on the contaminated zone are carried out. The second, the uranium concentration of contaminated zone due to the cover depth are also analyzed. The uranium contaminated soil and concrete wastes under radiation dose limit by decontaminating them have application to self-disposal of contaminated zone. The area of contaminated zone is 1,500 m"2. The thickness of contaminated zone is 2 m. The length parallel to aquifer flow is 43.702m. The age of the residents on contaminated zone is 15 years old. The period of evaluation on the contaminated zone is from regulation exemption of uranium contaminated soil and concrete wastes till 1,000 years. The calculation of the radiation dose on contaminated zone are carried out. The uranium concentration of contaminated zone due to the cover depth was also analyzed. as the cover depth increases, the uranium concentration has an increasing trend. As the cover depth increases, radiation dose of a person has a decreasing trend. As the cover depth increases, the radiation dose of residents has also a decreasing trend.

Uranium Concentration of Contaminated Zone due to the Cover Depth for Self-Disposal

Energy Technology Data Exchange (ETDEWEB)

Koo, Dae Seo; Sung, Hyun Hee; Kim, Gye Nam; Kim, Seung Soo; Kim, Il Gook; Han, Gyu Seong; Choi, Jong Won [KAERI, Daejeon (Korea, Republic of)

2016-05-15

To acquire radiation dose under self disposal from them, the study on decontamination of some uranium contaminated soil and concrete wastes was performed using electrokinetic-electrodialytic. In this study, we evaluated radiation dose due to cover depth on contaminated zone such as uranium contaminated soil and concrete wastes under radiation dose limit using RESRAD Version 6.5. At first, the calculation of the radiation dose on the contaminated zone are carried out. The second, the uranium concentration of contaminated zone due to the cover depth are also analyzed. The uranium contaminated soil and concrete wastes under radiation dose limit by decontaminating them have application to self-disposal of contaminated zone. The area of contaminated zone is 1,500 m{sup 2}. The thickness of contaminated zone is 2 m. The length parallel to aquifer flow is 43.702m. The age of the residents on contaminated zone is 15 years old. The period of evaluation on the contaminated zone is from regulation exemption of uranium contaminated soil and concrete wastes till 1,000 years. The calculation of the radiation dose on contaminated zone are carried out. The uranium concentration of contaminated zone due to the cover depth was also analyzed. as the cover depth increases, the uranium concentration has an increasing trend. As the cover depth increases, radiation dose of a person has a decreasing trend. As the cover depth increases, the radiation dose of residents has also a decreasing trend.

Immediate breast reconstruction using autologous skin graft associated with breast implant.

Science.gov (United States)

Dutra, A K; Andrade, W P; Carvalho, S M T; Makdissi, F B A; Yoshimatsu, E K; Domingues, M C; Maciel, M S

2012-02-01

Immediate breast reconstruction with skin graft is still little mentioned in the literature. Follow-up studies regarding the technique aspects are particularly scarce. The objective was to detail immediate breast reconstruction using autologous skin graft. Patients (n = 49) who underwent mastectomies and autologous immediate breast reconstruction with skin graft associated with a breast implant at A. C. Camargo Hospital (São Paulo, Brazil) between January 2007 and July 2010 were included. Information on clinical data, technique details and clinical outcome were prospectively collected. Following mastectomy, the autologous full-thickness skin graft was obtained through an inframammary fold incision along the contralateral breast in most patients. The skin graft was placed on the surface of the pectoralis major muscle after adjustments to conform to the mastectomy defect. A minimum of 10-month follow-up period was established. Patients' age ranged from 35 to 55 years and all received a silicone gel textured surface implant to obtain the necessary breast mound. The mean surgical time was 45 min, and the mean amount of skin resection was 4.5 cm in the largest diameter. Follow-up ranged from 10 to 35 months (median 23). All patients had silicone-gel textured surface implants to perform the breast mound reconstruction. No complications were observed in 87.8% of reconstructions. Forty-six patients (94%) had no complaints about the donor-site aesthetics. The result was a breast mound with a central ellipse of healed skin graft. Three (6%) poor results were observed. Thirty-six patients (67%) reported the results as good or very good. Our results lead us to conclude that autologous skin graft provided a reliable option in immediate breast reconstruction to skin-sparing mastectomy defects. The technique accomplished a single-stage implant breast reconstruction when there is inadequate skin coverage. Copyright © 2011 British Association of Plastic, Reconstructive and

Foam - novel delivery technology for remediation of vadose zone environments - 59019

International Nuclear Information System (INIS)

Jansik, Danielle; Wellman, Dawn M.; Mattigod, Shas V.; Zhong, Lirong; Zhang, Fred; Foote, Martin; Wu, Yuxin; Hubbard, Susan

2012-01-01

Deep vadose zone environments can be a primary source and pathway for contaminant migration to groundwater. These environments present unique characterization and remediation challenges that necessitate scrutiny and research. The thickness, depth, and intricacies of the deep vadose zone, combined with a lack of understanding of the key subsurface processes (e.g., biogeochemical and hydrologic) affecting contaminant migration, make it difficult to create validated conceptual and predictive models of subsurface flow dynamics and contaminant behavior across multiple scales. These factors also make it difficult to design and deploy sustainable remedial approaches and monitor long-term contaminant behavior after remedial actions. Functionally, methods for addressing contamination must remove and/or reduce transport of contaminants. This problem is particularly challenging in the arid western United States where the vadose zone is hundreds of feet thick, rendering transitional excavation methods exceedingly costly and ineffective. Delivery of remedial amendments is one of the most challenging and critical aspects for all remedy-based approaches. The conventional approach for delivery is through injection of aqueous remedial solutions. However, heterogeneous deep vadose zone environments present hydrologic and geochemical challenges that limit the effectiveness. Because the flow of solution infiltration is dominantly controlled by gravity and suction, injected liquid preferentially percolates through highly permeable pathways, by-passing low-permeability zones that frequently contain the majority of contamination. Moreover, the wetting front can readily mobilize and enhance contaminant transport to the underlying aquifer prior to stabilization. Development of innovative in-situ technologies may be the only means to meet remedial action objectives and long-term stewardship goals. Surfactants can be used to lower the liquid surface tension and create stabile foams, which

The pectinate zone is stiff and the arcuate zone determines passive basilar membrane mechanics in the gerbil

Science.gov (United States)

Xia, Hongyi; Steele, Charles R.; Puria, Sunil

2018-05-01

The gerbil basilar membrane (BM) differs from other mammalian BMs in that the lower collagen-fiber layer of the pectinate zone (PZ) forms an arch, the upper fiber layer is flat, and ground substance separates the two layers. The role of this arch has been unknown, but can be elucidated by models. In the standard simple beam model (SBM), the upper and lower collagen-fiber layers of the BM are represented as a single layer in both the PZ and the arcuate zone (AZ). In our new arch-beam model (ABM), the upper fiber layer is flat, the lower layer forms an arch in the PZ, and the two layers combine to form the flat portion of the BM in the AZ. This design is incorporated into a 3D finite-element tapered-box model of the cochlea with viscous fluid. We find in the model that the PZ rotates as a rigid body, so its specific properties have little influence, while the AZ thickness and collagen volume fraction primarily determine passive BM mechanics.

Multiscale geophysical imaging of the critical zone

Science.gov (United States)

Parsekian, Andy; Singha, Kamini; Minsley, Burke J.; Holbrook, W. Steven; Slater, Lee

2015-01-01

Details of Earth's shallow subsurface—a key component of the critical zone (CZ)—are largely obscured because making direct observations with sufficient density to capture natural characteristic spatial variability in physical properties is difficult. Yet this inaccessible region of the CZ is fundamental to processes that support ecosystems, society, and the environment. Geophysical methods provide a means for remotely examining CZ form and function over length scales that span centimeters to kilometers. Here we present a review highlighting the application of geophysical methods to CZ science research questions. In particular, we consider the application of geophysical methods to map the geometry of structural features such as regolith thickness, lithological boundaries, permafrost extent, snow thickness, or shallow root zones. Combined with knowledge of structure, we discuss how geophysical observations are used to understand CZ processes. Fluxes between snow, surface water, and groundwater affect weathering, groundwater resources, and chemical and nutrient exports to rivers. The exchange of gas between soil and the atmosphere have been studied using geophysical methods in wetland areas. Indirect geophysical methods are a natural and necessary complement to direct observations obtained by drilling or field mapping. Direct measurements should be used to calibrate geophysical estimates, which can then be used to extrapolate interpretations over larger areas or to monitor changing processes over time. Advances in geophysical instrumentation and computational approaches for integrating different types of data have great potential to fill gaps in our understanding of the shallow subsurface portion of the CZ and should be integrated where possible in future CZ research.

Determination of optimum insulation thicknesses using economical analyse for exterior walls of buildings with different masses

Directory of Open Access Journals (Sweden)

Okan Kon

2017-07-01

Full Text Available In this study, five different cities were selected from the five climatic zones according to Turkish standard TS 825, and insulation thicknesses of exterior walls of sample buildings were calculated by using optimization. Vertical perforated bricks with density of 550 kg/m3 and 1000 kg/m3 were chosen within the study content. Glass wool, expanded polystyrene (XPS, extruded polystyrene (EPS were considered as insulation materials. Additionally, natural gas, coal, fuel oil and LPG were utilized as fuel for heating process while electricity was used for cooling.  Life cycle cost (LCC analysis and degree-day method were the approaches for optimum insulation thickness calculations. As a result, in case of usage vertical perforated bricks with density of 550 kg/m3 and 1000 kg/m3 resulted different values in between 0.005-0.007 m (5-7 mm in the optimum insulation thickness calculations under different insulation materials.  Minimum optimum insulation thickness was calculated in case XPS was preferred as insulation material, and the maximum one was calculated in case of using glass wool.

Structure of the Koyna-Warna Seismic Zone, Maharashtra, India: A possible model for large induced earthquakes elsewhere

Science.gov (United States)

Catchings, Rufus D.; Dixit, M.M.; Goldman, Mark R.; Kumar, S.

2015-01-01

The Koyna-Warna area of India is one of the best worldwide examples of reservoir-induced seismicity, with the distinction of having generated the largest known induced earthquake (M6.3 on 10 December 1967) and persistent moderate-magnitude (>M5) events for nearly 50 years. Yet, the fault structure and tectonic setting that has accommodated the induced seismicity is poorly known, in part because the seismic events occur beneath a thick sequence of basalt layers. On the basis of the alignment of earthquake epicenters over an ~50 year period, lateral variations in focal mechanisms, upper-crustal tomographic velocity images, geophysical data (aeromagnetic, gravity, and magnetotelluric), geomorphic data, and correlation with similar structures elsewhere, we suggest that the Koyna-Warna area lies within a right step between northwest trending, right-lateral faults. The sub-basalt basement may form a local structural depression (pull-apart basin) caused by extension within the step-over zone between the right-lateral faults. Our postulated model accounts for the observed pattern of normal faulting in a region that is dominated by north-south directed compression. The right-lateral faults extend well beyond the immediate Koyna-Warna area, possibly suggesting a more extensive zone of seismic hazards for the central India area. Induced seismic events have been observed many places worldwide, but relatively large-magnitude induced events are less common because critically stressed, preexisting structures are a necessary component. We suggest that releasing bends and fault step-overs like those we postulate for the Koyna-Warna area may serve as an ideal tectonic environment for generating moderate- to large- magnitude induced (reservoir, injection, etc.) earthquakes.

On the estimation of ice thickness from scattering observations

Science.gov (United States)

Williams, T. D.; Squire, V. A.

2010-04-01

This paper is inspired by the proposition that it may be possible to extract descriptive physical parameters - in particular the ice thickness, of a sea-ice field from ocean wave information. The motivation is that mathematical theory describing wave propagation in such media has reached a point where the inherent heterogeneity, expressed as pressure ridge keels and sails, leads, thickness variations and changes of material property and draught, can be fully assimilated exactly or through approximations whose limitations are understood. On the basis that leads have the major wave scattering effect for most sea-ice [Williams, T.D., Squire, V.A., 2004. Oblique scattering of plane flexural-gravity waves by heterogeneities in sea ice. Proc. R. Soc. Lon. Ser.-A 460 (2052), 3469-3497], a model two dimensional sea-ice sheet composed of a large number of such features, randomly dispersed, is constructed. The wide spacing approximation is used to predict how wave trains of different period will be affected, after first establishing that this produces results that are very close to the exact solution. Like Kohout and Meylan [Kohout, A.L., Meylan, M.H., 2008. An elastic plate model for wave attenuation and ice floe breaking in the marginal ice zone. J. Geophys. Res. 113, C09016, doi:10.1029/2007JC004434], we find that on average the magnitude of a wave transmitted by a field of leads decays exponentially with the number of leads. Then, by fitting a curve based on this assumption to the data, the thickness of the ice sheet is obtained. The attenuation coefficient can always be calculated numerically by ensemble averaging but in some cases more rapidly computed approximations work extremely well. Moreover, it is found that the underlying thickness can be determined to good accuracy by the method as long as Archimedean draught is correctly provided for, suggesting that waves can indeed be effective as a remote sensing agent to measure ice thickness in areas where pressure ridges

Bottom-water observations in the Vema fracture zone

Science.gov (United States)

Eittreim, Stephen L.; Biscaye, Pierre E.; Jacobs, Stanley S.

1983-03-01

The Vema fracture zone trough, at 11°N between 41° and 45°E, is open to the west at the 5000-m level but is silled at the 4650-m level on the east where it intersects the axis of the Mid-Atlantic Ridge. The trough is filled with Antarctic Bottom Water (AABW) with a potential temperature of 1.32°C and salinity of 34.82 ppt. The bottom water is thermally well mixed in a nearly homogeneous layer about 700 m thick. The great thickness of this bottom layer, as compared with the bottom-water structure of the western Atlantic basin, may result from enhanced mixing induced by topographic constriction at the west end of the fracture zone trough. A benthic thermocline, with potential temperature gradients of about 1.2 mdeg m-1, is associated with an abrupt increase in turbidity with depth at about 1200 m above bottom. A transitional layer of more moderate temperature gradients, about 0.4 mdeg m-1, lies between the benthic thermocline above and the AABW below. The AABW layer whose depth-averaged suspended paniculate concentrations range from 8 to 19 μg L-1, is consistently higher in turbidity than the overlying waters. At the eastern end of the trough, 140 m below sill depth, very low northeastward current velocities, with maximums of 3 cm s-1, were recorded for an 11-day period.

Analysis of zircaloy oxide thickness data from PWRs

International Nuclear Information System (INIS)

Sheppard, K.D.; Speyer, D.M.; Chan, Y.Y.; Frankl, I.; Strasser, A.A.

1990-02-01

Prior EPRI funded research (Project 1250-1) resulted in a set of Zircaloy waterside corrosion models. These models were based principally on KWU reactor data. The objective of this study was to evaluate the ability of the KWU corrosion models to predict available domestic USA data for all domestic PWR vendors in order to further validate the models and to provide a consistent basis to judge the corrosion data of the domestic plants. A methodology for analyzing the large amount of data was developed and implemented in a single channel model. This model includes the capability, by a method described herein, of accounting for open core related effects (crossflow) and the effect of the immediately adjacent fuel rods, guide tubes, etc., on the coolant conditions around the fuel rods that were measured for oxide thickness. Data from the Arkansas Unit number-sign 2 (ANO-2) Combustion Engineering (C-E), Oconee Units 1 and 2 built by Babcock ampersand Wilcox (B ampersand W), and the Trojan reactor built by Westinghouse (W) were used in this study. The corrosion models previously developed, and the present single channel model methodology, were able to predict the corrosion data quite well. The maximum corrosion thickness was on the order of 20 to 40 microns in all plants studied. 13 refs., 11 figs., 5 tabs

12 CFR 561.24 - Immediate family.

Science.gov (United States)

2010-01-01

... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Immediate family. 561.24 Section 561.24 Banks and Banking OFFICE OF THRIFT SUPERVISION, DEPARTMENT OF THE TREASURY DEFINITIONS FOR REGULATIONS AFFECTING ALL SAVINGS ASSOCIATIONS § 561.24 Immediate family. The term immediate family of any natural...

The interpretation of remote sensing image on the stability of fault zone at HLW repository site

International Nuclear Information System (INIS)

Liu Linqing; Yu Yunxiang

1994-01-01

It is attempted to interpret the buried fault at the preselected HLW repository site in western Gansu province with a remote sensing image. The authors discuss the features of neotectonism of Shule River buried fault zone and its two sides in light of the remote sensing image, geomorphology, stream pattern, type and thickness difference of Quaternary sediments, and structural basin, etc.. The stability of Shule River fault zone is mainly dominated by the neotectonic movement pattern and strength of its two sides. Although there exist normal and differential vertical movements along it, their strengths are small. Therefore, this is a weakly-active passive fault zone. The east Beishan area north to Shule River fault zone is weakliest active and is considered as the target for further pre-selection for HLW repository site

Choroidal thickness in Malaysian eyes with full-thickness macular holes

Directory of Open Access Journals (Sweden)

Chew Y Tan

2018-02-01

Full Text Available AIM: To compare choroidal thickness at the macula in eyes with unilateral idiopathic full-thickness macular holes(FTMHwith that of unaffected fellow eyes, and eyes of normal control patients.METHODS: Cross-sectional study. Thirty patients with unilateral idiopathic FTMH and thirty age, sex, and race-matched controls were recruited. Axial lengths were measured using laser interferometry. Enhanced depth imaging optical coherence tomography images were obtained using Heidelberg spectral-domain optical coherence tomography. Choroidal thickness was measured at the fovea, and at 1 mm and 2 mm nasally, temporally, superiorly and inferiorly from the center of the fovea. Statistical analysis was performed using independent and paired t-tests, chi-square tests, and Pearson correlation tests(PRESULTS: The mean subfoveal choroidal thickness was 201.0±44.0 μm in the FTMH group, 225.3±51.4 μm in the fellow eye group and 262.3±70.3 μm in the control group. The choroid was thinner in FTMH eyes at all locations when compared to control eyes(PPP>0.05. Choroidal thickness was generally highest subfoveally and lowest nasally. Subfoveal choroidal thickness was negatively correlated with age(r=-0.278, P=0.032, and axial length(r=-0.328, P=0.011.CONCLUSION: Choroidal thickness is lower in both eyes of patients with unilateral FTMH compared to healthy control eyes.

Structure of the heat-affected zone in the 24 Kh2NMFA steel welded joints

International Nuclear Information System (INIS)

German, S.I.; Levenberg, N.E.; Netesa, E.M.; Fomina, O.P.

1977-01-01

It is shown that in the heat-affected zone of the joints welded with preheating there appears a bainite having a complex composition and the following structure: asub(m)+(M+Asub(ret)). The matrix of the bainite is represented by an a-solid solution formed by martensite kinetics (asub(m)). Small regions of granular or elongated shape, uniformly distributed over the bainite matrix, are either a retained austenite (Asub(ret)) or a martensite with a retained austenite (M+Asub(ret)). The non-equilibrium character of the bainite phases is, to a large extent, responsible for the inadmissably high hardness of the heat-affected zone immediately after welding

Bayesian inference for heterogeneous caprock permeability based on above zone pressure monitoring

Energy Technology Data Exchange (ETDEWEB)

Namhata, Argha; Small, Mitchell J.; Dilmore, Robert M.; Nakles, David V.; King, Seth

2017-02-01

The presence of faults/ fractures or highly permeable zones in the primary sealing caprock of a CO2 storage reservoir can result in leakage of CO2. Monitoring of leakage requires the capability to detect and resolve the onset, location, and volume of leakage in a systematic and timely manner. Pressure-based monitoring possesses such capabilities. This study demonstrates a basis for monitoring network design based on the characterization of CO2 leakage scenarios through an assessment of the integrity and permeability of the caprock inferred from above zone pressure measurements. Four representative heterogeneous fractured seal types are characterized to demonstrate seal permeability ranging from highly permeable to impermeable. Based on Bayesian classification theory, the probability of each fractured caprock scenario given above zone pressure measurements with measurement error is inferred. The sensitivity to injection rate and caprock thickness is also evaluated and the probability of proper classification is calculated. The time required to distinguish between above zone pressure outcomes and the associated leakage scenarios is also computed.

Evidence for strong Holocene earthquake(s) in the Wabash Valley seismic zone

International Nuclear Information System (INIS)

Obermeier, S.

1991-01-01

Many small and slightly damaging earthquakes have taken place in the region of the lower Wabash River Valley of Indiana and Illinois during the 200 years of historic record. Seismologists have long suspected the Wabash Valley seismic zone to be capable of producing earthquakes much stronger than the largest of record (m b 5.8). The seismic zone contains the poorly defined Wabash Valley fault zone and also appears to contain other vaguely defined faults at depths from which the strongest earthquakes presently originate. Faults near the surface are generally covered with thick alluvium in lowlands and a veneer of loess in uplands, which make direct observations of faults difficult. Partly because of this difficulty, a search for paleoliquefaction features was begun in 1990. Conclusions of the study are as follows: (1) an earthquake much stronger than any historic earthquake struck the lower Wabash Valley between 1,500 and 7,500 years ago; (2) the epicentral region of the prehistoric strong earthquake was the Wabash Valley seismic zone; (3) apparent sites have been located where 1811-12 earthquake accelerations can be bracketed

The quantitative measurements of foveal avascular zone using optical coherence tomography angiography in normal volunteers.

Science.gov (United States)

Ghassemi, Fariba; Mirshahi, Reza; Bazvand, Fatemeh; Fadakar, Kaveh; Faghihi, Houshang; Sabour, Siamak

2017-12-01

To provide normative data of foveal avascular zone (FAZ) and thickness. In this cross-sectional study both eyes of each normal subject were scanned with optical coherence tomography angiography (OCTA) for foveal superficial and deep avascular zone (FAZ) and central foveal thickness (CFT) and parafoveal thickness (PFT). Out of a total of 224 eyes of 112 volunteers with a mean age of 37.03 (12-67) years, the mean superficial FAZ area was 0.27 mm 2 , and deep FAZ area was 0.35 mm 2 ( P  < 0.001), with no difference between both eyes. Females had a larger superficial (0.32 ± 0.11 mm 2 versus 0.23 ± 0.09 mm 2 ) and deep FAZ (0.40 ± 0.14 mm 2 versus 0.31 ± 0.10 mm 2 ) ( P  < 0.001) than males. By multivariate linear regression analysis, in normal eyes, superficial FAZ area varied significantly with the gender, CFT, and deep FAZ. Deep FAZ varied with the gender and CFT. The gender and CFT influence the size of normal superficial and deep FAZ of capillary network.

Analysis of the Corrosion Behavior of an A-TIG Welded SS 409 Weld Fusion Zone

Science.gov (United States)

Vidyarthy, R. S.; Dwivedi, D. K.

2017-11-01

AISI 409 (SS 409) ferritic stainless steel is generally used as the thick gauge section in freight train wagons, in ocean containers, and in sugar refinery equipment. Activating the flux tungsten inert gas (A-TIG) welding process can reduce the welding cost during fabrication of thick sections. However, corrosion behavior of the A-TIG weld fusion zone is a prime concern for this type of steel. In the present work, the effect of the A-TIG welding process parameters on the corrosion behavior of a weld fusion zone made of 8-mm-thick AISI 409 ferritic stainless-steel plate has been analyzed. Potentiodynamic polarization tests were performed to evaluate the corrosion behavior. The maximum corrosion potential ( E corr) was shown by the weld made using a welding current of 215 A, a welding speed of 95 mm/min, and a flux coating density of 0.81 mg/cm2. The minimum E corr was observed in the weld made using a welding current of 190 A, a welding speed of 120 mm/min, and a flux coating density of 1.40 mg/cm2. The current study also presents the inclusive microstructure-corrosion property relationships using the collective techniques of scanning electron microscopy, energy-dispersive x-ray spectroscopy, and x-ray diffraction.

The Effect of Hierarchical Micro/Nanotextured Titanium Implants on Osseointegration Immediately After Tooth Extraction in Beagle Dogs.

Science.gov (United States)

Fu, Qian; Bellare, Anuj; Cui, Yajun; Cheng, Bingkun; Xu, Shanshan; Kong, Liang

2017-06-01

Owing to simplify the operation and shorten the overall duration of treatment, immediate implantation earned much satisfactory from patients and dentists. The results of immediate implantation determined by osseointegration, we fabricated a micro/nanotextured titanium implants to improve osseointegration immediately after tooth extraction. The aim of this study was to investigate the effect of hierarchical micro/nanotextured titanium implant on osseointegration immediately after tooth extraction. The micro/nanotextured titanium implants were fabricated by etching with 0.5 wt% hydrofluoric (HF) acid followed by anodization in HF electrolytes. Implants with a machined surface as well as implants a microtextured surface prepared by 0.5 wt% HF etching served as control groups. The machined, microtextured, and micro/nanotextured implants were inserted into fresh sockets immediately after tooth extraction in beagle dogs. Twelve weeks after implantation, the animals were sacrificed for micro-CT scanning, histological analysis and biomechanical test. The micro-CT imaging revealed that the bone volume/total volume (BV/TV) and trabecular thickness (Tb.Th) in the micro/nanotextured group was significantly higher than that in the machined group and microtextured group, and the trabecular separation (Tb.Sp) in the micro/nanotextured group was significantly lower than that in the other groups. For the histological analysis, the bone-to-implant contact in the machined, micro and micro/nanotextured groups were 47.13 ± 6.2%, 54.29 ± 4.18%, and 63.38 ± 7.63%, respectively, and the differences significant. The maximum pull-out force in the machined, micro, and micro/nanotextured groups were 216.58 ± 38.71 N, 259.42 ± 28.93 N, and 284.73 ± 47.09 N, respectively. The results indicated that implants with a hierarchical micro/nanotextured can promote osseointegration immediately after tooth extraction. © 2016 Wiley Periodicals, Inc.

Seismotectonics and Crustal Thickness of Northwest Mindoro, Philippines

Science.gov (United States)

Chen, P. F.; Olavere, E. A.; Lee, K. M.; Bautista, B.; Solidum, R., Jr.; Huang, B. S.

2015-12-01

Mindoro Island locates where the Palawan Continental Block (PCB) indented into the Philippine Mobile Belt (PMB) during the Early Miocene and where the Manila Trench terminates, having ceased convergence due to collision. On the transition from subduction to collision, Northwest Mindoro exhibits vigorous seismic activity and has been debated about its affiliation being PCB or PMB. Here, we use data from both the EHB and Global Centroid Moment Tensor catalogues to study the regional seismotectonics. We also deployed five broadband stations to probe the crustal thickness beneath NW Mindoro using receiver function analysis. Results show that, following the southeasterly reduction of convergence rates at the southern termination of the Manila Trench, the slab dipping angles steepen, were initiated at depth (~200 km) and propagate upwards. The horizontal distances of the trench and slab, as measured from the Wadati-Benioff zone at 200 km depth, also reduce in a southeasterly direction. Observations of intermediate-depth earthquakes that exhibit predominantly down-dip extensional stress patterns attest that the steepening of slab dipping angles is due to the negative buoyancy of the slab. Preliminary results of receiver function analysis suggest that the crustal thickness beneath NW Mindoro is about 40 km and is probably PCB affiliated.

Laser surface pretreatment of 100Cr6 bearing steel – Hardening effects and white etching zones

International Nuclear Information System (INIS)

Buling, Anna; Sändker, Hendrik; Stollenwerk, Jochen; Krupp, Ulrich; Hamann-Steinmeier, Angela

2016-01-01

Highlights: • Laser surface pretreatment of the bearing steel 100Cr6 is performed. • Microstructural changes of the surface are examined by light microscopy and SEM. • Topographical changes are observed using white light interferometry. • Micro-hardness testing show the existence of very hard white etching zones (WEZ). • WEZ are attributed to near-surface reaustenitization and rapid quenching. • Dark etching zones (DEZ) are found at the laser path edges after laser pretreatment. - Abstract: In order to achieve a surface pretreatment of the bearing steel 100Cr6 (1–1.5 wt.% Cr) a laser-based process was used. The obtained modification may result in an optimization of the adhesive properties of the surface with respect to an anticorrosion polymer coating on the basis of PEEK (poly-ether-ether-ketone), which is applied on the steel surface by a laser melting technique. This work deals with the influence of the laser-based pretreatment regarding the surface microstructure and the micro-hardness of the steel, which has been examined by scanning electron microscopy (SEM), light microscopy and automated micro-hardness testing. The most suitable parameter set for the laser-based pretreatment leads to the formation of very hard white etching zones (WEZ) with a thickness of 23 μm, whereas this pretreatment also induces topographical changes. The occurrence of the white etching zones is attributed to near-surface re-austenitization and rapid quenching. Moreover, dark etching zones (DEZ) with a thickness of 32 μm are found at the laser path edges as well as underneath the white etching zones (WEZ). In these areas, the hardness is decreased due to the formation of oxides as a consequence of re-tempering.

Laser surface pretreatment of 100Cr6 bearing steel – Hardening effects and white etching zones

Energy Technology Data Exchange (ETDEWEB)

Buling, Anna, E-mail: a.buling@hs-osnabrueck.de [Faculty of Engineering and Computer Science, University of Applied Sciences, 49009 Osnabrück (Germany); Sändker, Hendrik; Stollenwerk, Jochen [Fraunhofer Institute for Laser Technology ILT, Steinbachstrasse 15, 52074 Aachen (Germany); Krupp, Ulrich; Hamann-Steinmeier, Angela [Faculty of Engineering and Computer Science, University of Applied Sciences, 49009 Osnabrück (Germany)

2016-08-15

Highlights: • Laser surface pretreatment of the bearing steel 100Cr6 is performed. • Microstructural changes of the surface are examined by light microscopy and SEM. • Topographical changes are observed using white light interferometry. • Micro-hardness testing show the existence of very hard white etching zones (WEZ). • WEZ are attributed to near-surface reaustenitization and rapid quenching. • Dark etching zones (DEZ) are found at the laser path edges after laser pretreatment. - Abstract: In order to achieve a surface pretreatment of the bearing steel 100Cr6 (1–1.5 wt.% Cr) a laser-based process was used. The obtained modification may result in an optimization of the adhesive properties of the surface with respect to an anticorrosion polymer coating on the basis of PEEK (poly-ether-ether-ketone), which is applied on the steel surface by a laser melting technique. This work deals with the influence of the laser-based pretreatment regarding the surface microstructure and the micro-hardness of the steel, which has been examined by scanning electron microscopy (SEM), light microscopy and automated micro-hardness testing. The most suitable parameter set for the laser-based pretreatment leads to the formation of very hard white etching zones (WEZ) with a thickness of 23 μm, whereas this pretreatment also induces topographical changes. The occurrence of the white etching zones is attributed to near-surface re-austenitization and rapid quenching. Moreover, dark etching zones (DEZ) with a thickness of 32 μm are found at the laser path edges as well as underneath the white etching zones (WEZ). In these areas, the hardness is decreased due to the formation of oxides as a consequence of re-tempering.

Summary of Vadose -- Zone Conceptual Models for Flow and Contaminant Transport and 1999 - 2003 Progress on Resolving Deficiencies in Understanding the Vadose Zone at the INEEL

Energy Technology Data Exchange (ETDEWEB)

Robert C. Starr; Dana L. Dettmers; Brennon R. Orr; Thomas R. Wood

2003-12-01

The thick vadose zone that underlies the Idaho National Engineering and Environmental Laboratory has been recognized both as an avenue through which contaminants disposed at or near the ground surface can migrate to groundwater in the underlying Eastern Snake River Plain aquifer, and as a barrier to the movement of contaminants into the aquifer. Flow and contaminant transport in the vadose zone at the INEEL is complicated by the highly heterogeneous nature of the geologic framework and by the variations in the behavior of different contaminants in the subsurface. The state of knowledge concerning flow and contaminant transport in the vadose zone at and near the INEEL IN 1999 was summarized in Deficiencies in Vadose Zone Understanding at the Idaho National Engineering and Environmental Laboratory (Wood et al., 2000). These authors identified deficiencies in knowledge of flow and contaminant transport processes in the vadose zone, and provided recommendations for additional work that should be conducted to address these deficiencies. In the period since (Wood et al., 2000) was prepared, research has been published that, to some degree, address these deficiencies. This document provides a bibliography of reports, journal articles, and conference proceedings published 1999 through mid-2003 that are relevant to the vadose zone at or near the INEEL and provides a brief description of each work. Publications that address specific deficiencies or recommendations are identified, and pertinent information from selected publications is presented.

FLUID EVOLUTION AND MINERAL REACTIONS DURING SHEAR ZONE FORMATION AT NUSFJORD, LOFOTEN, NORWAY (Invited)

Science.gov (United States)

Kullerud, K.

2009-12-01

At Nusfjord in Lofoten, Norway, three 0.3 - 3 m thick shear zones occur in a gabbro-anorthosite. During deformation, the shear zones were infiltrated by a hydrous fluid enriched in Cl. In the central parts of the shear zones, fluid-rock interaction resulted in complete break-down of the primary mafic silicates. Complete hydration of these minerals to Cl-free amphibole and biotite suggests that the hydrous fluid was present in excess during deformation in these parts of the shear zones. Along the margins of the shear zones, however, the igneous mafic silicates (Cpx, Bt, Opx) were only partly overgrown by hydrous minerals. Here, Cl-enriched minerals (Amph, Bt, Scp, Ap) can be observed. Amphibole shows compositions covering the range 0.1 - 4.0 wt % Cl within single thin sections. Mineral textures and extreme compositional variations of the Cl-bearing minerals indicate large chemical gradients of the fluid phase. Relics of primary mafic silicates and compositionally zoned reaction coronas around primary mafic silicates suggest that the free fluid was totally consumed before the alteration of the primary phases were completed. The extreme variations in the Cl-content of amphibole are inferred to monitor a gradual desiccation of the Cl-bearing grain-boundary fluid during fluid-mineral reactions accordingly: 1) The first amphibole that formed during the reactions principally extracted water from the fluid, resulting in a slight increase in the Cl content of the fluid. 2) Continued amphibole-forming reactions resulted in gradual consumption of the free fluid phase, principally by extracting water from the fluid, resulting in an increase in its Cl-content. Higher Cl-content of the fluid resulted in higher Cl-content of the equilibrium amphibole. 3) The most Cl-enriched amphibole (4 wt % Cl) formed in equilibrium with the last volumes of the grain-boundary fluid, which had evolved to a highly saline solution. Mineral reactions within a 1-2 thick zone of the host rock along

Toward an Integrated Model for the Composition, Structure, and Physical Properties of the Crust in Icelandic Rift Zones

Science.gov (United States)

Kelley, D. F.; Panero, W. R.; Barton, M.

2009-05-01

The rift zones that extend across Iceland roughly southwest to northeast are the only portion of the mid-Atlantic Ridge that is exposed above sea level. This reflects anomalously high melt productivity in the mantle leading to anomalously thick oceanic crust. There are 30 active volcanic centers in the rift zones. Petrologic studies of the 30 volcanic centers in the active rift zones show that, magmas pond at a mid-crustal level as well as at the base of the crust prior to eruption. The depth of magma chambers at the base of the crust provides an estimate of crustal thickness of (20 ± 2.5 km) in these zones. Melts erupting to the surface directly from chambers at the base of the crust provide one constraint on the composition of the crust because any compositional variations within the crust must be the result of differentiation of these melts. However, the glass compositions indicate that relatively evolved magmas erupted from the deep chambers, suggesting that crystallization of compositionally more primitive magmas also occurred at the base of the crust. Knowledge of crustal thickness, the temperature of melts at the base of the crust, and the compositions of these melts allows development of comprehensive models of the composition, structure and properties of crust within the rift zones. We have developed two end member models: one with variation of mineralogy with depth in the crust due to metamorphism, and one with variation of crustal composition with depth due to fractionation processes. We have also considered models that are plausible combinations of these two end member models. We have calculated well constrained geothermal gradients and used these to predict variations in density, seismic velocity, and bulk modulus with depth. These models which include petrologic and geochemical data are consistent with published geophysical data, therefore provide important constraints on interpretation of geophysical data. In particular, results of this work provide

A Cryptic Sulfur Cycle in Oxygen-Minimum-Zone Waters off the Chilean Coast

OpenAIRE

Canfield, D. E.; Thamdrup, B.; De Brabandere, L.; Dalsgaard, T.; Revsbech, N. P.; Ulloa, O.; Stewart, Frank J.; DeLong, Edward Francis

2010-01-01

Nitrogen cycling is normally thought to dominate the biogeochemistry and microbial ecology of oxygen-minimum zones in marine environments. Through a combination of molecular techniques and process rate measurements, we showed that both sulfate reduction and sulfide oxidation contribute to energy flux and elemental cycling in oxygen-free waters off the coast of northern Chile. These processes may have been overlooked because in nature, the sulfide produced by sulfate reduction immediately oxid...

Corrosion Behavior of Low-C Medium-Mn Steel in Simulated Marine Immersion and Splash Zone Environment

Science.gov (United States)

Zhang, Dazheng; Gao, Xiuhua; Su, Guanqiao; Du, Linxiu; Liu, Zhenguang; Hu, Jun

2017-05-01

The corrosion behavior of low-C medium-Mn steel in simulated marine immersion and splash zone environment was studied by static immersion corrosion experiment and wet-dry cyclic corrosion experiment, respectively. Corrosion rate, corrosion products, surface morphology, cross-sectional morphology, elemental distribution, potentiodynamic polarization curves and electrochemical impedance spectra were used to elucidate the corrosion behavior of low-C medium-Mn steel. The results show that corrosion rate in immersion zone is much less than that in splash zone owing to its relatively mild environment. Manganese compounds are detected in the corrosion products and only appeared in splash zone environment, which can deteriorate the protective effect of rust layer. With the extension of exposure time, corrosion products are gradually transformed into dense and thick corrosion rust from the loose and porous one in these two environments. But in splash zone environment, alloying elements of Mn appear significant enrichment in the rust layer, which decrease the corrosion resistance of the steel.

Use of autologous tissue engineered skin to treat porcine full-thickness skin defects

Institute of Scientific and Technical Information of China (English)

CAI Xia; CAO Yi-lin; CUI Lei; LIU Wei; GUAN Wen-xiang

2005-01-01

Objective: To explore a feasible method to repair full-thickness skin defects utilizing tissue engineered techniques. Methods: The Changfeng hybrid swines were used and the skin specimens were cut from the posterior limb girdle region, from which the keratinocytes and fibroblasts were isolated and harvested by trypsin, EDTA, and type II collagenase. The cells were seeded in Petri dishes for primary culture. When the cells were in logarithmic growth phase, they were treated with trypsin to separate them from the floor of the tissue culture dishes. A biodegradable material, Pluronic F-127, was prefabricated and mixed with these cells, and then the cell-Pluronic compounds were seeded evenly into a polyglycolic acid (PGA). Then the constructs were replanted to the autologous animals to repair the full-thickness skin defects. Histology and immunohistochemistry of the neotissue were observed in 1, 2, 4, and 8 postoperative weeks. Results: The cell-Pluronic F-127-PGA compounds repaired autologous full-thickness skin defects 1 week after implantation. Histologically, the tissue engineered skin was similar to the normal skin with stratified epidermis overlying a moderately thick collageneous dermis. Three of the structural proteins in the epidermal basement membrane zone, type IV collagen, laminin, and type VII collagen were detected using immunohistochemical methods. Conclusions: By studying the histology and immunohistochemistry of the neotissue, the bioengineered skin graft holds great promise for improving healing of the skin defects.

Critical zone architecture and processes: a geophysical perspective

Science.gov (United States)

Holbrook, W. S.

2016-12-01

The "critical zone (CZ)," Earth's near-surface layer that reaches from treetop to bedrock, sustains terrestrial life by storing water and producing nutrients. Despite is central importance, however, the CZ remains poorly understood, due in part to the complexity of interacting biogeochemical and physical processes that take place there, and in part due to the difficulty of measuring CZ properties and processes at depth. Major outstanding questions include: What is the architecture of the CZ? How does that architecture vary across scales and across gradients in climate, lithology, topography, biology and regional states of stress? What processes control the architecture of the CZ? At what depth does weathering initiate, and what controls the rates at which it proceeds? Based on recent geophysical campaigns at seven Critical Zone Observatory (CZO) sites and several other locations, a geophysical perspective on CZ architecture and processes is emerging. CZ architecture can be usefully divided into four layers, each of which has distinct geophysical properties: soil, saprolite, weathered bedrock and protolith. The distribution of those layers across landscapes varies depending on protolith composition and internal structure, topography, climate (P/T) and the regional state of stress. Combined observations from deep CZ drilling, geophysics and geochemistry demonstrate that chemical weathering initiates deep in the CZ, in concert with mechanical weathering (fracturing), as chemical weathering appears concentrated along fractures in borehole walls. At the Calhoun CZO, the plagioclase weathering front occurs at nearly 40 m depth, at the base of a 25-m-thick layer of weathered bedrock. The principal boundary in porosity, however, occurs at the saprolite/weathered bedrock boundary: porosity decreases over an order of magnitude, from 50% to 5% over an 8-m-thick zone at the base of saprolite. Porosity in weathered bedrock is between 2-5%. Future progress will depend on (1

Thick SS316 materials TIG welding development activities towards advanced fusion reactor vacuum vessel applications

Science.gov (United States)

Kumar, B. Ramesh; Gangradey, R.

2012-11-01

Advanced fusion reactors like ITER and up coming Indian DEMO devices are having challenges in terms of their materials design and fabrication procedures. The operation of these devices is having various loads like structural, thermo-mechanical and neutron irradiation effects on major systems like vacuum vessel, divertor, magnets and blanket modules. The concept of double wall vacuum vessel (VV) is proposed in view of protecting of major reactor subsystems like super conducting magnets, diagnostic systems and other critical components from high energy 14 MeV neutrons generated from fusion plasma produced by D-T reactions. The double walled vacuum vessel is used in combination with pressurized water circulation and some special grade borated steel blocks to shield these high energy neutrons effectively. The fabrication of sub components in VV are mainly used with high thickness SS materials in range of 20 mm- 60 mm of various grades based on the required protocols. The structural components of double wall vacuum vessel uses various parts like shields, ribs, shells and diagnostic vacuum ports. These components are to be developed with various welding techniques like TIG welding, Narrow gap TIG welding, Laser welding, Hybrid TIG laser welding, Electron beam welding based on requirement. In the present paper the samples of 20 mm and 40 mm thick SS 316 materials are developed with TIG welding process and their mechanical properties characterization with Tensile, Bend tests and Impact tests are carried out. In addition Vickers hardness tests and microstructural properties of Base metal, Heat Affected Zone (HAZ) and Weld Zone are done. TIG welding application with high thick SS materials in connection with vacuum vessel requirements and involved criticalities towards welding process are highlighted.

Thick SS316 materials TIG welding development activities towards advanced fusion reactor vacuum vessel applications

International Nuclear Information System (INIS)

Kumar, B Ramesh; Gangradey, R

2012-01-01

Advanced fusion reactors like ITER and up coming Indian DEMO devices are having challenges in terms of their materials design and fabrication procedures. The operation of these devices is having various loads like structural, thermo-mechanical and neutron irradiation effects on major systems like vacuum vessel, divertor, magnets and blanket modules. The concept of double wall vacuum vessel (VV) is proposed in view of protecting of major reactor subsystems like super conducting magnets, diagnostic systems and other critical components from high energy 14 MeV neutrons generated from fusion plasma produced by D-T reactions. The double walled vacuum vessel is used in combination with pressurized water circulation and some special grade borated steel blocks to shield these high energy neutrons effectively. The fabrication of sub components in VV are mainly used with high thickness SS materials in range of 20 mm- 60 mm of various grades based on the required protocols. The structural components of double wall vacuum vessel uses various parts like shields, ribs, shells and diagnostic vacuum ports. These components are to be developed with various welding techniques like TIG welding, Narrow gap TIG welding, Laser welding, Hybrid TIG laser welding, Electron beam welding based on requirement. In the present paper the samples of 20 mm and 40 mm thick SS 316 materials are developed with TIG welding process and their mechanical properties characterization with Tensile, Bend tests and Impact tests are carried out. In addition Vickers hardness tests and microstructural properties of Base metal, Heat Affected Zone (HAZ) and Weld Zone are done. TIG welding application with high thick SS materials in connection with vacuum vessel requirements and involved criticalities towards welding process are highlighted.

Progression and timing of treatment of zone I retinopathy of prematurity.

Science.gov (United States)

Soh, Yuka; Fujino, Takahiro; Hatsukawa, Yoshikazu

2008-09-01

To clarify the progression of zone I retinopathy of prematurity (ROP) and elucidate the most suitable time and method of treatment. Interventional case series. Forty-six eyes of 23 zone I ROP infants were studied at a single institution. Birth weight ranged from 448 to 954 g, and gestational age ranged from 22 to 26 weeks. Fundus examination was started at 29 or 30 weeks postmenstrual age and was performed once or more per week. The first treatment was performed using laser photocoagulation or cryotherapy when zone I ROP progressed to the following criteria. Treatment criteria A included 35 eyes of 18 cases of zone I any stage ROP with plus disease (Early Treatment for Retinopathy of Prematurity [ETROP] type 1), criteria B included five eyes of three cases of zone I stage 3 ROP with or without plus disease (ETROP type 1), criteria C included six eyes of four cases of stage 1 or stage 2 ROP without plus disease; the demarcation lines belonged, in large part, within the zone I area. Hazy media such as corneal opacity, miotic pupil, tunica vasculosa lentis, and hazy vitreous persisted until approximately 32 weeks postmenstrual age. The mean period between stage 1 and stage 3 mild was one week, that between stage 1 and stage 3 moderate was 1.7 weeks, and that between stage 1 and stage 3 severe was 1.3 weeks. The period between stage 1 and the first treatment was zero to 20 days, and 60.9% of all the cases were treated within 10 days after stage 1. Six of 46 eyes had unfavorable outcomes. Surgical results of our treatment were comparable or better than those of other reports. Immediate treatment was required when zone I ROP was diagnosed behind persistent hazy media.

The effect of adipose derived stromal vascular fraction on stasis zone in an experimental burn model.

Science.gov (United States)

Eyuboglu, Atilla Adnan; Uysal, Cagri A; Ozgun, Gonca; Coskun, Erhan; Markal Ertas, Nilgun; Haberal, Mehmet

2018-03-01

Stasis zone is the surrounding area of the coagulation zone which is an important part determining the extent of the necrosis in burn patients. In our study we aim to salvage the stasis zone by injecting adipose derived stromal vascular fraction (ADSVF). Thermal injury was applied on dorsum of Sprague-Dawley rats (n=20) by the "comb burn" model as described previously. When the burn injury was established on Sprague-Dawley rats (30min); rat dorsum was separated into 2 equal parts consisting of 4 burn zones (3 stasis zone) on each pair. ADSVF cells harvested from inguinal fat pads of Sprague-Dawley rats (n=5) were injected on the right side while same amount of phosphate buffered saline (PBS) injected on the left side of the same animal. One week later, average vital tissue on the statis zone was determined by macroscopy, angiography and microscopy. Vascular density, inflammatory cell density, gradient of fibrosis and epithelial thickness were determined via immunohistochemical assay. Macroscopic stasis zone tissue viability (32±3.28%, 57±4.28%) (p51, 1.50±0.43) (pzone on acute burn injuries. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

Estimating the time and temperature relationship for causation of deep-partial thickness skin burns.

Science.gov (United States)

Abraham, John P; Plourde, Brian; Vallez, Lauren; Stark, John; Diller, Kenneth R

2015-12-01

The objective of this study is to develop and present a simple procedure for evaluating the temperature and exposure-time conditions that lead to causation of a deep-partial thickness burn and the effect that the immediate post-burn thermal environment can have on the process. A computational model has been designed and applied to predict the time required for skin burns to reach a deep-partial thickness level of injury. The model includes multiple tissue layers including the epidermis, dermis, hypodermis, and subcutaneous tissue. Simulated exposure temperatures ranged from 62.8 to 87.8°C (145-190°F). Two scenarios were investigated. The first and worst case scenario was a direct exposure to water (characterized by a large convection coefficient) with the clothing left on the skin following the exposure. A second case consisted of a scald insult followed immediately by the skin being washed with cool water (20°C). For both cases, an Arrhenius injury model was applied whereby the extent and depth of injury were calculated and compared for the different post-burn treatments. In addition, injury values were compared with experiment data from the literature to assess verification of the numerical methodology. It was found that the clinical observations of injury extent agreed with the calculated values. Furthermore, inundation with cool water decreased skin temperatures more quickly than the clothing insulating case and led to a modest decrease in the burn extent. Copyright © 2015 Elsevier Ltd and ISBI. All rights reserved.

Calculation of Radioactivity Concentration on Cover Depth of Contaminated Zone for Self-Disposal

Energy Technology Data Exchange (ETDEWEB)

Koo, Daeseo; Sung, Hyun-Hee; Kim, Gye-Nam; Kim, Seung-Soo; Kim, Ilgook; Han, Gyu Seong; Choi, Jong-Won [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2015-10-15

We have a lot of uranium contaminated soil and concrete wastes owing to dismantlement of uranium conversion facility. There are several radioactive material disposal methods such as regulation exemption, decontamination and long term storage. It is necessary for us to perform permanent disposal of these wastes. To acquire radiation dose under self-disposal from them, the study on decontamination of some uranium contaminated soil and concrete wastes was performed using electrokinectic-electrodialytic. In this study, we evaluated radiation dose on the cover depth of contaminated zone from the wastes under radiation dose limit using RESRAD Version 6.5. At first, the calculation of the radiation dose on the wastes of contaminated zone are carried out. The second, the cover depth of contaminated zone are analyzed. The application to self-disposal of contaminated zone are also analyzed. To acquire radiation dose under self-disposal from uranium contaminated soil and concrete wastes, we decontaminated some uranium contaminated soil and concrete wastes using electrokinectic-electrodialytic. To perform self-disposal of the quantity (30,000kg) of contaminated zone, the calculating conditions for radiation dose on the cover depth of contaminated zone are as follows. The area of contaminated zone is 10m{sup 2}. The thickness of contaminated zone is 2 m. The cover depth of contaminated zone are analyzed. The application to self-disposal of contaminated zone are also analyzed. Therefore, as the cover depth increases, the uranium concentration has an increasing trend. It realize that the cover depth of contaminated zone is adequate < 2m at the quantity(30,000kg) of contaminated zone. As the cover depth increases, the uranium concentration has a decreasing trend. As the cover depth increases, the radiation dose(residents) has also a decreasing trend.

Study of the water content and relaxation properties of the uterine junctional zone

International Nuclear Information System (INIS)

McCarthy, S.; Scott, G.; Majumdar, S.; Thompson, S.; Shapiro, B.; Lange, R.; Gore, J.

1988-01-01

Nine hysterectomy specimens were imaged at 1.5T (General Electric Sigma), 5-mm single section, repetition time msec/echo time msec = 2,000/ 20, 40, 60, 80; and 500/20. With the use of tissue thickness measured from the images, weighed samples of myometrium, junctional zone, and endometrium were excised for determination of T1 and T2 in a 20-MHz spectrometer and then dried for determination of water content. The remainder of the uterus, examined with special histopathologic stains, demonstrated no significant difference in the number of blood vessels, smooth muscle cells, fibroblasts, elastin, iron, collagen, mucin, polysaccharide, or amyloid. The junctional zone water content (79.28%) was significantly lower than those of endometrium (82.88%; P = .004) and myometrium (8.05%; P = .0046). The T1 of the junctional zone (643) was significantly lower than those of endometrium (836, P = .004) and myometrium (709; P = .0114). Junctional zone T2 (58) was significantly lower than those of endometrium (87; P = .0114) and myometrium (66.7; P = .006)

Numerical Simulation Study on Steam-Assisted Gravity Drainage Performance in a Heavy Oil Reservoir with a Bottom Water Zone

Directory of Open Access Journals (Sweden)

Jun Ni

2017-12-01

Full Text Available In the Pikes Peak oil field near Lloydminster, Canada, a significant amount of heavy oil reserves is located in reservoirs with a bottom water zone. The properties of the bottom water zone and the operation parameters significantly affect oil production performance via the steam-assisted gravity drainage (SAGD process. Thus, in order to develop this type of heavy oil resource, a full understanding of the effects of these properties is necessary. In this study, the numerical simulation approach was applied to study the effects of properties in the bottom water zone in the SAGD process, such as the initial gas oil ratio, the thickness of the reservoir, and oil saturation of the bottom water zone. In addition, some operation parameters were studied including the injection pressure, the SAGD well pair location, and five different well patterns: (1 two corner wells, (2 triple wells, (3 downhole water sink well, (4 vertical injectors with a horizontal producer, and (5 fishbone well. The numerical simulation results suggest that the properties of the bottom water zone affect production performance extremely. First, both positive and negative effects were observed when solution gas exists in the heavy oil. Second, a logarithmical relationship was investigated between the bottom water production ratio and the thickness of the bottom water zone. Third, a non-linear relation was obtained between the oil recovery factor and oil saturation in the bottom water zone, and a peak oil recovery was achieved at the oil saturation rate of 30% in the bottom water zone. Furthermore, the operation parameters affected the heavy oil production performance. Comparison of the well patterns showed that the two corner wells and the triple wells patterns obtained the highest oil recovery factors of 74.71% and 77.19%, respectively, which are almost twice the oil recovery factors gained in the conventional SAGD process (47.84%. This indicates that the optimized SAGD process

S-velocity structure in Cimandiri fault zone derived from neighbourhood inversion of teleseismic receiver functions

Science.gov (United States)

Syuhada; Anggono, T.; Febriani, F.; Ramdhan, M.

2018-03-01

The availability information about realistic velocity earth model in the fault zone is crucial in order to quantify seismic hazard analysis, such as ground motion modelling, determination of earthquake locations and focal mechanism. In this report, we use teleseismic receiver function to invert the S-velocity model beneath a seismic station located in the Cimandiri fault zone using neighbourhood algorithm inversion method. The result suggests the crustal thickness beneath the station is about 32-38 km. Furthermore, low velocity layers with high Vp/Vs exists in the lower crust, which may indicate the presence of hot material ascending from the subducted slab.

Microstructure of Reaction Zone Formed During Diffusion Bonding of TiAl with Ni/Al Multilayer

Science.gov (United States)

Simões, Sónia; Viana, Filomena; Koçak, Mustafa; Ramos, A. Sofia; Vieira, M. Teresa; Vieira, Manuel F.

2012-05-01

In this article, the characterization of the interfacial structure of diffusion bonding a TiAl alloy is presented. The joining surfaces were modified by Ni/Al reactive multilayer deposition as an alternative approach to conventional diffusion bonding. TiAl substrates were coated with alternated Ni and Al nanolayers. The nanolayers were deposited by dc magnetron sputtering with 14 nm of period (bilayer thickness). Joining experiments were performed at 900 °C for 30 and 60 min with a pressure of 5 MPa. Cross sections of the joints were prepared for characterization of their interfaces by scanning electron microscopy (SEM), transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), high resolution TEM (HRTEM), energy dispersive x-ray spectroscopy (EDS), and electron backscatter diffraction (EBSD). Several intermetallic compounds form at the interface, assuring the bonding of the TiAl. The interface can be divided into three distinct zones: zone 1 exhibits elongated nanograins, very small equiaxed grains are observed in zone 2, while zone 3 has larger equiaxed grains. EBSD analysis reveals that zone 1 corresponds to the intermetallic Al2NiTi and AlNiTi, and zones 2 and 3 to NiAl.

Receiver Function Imaging of Mantle Transition Zone Discontinuities Beneath Alaska

Science.gov (United States)

Dahm, Haider Hassan Faraj

Subduction of tectonic plates is one of the most important tectonic processes, yet many aspects of subduction zone geodynamics remain unsolved and poorly understood, such as the depth extent of the subducted slab and its geometry. The Alaska subduction zone, which is associated with the subduction of the Pacific Plate beneath the North America plate, has a complex tectonic setting and carries a series of subduction episodes, and represents an excellent target to study such plate tectonic processes. Previous seismological studies in Alaska have proposed different depth estimations and geometry for the subducted slab. The Mantle transition zone discontinuities of the 410km and the 660 km provide independent constraints on the depth extent of the subducted slabs. We conducted a receiver function study to map the topography of the 410 km and the 660 km discontinuities beneath Alaska and its adjacent areas by taking advantage of the teleseismic data from the new USArray deployment in Alaska and northwestern Canada. Stacking over 75,000 high-quality radial receiver functions recorded in Alaska with more than 40 years of recording period, the topographies of the 410 km and 660 km are mapped. The depths of both d410 and d660 show systematic spatial variations, the mean depth of d410 and d660 are within 6 km and 6 km from the global average, respectively. The mean MTZ thickness of the entire study area is within -2 km from the global average of 250 km, suggesting normal MTZ conditions on average. Central and south-central Alaska are characterized by a larger than normal MTZ thickness, suggesting that the subducting Pacific slab is thermally interacted with the MTZ. This study shows that lateral upper mantle velocity variations contribute the bulk of the observed apparent undulations of the MTZ discontinuities.

Correlation between epithelial thickness in normal corneas, untreated ectatic corneas, and ectatic corneas previously treated with CXL; is overall epithelial thickness a very early ectasia prognostic factor?

Science.gov (United States)

Kanellopoulos, Anastasios John; Aslanides, Ioannis M; Asimellis, George

2012-01-01

To determine and correlate epithelial corneal thickness (pachymetric) measurements taken with a digital arc scanning very high frequency ultrasound biomicroscopy (HF UBM) imaging system (Artemis-II), and compare mean and central epithelial thickness among normal eyes, untreated keratoconic eyes, and keratoconic eyes previously treated with collagen crosslinking (CXL). Epithelial pachymetry measurements (topographic mapping) were conducted on 100 subjects via HF UBM. Three groups of patients were included: patients with normal eyes (controls), patients with untreated keratoconic eyes, and patients with keratoconic eyes treated with CXL. Central, mean, and peripheral corneal epithelial thickness was examined for each group, and a statistical study was conducted. Mean, central, and peripheral corneal epithelial thickness was compared between the three groups of patients. Epithelium thickness varied substantially in the keratoconic group, and in some cases there was a difference of up to 20 μm between various points of the same eye, and often a thinner epithelium coincided with a thinner cornea. However, on average, data from the keratoconic group suggested an overall thickening of the epithelium, particularly over the pupil center of the order of +3 μm, while the mean epithelium thickness was on average +1.1 μm, compared to the control population (P = 0.005). This overall thickening was more pronounced in younger patients in the keratoconic group. Keratoconic eyes previously treated with CXL showed, on average, virtually the same average epithelium thickness (mean -0.7 μm, -0.2 μm over the pupil center, -0.9 μm over the peripheral zone) as the control group. This finding further reinforces our novel theory of the "reactive" component of epithelial thickening in corneas that are biomechanically unstable, becoming stable when biomechanical rigidity is accomplished despite persistence of cornea topographic irregularity. A highly irregular epithelium may be

The First Atmospheric Characterization of a Habitable-Zone Exoplanet

Science.gov (United States)

Stevenson, Kevin; Bean, Jacob; Charbonneau, David; Desert, Jean-Michel; Fortney, Jonathan; Irwin, Jonathan; Kreidberg, Laura; Line, Michael; Montet, Ben; Morley, Caroline

2015-10-01

Exoplanet surveys have recently revealed nearby planets orbiting within stellar habitable zones. This highly-anticipated breakthrough brings us one step closer in our quest to identify cosmic biosignatures, the indicators of extrasolar life. To achieve our goal, we must first study the atmospheres of these temperate worlds to measure their compositions and determine the prevalence of obscuring clouds. Using observations from the K2 mission, Co-I Montet recently announced the discovery of a 2.2 Earth-radii planet within the habitable zone of its relatively bright, nearby M dwarf parent star, K2-18. This temperate world is currently the best habitable-zone target for atmospheric characterization. Congruent with currently planned HST observations, we propose a Spitzer program to measure the transmission spectrum of the first habitable-zone exoplanet. Both telescopes are essential to revealing K2-18b's chemical composition. In a cloud-free, hydrogen-dominated atmosphere, the precision achieved by these measurements will be sufficient to detect methane, ammonia, and water vapor, which are the dominant C, N, and O bearing species at these temperatures. In turn, elemental abundance constraints from a primordial atmosphere can tell us about the composition of a protoplanetary disk in which Earth-like planets could have formed. Conversely, if the atmosphere contains thick clouds then the multi-wavelength observations from K2, HST, and Spitzer will constrain the clouds' properties. Because temperature plays a key role in the formation of clouds, their detection within the atmosphere of this habitable-zone exoplanet would be an important signpost that serves as a guide to future investigations of smaller, rocky exoplanets. As K2 continues discovering more habitable-zone planets, it is imperative that we perform spectral reconnaissance with Spitzer to determine their physical characteristics and begin understanding the prevalence of potentially-obscuring clouds prior to the

The effects of abdominal draw-in maneuver and core exercise on abdominal muscle thickness and Oswestry disability index in subjects with chronic low back pain.

Science.gov (United States)

Park, Seong-Doo; Yu, Seong-Hun

2013-04-01

The purpose of this study was to effects of abdominal draw-in maneuver and core exercise with 4 weeks using the musculoskeletal ultrasonography on muscle thickness and disability in subjects with low back pain. Twenty patients with nonspecific back pain (abdominal draw-in maneuver group: n= 10, core exercise group: n= 10) were recruited in the study. Both group received exercise intervention 3 times a week for 4weeks. The test were based on muscle thickness (transversus abdominis; Tra, internal oblique; IO and external oblique; EO), disability (Oswestry disability index; ODI) measured immediately before and after intervention. The data was measured by SPSS program 12.0 version and analyzed by Paired t-test and Independent t-test. The following results were obtained. The thickness of IO, EO for both group significantly improved except for muscle thickness of Tra. The ODI were significant difference for both groups. As the results of this study, we suggest that it may be effective method to apply to increase for the thickness of Tra, EO using abdominal draw-in maneuver and thickness of IO using core exercise.

Thermal structure and geodynamics of subduction zones

Science.gov (United States)

Wada, Ikuko

The thermal structure of subduction zones depends on the age-controlled thermal state of the subducting slab and mantle wedge flow. Observations indicate that the shallow part of the forearc mantle wedge is stagnant and the slab-mantle interface is weakened. In this dissertation, the role of the interface strength in controlling mantle wedge flow, thermal structure, and a wide range of subduction zone processes is investigated through two-dimensional finite-element modelling and a global synthesis of geological and geophysical observations. The model reveals that the strong temperature-dependence of the mantle strength always results in full slab-mantle decoupling along the weakened part of the interface and hence complete stagnation of the overlying mantle. The interface immediately downdip of the zone of decoupling is fully coupled, and the overlying mantle is driven to flow at a rate compatible with the subduction rate. The sharpness of the transition from decoupling to coupling depends on the rheology assumed and increases with the nonlinearity of the flow system. This bimodal behaviour of the wedge flow gives rise to a strong thermal contrast between the cold stagnant and hot flowing parts of the mantle wedge. The maximum depth of decoupling (MDD) thus dictates the thermal regime of the forearc. Observed surface heat flow patterns and petrologically and geochemically estimated mantle wedge temperatures beneath the volcanic arc require an MDD of 70--80 km in most, if not all, subduction zones regardless of their thermal regime of the slab. The common MDD of 70--80 km explains the observed systematic variations of the petrologic, seismological, and volcanic processes with the thermal state of the slab and thus explains the rich diversity of subduction zones in a unified fashion. Models for warm-slab subduction zones such as Cascadia and Nankai predict shallow dehydration of the slab beneath the cold stagnant part of the mantle wedge, which provides ample fluid

Effect of Extracorporeal Shock Wave Treatment on Deep Partial-Thickness Burn Injury in Rats: A Pilot Study

Directory of Open Access Journals (Sweden)

Gabriel Djedovic

2014-01-01

Full Text Available Extracorporeal shock wave therapy (ESWT enhances tissue vascularization and neoangiogenesis. Recent animal studies showed improved soft tissue regeneration using ESWT. In most cases, deep partial-thickness burns require skin grafting; the outcome is often unsatisfactory in function and aesthetic appearance. The aim of this study was to demonstrate the effect of ESWT on skin regeneration after deep partial-thickness burns. Under general anesthesia, two standardized deep partial-thickness burns were induced on the back of 30 male Wistar rats. Immediately after the burn, ESWT was given to rats of group 1 (N=15, but not to group 2 (N=15. On days 5, 10, and 15, five rats of each group were analyzed. Reepithelialization rate was defined, perfusion units were measured, and histological analysis was performed. Digital photography was used for visual documentation. A wound score system was used. ESWT enhanced the percentage of wound closure in group 1 as compared to group 2 (P<0.05. The reepithelialization rate was improved significantly on day 15 (P<0.05. The wound score showed a significant increase in the ESWT group. ESWT improves skin regeneration of deep partial-thickness burns in rats. It may be a suitable and cost effective treatment alternative in this type of burn wounds in the future.

The Effect of Subepithelial Connective Tissue Graft Placement on Esthetic Outcomes After Immediate Implant Placement: Systematic Review.

Science.gov (United States)

Lee, Chun-Teh; Tao, Chih-Yun; Stoupel, Janet

2016-02-01

Immediate implantation, despite many advantages, carries a risk of gingival recession, papilla loss, collapse of ridge contour, and other esthetic complications. Soft tissue graft placement combined with immediate implantation may be used to reduce these concerns. This review aims to systematically analyze clinical esthetic outcomes of the immediate implant combined with soft tissue graft (IMITG). The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for systematic reviews were used. The electronic search was conducted using MEDLINE (PubMed), EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) from January 1980 to October 2014. Quality assessments of selected articles were performed. Mid-buccal gingival level, interproximal gingival level, facial gingival thickness, gingival ridge dimension, and width of keratinized gingiva were the esthetic outcomes reviewed. Weighted mean difference of mid-buccal gingival level (WDBGL), papilla index score (WDPIS), and width of keratinized gingiva (WDKG) between initial and last measurements were calculated. Other esthetic outcomes were assessed by the descriptive analysis. Ten studies with a minimum of 6-month follow-up were included, and reported esthetic outcomes were analyzed. Mid-buccal gingival level (WDBGL, 0.07 mm; 95% confidence interval [CI] = -0.44 to 0.59; P = 0.12) and interproximal gingival level did not significantly change after IMITG (WDPIS in the mesial site, 0.31; 95% CI = -0.01 to 0.64; P = 0.06; and WDPIS in the distal site, 0.29; 95% CI = -0.06 to 0.65; P = 0.11). Width of keratinized gingiva significantly increased after IMITG (WDKG, 1.27 mm; 95% CI = -0.08 to 2.46; P = 0.04). Facial gingival thickness and gingival ridge dimension could be increased after IMITG. Because of the heterogeneity and limited number of selected studies, no conclusive statement could be made regarding the benefit of IMITG on esthetic outcomes. More randomized controlled trials

Definition of Management Zones for Enhancing Cultivated Land Conservation Using Combined Spatial Data

Science.gov (United States)

Li, Yan; Shi, Zhou; Wu, Hao-Xiang; Li, Feng; Li, Hong-Yi

2013-10-01

The loss of cultivated land has increasingly become an issue of regional and national concern in China. Definition of management zones is an important measure to protect limited cultivated land resource. In this study, combined spatial data were applied to define management zones in Fuyang city, China. The yield of cultivated land was first calculated and evaluated and the spatial distribution pattern mapped; the limiting factors affecting the yield were then explored; and their maps of the spatial variability were presented using geostatistics analysis. Data were jointly analyzed for management zone definition using a combination of principal component analysis with a fuzzy clustering method, two cluster validity functions were used to determine the optimal number of cluster. Finally one-way variance analysis was performed on 3,620 soil sampling points to assess how well the defined management zones reflected the soil properties and productivity level. It was shown that there existed great potential for increasing grain production, and the amount of cultivated land played a key role in maintaining security in grain production. Organic matter, total nitrogen, available phosphorus, elevation, thickness of the plow layer, and probability of irrigation guarantee were the main limiting factors affecting the yield. The optimal number of management zones was three, and there existed significantly statistical differences between the crop yield and field parameters in each defined management zone. Management zone I presented the highest potential crop yield, fertility level, and best agricultural production condition, whereas management zone III lowest. The study showed that the procedures used may be effective in automatically defining management zones; by the development of different management zones, different strategies of cultivated land management and practice in each zone could be determined, which is of great importance to enhance cultivated land conservation

Correlation between epithelial thickness in normal corneas, untreated ectatic corneas, and ectatic corneas previously treated with CXL; is overall epithelial thickness a very early ectasia prognostic factor?

Directory of Open Access Journals (Sweden)

Kanellopoulos AJ

2012-05-01

Full Text Available Anastasios John Kanellopoulos,1,2 Ioannis M Aslanides,3 George Asimellis11Laservision Eye Institute, Athens, 2Emmetropia Mediterranean Eye Clinic, Crete, Greece, 3New York University School of Medicine, NY, USAPurpose: To determine and correlate epithelial corneal thickness (pachymetric measurements taken with a digital arc scanning very high frequency ultrasound biomicroscopy (HF UBM imaging system (Artemis-II, and compare mean and central epithelial thickness among normal eyes, untreated keratoconic eyes, and keratoconic eyes previously treated with collagen crosslinking (CXL.Methods: Epithelial pachymetry measurements (topographic mapping were conducted on 100 subjects via HF UBM. Three groups of patients were included: patients with normal eyes (controls, patients with untreated keratoconic eyes, and patients with keratoconic eyes treated with CXL. Central, mean, and peripheral corneal epithelial thickness was examined for each group, and a statistical study was conducted.Results: Mean, central, and peripheral corneal epithelial thickness was compared between the three groups of patients. Epithelium thickness varied substantially in the keratoconic group, and in some cases there was a difference of up to 20 µm between various points of the same eye, and often a thinner epithelium coincided with a thinner cornea. However, on average, data from the keratoconic group suggested an overall thickening of the epithelium, particularly over the pupil center of the order of +3 µm, while the mean epithelium thickness was on average +1.1 µm, compared to the control population (P = 0.005. This overall thickening was more pronounced in younger patients in the keratoconic group. Keratoconic eyes previously treated with CXL showed, on average, virtually the same average epithelium thickness (mean –0.7 µm, –0.2 µm over the pupil center, –0.9 µm over the peripheral zone as the control group. This finding further reinforces our novel theory of the

Zone separator for multiple zone vessels

Science.gov (United States)

Jones, John B.

1983-02-01

A solids-gas contact vessel, having two vertically disposed distinct reaction zones, includes a dynamic seal passing solids from an upper to a lower zone and maintaining a gas seal against the transfer of the separate treating gases from one zone to the other, and including a stream of sealing fluid at the seal.

Effect of Hydrograph Separation on Suspended Sediment Concentration Predictions in a Forested Headwater with Thick Soil and Weathered Gneiss Layers

Directory of Open Access Journals (Sweden)

Naoki Kabeya

2014-06-01

Full Text Available Two-component hydrograph separation using oxygen-18 concentrations was conducted at a sediment runoff observation weir installed in a small subcatchment of a forested gneiss catchment in Japan. The mean soil thickness of this catchment is 7.27 m, which comprises 3.29 m of brown forest soil (A and B layers and a 3.98-m layer of heavily weathered gneiss. Data were collected for a storm on 20–21 May 2003, and the percentage of event water separated by the stable isotope ratio in comparison with the total rainfall amount was about 1%. This value is within the ratio of a riparian zone in a drainage area. Temporal variation of suspended sediment concentration exhibited higher correlation with the event water component than with the total runoff or pre-event water component. This shows that the riparian zone causes rainwater to flow out quickly during a rain event, and that this is an important area of sediment production and transportation in a forested headwater with thick soil and weathered gneiss layers.

Short-term and long-term Vadose zone monitoring: Current technologies, development, and applications

International Nuclear Information System (INIS)

Faybishenko, Boris

1999-01-01

At Hanford, Savannah River, Oak Ridge, Idaho National Engineering and Environmental Laboratory (INEEL), and other DOE sites, field vadose zone observations have shown complex water seepage and mass transport behavior in a highly heterogeneous, thick vadose zone on a variety of scales. Recent investigation showed that severe contamination of soils and groundwater by organic contaminant and nuclear waste occurred because of water seepage and contaminant transport along localized, preferential, fast flow within the heterogeneous vadose zone. However, most of the existing characterization and monitoring methods are not able to locate these localized and persistent preferential pathways associated with specific heterogeneous geologic features, such as clastic dikes, caliche layers, or fractures. In addition, changes in the chemical composition of moving and indigenous solutes, particularly sodium concentration, redox conditions, biological transformation of organic materials, and high temperature, may significantly alter water, chemicals, and bio-transformation exchange between the zones of fast flow and the rest of the media. In this paper, using the data from Hanford and INEEL sites, we will (1) present evidence that central problems of the vadose zone investigations are associated with preferential, fast flow phenomena and accelerated migration of organic and radioactive elements, (2) identify gaps in current characterization and monitoring technologies, and (3) recommend actions for the development of advanced vadose zone characterization and monitoring methods using a combination of hydrologic, geochemical, and geophysical techniques

Investigating the effect of tablet thickness and punch curvature on density distribution using finite elements method.

Science.gov (United States)

Diarra, Harona; Mazel, Vincent; Busignies, Virginie; Tchoreloff, Pierre

2015-09-30

Finite elements method was used to study the influence of tablet thickness and punch curvature on the density distribution inside convex faced (CF) tablets. The modeling of the process was conducted on 2 pharmaceutical excipients (anhydrous calcium phosphate and microcrystalline cellulose) by using Drucker-Prager Cap model in Abaqus(®) software. The parameters of the model were obtained from experimental tests. Several punch shapes based on industrial standards were used. A flat-faced (FF) punch and 3 convex faced (CF) punches (8R11, 8R8 and 8R6) with a diameter of 8mm were chosen. Different tablet thicknesses were studied at a constant compression force. The simulation of the compaction of CF tablets with increasing thicknesses showed an important change on the density distribution inside the tablet. For smaller thicknesses, low density zones are located toward the center. The density is not uniform inside CF tablets and the center of the 2 faces appears with low density whereas the distribution inside FF tablets is almost independent of the tablet thickness. These results showed that FF and CF tablets, even obtained at the same compression force, do not have the same density at the center of the compact. As a consequence differences in tensile strength, as measured by diametral compression, are expected. This was confirmed by experimental tests. Copyright © 2015 Elsevier B.V. All rights reserved.

High-Resolution P'P' Precursor Imaging of Nazca-South America Plate Boundary Zones and Inferences for Transition Zone Temperature and Composition

Science.gov (United States)

Gu, Y. J.; Schultz, R.

2013-12-01

Knowledge of upper mantle transition zone stratification and composition is highly dependent on our ability to efficiently extract and properly interpret small seismic arrivals. A promising high-frequency seismic phase group particularly suitable for a global analysis is P'P' precursors, which are capable of resolving mantle structures at vertical and lateral resolution of approximately 5 and 200 km, respectively, owing to their shallow incidence angle and small, quasi-symmetric Fresnel zones. This study presents a simultaneous analysis of SS and P'P' precursors based on deconvolution, Radon transform and depth migration. Our multi-resolution survey of the mantle near Nazca-South America subduction zone reveals both olivine and garnet related transitions at depth below 400 km. We attribute a depressed 660 to thermal variations, whereas compositional variations atop the upper-mantle transition zone are needed to explain the diminished or highly complex reflected/scattered signals from the 410 km discontinuity. We also observe prominent P'P' reflections within the transition zone, especially near the plate boundary zone where anomalously high reflection amplitudes result from a sharp (~10 km thick) mineral phase change resonant with the dominant frequency of the P'P' precursors. Near the base of the upper mantle, the migration of SS precursors shows no evidence of split reflections near the 660-km discontinuity, but potential majorite-ilmenite (590-640 km) and ilmenite-perovskite transitions (740-750 km) are identified based on similarly processed high-frequency P'P' precursors. At nominal mantle temperatures these two phase changes may be seismically indistinguishable, but colder mantle conditions from the descending Nazca plate, the presence of water and variable Fe contents may cause sufficient separation for a reliable analysis. In addition, our preliminary results provide compelling evidence for multiple shallow lower-mantle reflections (at ~800 km) along the

The transition zone above a lumbosacral fusion.

Science.gov (United States)

Hambly, M F; Wiltse, L L; Raghavan, N; Schneiderman, G; Koenig, C

1998-08-15

The clinical and radiographic effect of a lumbar or lumbosacral fusion was studied in 42 patients who had undergone a posterolateral fusion with an average follow-up of 22.6 years. To examine the long-term effects of posterolateral lumbar or lumbosacral fusion on the cephalad two motion segments (transition zone). It is commonly held that accelerated degeneration occurs in the motion segments adjacent to a fusion. Most studies are of short-term, anecdotal, uncontrolled reports that pay particular attention only to the first motion segment immediately cephalad to the fusion. Forty-two patients who had previously undergone a posterolateral lumbar or lumbosacral fusion underwent radiographic and clinical evaluation. Rate of fusion, range of motion, osteophytes, degenerative spondylolisthesis, retrolisthesis, facet arthrosis, disc ossification, dynamic instability, and disc space height were all studied and statistically compared with an age- and gender-matched control group. The patient's self-reported clinical outcome was also recorded. Degenerative changes occurred at the second level above the fused levels with a frequency equal to those occurring in the first level. There was no statistical difference between the study group and the cohort group in the presence of radiographic changes within the transition zone. In those patients undergoing fusion for degenerative processes, 75% reported a good to excellent outcome, whereas 84% of those undergoing fusion for spondylolysis or spondylolisthesis reported a good to excellent outcome. Radiographic changes occur within the transition zone cephalad to a lumbar or lumbosacral fusion. However, these changes are also seen in control subjects who have had no surgery.

Hydrogeological impact of fault zones on a fractured carbonate aquifer, Semmering (Austria)

Science.gov (United States)

Mayaud, Cyril; Winkler, Gerfried; Reichl, Peter

2015-04-01

Fault zones are the result of tectonic processes and are geometrical features frequently encountered in carbonate aquifer systems. They can hamper the fluid migration (hydrogeological barriers), propagate the movement of fluid (draining conduits) or be a combination of both processes. Numerical modelling of fractured carbonate aquifer systems is strongly bound on the knowledge of a profound conceptual model including geological and tectonic settings such as fault zones. In further consequence, numerical models can be used to evaluate the conceptual model and its introduced approximations. The study was conducted in a fractured carbonate aquifer built up by permomesozoic dolo/limestones of the Semmering-Wechsel complex in the Eastern Alps (Austria). The aquifer has an assumed thickness of about 200 m and dips to the north. It is covered by a thin quartzite layer and a very low permeable layer of quartz-phyllite having a thickness of up to several hundred meters. The carbonate layer crops out only in the southern part of the investigation area, where it receives autogenic recharge. The geological complexity affects some uncertainties related to the extent of the model area, which was determined to be about 15 km². Three vertical fault zones cross the area approximately in a N-S direction. The test site includes an infrastructural pilot tunnel gallery of 4.3 km length with two pumping stations, respectively active since August 1997 and June 1998. The total pumping rate is about 90 l/s and the drawdown data were analysed analytically, providing a hydraulic conductivity of about 5E-05 m/s for the carbonate layer. About 120 m drawdown between the initial situation and situation with pumping is reported by piezometers. This led to the drying up of one spring located at the southern border of the carbonates. A continuum approach using MODFLOW-2005 was applied to reproduce numerically the observed aquifer behaviour and investigate the impact of the three fault zones. First

The influence of the Al stabilizer layer thickness on the normal zone propagation velocity in high current superconductors

CERN Document Server

Shilon, I.; Langeslag, S.A.E.; Martins, L.P.; ten Kate, H.H.J.

2015-06-19

The stability of high-current superconductors is challenging in the design of superconducting magnets. When the stability requirements are fulfilled, the protection against a quench must still be considered. A main factor in the design of quench protection systems is the resistance growth rate in the magnet following a quench. The usual method for determining the resistance growth in impregnated coils is to calculate the longitudinal velocity with which the normal zone propagates in the conductor along the coil windings. Here, we present a 2D numerical model for predicting the normal zone propagation velocity in Al stabilized Rutherford NbTi cables with large cross section. By solving two coupled differential equations under adiabatic conditions, the model takes into account the thermal diffusion and the current redistribution process following a quench. Both the temperature and magnetic field dependencies of the superconductor and the metal cladding materials properties are included. Unlike common normal zon...

Investigation of (n,γ) reaction in hybrid reactor zones

International Nuclear Information System (INIS)

Guenay, Mehtap

2014-01-01

In this study, the fluids were composed with increased mole fractions of a mixture of molten salt: heavy metals 99-95 % Li 20 Sn 80 - 1-5 % SFG-Pu, 99-95 % Li 20 Sn 80 - 1-5 % SFG-PuF 4 , 99-95 % Li 20 Sn 80 - 1-5 % SFG-PuO 2 . In this study, the effect on conversion of each isotope ( 238-242 Pu) in spent fuel grade plutonium by (n,γ) reactions was investigated in liquid first wall, blanket and shield zones of the designed hybrid reactor system. Beryllium (Be) is the neutron multiplier by (n,2n) reactions. The Be zone used was 3 cm thick. 9Cr2WVT, a ferritic steel, is used as structural material. Three-dimensional nucleonic calculations were performed by using the most recent versions of the MCNPX-2.7.0 Monte Carlo code and the nuclear data library ENDF/B-VII.0.

Investigation of (n,γ) reaction in hybrid reactor zones

Energy Technology Data Exchange (ETDEWEB)

Guenay, Mehtap [Inoenue Univ., Malatya (Turkey). Physics Dept.

2014-12-15

In this study, the fluids were composed with increased mole fractions of a mixture of molten salt: heavy metals 99-95 % Li{sub 20}Sn{sub 80{sup -}}1-5 % SFG-Pu, 99-95 % Li{sub 20}Sn{sub 80{sup -}}1-5 % SFG-PuF{sub 4}, 99-95 % Li{sub 20}Sn{sub 80{sup -}}1-5 % SFG-PuO{sub 2}. In this study, the effect on conversion of each isotope ({sup 238-242}Pu) in spent fuel grade plutonium by (n,γ) reactions was investigated in liquid first wall, blanket and shield zones of the designed hybrid reactor system. Beryllium (Be) is the neutron multiplier by (n,2n) reactions. The Be zone used was 3 cm thick. 9Cr2WVT, a ferritic steel, is used as structural material. Three-dimensional nucleonic calculations were performed by using the most recent versions of the MCNPX-2.7.0 Monte Carlo code and the nuclear data library ENDF/B-VII.0.

Static and dynamic through thickness lamina properties of thick laminates

NARCIS (Netherlands)

Lahuerta, F.; Nijssen, R.P.L.; Van der Meer, F.P.; Sluys, L.J.

2015-01-01

Thick laminates are increasingly present in large composites structures such as wind turbine blades. Different factors are suspected to be involved in the decreased static and dynamic performance of thick laminates. These include the effect of self-heating, the scaling effect, and the manufacturing

Shifts in the distribution of rural population in the non-Chernozem zone of the RSFSR.

Science.gov (United States)

Igudina, A I; Ioffe, G V

1986-04-01

"Rural population change within the Non-Chernozem zone of the RSFRS [Russian Soviet Federated Socialist Republic] is examined over the period 1959-79 at several levels of analysis: the Non-Chernozem zone as a whole, its major economic regions, individual oblasts, individual rayons and individual farms and rural places. The overriding tendency at all levels of analysis has been the increasing spatial concentration of rural population." The authors observe that "this concentration assumes a variety of forms, from the concentration of rural population in the suburban zones of large cities and the immediate surroundings of rayon seats to a decline in the number of rural places (from 180,000 in 1959 to 118,000 in 1979) and the growth of local centers against a general background of rural population decline. The authors hint that the observed tendency is a positive development, in keeping with the policy of converting Soviet agriculture to a more intensive path of development." excerpt

Nuclear-waste isolation in the unsaturated zone of arid regions

International Nuclear Information System (INIS)

Wollenberg, H.A.; Wang, J.S.Y.; Korbin, G.

1982-05-01

The vadose zone in arid regions is considered as a possible environment for geologic isolation of nuclear waste. There are several topographic and lithologic combinations in the vadose zone of arid regions that may lend themselves to waste isolation considerations. In some cases, topographic highs such as mesas and interbasin ranges - comprised of several rock types, may contain essentially dry or partially saturated conditions favorable for isolation. The adjacent basins, especially in the far western and southwestern US, may have no surface or subsurface hydrologic connections with systems ultimately leading to the ocean. Some rock types may have the favorable characteristics of very low permeability and contain appropriate minerals for the strong chemical retardation of radionuclides. Environments exhibiting these hydrologic and geochemical attributes are the areas underlain by tuffaceous rocks, relatively common in the Basin and Range geomorphic province. Adjacent valley areas, where tuffaceous debris makes up a significant component of valley fill alluvium, may also contain thick zones of unsaturated material, and as such also lend themselves to strong consideration as respository environments. This paper summarizes the aspects of nuclear waste isolation in unsaturated regimes in alluvial-filled valleys and tuffaceous rocks of the Basin and Range province

Immediate Implant Placement into Extraction Sockets with Labial Plate Dehiscence Defects: A Clinical Case Series.

Science.gov (United States)

Sarnachiaro, Guido O; Chu, Stephen J; Sarnachiaro, Evangelina; Gotta, Sergio Luis; Tarnow, Dennis P

2016-08-01

To measure the buccal plate reconstruction of extraction sockets with labial plate dehiscence defects using a bone allograft in combination with an absorbable collagen membrane and a custom-healing abutment at the time of tooth removal. Ten patients underwent immediate implant placement and reconstruction of the buccal plate. Cone beam computed tomography (CBCT) was performed preextraction, immediately after bone grafting and implant placement (day 0), and between 6 and 9 months following implant surgery. Measurements were taken at three levels: coronal (L1), middle (L2), and apical (L3) level. Implants placed into sockets with labial plate dehiscence defects demonstrated radiographic reformation of the labial plate dehiscence defect at 6 to 9 months posttreatment. The net gain in labial plate on cone beam computerized tomography (CBCT) in L1 and L2 was 3.0 mm, where 0 mm existed at pretreatment. The minimum amount of labial plate thickness of 2.0 mm was achieved in all treated sites, evaluated radiographically at 6 to 9 months postoperatively, in a single procedure, without flap elevation and maintaining the gingival architecture and satisfactory esthetics. Placing an absorbable membrane, bone graft, and custom-healing abutment at the time of flapless anterior tooth extraction and immediate implant placement into a socket with a labial osseous dehiscence is a viable clinical technique to reconstitute the absence of the labial bone plate. © 2015 Wiley Periodicals, Inc.

Parapapillary atrophy: histological gamma zone and delta zone.

Directory of Open Access Journals (Sweden)

Jost B Jonas

Full Text Available BACKGROUND: To examine histomorphometrically the parapapillary region in human eyes. METHODOLOGY/PRINCIPAL FINDINGS: The histomorphometric study included 65 human globes (axial length:21-37 mm. On anterior-posterior histological sections, we measured the distance Bruch's membrane end (BME-optic nerve margin ("Gamma zone", BME-retinal pigment epithelium (RPE ("Beta zone", BME-beginning of non-occluded choriocapillaris, and BME-beginning of photoreceptor layer. "Delta zone" was defined as part of gamma zone in which blood vessels of at least 50 µm diameter were not present over a length of >300 µm. Beta zone (mean length:0.35±0.52 mm was significantly (P = 0.01 larger in the glaucoma group than in the non-glaucomatous group. It was not significantly (P = 0.28 associated with axial length. Beta zone was significantly (P = 0.004 larger than the region with occluded choriocapillaris. Gamma zone (mean length:0.63±1.25 mm was associated with axial length (P50 µm diameter within gamma zone was present only in highly axially elongated globes and was not related with glaucoma. Beta zone (Bruch's membrane without RPE was correlated with glaucoma but not with globe elongation. Since the region with occluded choriocapillaris was smaller than beta zone, complete loss of RPE may have occurred before complete choriocapillaris closure.

A Novel Application of the Multichannel Analysis of Surface Waves (MASW) Method for Estimating the Critical Zone Thicknes

Science.gov (United States)

Nelson, S.; Yaede, J.; McBride, J. H.; Park, C.; Turnbull, S. J.; Tingey, D. G.

2014-12-01

MASW approaches are suitable for the accurate measurement of variably thick weathering profiles by producing shear-wave (Vs) profiles. The critical zone (CZ) base is usually a transitional boundary, which is captured by MASW but not by conventional seismic reflection techniques. Modified MASW methods were used in Hawaii, USA to extend the investigative depth of saprolite (kaolin clays, Fe-oxides) thickness calibrated against wells with geologic logs. Active-source ± passive dispersion curves produced improved low-frequency fundamental modes by combining records with varying source-receiver offsets, enabling the generation of Vs profiles to >50 m depth. The top of unaltered bedrock occurs at a Vs of >~500 m/s. Intra-saprolite high Vs zones probably represent aa flow interiors with fewer primary discontinuities (vesicles and fractures), therefore imparting higher secondary stiffness than altered pahoehoe and pyroclastic material. The MASW approach permits measuring CZ thicknesses at discrete locations rapidly, inexpensively, and without drilling. For example, employed on slopes of the Koolau Volcano (neither aggrading nor degrading), the downward rate of advance of the weathering front of the CZ varies from 0.02 to 0.03 mm/yr in wet and ~0.01 mm/yr in dry areas. This compares well with recent work based on solute mass fluxes averaged over large areas. MASW can be deployed in a variety of settings where rapid estimation of the CZ thickness at particular locations is desired.

A global limit load solution for plates with surface cracks under combined end force and cross-thickness bending

International Nuclear Information System (INIS)

Lei Yuebao; Fox, Mike J.H.

2011-01-01

A global limit load solution for rectangular surface cracks in plates under combined end force and cross-thickness bending is derived, which allows any combination of positive/negative end force and positive/negative cross-thickness moment. The solution is based on the net-section plastic collapse concept and, therefore, gives limit load values based on the Tresca yielding criterion. Solutions for both cases with and without crack face contact are derived when whole or part of the crack is located in the compressive stress zone. From the solution, particular global limit load solutions for plates with extended surface cracks and through-thickness cracks under the same loading conditions are obtained. The solution is consistent with the limit load solution for surface cracks in plates under combined tension and positive bending due to Goodall and Webster and Lei when both the applied end force and bending moment are positive. The solution reduces to the limit load solution for plain plates under combined end force and cross-thickness bending when the crack vanishes. - Highlights: → A global limit load solution for plates with surface cracks in plates is derived. → Combined positive/negative end force and positive/negative cross-thickness moment are considered. → The solution is based on the net-section plastic collapse concept.

Nitrate Diffusional Releases from the Saltstone Facility, Vault 2, with Respect to Different Concrete Wall Thicknesses

International Nuclear Information System (INIS)

ROBERT, HIERGESELL

2005-01-01

To assist the Saltstone Vault 2 Design Team, an investigation was conducted to evaluate the effectiveness of alternative concrete wall thicknesses in limiting nitrate diffusion away from the planned facility. While the current design calls for 18-inch concrete walls, alternative thicknesses of 12-in, 8-in, and 6-in were evaluated using a simplified 1-D numerical model. To serve as a guide for Saltstone Vault 2 conceptual design, the results of this investigation were applied to Saltstone Vault 4 to determine what the hypothetical limits would be for concrete wall thicknesses thinner than the planned 18-inches. This was accomplished by adjusting the Vault 4 Limits, based on the increased nitrate diffusion rates through the thinner concrete walls, such that the 100-m well limit of 44 mg/L of nitrate as nitrate was not exceeded. The implication of these preliminary results is that as thinner vault walls are implemented there is a larger release of nitrate, thus necessitating optimal vault placement to minimize the number of vaults placed along a single groundwater flow path leading to the discharge zone

Effect Of Age And Concrete Cover Thickness On Steel Reinforcement Corrosion At Splash Zone In Reinforced Concrete Hydraulic Structures

Directory of Open Access Journals (Sweden)

Nada M. Al- Galawi

2015-08-01

Full Text Available Corrosion of reinforcing steel bars in reinforced concrete is considered as one of the biggest problems that face countries overlooking to the Arabian Gulf including Iraq. The research aims to study the effect of the corrosion of steel bars in concrete structures that are exposed to wetting and drying via waves. Reinforced concrete samples were exposed to marine simulated environment for 90 days using prepared system for this purpose. At the end of exposure period polarization test was implemented to measure the actual corrosion rate in each sample. After that the corrosion process was accelerated using impressed current technique by applying a constant electric current DC to the reinforcing bars. Depending on the corrosion current in natural conditions which was measured in polarization test periods of exposing samples to accelerated corrosion current so as to maintain virtual exposure ages of 5 and 25 years of exposure to natural corrosion were calculated. The results showed a remarkable increase in the corrosion current of steel bars in samples that had lower concrete cover thickness. The increase in the cover thickness from 20mm to 40 and 65 mm had a significant effect on reducing the corrosion current at the age of 90 days to about 70 of its original value in both cases. At the virtual exposure age of 5 years the reduction percentage in the corrosion current resulted from increasing cover thickness from 20mm to 40 and 65 mm were 43 and 79 respectively.

Fresnel zone-plate based X-ray microscopy in Zernike phase contrast with sub-50 nm resolution at NSRL

International Nuclear Information System (INIS)

Chen Jie; Li Wenjie; Tian Jinping; Liu Longhua; Xiong Ying; Liu Gang; Wu Ziyu; Tian Yangchao; Liu Yijin; Yue Zhengbo; Yu Hanqing; Wang Chunru

2009-01-01

A transmission X-ray microscope using Fresnel zone-plates (FZPs) has been installed at U7A beamline of National Synchrotron Radiation Laboratory (NSRL). The objective FZP with 45 nm outermost zone width delivers a sub-50 nm resolution. A gold phase ring with 2.5 μm thickness and 4 μm width was placed at the focal plane of the objective FZP at 8 keV to produce a negative Zernike phase contrast. A series of samples were used to test the performance of the Zernike phase contrast X-ray microscopy.

Fresnel zone-plate based X-ray microscopy in Zernike phase contrast with sub-50 nm resolution at NSRL

Energy Technology Data Exchange (ETDEWEB)

Chen Jie; Li Wenjie; Tian Jinping; Liu Longhua; Xiong Ying; Liu Gang; Wu Ziyu; Tian Yangchao [National Synchrotron Radiation Laboratory (China); Liu Yijin [School of Physics (China); Yue Zhengbo; Yu Hanqing [Laboratory of Environmental Engineering, School of Chemistry, University of Science and Technology of China, Hefei Anhui 230029 (China); Wang Chunru, E-mail: ychtian@ustc.edu.c [Institute of Chemistry, Chinese Academy of Sciences, Beijing 10060 (China)

2009-09-01

A transmission X-ray microscope using Fresnel zone-plates (FZPs) has been installed at U7A beamline of National Synchrotron Radiation Laboratory (NSRL). The objective FZP with 45 nm outermost zone width delivers a sub-50 nm resolution. A gold phase ring with 2.5 {mu}m thickness and 4 {mu}m width was placed at the focal plane of the objective FZP at 8 keV to produce a negative Zernike phase contrast. A series of samples were used to test the performance of the Zernike phase contrast X-ray microscopy.

A Simple Transmission Electron Microscopy Method for Fast Thickness Characterization of Suspended Graphene and Graphite Flakes.

Science.gov (United States)

Rubino, Stefano; Akhtar, Sultan; Leifer, Klaus

2016-02-01

We present a simple, fast method for thickness characterization of suspended graphene/graphite flakes that is based on transmission electron microscopy (TEM). We derive an analytical expression for the intensity of the transmitted electron beam I 0(t), as a function of the specimen thickness t (tgraphite). We show that in thin graphite crystals the transmitted intensity is a linear function of t. Furthermore, high-resolution (HR) TEM simulations are performed to obtain λ for a 001 zone axis orientation, in a two-beam case and in a low symmetry orientation. Subsequently, HR (used to determine t) and bright-field (to measure I 0(0) and I 0(t)) images were acquired to experimentally determine λ. The experimental value measured in low symmetry orientation matches the calculated value (i.e., λ=225±9 nm). The simulations also show that the linear approximation is valid up to a sample thickness of 3-4 nm regardless of the orientation and up to several ten nanometers for a low symmetry orientation. When compared with standard techniques for thickness determination of graphene/graphite, the method we propose has the advantage of being simple and fast, requiring only the acquisition of bright-field images.

Analysis of gaseous-phase stable and radioactive isotopes in the unsaturated zone, Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Yang, I.C.; Haas, H.H.; Weeks, E.P.; Thorstenson, D.C.

1985-01-01

The Nevada Nuclear Waste Storage Investigations Project of the US Department of Energy provides that agency with data for evaluating volcanic tuff beneath Yucca Mountain, Nevada, to determine its suitability for a potential repository of high-level radioactive waste. Thickness of the unsaturated zone, which consists of fractured, welded and nonwelded tuff, is about 1640 to 2460 feet (500 to 750 meters). One question to be resolved is an estimate of minimum ground-water traveltime from the disturbed zone of the potentail repository to the accessible environment. Another issue is the potential for diffusive or convective gaseous transport of radionuclides from an underground facility in the unsaturated zone to the accessible environment. Gas samples were collected at intervals to a depth of 1200 feet from the unsaturated zone at Yucca Mountain, Nevada. Samples were analyzed for major atmospheric gases; carbon dioxide in the samples was analyzed for carbon-14 activity and for delta 13 C; water vapor in the samples was analyzed for deuterium and oxygen-18. These data could provide insight into the nature of unsaturated zone transport processes. 15 refs., 4 figs., 4 tabs

Delineation of groundwater development potential zones in parts of marginal Ganga Alluvial Plain in South Bihar, Eastern India.

Science.gov (United States)

Saha, Dipankar; Dhar, Y R; Vittala, S S

2010-06-01

A part of the Gangetic Alluvial Plain covering 2,228 km(2), in the state of Bihar, is studied for demarcating groundwater development potential zones. The area is mainly agrarian and experiencing intensive groundwater draft to the tune of 0.12 million cubic metre per square kilometres per year from the Quaternary marginal alluvial deposits, unconformably overlain northerly sloping Precambrian bedrock. Multiparametric data on groundwater comprising water level, hydraulic gradient (pre- and post-monsoon), aquifer thickness, permeability, suitability of groundwater for drinking and irrigation and groundwater resources vs. draft are spatially analysed and integrated on a Geographical Information System platform to generate thematic layers. By integrating these layers, three zones have been delineated based on groundwater development potential. It is inferred that about 48% of the area covering northern part has high development potential, while medium and low development potential category covers 41% of the area. Further increase in groundwater extraction is not recommended for an area of 173 km(2), affected by over-exploitation. The replenishable groundwater resource available for further extraction has been estimated. The development potential enhances towards north with increase in thickness of sediments. Local deviations are due to variation of-(1) cumulative thickness of aquifers, (2) deeper water level resulting from localised heavy groundwater extraction and (3) aquifer permeability.

On the nature of the calcareous substrate of a ferromanganese crust from the Vityaz Fracture Zone, Central Indian Ridge: Inferences on palaeoceanography

Digital Repository Service at National Institute of Oceanography (India)

Guptha, M.V.S.; Banerjee, R.; Mergulhao, L.

A 15-cm-thick carbonate substrate encrusted with ferromanganese oxides from the Vityaz Fracture Zone, Central Indian Ridge was analysed to reconstruct the palaeoceanography of the region. Based on the calcareous nannoplankton assemblage, an early...

Non-contact radiation thickness gauge

International Nuclear Information System (INIS)

Tsujii, T.; Okino, T.

1983-01-01

A noncontact thickness gauge system for measuring the thickness of a material comprising a source of radiation, a detector for detecting the amount of radiation transmitted through the material which is a function of the absorptance and thickness of the material, a memory for storing the output signals of the detector and curve-defining parameters for a plurality of quadratic calibration curves which correspond to respective thickness ranges, and a processor for processing the signals and curve defining parameters to determine the thickness of the material. Measurements are made after precalibration to obtain calibration curves and these are stored in the memory, providing signals representative of a nominal thickness and an alloy compensation coefficient for the material. The calibration curve corresponding to a particular thickness range is selected and the curve compensated for drift; the material is inserted into the radiation path and the detector output signal processed with the compensated calibration curve to determine the thickness of the material. (author)

Environmental zoning of a forest Pacific reserve zone located in Cordoba department, colombian Caribe

International Nuclear Information System (INIS)

Henao Sarmiento, Jesus Eugenio; Cardenas Torres, Miguel Andres; Fajardo Patino, Alirio

2008-01-01

This work includes the completion of a proposed zoning of the Zona de Reserva Forestal del Pacifico (ZRFP) in jurisdiction of the department of Cordoba, which has allowed to establish the managing trends of the natural resources that have been implemented in the municipalities of Tierralta and Valencia, where the uses of the territory have opposite characteristics with the reason of being of these lands, that were originally mainly forest areas and reserves for providing useful wood resources, as well as protective areas, that might reach in the growth of the economy of the country. The offers of zoning use of the soils by vocation and occupation proposed by the Instituto Geografico Agustin Codazzi IGAC (2002) were analyzed in detail; these are the technical foundation for the subtractions, according to the Law 2 of 1959. The work of biotic characterization focuses in the forest refuges that shelter great biodiversity wealth for the region and the department. The results of the characterization and evaluation show that there is a significant deterioration of ecosystems and ecological communities of the territory because of multiple actions performed by man along history, which, besides exploiting the environmental offer, contravene in some extensions the natural vocation of the soils. Therefore, it's important to put in consideration that given the intensity of the width and lengthwise interventions realized in the ZRFP, nowadays only some areas of natural forest remain, especially in the buffer area of the Paramillo National Park and in mountain areas bordering the department of Antioquia, which demands immediate actions of preservation and restoration.

Thickness filters for gradient based multi-material and thickness optimization of laminated composite structures

DEFF Research Database (Denmark)

Sørensen, Rene; Lund, Erik

2015-01-01

This paper presents a new gradient based method for performing discrete material and thickness optimization of laminated composite structures. The novelty in the new method lies in the application of so-called casting constraints, or thickness filters in this context, to control the thickness...... variation throughout the laminate. The filters replace the layerwise density variables with a single continuous through-the-thickness design variable. Consequently, the filters eliminate the need for having explicit constraints for preventing intermediate void through the thickness of the laminate....... Therefore, the filters reduce both the number of constraints and design variables in the optimization problem. Based upon a continuous approximation of a unit step function, the thickness filters are capable of projecting discrete 0/1 values to the underlying layerwise or ”physical” density variables which...

Comparison of 120- and 140-μm SMILE Cap Thickness Results in Eyes With Thick Corneas.

Science.gov (United States)

Liu, Manli; Zhou, Yugui; Wu, Xianghua; Ye, Tiantian; Liu, Quan

2016-10-01

To evaluate clinical outcomes after small incision lenticule extraction (SMILE) with different cap thicknesses in thick corneas. Forty patients with central corneal thickness of more than 560 μm were recruited in this prospective, randomized, masked, paired-eye study. Patients were randomized to receive SMILE with a 120-μm cap thickness in 1 eye and 140-μm cap thickness in the other. Uncorrected and corrected distance visual acuity (CDVA), contrast sensitivity (CS), higher-order aberrations (HOAs), and morphologic modifications of corneal architecture were measured during the 3-month follow-up period. Postoperative refractive outcomes, visual outcomes, CS, and the changes in HOAs were similar between both groups. The persistence of brightly reflective particles in the corneal interface layer was 1388.6 ± 219.5/mm in eyes with 120-μm cap thickness and 54.7 ± 8.6/mm in eyes with 140-μm cap thickness (P line at the interface layer almost disappeared in all eyes with 140-μm cap thickness, and it still persisted in 43% of the fellow eyes at 3 months postoperatively. The anterior surfaces of lenticules in the 140-μm cap thickness group exhibited more smoothness than in the 120-μm cap thickness group. There was a lower level corneal wound-healing response after SMILE with a 140-μm cap thickness than with a 120-μm cap thickness, although the thickness of cap creation did not affect visual outcomes by 3 months postoperatively.

An Approach to the Crustal Thickness Inversion Problem

Science.gov (United States)

De Marchi, F.; Di Achille, G.

2017-12-01

We describe a method to estimate the crustal thickness of a planet and we apply it to Venus. As in the method of (Parker, 1972), modified by (Wieczorek & Phillips, 1998), the gravity field anomalies of a planet are assumed to be due to the combined effect of topography and relief on the crust-mantle interface. No assumptions on isostasy are necessary. In our case, rather than using the expansion of the powers of the relief in Taylor series, we model the gravitational field of topography/relief by means of a large number of prism-shaped masses covering the whole surface of the planet. Under the hypothesis that crustal and mantle densities are the same everywhere, we solve for the relief depths on the crust-mantle interface by imposing that observed and modeled gravity field at a certain reference spherical surface (external to the planet) must be equal. This method can be extended to the case of non-uniform densities. Finally, we calculate a map of the crustal thickness of Venus and compare our results with those predicted by previous work and with the global distribution of main geological features (e.g. rift zones, tesserae, coronae). We discuss the agremeent between our results and the main geodynamical and crustal models put forth to explain the origin of such features and the applicability of this method in the context of the mission VOX (Venus Origins Explore), proposed for NASA's NF4 call.

Time-resolved analysis of thickness-dependent dewetting and ablation of silver films upon nanosecond laser irradiation

International Nuclear Information System (INIS)

Qi, Dongfeng; Paeng, Dongwoo; Yeo, Junyeob; Kim, Eunpa; Wang, Letian; Grigoropoulos, Costas P.; Chen, Songyan

2016-01-01

Nanosecond pulsed laser dewetting and ablation of thin silver films is investigated by time-resolved imaging. Laser pulses of 532 nm wavelength and 5 ns temporal width are irradiated on silver films of different thicknesses (50 nm, 80 nm, and 350 nm). Below the ablation threshold, it is observed that the dewetting process does not conclude until 630 ns after the laser irradiation for all samples, forming droplet-like particles in the spot central region. At higher laser intensities, ablative material removal occurs in the spot center. Cylindrical rims are formed in the peripheral dewetting zone due to the solidification of transported matter at about 700 ns following the laser pulse exposure. In addition to these features, droplet fingers are superposed upon irradiation of 350-nm thick silver films with higher intensity.

Time-resolved analysis of thickness-dependent dewetting and ablation of silver films upon nanosecond laser irradiation

Energy Technology Data Exchange (ETDEWEB)

Qi, Dongfeng [Laser Thermal Laboratory, Department of Mechanical Engineering, University of California, Berkeley, California 94720-1740 (United States); Semiconductor Photonics Research Center, Department of Physics, Xiamen University, Xiamen 361005 (China); Paeng, Dongwoo; Yeo, Junyeob; Kim, Eunpa; Wang, Letian; Grigoropoulos, Costas P., E-mail: cgrigoro@berkeley.edu [Laser Thermal Laboratory, Department of Mechanical Engineering, University of California, Berkeley, California 94720-1740 (United States); Chen, Songyan [Semiconductor Photonics Research Center, Department of Physics, Xiamen University, Xiamen 361005 (China)

2016-05-23

Nanosecond pulsed laser dewetting and ablation of thin silver films is investigated by time-resolved imaging. Laser pulses of 532 nm wavelength and 5 ns temporal width are irradiated on silver films of different thicknesses (50 nm, 80 nm, and 350 nm). Below the ablation threshold, it is observed that the dewetting process does not conclude until 630 ns after the laser irradiation for all samples, forming droplet-like particles in the spot central region. At higher laser intensities, ablative material removal occurs in the spot center. Cylindrical rims are formed in the peripheral dewetting zone due to the solidification of transported matter at about 700 ns following the laser pulse exposure. In addition to these features, droplet fingers are superposed upon irradiation of 350-nm thick silver films with higher intensity.

Facile Route to Vertically Aligned High-Aspect Ratio Block Copolymer Films via Dynamic Zone Annealing

Science.gov (United States)

Singh, Gurpreet; Kulkarni, Manish; Yager, Kevin; Smilgies, Detlef; Bucknall, David; Karim, Alamgir

2012-02-01

Directed assembly of block copolymers (BCP) can be used to fabricate a diversity of nanostructures useful for nanotech applications. The ability to vertically orient etchable high aspect ratio (˜30) ordered BCP domains on flexible substrates via continuous processing methods are particularly attractive for nanomanufacturing. We apply sharp dynamic cold zone annealing (CZA-S) to create etchable, and predominantly vertically oriented 30nm cylindrical domains in 1 μm thick poly(styrene-b-methylmethacrylate) films on low thermal conductivity rigid (quartz) and flexible (PDMS & Kapton) substrates. Under similar static conditions, temporally stable vertical cylinders form within a narrow zone above a critical temperature gradient. Primary ordering mechanism of CZA-S involves sweeping this vertically orienting zone created at maximum thermal gradient. An optimal speed is needed since the process competes with preferential surface wetting dynamics that favors parallel orientation. GISAXS of etched BCP films confirms internal morphology.

AUTOMATIC THICKNESS AND VOLUME ESTIMATION OF SPRAYED CONCRETE ON ANCHORED RETAINING WALLS FROM TERRESTRIAL LIDAR DATA

Directory of Open Access Journals (Sweden)

J. Martínez-Sánchez

2016-06-01

Full Text Available When ground conditions are weak, particularly in free formed tunnel linings or retaining walls, sprayed concrete can be applied on the exposed surfaces immediately after excavation for shotcreting rock outcrops. In these situations, shotcrete is normally applied conjointly with rock bolts and mesh, thereby supporting the loose material that causes many of the small ground falls. On the other hand, contractors want to determine the thickness and volume of sprayed concrete for both technical and economic reasons: to guarantee their structural strength but also, to not deliver excess material that they will not be paid for. In this paper, we first introduce a terrestrial LiDAR-based method for the automatic detection of rock bolts, as typically used in anchored retaining walls. These ground support elements are segmented based on their geometry and they will serve as control points for the co-registration of two successive scans, before and after shotcreting. Then we compare both point clouds to estimate the sprayed concrete thickness and the expending volume on the wall. This novel methodology is demonstrated on repeated scan data from a retaining wall in the city of Vigo (Spain, resulting in a rock bolts detection rate of 91%, that permits to obtain a detailed information of the thickness and calculate a total volume of 3597 litres of concrete. These results have verified the effectiveness of the developed approach by increasing productivity and improving previous empirical proposals for real time thickness estimation.

Automatic Thickness and Volume Estimation of Sprayed Concrete on Anchored Retaining Walls from Terrestrial LIDAR Data

Science.gov (United States)

Martínez-Sánchez, J.; Puente, I.; GonzálezJorge, H.; Riveiro, B.; Arias, P.

2016-06-01

When ground conditions are weak, particularly in free formed tunnel linings or retaining walls, sprayed concrete can be applied on the exposed surfaces immediately after excavation for shotcreting rock outcrops. In these situations, shotcrete is normally applied conjointly with rock bolts and mesh, thereby supporting the loose material that causes many of the small ground falls. On the other hand, contractors want to determine the thickness and volume of sprayed concrete for both technical and economic reasons: to guarantee their structural strength but also, to not deliver excess material that they will not be paid for. In this paper, we first introduce a terrestrial LiDAR-based method for the automatic detection of rock bolts, as typically used in anchored retaining walls. These ground support elements are segmented based on their geometry and they will serve as control points for the co-registration of two successive scans, before and after shotcreting. Then we compare both point clouds to estimate the sprayed concrete thickness and the expending volume on the wall. This novel methodology is demonstrated on repeated scan data from a retaining wall in the city of Vigo (Spain), resulting in a rock bolts detection rate of 91%, that permits to obtain a detailed information of the thickness and calculate a total volume of 3597 litres of concrete. These results have verified the effectiveness of the developed approach by increasing productivity and improving previous empirical proposals for real time thickness estimation.

Thickness-Dependent Bioelectrochemical and Energy Applications of Thickness-Controlled Meso-Macroporous Antimony-Doped Tin Oxide

Directory of Open Access Journals (Sweden)

Daniel Mieritz

2018-04-01

Full Text Available Coatings of hierarchically meso-macroporous antimony-doped tin oxide (ATO enable interfacing adsorbed species, such as biomacromolecules, with an electronic circuit. The coating thickness is a limiting factor for the surface coverage of adsorbates, that are electrochemically addressable. To overcome this challenge, a carbon black-based templating method was developed by studying the composition of the template system, and finding the right conditions for self-standing templates, preventing the reaction mixture from flowing out of the mask. The thicknesses of as-fabricated coatings were measured using stylus profilometry to establish a relationship between the mask thickness and the coating thickness. Cyclic voltammetry was performed on coatings with adsorbed cytochrome c to check whether the entire coating thickness was electrochemically addressable. Further, bacterial photosynthetic reaction centers were incorporated into the coatings, and photocurrent with respect to coating thickness was studied. The template mixture required enough of both carbon black and polymer, roughly 7% carbon black and 6% poly(ethylene glycol. Coatings were fabricated with thicknesses approaching 30 µm, and thickness was shown to be controllable up to at least 15 µm. Under the experimental conditions, photocurrent was found to increase linearly with the coating thickness, up to around 12 µm, above which were diminished gains.

Marine Geophysical Characterization of the Chain Fracture Zone in the Equatorial Atlantic

Science.gov (United States)

Harmon, N.; Rychert, C.; Agius, M. R.; Tharimena, S.; Kendall, J. M.

2017-12-01

The Chain Fracture zone is part of a larger system of fracture zones along the Mid Atlantic Ridge that is thought to be one of the original zones of weakness during the break up of Pangea. It is over 300 km long and produces earthquakes as large as Mw 6.9 on segments of the active fault zone. Here we present the results of two marine geophysical mapping campaigns over the active part of the Chain Fracture zone as part of the PI-LAB (Passive Imaging of the Lithosphere-Asthenosphere Boundary) experiment. We collected swath bathymetry, backscatter imagery, gravity and total field magnetic anomaly. We mapped the fault scarps within the transform fault system using the 50 m resolution swath and backscatter imagery. In addition, a 30-40 mGal residual Mantle Bouguer Anomaly determined from gravity analysis suggests the crust is by up to 1.4-2.0 km beneath the Chain relative to the adjacent ridge segments. However, in the eastern 75 km of the active transform we find evidence for thicker crust. The active fault system cuts through the region of thicker crust and there is a cluster of MW > 6 earthquakes in this region. There is a cluster of similar sized earthquakes on the western end where thinner crust is inferred. This suggests that variations in melt production and crustal thickness at the mid ocean ridge systems may have only a minor effect on the seismicity and longevity of the transform fault system.

Underwater cutting of reactor core internals by CO laser using local-dry-zone creating nozzle

Energy Technology Data Exchange (ETDEWEB)

Matsumoto, Osa (Mitsubishi Heavy Industries Ltd., Takasago, Hyogo (Japan). Takasago Research and Development Center); Sugihara, Masaaki; Miya, Kenzo

1992-11-01

With a view to practical application of the CO laser to underwater cutting of thick steel plates, a nozzle for creating a local dry zone on the workpiece has been developed and tested. The nozzle directed against the workpiece surface discharges a jet of air, which forms the local dry zone, bounded by a cone of high-speed water jet discharged from a concentric annular outlet. Preliminary tests were performed to optimize the nozzle shape and operating conditions. The resulting nozzle was used with a 5 kW CO laser for actual underwater cutting tests on stainless steel plates: Entirely satisfactory cutting performance was confirmed on various workpiece geometries and working positions. (author).

Linking carbon and hydrologic fluxes in the critical zone: Observations from high-frequency monitoring of a weathered bedrock vadose zone

Science.gov (United States)

Tune, A. K.; Druhan, J. L.; Wang, J.; Cargill, S.; Murphy, C.; Rempe, D. M.

2017-12-01

A principle challenge in quantifying feedbacks between continental weathering and atmospheric CO2 is to improve understanding of how biogeochemical processes in the critical zone influence the distribution and mobility of organic and inorganic carbon. In particular, in landscapes characterized by thin soils and heterogeneous weathered and fractured bedrock, little data exist to inform and constrain predictive models for carbon dynamics. Here, we present the results of an intensive water and gas sampling campaign across an 18 m thick, variably saturated argillite weathering profile in the Eel River CZO. We monitor water content in situ and regularly collect samples of freely-draining water, tightly-held water, and gas through wet and dry seasons using a novel Vadose-zone Monitoring System (VMS) consisting of sensors and samplers distributed across a 20 m long inclined borehole. This novel approach facilitates the interception of gas and water during transport across the entire variably saturated weathering profile. The data demonstrate that seasonal changes in saturation control the vertical distribution and mobility of carbon in the fractured critical zone. Concentrations of gaseous CO2, O2, and dissolved organic and inorganic carbon fluctuate significantly and repeatably with seasonal additions of water infiltrating the weathered bedrock. A persistent vertical structure in the concentrations of dissolved phases and gas concentrations broadly corresponds to depths associated with unsaturated, seasonally saturated, and chronically saturated zones. Associated variations in the vertical structure of mineralogy and elemental composition, including solid phase organic carbon content, are observed in core obtained during drilling. Together, our observations indicate significant respiration of organic carbon at depths greater than the base of the soil, and thus motivate further investigation of the role of heterogeneous weathered, bedrock environments, which are needed to

Giving perspective to cliff exposures with ground penetrating radar: Devonian lacustrine shore zone architecture

Science.gov (United States)

Andrews, Steven; Moreau, Julien; Archer, Stuart

2015-04-01

The orbitally-controlled cyclic lacustrine successions of the Middle Devonian in Northern Scotland contains repeated developments of shore zone sandstones. However, due to the cliff-forming nature of the succession and the attitude of the sections through these sandstones, interpretation of this facies has been problematic. To better understand the shore zone systems, we carried out very high resolution sedimentary logging and constructed photo-panels which were combined with high resolution GPR profiling (250 MHz). To ensure close ties between the sedimentary logs and the GPR data, the cliffs were accessed using rope access techniques while GPR grids were shot directly above. The profiles were shot mainly in the strike direction of what was thought to be the shore elongation every 5-10 m and every 20-30 m in the dip direction. Shore zone systems of 3 different sequences have been imaged for a total of 1155 m of GPR profile collected. This configuration has allowed 3D visualisation of the architecture of the shore zone systems and, in combination with detailed sedimentology, provided insights into the generation of the dynamic shore zone environments. The coastal cliffs of northern Scotland expose sedimentary cycles on average 16-m-thick which record deep lake, perennial lake and playa environments. The shore zone deposits reach 2 to 3.5 m in thickness. Loading and discrete channel forms are recognised in both the GPR data and sedimentary logs through the lower portion of the lake shore zone successions. Up-section the sandstone beds appear to become amalgamated forming subtle low angle accretionary bar complexes which although visible in outcrop, after careful investigation, can be fully visualised and examined in the GPR data. The 3D visualisation allowed mapping the architecture and distribution of the bars . The orientation of these features, recognised from the survey, is consistent with extensive palaeocurrent measurements from oscillation ripples. Further

Chemical zoning and homogenization of olivines in ordinary chondrites and implications for thermal histories of chondrules

Science.gov (United States)

Miyamoto, Masamichi; Mckay, David S.; Mckay, Gordon A.; Duke, Michael B.

1986-01-01

The extent and degree of homogenization of chemical zoning of olivines in type 3 ordinary chondrites is studied in order to obtain some constraints on cooling histories of chondrites. Based on Mg-Fe and CaO zoning, olivines in type 3 chondrites are classified into four types. A single chondrule usually contains olivines with the same type of zoning. Microporphyritic olivines show all four zoning types. Barred olivines usually show almost homogenized chemical zoning. The cooling rates or burial depths needed to homogenize the chemical zoning are calculated by solving the diffusion equation, using the zoning profiles as an initial condition. Mg-Fe zoning of olivine may be altered during initial cooling, whereas CaO zoning is hardly changed. Barred olivines may be homogenized during initial cooling because their size is relatively small. To simulated microporphyritic olivine chondrules, cooling from just below the liquidus at moderately high rates is preferable to cooling from above the liquidus at low rates. For postaccumulation metamorphism of type 3 chondrites to keep Mg-Fe zoning unaltered, the maximum metamorphic temperature must be less than about 400 C if cooling rates based on Fe-Ni data are assumed. Calculated cooling rates for both Fa and CaO homogenization are consistent with those by Fe-Ni data for type 4 chondrites. A hot ejecta blanket several tens of meters thick on the surface of a parent body is sufficient to homogenize Mg-Fe zoning if the temperature of the blanket is 600-700 C. Burial depths for petrologic types of ordinary chondrites in a parent body heated by Al-26 are broadly consistent with those previously proposed.

Spatial Patterns between Regolith Thickness and Forest Productivity in the Southern Sierra CZO

Science.gov (United States)

Ferrell, R. M.; Ferrell, D. F.; Hartsough, P. C.; O'Geen, T. T.

2015-12-01

Soil in conjunction with underlying weathered bedrock make up what is referred to as regolith, which can be thought of as the substrate that actively contributes water and nutrients to above ground biomass. As a result, regolith thickness is an important regulating factor of forest health and drought tolerance in the Sierra Nevada. Our project examined the relationships between landscape position, regolith thickness, and tree productivity within a sub watershed of the Southern Sierra Critical Zone Observatory. We hypothesized that tree productivity will increase with increasing regolith thickness. Data was collected in the summer of 2015 at sixty-five sites within a 522-ha watershed averaging 1180m in elevation with a MAP of 80cm and a MAT of 11C. Sites were randomly selected from a grid and then stratified in the field to capture representative samples from different landscape positions. Regolith was sampled using a hand auger with attachable extensions. At each site we augered to hard bedrock or a maximum depth of 7.56 m, which ever was shallower. Biomass measurements were made for all conifer species (DBH>20cm) within a 10m radius of the primary auger hole. Tree age was measured from a representative tree for all species in the plots. Preliminary findings suggest that there is a weak correlation between landscape position/slope and regolith thickness, likely due to differences in lithology. It also appears that terrain shape can result in conflicting outcomes: 1. It can focus water to promote physical and chemical weathering and thick regolith; or, 2. water focusing can result in landscape scouring, removing soil and weathered bedrock to create shallow regolith. Productivity appears to be a function of regolith thickness, effective precipitation and landscape position. Water collecting areas in the lower watershed are shallow to bedrock, but typically receive high amounts of effective precipitation resulting in greater tree productivity. Moreover, thick regolith

Increased supraspinatus tendon thickness following fatigue loading in rotator cuff tendinopathy: potential implications for exercise therapy.

Science.gov (United States)

McCreesh, Karen M; Purtill, Helen; Donnelly, Alan E; Lewis, Jeremy S

2017-01-01

Exercise imparts a load on tendon tissue that leads to changes in tendon properties. Studies suggest that loading immediately reduces tendon thickness, with a loss of this response in symptomatic tendinopathy. No studies investigating the response of tendon dimensions to load for the rotator cuff tendons exist. This study aimed to examine the short-term effect of loading on the thickness of the supraspinatus tendon and acromiohumeral distance those with and without rotator cuff tendinopathy. Participants were 20 painfree controls, and 23 people with painful rotator cuff tendinopathy. Supraspinatus tendon thickness and acromiohumeral distance were measured using ultrasound scans before, and at three time points after loading (1, 6 and 24 hours). Loading involved isokinetic eccentric and concentric external rotation and abduction. There was a significant increase in supraspinatus tendon thickness in the pain group at 1 (7%, ∆=0.38, 95% CI 0.19 to 0.57) and 6 hours (11%, ∆=0.53, 95% CI 0.34 to 0.71), although only the 6 hours difference exceeded minimal detectable difference. In contrast, there was a small non-significant reduction in thickness in controls. The acromiohumeral distance reduced significantly in both groups at 1 hour (controls: ∆=0.64, 95% CI 0.38 to 0.90; pain: ∆=1.1, 95% CI 0.85 to 1.33), with a larger change from baseline in the pain group. Those diagnosed with painful supraspinatus tendinopathy demonstrated increased thickening with delayed return to baseline following loading. Rehabilitation professionals may need to take into account the impact of loading to fatigue when planning rehabilitation programmes.

Surface modification of an aluminum alloy by electron beam introducing TiCN nanoparticles

Science.gov (United States)

Kolev, M.; Dimitrova, R.; Parshorov, St.; Valkov, St.; Lazarova, R.; Petrov, P.

2018-03-01

TiCN nanopowder deposited in an appropriate way on the surface of an AlSi12Cu2NiMg substrate was incorporated in the matrix using an electron beam technology. The samples were studied by means of light microscopy, SEM, and EDX; their microhardness was also determined. The formation was found of a uniform and dense coating with a thickness of 7 – 10 μgm with a good adherence to the substrate. A modified zone appeared under the coating with a thickness of 100 – 150 μgm containing dendrites of an α-solid solution and a fine eutectic between them, as well as primary silicon crystals. The microhardness of this modified zone was up to 2.4 times higher than that of the matrix. The results of SEM and EDX studies revealed unambiguously the presence of titanium in the coating and in the zones below it. Obviously, the electron beam treatment resulted in the TiCN nanoparticles penetrating into the coating and the substrate immediately below the coating.

A new subdivision of the central Sesia Zone (Aosta Valley, Italy)

Science.gov (United States)

Giuntoli, Francesco; Engi, Martin; Manzotti, Paola; Ballèvre, Michel

2015-04-01

The Sesia Zone in the Western Alps is a continental terrane probably derived from the NW-Adriatic margin and polydeformed at HP conditions during Alpine convergence. Subdivisions of the Sesia Zone classically have been based on the dominant lithotypes: Eclogitic Micaschist Complex, Seconda Zona Diorito-Kinzigitica, and Gneiss Minuti Complex. However, recent work (Regis et al., 2014) on what was considered a single internal unit has revealed that it comprises two or more tectonic slices that experienced substantially different PTDt-evolutions. Therefore, detailed regional petrographic and structural mapping (1:3k to 1:10k) was undertaken and combined with extensive sampling for petrochronological analysis. Results allow us to propose a first tectonic scheme for the Sesia Zone between the Aosta Valley and Val d'Ayas. A set of field criteria was developed and applied, aiming to recognize and delimit the first order tectonic units in this complex structural and metamorphic context. The approach rests on three criteria used in the field: (1) Discontinuously visible metasedimentary trails (mostly carbonates) considered to be monocyclic (Permo-Mesozoic protoliths); (2) mappable high-strain zones; and (3) visible differences in the metamorphic imprint. None of these key features used are sufficient by themselves, but in combination they allow us to propose a new map that delimits main units. We propose an Internal Complex with three eclogitic sheets, each 0.5-3 km thick. Dominant lithotypes include micaschists associated with mafic rocks and minor orthogneiss. The main foliation is of HP, dipping moderately NW. Each of these sheets is bounded by (most likely monometamorphic) sediments, <10-50 m thick. HP-relics (of eclogite facies) are widespread, but a greenschist facies overprint locally is strong close to the tectonic contact to neighbouring sheets. An Intermediate Complex lies NW of the Internal Complex and comprises two thinner, wedge-shaped units termed slices. These

Radiation protection zoning

International Nuclear Information System (INIS)

2015-01-01

Radiation being not visible, the zoning of an area containing radioactive sources is important in terms of safety. Concerning radiation protection, 2 work zones are defined by regulations: the monitored zone and the controlled zone. The ministerial order of 15 may 2006 settles the frontier between the 2 zones in terms of radiation dose rates, the rules for access and the safety standards in both zones. Radioprotection rules and the name of the person responsible for radiation protection must be displayed. The frontier between the 2 zones must be materialized and marked with adequate equipment (specific danger signs and tapes). Both zones are submitted to selective entrance, the access for the controlled zone is limited because of the radiation risk and of the necessity of confining radioactive contamination while the limitation of the access to the monitored zone is due to radiation risk only. (A.C.)

Space-time evolution of cataclasis in carbonate fault zones

Science.gov (United States)

Ferraro, Francesco; Grieco, Donato Stefano; Agosta, Fabrizio; Prosser, Giacomo

2018-05-01

The present contribution focuses on the micro-mechanisms associated to cataclasis of both calcite- and dolomite-rich fault rocks. This work combines field and laboratory data of carbonate fault cores currently exposed in central and southern Italy. By first deciphering the main fault rock textures, their spatial distribution, crosscutting relationships and multi-scale dimensional properties, the relative timing of Intragranular Extensional Fracturing (IEF), chipping, and localized shear is inferred. IEF was predominant within already fractured carbonates, forming coarse and angular rock fragments, and likely lasted for a longer period within the dolomitic fault rocks. Chipping occurred in both lithologies, and was activated by grain rolling forming minute, sub-rounded survivor grains embedded in a powder-like carbonate matrix. The largest fault zones, which crosscut either limestones or dolostones, were subjected to localized shear and, eventually, to flash temperature increase which caused thermal decomposition of calcite within narrow (cm-thick) slip zones. Results are organized in a synoptic panel including the main dimensional properties of survivor grains. Finally, a conceptual model of the time-dependent evolution of cataclastic deformation in carbonate rocks is proposed.

Studies on mechanical properties, microstructure and fracture morphology details of laser beam welded thick SS304L plates for fusion reactor applications

Energy Technology Data Exchange (ETDEWEB)

Buddu, Ramesh Kumar, E-mail: buddu@ipr.res.in [Fusion Reactor Materials Development and Characterization Division, Institute for Plasma Research, Bhat, Gandhinagar 382428 (India); Chauhan, N.; Raole, P.M. [Fusion Reactor Materials Development and Characterization Division, Institute for Plasma Research, Bhat, Gandhinagar 382428 (India); Natu, Harshad [Magod Laser Machining Pvt. Ltd, Jigani, Bengaluru 560105 (India)

2015-06-15

Highlights: • CO{sub 2} laser welding of 8 mm thick SS304L plates has been carried out and full penetration welds fabricated and characterized for mechanical properties and microstructure details. • Welded samples have shown tensile properties comparable to base indicating good weld quality joints. • Impact fracture tests of weld zone and heat affected zone samples have shown poor toughness compared to the base metal. • SEM analysis of fracture samples of tensile and impact specimens indicated the complex microstructure features in weld zone and combined ductile and brittle fracture features. • Combined features of dendrite and cellular structures are observed in weld microstructures with narrow HAZ and delta ferrite is found in the welds and further confirmed by higher Ferrite Number data. - Abstract: Austenitic stainless steel is widely used structural material for the fabrication of the fusion reactor components. Laser welding is high power density process which offers several advantages over the other conventional processes like Tungsten Inert Gas welding. The features like low distortion, narrow heat affected zone, deep penetration in single pass, good mechanical properties are some of the advantages of laser welding process. The laser weld process parameters optimization has several challenges in terms of overcoming the weld defects like voids due to lack of penetration over depth, undercuts and porosity. The present paper reports the studies carried out with CO{sub 2} laser welding of 8 mm thick austenitic stainless steel SS304L plates and their characterization of mechanical properties, microstructure and fracture morphology details. The weld process parameter optimization towards defect free welds with full penetration welding has been carried out. The welded samples have shown tensile properties comparable to base metal, bend tests are successfully passed. The hardness measurements have shown slightly higher for weld zone compared to base metal

Studies on mechanical properties, microstructure and fracture morphology details of laser beam welded thick SS304L plates for fusion reactor applications

International Nuclear Information System (INIS)

Buddu, Ramesh Kumar; Chauhan, N.; Raole, P.M.; Natu, Harshad

2015-01-01

Highlights: • CO 2 laser welding of 8 mm thick SS304L plates has been carried out and full penetration welds fabricated and characterized for mechanical properties and microstructure details. • Welded samples have shown tensile properties comparable to base indicating good weld quality joints. • Impact fracture tests of weld zone and heat affected zone samples have shown poor toughness compared to the base metal. • SEM analysis of fracture samples of tensile and impact specimens indicated the complex microstructure features in weld zone and combined ductile and brittle fracture features. • Combined features of dendrite and cellular structures are observed in weld microstructures with narrow HAZ and delta ferrite is found in the welds and further confirmed by higher Ferrite Number data. - Abstract: Austenitic stainless steel is widely used structural material for the fabrication of the fusion reactor components. Laser welding is high power density process which offers several advantages over the other conventional processes like Tungsten Inert Gas welding. The features like low distortion, narrow heat affected zone, deep penetration in single pass, good mechanical properties are some of the advantages of laser welding process. The laser weld process parameters optimization has several challenges in terms of overcoming the weld defects like voids due to lack of penetration over depth, undercuts and porosity. The present paper reports the studies carried out with CO 2 laser welding of 8 mm thick austenitic stainless steel SS304L plates and their characterization of mechanical properties, microstructure and fracture morphology details. The weld process parameter optimization towards defect free welds with full penetration welding has been carried out. The welded samples have shown tensile properties comparable to base metal, bend tests are successfully passed. The hardness measurements have shown slightly higher for weld zone compared to base metal and the

Aftershocks illuminate the 2011 Mineral, Virginia, earthquake causative fault zone and nearby active faults

Science.gov (United States)

Horton, J. Wright; Shah, Anjana K.; McNamara, Daniel E.; Snyder, Stephen L.; Carter, Aina M

2015-01-01

Deployment of temporary seismic stations after the 2011 Mineral, Virginia (USA), earthquake produced a well-recorded aftershock sequence. The majority of aftershocks are in a tabular cluster that delineates the previously unknown Quail fault zone. Quail fault zone aftershocks range from ~3 to 8 km in depth and are in a 1-km-thick zone striking ~036° and dipping ~50°SE, consistent with a 028°, 50°SE main-shock nodal plane having mostly reverse slip. This cluster extends ~10 km along strike. The Quail fault zone projects to the surface in gneiss of the Ordovician Chopawamsic Formation just southeast of the Ordovician–Silurian Ellisville Granodiorite pluton tail. The following three clusters of shallow (<3 km) aftershocks illuminate other faults. (1) An elongate cluster of early aftershocks, ~10 km east of the Quail fault zone, extends 8 km from Fredericks Hall, strikes ~035°–039°, and appears to be roughly vertical. The Fredericks Hall fault may be a strand or splay of the older Lakeside fault zone, which to the south spans a width of several kilometers. (2) A cluster of later aftershocks ~3 km northeast of Cuckoo delineates a fault near the eastern contact of the Ordovician Quantico Formation. (3) An elongate cluster of late aftershocks ~1 km northwest of the Quail fault zone aftershock cluster delineates the northwest fault (described herein), which is temporally distinct, dips more steeply, and has a more northeastward strike. Some aftershock-illuminated faults coincide with preexisting units or structures evident from radiometric anomalies, suggesting tectonic inheritance or reactivation.

Residual stress measurements in thick structural weldments by means of neutron diffraction

International Nuclear Information System (INIS)

Ohms, C.; Youtsos, A.G.; Idsert, P. v.d.; Timke, T.

2000-01-01

Welding residual stresses in large structural components are a major concern with respect to their performance and lifetime. In large structures reasonable thermal stress relief treatment is usually impossible due to the component size. On the other hand, prediction of welding stresses by numerical modelling has not yet proven to be generally reliable, while the experimental determination of such stresses remains a demanding task. At the high flux reactor (HFR), Petten, a new residual stress diffractometer has been installed recently capable of handling of components up to 1000 kg - the large component neutron diffraction facility (LCNDF). It has facilitated residual stress measurements in two large welded components, of which results are presented here. The first component represents a bi-metallic weld in form of a pipe of 25 mm wall thickness. Three dimensional measurements of residual stress are discussed in detail. The second specimen is a 66 mm wall thickness austenitic steel nuclear piping weld. Results on relief of strain within the weld through post weld heat treatment (PWHT) are presented. Additionally results obtained earlier at former CRNL (CAN) on a section of a thick nuclear piping weld are presented in order to illustrate the variation in the reference lattice parameter trough the weld and the heat affected zone (HAZ). These results clearly show the necessity to determine the reference parameters for each location in all measurement directions by means of measurements in small coupons free of macro-stresses. (orig.)

Pitting corrosion of friction stir welded aluminum alloy thick plate in alkaline chloride solution

International Nuclear Information System (INIS)

Xu Weifeng; Liu Jinhe; Zhu Hongqiang

2010-01-01

The pitting corrosion of different positions (Top, Middle and Bottom) of weld nugget zone (WNZ) along thickness plate in friction stir welded 2219-O aluminum alloy in alkaline chloride solution was investigated by using open circuit potential, cyclic polarization, scanning electron microscopy and atomic force microscope. The results indicate that the material presents significant passivation, the top has highest corrosion potential, pitting potential and re-passivation potential compared with the bottom and base material. With the increase of traverse speed from 60 to 100 mm/min or rotary speed from 500 to 600 rpm, the corrosion resistance decreases.

Insights upon upper crustal arhitecture of a subduction zone and its surroundings - Vrancea Zone and Focsani Basin - substantiated by geophysical studies

Science.gov (United States)

Bocin, A.; Stephenson, R.; Mocanu, V.

2007-12-01

The DACIA PLAN (Danube and Carpathian Integrated Action on Processes in the Lithosphere and Neotectonics) deep seismic reflection survey was performed in August-September 2001, with the proposed objective of obtaining new information on the deep structure of the external Carpathians nappes and the architecture of Tertiary/Quaternary basin developed within and adjacent to the Vrancea zone, including the rapidly subsiding Focsani Basin. The DACIA-PLAN profile is about 140 km long, having a roughly NW-SE direction, from near the southeast Transylvanian Basin, across the mountainous southeastern Carpathians and their foreland to near the Danube River. A high resolution 2.5D velocity model of the upper crust along the seismic profile has been determined from a tomographic inversion and a 2D ray tracing forward modelling of the DACIA PLAN first arrival data. Peculiar shallow high velocities indicate that pre-Tertiary basement in the Vrancea Zone (characterised by velocities greater than 5.6 km/s) is involved in Carpathian thrusting while rapid alternance, vertically or horizontally, of velocity together with narrowingly contemporary crustal events suggests uplifting. Further to the east, at the foreland basin-thrust belt transition zone (well defined within velocity values), the velocity model suggests a nose of the Miocene Subcarpathians nappe being underlain by Focsani Basin units. A Miocene and younger Focsani Basin sedimentary succession of ~10 km thickness is ascertained by a gradual increase of velocities and strongly defined velocity boundaries.

29 CFR 780.308 - Definition of immediate family.

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Definition of immediate family. 780.308 Section 780.308... 13(a)(6) Statutory Provisions § 780.308 Definition of immediate family. The Act does not define the scope of “immediate family.” Whether an individual other than a parent, spouse or child will be...

Autonomous Sea-Ice Thickness Survey

Science.gov (United States)

2016-06-01

the conductivity of an infinitely thick slab of sea ice. Ice thickness, Hice, is then obtained by subtracting the height of the ...Thickness Survey of Sea Ice Runway” ERDC/CRREL SR-16-4 ii Abstract We conducted an autonomous survey of sea -ice thickness using the Polar rover Yeti...efficiency relative to manual surveys routinely con- ducted to assess the safety of roads and runways constructed on the sea ice. Yeti executed the

Spatial variations of effective elastic thickness of the Lithosphere in the Southeast Asia regions

Science.gov (United States)

Shi, Xiaobin; Kirby, Jon; Yu, Chuanhai; Swain, Chris; Zhao, Junfeng

2016-04-01

The effective elastic thickness Te corresponds to the thickness of an idealized elastic beam that would bend similarly to the actual lithosphere under the same applied loads, and could provide important insight into rheology and state of stress. Thus, it is helpful to improve our understanding of the relationship between tectonic styles, distribution of earthquakes and lithospheric rheology in various tectonic settings. The Southeast Asia, located in the southeastern part of the Eurasian Plate, comprises a complex collage of continental fragments, volcanic arcs, and suture zones and marginal oceanic basins, and is surrounded by tectonically active margins which exhibit intense seismicity and volcanism. The Cenozoic southeastward extrusion of the rigid Indochina Block due to the Indo-Asian collision resulted in the drastic surface deformation in the western area. Therefore, a high resolution spatial variation map of Te might be a useful tool for the complex Southeast Asia area to examine the relationships between surface deformation, earthquakes, lithospheric structure and mantle dynamics. In this study, we present a high-resolution map of spatial variations of Te in the Southeast Asia area using the wavelet method, which convolves a range of scaled wavelets with the two data sets of Bouguer gravity anomaly and topography. The topography and bathymetry grid data was extracted from the GEBCO_08 Grid of GEBCO digital atlas. The pattern of Te variations agrees well with the tectonic provinces in the study area. On the whole, low lithosphere strength characterizes the oceanic basins, such as the South China Sea, the Banda sea area, the Celebes Sea, the Sulu Sea and the Andaman Sea. Unlike the oceanic basins, the continental fragments show a complex pattern of Te variations. The Khorat plateau and its adjacent area show strong lithosphere characteristics with a Te range of 20-50 km, suggesting that the Khorat plateau is the strong core of the Indochina Block. The West

Thickness evaluation using a new relationship between film density and penetrated thickness in radiography

International Nuclear Information System (INIS)

Lee, Sung Sik; Kim, Young H.

2005-01-01

In order to improve the accuracies in the thickness evaluation using radiography, a new relationship between film density and penetrated thickness has been proposed, and experimental verification of the proposed relationship was carried out by using the X- and γ-ray radiographs of two carbon steel step wedges. A new parameter, the logarithmic gradient of film density, was defined in order to express the characteristics of the radiographic film for wider range of film density. A new relationship between the film density and the penetrated thickness were formulated using the logarithmic gradient of the film density. In experiment, the logarithmic gradient of the film density was independent on both the exposure and the film density and measured for the radiographic film used in the present work from the slope of the fitting lines for the same penetrated thickness. Experimental results verifies the accuracy of the proposed relationship between film density and the penetrated thickness for the range of film density from 1.0 to 3.5. The thickness can be more accurately determined by using the proposed relationship and the parameters determined by experiment. It is also found that the γ-ray having simple energy spectrum is more appropriate radiation source for the evaluation of the thickness from the film density of the radiograph

Geophysical and geochemical constraints on the geodynamic origin of the Vrancea Seismogenic Zone Romania

Science.gov (United States)

Fillerup, Melvin A.

The Vrancea Seismogenic Zone (VSZ) of Romania is a steeply NW-dipping volume (30 x 70 x 200 km) of intermediate-depth seismicity in the upper mantle beneath the bend zone of the Eastern Carpathians. The majority of tectonic models lean heavily on subduction processes to explain the Vrancea mantle seismicity and the presence of a Miocene age calc-alkaline volcanic arc in the East Carpathian hinterland. However, recent deep seismic reflection data collected over the Eastern Carpathian bend zone image an orogen lacking (1) a crustal root and (2) dipping crustal-scale fabrics routinely imaged in modern and ancient subduction zones. The DRACULA I and DACIA-PLAN deep seismic reflection profiles show that the East Carpathian orogen is supported by crust only 30-33 km thick while the Focsani basin (foreland) and Transylvanian basin (hinterland) crust is 42 km and 46 km thick respectively. Here the VSZ is interpreted as the former Eastern Carpathian orogenic root which was removed as a result of continental lithospheric delamination and is seismically foundering beneath the East Carpathian bend zone. Because large volumes of calc-alkaline volcanism are typically associated with subduction settings existing geochemical analyses from the Calimani, Gurghiu, and Harghita Mountains (CGH) have been reinterpreted in light of the seismic data which does not advocate the subduction of oceanic lithosphere. CGH rocks exhibit a compositional range from basalt to rhyolite, many with high-Mg# (Mg/Mg+Fe > 0.60), high-Sr (>1000 ppm), and elevated delta-O18 values (6-8.7 /) typical of arc lavas, and are consistent with mixing of mantle-derived melts with a crustal component. The 143Nd/144Nd (0.5123-0.5129) and 87Sr/86Sr (0.7040-0.7103) ratios similarly suggest mixing of mantle and crustal end members to obtain the observed isotopic compositions. A new geochemical model is presented whereby delamination initiates a geodynamic process like subduction but with the distinct absence of subducted

Perivenous and perisinusoidal collagen content in the acinar zone 3 in the "normal" liver. A light microscopical study

DEFF Research Database (Denmark)

Junge, Jette; Vyberg, M; Horn, T

1988-01-01

The thickness of the terminal hepatic vein wall (TTHV) and the content of perisinusoidal collagen in 989 zone 3 areas in Picro-Sirius-stained sections from 117 liver biopsies with normal morphology or slight non-specific changes were analyzed. TTHV varied from 0.4 micron to 21.3 microns (median 3.......8 microns). A positive correlation was found between TTHV and the diameter of the terminal hepatic vein. The average TTHV of the individual biopsies was not correlated to age, sex or liver morphology. The average zone 3 collagen content did not exceed that of zones 2 and 1, with the exception of biopsies...... with slight steatosis, where a minimal increase in zone 3 collagen was found. The normal variability of TTHV and the correlation to the diameter of THV must be considered in the evaluation of perivenular fibrosis. Even a slight increase in perisinusoidal collagen content may be suggestive of a pathological...

Nitrogen fluxes through unsaturated zones in five agricultural settings across the United States

Science.gov (United States)

Green, C.T.; Fisher, L.H.; Bekins, B.A.

2008-01-01

The main physical and chemical controls on nitrogen (N) fluxes between the root zone and the water table were determined for agricultural sites in California, Indiana, Maryland, Nebraska, and Washington from 2004 to 2005. Sites included irrigated and nonirrigated fields; soil textures ranging from clay to sand; crops including corn, soybeans, almonds, and pasture; and unsaturated zone thicknesses ranging from 1 to 22 m. Chemical analyses of water from lysimeters and shallow wells indicate that advective transport of nitrate is the dominant process affecting the flux of N below the root zone. Vertical profiles of (i) nitrogen species, (ii) stable isotopes of nitrogen and oxygen, and (iii) oxygen, N, and argon in unsaturated zone air and correlations between N and other agricultural chemicals indicate that reactions do not greatly affect N concentrations between the root zone and the capillary fringe. As a result, physical factors, such as N application rate, water inputs, and evapotranspiration, control the differences in concentrations among the sites. Concentrations of N in shallow lysimeters exhibit seasonal variation, whereas concentrations in lysimeters deeper than a few meters are relatively stable. Based on concentration and recharge estimates, fluxes of N through the deep unsaturated zone range from 7 to 99 kg ha-1 yr-1. Vertical fluxes of N in ground water are lower due to spatial and historical changes in N inputs. High N fluxes are associated with coarse sediments and high N application rates. Copyright ?? 2008 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.

Immediate loading versus immediate provisionalization of maxillary single-tooth replacements: a prospective randomized study with BioComp implants

NARCIS (Netherlands)

Lindeboom, Jerome A.; Frenken, Joost W.; Dubois, Leander; Frank, Michael; Abbink, Ingmar; Kroon, Frans H.

2006-01-01

PURPOSE: The aim of this prospective randomized study was to evaluate the clinical outcome of immediately loaded solid plasma sprayed (TPS) BioComp (BioComp Industries BV, Vught, The Netherlands) implants versus immediate provisionalized but non-loaded BioComp implants in the anterior and premolar

[Performance dependence of organic light-emitting devices on the thickness of Alq3 emitting layer].

Science.gov (United States)

Lian, Jia-rong; Liao, Qiao-sheng; Yang, Rui-bo; Zheng, Wei; Zeng, Peng-ju

2010-10-01

The dependence of opto-electronical characteristics in organic light-emitting devices on the thickness of Alq3 emitter layer was studied, where MoO3, NPB, and Alq3 were used as hole injector, hole transporter, and emitter/electron transporter, respectively. By increasing the thickness of Alq3 layer from 20 to 100 nm, the device current decreased gradually, and the EL spectra of devices performed a little red shift with an obvious broadening in long wavelength range but a little decrease in intensity of short wavelength range. The authors simulated the EL spectra using the photoluminescence (PL) spectra of Alq3 as Alq3 intrinsic emission, which coincided with the experimental EL spectra well. The simulated results suggested that the effect of interference takes the major role in broadening the long wavelength range of EL spectra, and the distribution of emission zone largely affects the profile of EL spectra in short wavelength range.

Diaphragmatic thickness ratio (inspiratory/expiratory) as a diagnostic method of diaphragmatic palsy associated with interescalene block.

Science.gov (United States)

López Escárraga, V M; Dubos España, K; Castillo Bustos, R H; Peidró, L; Sastre, S; Sala-Blanch, X

2018-02-01

Diaphragmatic paralysis is a side-effect associated with interscalene block. Thickness index of the diaphragm muscle (inspiratory thickness/expiratory thickness) obtained by ultrasound has recently been introduced in clinical practice for diagnosis of diaphragm muscle atrophy. Our objective was to evaluate this index for the diagnosis of acute phrenic paresis associated with interscalene block. We designed an observational study in 22 patients scheduled for shoulder arthroscopy. Spirometry was performed (criteria of phrenic paresis was a decrease in FVC and FEV1 ≥20%). Ultrasound apposition zone was assessed in anterior axillary line and diaphragmatic displacement was evaluated on inspiration and expiration (number of intercostal spaces; phrenic paresis considered a reduction ≥25%) and thickness of the diaphragm muscle (a phrenic paresis was considered an index block at C5-C6 with 20ml of 0.5% ropivacaine. Twenty-one patients (95%) presented phrenic nerve block according to one or more of the methods used. One patient did not show any symptoms or signs suggestive of phrenic paralysis and was excluded. All the patients presented phrenic paresis based on the diaphragmatic thickness index, with the pre-block index being 1.8±0.5 and post-block of 1.05±0.06 (Pblock (from 1.9±0.5 intercostal spaces to 0.5±0.3; Pblock. This index does not require a baseline pre-assessment. Copyright © 2017 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

Influence of thickness of zinc coating on CMT welding-brazing with AlSi5 alloy wire

Science.gov (United States)

Jin, Pengli; Wang, Zhiping; Yang, Sinan; Jia, Peng

2018-03-01

Effect of thickness of zinc coating on Cold Mattel Transfer (CMT) brazing of aluminum and galvanized steel is investigated. The thickness of zinc coating is 10 μm, 30 μm, and 60 μm, respectively. A high-speed camera was used to capture images of welding process of different specimens; the microstructure and composition analyses of the welding seam were examined by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS); the mechanical properties were measured in the form of Nano-indentation experiments. The results showed that arc characteristics and metal transfer behavior were unsteady at the beginning of welding process and that became stable after two cycles of CMT. With the thickness of zinc coating thickening, arc characteristics and metal transfer behaviors were more deteriorated. Compared with 10 μm and 30 μm, clad appearance of 60 μm was straight seam edges and a smooth surface which wetting angle was 60°. Zinc-rich zone at the seam edges was formed by zinc dissolution and motel pool oscillating, and zinc content of 10 μm and 30 μm were 5.8% and 7.75%. Zinc content of 60 μm was 14.61%, and it was a belt between galvanized steel and welding seam. The thickness of intermetallic compounds layer was in the range of 1-8 μm, and it changed with the thickness of zinc coating. The average hardness of the reaction layer of 60 μm is 9.197 GPa.

Radiofrequency ablation of rabbit liver in vivo: effect of the Pringle maneuver on pathologic changes in liver surrounding the ablation zone

International Nuclear Information System (INIS)

Kim, Seung Kwon; Lim, Hyo K; Ryu, Jeong Ah

2004-01-01

We wished to evaluate the effect of the Pringle maneuver (occlusion of both the hepatic artery and portal vein) on the pathologic changes in the hepatic vessels, bile ducts and liver parenchyma surrounding the ablation zone in rabbit livers. Radiofrequency (RF) ablation zones were created in the livers of 24 rabbits in vivo by using a 50-W, 480-kHz monopolar RF generator and a 15-gauge expandable electrode with four sharp prongs for 7 mins. The tips of the electrodes were placed in the liver parenchyma near the porta hepatis with the distal 1 cm of their prongs deployed. Radiofrequency ablation was performed in the groups with (n=12 rabbits) and without (n=12 rabbits) the Pringle maneuver. Three animals of each group were sacrificed immediately, three days (the acute phase), seven days (the early subacute phase) and two weeks (the late subacute phase) after RF ablation. The ablation zones were excised and serial pathologic changes in the hepatic vessels, bile ducts and liver parenchyma surrounding the ablation zone were evaluated. With the Pringle maneuver, portal vein thrombosis was found in three cases (in the immediate [n=2] and acute phase [n=1]), bile duct dilatation adjacent to the ablation zone was found in one case (in the late subacute phase [n=1]), infarction adjacent to the ablation zone was found in three cases (in the early subacute [n=2] and late subacute [n=1] phases). None of the above changes was found in the livers ablated without the Pringle maneuver. On the microscopic findings, centrilobular congestion, sinusoidal congestion, sinusoidal platelet and neutrophilic adhesion, and hepatocyte vacuolar and ballooning changes in liver ablated with Pringle maneuver showed more significant changes than in those livers ablated without the Pringle maneuver (ρ < 0.05). Radiofrequency ablation with the Pringle maneuver created more severe pathologic changes in the portal vein, bile ducts and liver parenchyma surrounding the ablation zone compared with RF

Mapping of groundwater potential zones in Salem Chalk Hills, Tamil Nadu, India, using remote sensing and GIS techniques.

Science.gov (United States)

Thilagavathi, N; Subramani, T; Suresh, M; Karunanidhi, D

2015-04-01

This study proposes to introduce the remote sensing and geographic information system (GIS) techniques in mapping the groundwater potential zones. Remote sensing and GIS techniques have been used to map the groundwater potential zones in Salem Chalk Hills, Tamil Nadu, India. Charnockites and fissile hornblende biotite gneiss are the major rock types in this region. Dunites and peridodites are the ultramafic rocks which cut across the foliation planes of the gneisses and are highly weathered. It comprises magnesite and chromite deposits which are excavated by five mining companies by adopting bench mining. The thickness of weathered and fracture zone varies from 2.2 to 50 m in gneissic formation and 5.8 to 55 m in charnockite. At the contacts of gneiss and charnockite, the thickness ranges from 9.0 to 90.8 m favoring good groundwater potential. The mine lease area is underlined by fractured and sheared hornblende biotite gneiss where groundwater potential is good. Water catchment tanks in this area of 5 km radius are small to moderate in size and are only seasonal. They remain dry during summer seasons. As perennial water resources are remote, the domestic and agricultural activities in this region depend mainly upon the groundwater resources. The mines are located in gently slope area, and accumulation of water is not observed except in mine pits even during the monsoon period. Therefore, it is essential to map the groundwater potential zones for proper management of the aquifer system. Satellite imageries were also used to extract lineaments, hydrogeomorphic landforms, drainage patterns, and land use, which are the major controlling factors for the occurrence of groundwater. Various thematic layers pertaining to groundwater existence such as geology, geomorphology, land use/land cover, lineament, lineament density, drainage, drainage density, slope, and soil were generated using GIS tools. By integrating all the above thematic layers based on the ranks and

Imaging the deep structures of the convergent plates along the Ecuadorian subduction zone through receiver function analysis

Science.gov (United States)

Galve, A.; Charvis, P.; Regnier, M. M.; Font, Y.; Nocquet, J. M.; Segovia, M.

2017-12-01

The Ecuadorian subduction zone was affected by several large M>7.5 earthquakes. While we have low resolution on the 1942, 1958 earthquakes rupture zones extension, the 2016 Pedernales earthquake, that occurs at the same location than the 1942 earthquake, give strong constraints on the deep limit of the seismogenic zone. This downdip limit is caused by the onset of plasticity at a critical temperature (> 350-450 °C for crustal materials, or serpentinized mantle wedge, and eventually > 700 °C for dry mantle). However we still don't know exactly where is the upper plate Moho and therefore what controls the downdip limit of Ecuadorian large earthquakes seismogenic zone. For several years Géoazur and IG-EPN have maintained permanent and temporary networks (ADN and JUAN projects) along the margin to register the subduction zone seismological activity. Although Ecuador is not a good place to perform receiver function due to its position with respect to the worldwide teleseismic sources, the very long time deployment compensate this issue. We performed a frequency dependent receiver function analysis to derive (1) the thickness of the downgoing plate, (2) the interplate depth and (3) the upper plate Moho. These constraints give the frame to interpretation on the seismogenic zone of the 2016 Pedernales earthquake.

Fuel conditioning facility zone-to-zone transfer administrative controls

International Nuclear Information System (INIS)

Pope, C. L.

2000-01-01

The administrative controls associated with transferring containers from one criticality hazard control zone to another in the Argonne National Laboratory (ANL) Fuel Conditioning Facility (FCF) are described. FCF, located at the ANL-West site near Idaho Falls, Idaho, is used to remotely process spent sodium bonded metallic fuel for disposition. The process involves nearly forty widely varying material forms and types, over fifty specific use container types, and over thirty distinct zones where work activities occur. During 1999, over five thousand transfers from one zone to another were conducted. Limits are placed on mass, material form and type, and container types for each zone. Ml material and containers are tracked using the Mass Tracking System (MTG). The MTG uses an Oracle database and numerous applications to manage the database. The database stores information specific to the process, including material composition and mass, container identification number and mass, transfer history, and the operators involved in each transfer. The process is controlled using written procedures which specify the zone, containers, and material involved in a task. Transferring a container from one zone to another is called a zone-to-zone transfer (ZZT). ZZTs consist of four distinct phases, select, request, identify, and completion

Disentangling The Thick Concept Argument

DEFF Research Database (Denmark)

Blomberg, Olle

2007-01-01

Critics argue that non-cognitivism cannot adequately account for the existence and nature of some thick moral concepts. They use the existence of thick concepts as a lever in an argument against non-cognitivism, here called the Thick Concept Argument (TCA). While TCA is frequently invoked...

Application of Industrial XRF Coating Thickness Analyzer for Phosphate Coating Thickness on Steel

Directory of Open Access Journals (Sweden)

Aleksandr Sokolov

2018-03-01

Full Text Available The results of industrial application of an online X-ray fluorescence coating thickness analyzer for measuring the thickness of phosphate coatings on moving steel strips are considered in the article. The target range of coating thickness to be measured is from tens to hundreds of mg/m2 in a measurement time of 10 s. The measurement accuracy observed during long-duration factory acceptance test was 10–15%. The coating thickness analyzer consists of two XRF gauges, mounted above and below the steel strip and capable of moving across the moving strip system for their suspension and relocation and electronic control unit. Fully automated software was developed to automatically and continuously (24/7 control both gauges, scanning both sides of the steel strip, and develop and test methods for measuring new coatings. It allows performing offline storage and retrieval of the measurement results, remotely controlling the analyzer components and measurement modes from a control room. The developed XRF coating thickness analyzer can also be used for real-time measurement of other types of coatings, both metallic and non-metallic.

Potential field signatures along the Zagros collision zone in Iran

Science.gov (United States)

Abedi, Maysam; Fournier, Dominique; Devriese, Sarah G. R.; Oldenburg, Douglas W.

2018-01-01

The Zagros orogenic belt, known as an active fold-thrust belt, was formed in southwestern Iran due to the convergence of the Arabian and Eurasian plates. In this study, potential field data are inverted in 3D to image the variations of magnetic susceptibility and density contrast along the collision zone, resulting in better tectonic understanding of the studied region. Geophysical data measured by airborne magnetic and ground-based gravity systems are used to construct an integrated model that facilitates the interpretations of various tectonic zones across a 450-km line. This line intersects the main structural units from the SW portion of the Zagros belt. The constructed model reveals a contrast that indicates the transition between the two continental plates coinciding with the western boundaries of the Sanandaj-Sirjan Zone (SSZ) at the Main Zagros Thrust (MZT) fault. The subduction of the Arabian continental crust below the Iranian one is evident because of its lower susceptibility property and alternating sequence of high and low density regions. Higher susceptibility, magnetic remanence and density are the mainstays of the Urumieh-Dokhtar Magmatic Assemblage (UDMA) zone at the NE of the studied route, whereas lower values of these properties correspond to (1) the thin massive Tertiary-Neogene and Quaternary sediments of the central domain (CD) zone, and (2) the thick sedimentary and salt intrusion cover over the Zagros Fold-and-Thrust belt (ZFTB). Higher density of regions in the Arabian crust below the ZFTB implies that fault activities have caused significant vertical displacement of the basement. Finally, a simplified geological model is presented based upon the inversions of the geophysical data, in which the main geological units are divided along the studied route.

Molecular differences in transition zone and peripheral zone prostate tumors

Science.gov (United States)

Sinnott, Jennifer A.; Rider, Jennifer R.; Carlsson, Jessica; Gerke, Travis; Tyekucheva, Svitlana; Penney, Kathryn L.; Sesso, Howard D.; Loda, Massimo; Fall, Katja; Stampfer, Meir J.; Mucci, Lorelei A.; Pawitan, Yudi; Andersson, Sven-Olof; Andrén, Ove

2015-01-01

Prostate tumors arise primarily in the peripheral zone (PZ) of the prostate, but 20–30% arise in the transition zone (TZ). Zone of origin may have prognostic value or reflect distinct molecular subtypes; however, it can be difficult to determine in practice. Using whole-genome gene expression, we built a signature of zone using normal tissue from five individuals and found that it successfully classified nine tumors of known zone. Hypothesizing that this signature captures tumor zone of origin, we assessed its relationship with clinical factors among 369 tumors of unknown zone from radical prostatectomies (RPs) and found that tumors that molecularly resembled TZ tumors showed lower mortality (P = 0.09) that was explained by lower Gleason scores (P = 0.009). We further applied the signature to an earlier study of 88 RP and 333 transurethral resection of the prostate (TURP) tumor samples, also of unknown zone, with gene expression on ~6000 genes. We had observed previously substantial expression differences between RP and TURP specimens, and hypothesized that this might be because RPs capture primarily PZ tumors, whereas TURPs capture more TZ tumors. Our signature distinguished these two groups, with an area under the receiver operating characteristic curve of 87% (P zones. Zone of origin may be important to consider in prostate tumor biomarker research. PMID:25870172

Volatile organic compounds in the unsaturated zone from radioactive wastes

Science.gov (United States)

Baker, Ronald J.; Andraski, Brian J.; Stonestrom, David A.; Luo, Wentai

2012-01-01

Volatile organic compounds (VOCs) are often comingled with low-level radioactive wastes (LLRW), but little is known about subsurface VOC emanations from LLRW landfills. The current study systematically quantified VOCs associated with LLRW over an 11-yr period at the USGS Amargosa Desert Research Site (ADRS) in southwestern Nevada. Unsaturated-zone gas samples of VOCs were collected by adsorption on resin cartridges and analyzed by thermal desorption and GC/MS. Sixty of 87 VOC method analytes were detected in the 110-m-thick unsaturated zone surrounding a LLRW disposal facility. Chlorofluorocarbons (CFCs) were detected in 100% of samples collected. Chlorofluorocarbons are powerful greenhouse gases, deplete stratospheric ozone, and are likely released from LLRW facilities worldwide. Soil-gas samples collected from a depth of 24 m and a horizontal distance 100 m south of the nearest waste-disposal trench contained >60,000 ppbv total VOCs, including >37,000 ppbv CFCs. Extensive sampling in the shallow unsaturated zone (0–2 m deep) identified areas where total VOC concentrations exceeded 5000 ppbv at the 1.5-m depth. Volatile organic compound concentrations exceeded background levels up to 300 m from the facility. Maximum vertical diffusive fluxes of total VOCs were estimated to be 1 g m-2 yr-1. Volatile organic compound distributions were similar but not identical to those previously determined for tritium and elemental mercury. To our knowledge, this study is the first to characterize the unsaturated zone distribution of VOCs emanating from a LLRW landfill. Our results may help explain anomalous transport of radionuclides at the ADRS and elsewhere.

Structural and microstructural evolution of fault zones in Cretaceous poorly lithified sandstones of the Rio do Peixe basin, Paraiba, NE Brazil

Science.gov (United States)

Balsamo, Fabrizio; Nogueira, Francisco; Storti, Fabrizio; Bezerra, Francisco H. R.; De Carvalho, Bruno R.; André De Souza, Jorge

2017-04-01

are arranged in conjugate system consisting of NNW-SSE- and WNW-ESE-trending fault zones with left-lateral and right-lateral kinematics, respectively. Compared to extensional fault zones, strike-slip fault zones have narrow fault cores (few cm thick) and up to 2-3 m-thick damage zones. Microstructural observations indicate that cataclasis with pervasive grain size reduction is the dominant deformation mechanisms within the fault core, thus suggesting that late-stage strike-slip faulting occurred when sandstones were partially lithified by diagenetic processes. Alternatively, the change in deformation mechanisms may indicate faulting at greater depth. Structural and microstructural data suggest that fault zones in the Rio do Peixe basin developed in a progression from "ductile" (sensu Rutter, 1986) to more "brittle" deformation during changes from extensional to strike-slip kinematic fields. Such rheological and stress configuration evolution is expected to impact the petrophysical and permeability structure of fault zones in the study area.

Application of Vadose Zone Monitoring Technology for Characterization of Leachate Generation in Landfills

Science.gov (United States)

aharoni, imri; dahan, ofer

2016-04-01

Ground water contamination due to landfill leachate percolation is considered the most severe environmental threat related to municipal solid waste landfills. Natural waste degradation processes in landfills normally produce contaminated leachates up to decades after the waste has been buried. Studies have shown that understanding the mechanisms which govern attenuation processes and the fate of pollutants in the waste and in the underlying unsaturated zone is crucial for evaluation of environmental risks and selection of a restoration strategy. This work focuses on a closed landfill in the coastal plain of Israel that was active until 2002 without any lining infrastructure. A vadose zone monitoring system (VMS) that was implemented at the site enables continuous measurements across the waste body (15 m thick) and underlying sandy vadose zone (16 m thick). Data collected by the VMS included continuous measurements of water content as well as chemical composition of the leachates across the entire waste and vadose zone cross section. Results indicated that winter rain percolated through the waste, generating wetting waves which were observed across the waste and unsaturated sediment from land surface until groundwater at 31 m bls. Quick percolation and high fluxes were observed in spite of the clay cover that was implemented at the site as part of the rehabilitation scheme. The results show that the flow pattern is controlled by a preferential mechanism within the waste body. Specific sections showed rapid fluxes in response to rain events, while other sections remained unaffected. In the underlying sandy vadose zone the flow pattern exhibited characteristics of matrix flow. Yet, some sections received higher fluxes due to the uneven discharge of leachates from the overlying waste body. Water samples collected from the waste layer indicate production of highly polluted leachates over 14 years after the landfill was closed. The chemical composition within the waste

Comparison of lesion conspicuity of radiofrequency ablation zones among MR sequences according to time in the normal rabbit liver

International Nuclear Information System (INIS)

Ku, Myong Seo; Kim, Seung Kwon; Hong, Hyun Pyo; Kwag, Hyon Joo

2007-01-01

To compare the lesion conspicuity of radiofrequency ablation (RFA) zones among MR sequences according to time in the normal rabbit liver. RFA zones were created in 12 rabbit livers with a 17-gauge internally cooled electrode (1-cm active tip, 30 Watts, 3 minutes). Three rabbits were sacrificed immediately, three days, two weeks, and six weeks after the RFA procedure, respectively. Before sacrifice, T1-, T2-weighted images (WI), and gadolinium-enhanced (GE)-T1WI images were obtained. The lesion conspicuity of the RAF zone and the contrast-to-noise ratio (CNR) of the RFA zone to the liver parenchyma were analyzed and compared among the MR sequences according to time. On T1WI, the RFA zones were only clearly seen on acute phase. On T2WI, the RFA zones were clearly seen on all phases except the hyperacute phase. On GE T1WI, the RFA zones were clearly seen on all phases. The CNRs of the RFA zone to the liver parenchyma of GE-T1WI (8.1-12.4) were significantly higher than the CNRs of TIWI (1.6-2.7) and T2WI (1.7-6.3) on all phases (ρ < 0.05), but the visual lesion conspicuity between GE T1WI and T2WI were similar. On hyperacute phase, GE T1WI showed better lesion conspicuity of the RFA zone than T1WI and T2WI. On other phases, GE T1WI and T2WI showed similar lesion conspicuity

The Supergalactic Habitable Zone

Science.gov (United States)

Mason, Paul

2018-01-01

Habitability in the local universe is examined. Constrained by metal abundance and exposure to sterilizing events, life as we know it requires significantly long periods of stable environmental conditions. Planets within galaxies undergoing major mergers, active AGN, starburst episodes, and merging black holes pose serious threats to long-term habitability. Importantly, the development of several layers of protection from high-energy particles such as a thick atmosphere, a strong planetary magnetic field, an astrosphere, and a galactic magnetic field is of great benefit. Factors such as star type and activity, planet type and composition, the location of a planet within its host galaxy, and even the location within a supercluster of galaxies can affect the potential habitability of planets. We discuss the concept of the Supergalactic Habitable Zone introduced by Mason and Biermann in terms of habitability in the local universe and find that galaxies near the center of the Virgo cluster, for example, have a much lower probability for the development of life as we know it as compared to locations in the Milky Way.

Monitoring of thermal regime of permafrost in the coastal zone of Western Yamal

Science.gov (United States)

Vasiliev, A.

2009-04-01

Data on thermal regime of permafrost are required for estimation of the climate change influence on permafrost dynamics. Monitoring of thermal regime of permafrost was arranged in the area of weather station "Marre-Sale", western Yamal. In terms of geomorphology, the area of our observations belongs to the second and third marine terraces; the surface of these terraces has been partly modified by recent cryogenic processes. The elevation varies from 10 to 30 m a.s.l. Marine clays lie at the base of the geological section of the coastal deposits. Their upper part was eroded and uneven surface of marine sediments is overlain by continental sandy sediments. Marine clays are saline. In the southern part of study area, low accumulative islands are forming. Their heights above sea level do not exceed 0.5 meters, and during high tides their surface is covered by sea water. The sediments accumulating at these islands are saline silty clays. Western Yamal region is located within continuous permafrost zone with thickness of 150 to 200 meters. Study of thermal regime in the on-shore zone has been performed since 1979 using the 10-12-m-deep boreholes. In 2007, five boreholes were included in the work program of the Thermal State of Permafrost (TSP) project developed as a part of IPY scientific activities. According to TSP program, temperature sensors were installed at depths 2, 3, 5, and 10 meters; measurements have been performed every six hours. In this presentation, results of our observations related to climate change are discussed. For different terrain units, increase of mean annual permafrost temperature during the last 30 years has reached 0.6 to 1.5 deg. C. In the transit zone, monitoring of thermal regime have been performed since 2006. Sensors were installed at depths 0, 0.25, 0.6, 0.75, 1.25, 1.75, and 2.25 meters. The active layer depth here reaches 1.9 meters, thus the 2.25-m-sensor is located within permafrost. Monitoring data show the sharp increase in mean

Cranial vault thickness in primates: Homo erectus does not have uniquely thick vault bones.

Science.gov (United States)

Copes, Lynn E; Kimbel, William H

2016-01-01

Extremely thick cranial vaults have been noted as a diagnostic characteristic of Homo erectus since the first fossil of the species was identified, but relatively little work has been done on elucidating its etiology or variation across fossils, living humans, or extant non-human primates. Cranial vault thickness (CVT) is not a monolithic trait, and the responsiveness of its layers to environmental stimuli is unknown. We obtained measurements of cranial vault thickness in fossil hominins from the literature and supplemented those data with additional measurements taken on African fossil specimens. Total CVT and the thickness of the cortical and diploë layers individually were compared to measures of CVT in extant species measured from more than 500 CT scans of human and non-human primates. Frontal and parietal CVT in fossil primates was compared to a regression of CVT on cranial capacity calculated for extant species. Even after controlling for cranial capacity, African and Asian H. erectus do not have uniquely high frontal or parietal thickness residuals, either among hominins or extant primates. Extant primates with residual CVT thickness similar to or exceeding H. erectus (depending on the sex and bone analyzed) include Nycticebus coucang, Perodicticus potto, Alouatta caraya, Lophocebus albigena, Galago alleni, Mandrillus sphinx, and Propithecus diadema. However, the especially thick vaults of extant non-human primates that overlap with H. erectus values are composed primarily of cortical bone, while H. erectus and other hominins have diploë-dominated vault bones. Thus, the combination of thick vaults comprised of a thickened diploë layer may be a reliable autapomorphy for members of the genus Homo. Copyright © 2015 Elsevier Ltd. All rights reserved.

Internal tectonic structure of the Central American Wadati-Benioff zone based on analysis of aftershock sequences

Science.gov (United States)

Špičák, Aleš; Hanuš, Václav; Vaněk, Jiří; Běhounková, Marie

2007-09-01

Relocated Engdahl et al. (1998) global seismological data for 10 aftershock sequences were used to analyze the internal tectonic structure of the Central American subduction zone; the main shocks of several of these were the most destructive and often referenced earthquakes in the region (e.g., the 1970 Chiapas, 1983 Osa, 1992 Nicaragua, 1999 Quepos, 2001 El Salvador earthquakes). The spatial analysis of aftershock foci distribution was performed in a rotated Cartesian coordinate system (x, y, z) related to the Wadati-Benioff zone, and not in a standard coordinate system ($\\varphi$, λ, h are latitude, longitude, focal depth, respectively). Available fault plane solutions were also transformed into the plane approximating the Wadati-Benioff zone. The spatial distribution of earthquakes in each aftershock sequence was modeled as either a plane fit using a least squares approximation or a volume fit with a minimum thickness rectangular box. The analysis points to a quasi-planar distribution of earthquake foci in all aftershock sequences, manifesting the appurtenance of aftershocks to fracture zones. Geometrical parameters of fracture zones (strike, dip, and dimensions) hosting individual sequences were calculated and compared with the seafloor morphology of the Cocos Plate. The smooth character of the seafloor correlates with the aftershock fracture zones oriented parallel to the trench and commonly subparallel to the subducting slab, whereas subduction of the Cocos Ridge and seamounts around the Quepos Plateau coincides with steeply dipping fracture zones. Transformed focal mechanisms are almost exclusively (>90%) of normal character.

Distribution of Subsurface Flexure zone caused by Uemachi Fault, Japan and its activity

Science.gov (United States)

Kitada, N.; Inoue, N.; Takemura, K.; Ito, H.; Mitamura, M.

2012-12-01

In Osaka, Uemachi Fault is one of the famous active faults. It across the center of Osaka and lies in N-S direction mainly and is more than 40 km in length. The faults bound sedimentary basins, where thick sedimentary deposits of the Pliocene-Quaternary Osaka Group have accumulated. The deposits consist primarily of sand and marine and non-marine clay, and the clay layers are key markers for the interpretation of glacial and interglacial cycles. In this study, we estimate the width of the flexure zone using a geotechnical borehole database. GI database collects more than 40,000 boreholes and includes both geological information and soil properties around Osaka by the Geo-database Information Committee of Kansai Area. Our results indicate that the deformation associated with the flexure zone is distributed primarily along the splay fault (NE-SW) and not along the main fault, suggesting that the splay fault might be the primary fault at present. We first examined the borehole data along the seismic reflection line and then considered the surrounding area. An Upper Pleistocene marine clay (Ma12) is a good indicator of the flexure zone. We constructed many cross sections in and around the fault zone and classified the deformation form into three categories around the flexure zone. The results of this study allowed us to map the distribution of folding in a zone in the west of the Osaka area. Folding can be classified into three types: (1) Ma12 folding, (2) Ma12 folding that does not continue toward the hanging wall, and (3) folding or displacement of old marine clay. These folding zone trends are N-W strike however these trace are serpentine. These folding zone information are not in worth to estimate the source fault, however these zone will be more serious damaged when the earthquake occurred. Our result agrees well with the average displacement speed of about 0.4 m/ka that was derived by the Headquarters for Earthquake Research Promotion of the Ministry of Education

Thick tissue diffusion model with binding to optimize topical staining in fluorescence breast cancer margin imaging

Science.gov (United States)

Xu, Xiaochun; Kang, Soyoung; Navarro-Comes, Eric; Wang, Yu; Liu, Jonathan T. C.; Tichauer, Kenneth M.

2018-03-01

Intraoperative tumor/surgical margin assessment is required to achieve higher tumor resection rate in breast-conserving surgery. Though current histology provides incomparable accuracy in margin assessment, thin tissue sectioning and the limited field of view of microscopy makes histology too time-consuming for intraoperative applications. If thick tissue, wide-field imaging can provide an acceptable assessment of tumor cells at the surface of resected tissues, an intraoperative protocol can be developed to guide the surgery and provide immediate feedback for surgeons. Topical staining of margins with cancer-targeted molecular imaging agents has the potential to provide the sensitivity needed to see microscopic cancer on a wide-field image; however, diffusion and nonspecific retention of imaging agents in thick tissue can significantly diminish tumor contrast with conventional methods. Here, we present a mathematical model to accurately simulate nonspecific retention, binding, and diffusion of imaging agents in thick tissue topical staining to guide and optimize future thick tissue staining and imaging protocol. In order to verify the accuracy and applicability of the model, diffusion profiles of cancer targeted and untargeted (control) nanoparticles at different staining times in A431 tumor xenografts were acquired for model comparison and tuning. The initial findings suggest the existence of nonspecific retention in the tissue, especially at the tissue surface. The simulator can be used to compare the effect of nonspecific retention, receptor binding and diffusion under various conditions (tissue type, imaging agent) and provides optimal staining and imaging protocols for targeted and control imaging agent.

Experimental investigations of different steel resistances in the sodium-steam reaction zone

International Nuclear Information System (INIS)

Mazanov, A.S.; Kulpin, B.V.; Petukhov, V.P.; Ledovskikh, N.M.

1975-01-01

The results are stated on the experimental investigations of IX2M, IXI8HIOT, OXI2H2M and Sanikro-31 steel resistance in the sodium-steam reaction zone. A target in the form of a pipe was used in the experiments within which the excessive pressure of 95 atm. was produced with an inert gas. Steam was supplied through the nozzle to the sodium tank in which there was a movable target unit. The dependence of time-to failure and failure rate on the distance of the nozzle and target wall thickness was estimated for these steels. It was shown that the resistance of Sanikro-31 in the sodium steam reaction zone was 2.5, 3.5 and 6 times that of IXI8HIOT, OXI2H2M, IX2M steels, respectively. The failure curves were obtained on thin targets for two steels (author)

Observation of the Spectrally Invariant Properties of Clouds in Cloudy-to-Clear Transition Zones During the MAGIC Field Campaign

Science.gov (United States)

Yang, Weidong; Marshak, Alexander; McBride, Patrick; Chiu, J. Christine; Knyazikhin, Yuri; Schmidt, K. Sebastian; Flynn, Connor; Lewis, Ernie R.; Eloranta, Edwin W.

2016-01-01

We use the spectrally invariant method to study the variability of cloud optical thickness tau and droplet effective radius r(sub eff) in transition zones (between the cloudy and clear sky columns) observed from Solar Spectral Flux Radiometer (SSFR) and Shortwave Array Spectroradiometer-Zenith (SASZe) during the Marine ARM GPCI Investigation of Clouds (MAGIC) field campaign. The measurements from the SSFR and the SASZe are different, however inter-instrument differences of self-normalized measurements (divided by their own spectra at a fixed time) are small. The spectrally invariant method approximates the spectra in the cloud transition zone as a linear combination of definitely clear and cloudy spectra, where the coefficients, slope and intercept, characterize the spectrally invariant properties of the transition zone. Simulation results from the SBDART (Santa Barbara DISORT Atmospheric Radiative Transfer) model demonstrate that (1) the slope of the visible band is positively correlated with the cloud optical thickness t while the intercept of the near-infrared band has high negative correlation with the cloud drop effective radius r(sub eff)even without the exact knowledge of tau; (2) the above relations hold for all Solar Zenith Angle (SZA) and for cloud-contaminated skies. In observations using redundant measurements from SSFR and SASZe, we find that during cloudy-to-clear transitions, (a) the slopes of the visible band decrease, and (b) the intercepts of the near-infrared band remain almost constant near cloud edges. The findings in simulations and observations suggest that, while the optical thickness decreases during the cloudy-to-clear transition, the cloud drop effective radius does not change when cloud edges are approached. These results support the hypothesis that inhomogeneous mixing dominates near cloud edges in the studied cases.

[Study on the change of optical zone after femtosecond laser assisted laser in situ keratomileusis].

Science.gov (United States)

Li, H; Chen, M; Tian, L; Li, D W; Peng, Y S; Zhang, F F

2018-01-11

Objective: To explore the change of optical zone after femtosecond laser assisted laser in sitn keratomileusis(FS-LASIK) so as to provide the reference for measurement and design of clinical optical zone. Methods: This retrospective case series study covers 41 eyes of 24 patients (7 males and 17 females, aged from 18 to 42 years old) with myopia and myopic astigmatism who have received FS-LASIK surgery at Corneal Refractive Department of Qingdao Eye Hospital and completed over 6 months of clinical follow-up. Pentacam system (with the application of 6 corneal topographic map modes including: the pure axial curvature topographic map, the pure tangential curvature topographic map, the axial curvature difference topographic map, the tangential curvature difference topographic map, the postoperative front elevation map and the corneal thickness difference topographic map), combined with transparent concentric software (a system independently developed by Qingdao Eye Hospital) was used to measure the optical zone at 1, 3 and 6 months postoperatively, the optical zone diameters measurement results among different follow-up times in group were analyzed with the repeated measures analysis of variance, and the actual measured values and the theoretical design values of the optical zone were analyzed with independent-samples t-testing. Spearman correlation coefficient ( r(s) ) have been applied to evaluate the relationship between postoperative optical zone measurement values and the potential influencing factors. Results: The optical zone diameters measured by pure axial curvature topographic map at 1, 3 and 6 months after FS-LASIK showed (6.55±0.50)mm, (6.50±0.53)mm and (6.48±0.53)mm respectively. The differences between values are of no statistical significance ( F= 1.60, P= 0.21), the optical zone diameter measured by pure tangential curvature topographic map at 1, 3 and 6 months after FS-LASIK showed (5.44±0.46)mm, (5.46±0.52)mm and (5.44±0.50)mm respectively, the

Direct fabrication of integrated 3D Au nanobox arrays by sidewall deposition with controllable heights and thicknesses

Energy Technology Data Exchange (ETDEWEB)

Cha, Nam-Goo; Lee, Bong Kuk; Kanki, Teruo; Lee, Hea Yeon; Kawai, Tomoji; Tanaka, Hidekazu, E-mail: h-tanaka@sanken.osaka-u.ac.j [Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan)

2009-09-30

This paper provides a unique strategy for controlling integrated hollow nanostructure arrays such as boxes or pillars at the nanometer scale. The key merit of this technique is that it can overcome resolution limits by sidewall deposition and deposit various materials using a sputtering method. The sputtering method can be replaced by other dry deposition techniques such as pulsed laser deposition (PLD) for complex functional materials. Furthermore, it can produce low-cost large-area fabrication and high reproducibility using the NIL (nanoimprint lithograph) process. The fabrication method consists of a sequence of bilayer spin-coating, UV-NIL, RIE (reactive ion etching), sputtering, ion milling and piranha cleaning processes. By changing the deposition time and molds, various thicknesses and shapes can be fabricated, respectively. Furthermore, the fabricated Au box nanostructure has a bending zone of the top layer and a {approx}17 nm undercut of the bottom layer as observed by SEM (scanning electron microscope). The sidewall thickness was changed from 12 to 61 nm by controlling the deposition time, and was investigated to understand the relationship with blanket thicknesses and geometric effects. The calculated sidewall thickness matched well with experimental results. Using smaller hole-patterned molds, integrated nanobox arrays, with inner squares measuring {approx}160 nm, and nanopillar arrays, with inside pores measuring {approx}65 nm, were fabricated under the same conditions.

Conservatism in SRS Criticality Alarm System 12 Rad Zone Calculations - How Much is Enough?

International Nuclear Information System (INIS)

Yates, K.R.

2002-01-01

Savannah River Site (SRS) uses two methods (i.e., Approximate Method and MCNP) of calculating the 12-rad zone. The reasons for the two-tier approach are described in Ref. 1 and 2. Lately, there have been occasions in which the use of either the Approximate Method (AM) or MCNP3 calculations indicated potential facility impacts. For example, one or both methods may indicate that a 12-rad zone extends outside of relatively thick shielding, or extends to the roof of a facility, or extends through shielding to part of a stairwell. In such cases, a criticality alarm system may have to be installed to protect workers in a small, localized area from a potential dose that is not substantially greater than 12 rad in air. But, is the potential dose really greater than 12 rad in air? A subcommittee was appointed to look into the two 12-rad zone calculation methods for the purpose of identifying items contributing to over-conservatism and under-conservatism, and to recommend a path forward

Tear progression of symptomatic full-thickness and partial-thickness rotator cuff tears as measured by repeated MRI.

Science.gov (United States)

Kim, Yang-Soo; Kim, Sung-Eun; Bae, Sung-Ho; Lee, Hyo-Jin; Jee, Won-Hee; Park, Chang Kyun

2017-07-01

The purpose of this study was to analyse the natural course of symptomatic full-thickness and partial-thickness rotator cuff tears treated non-operatively and to identify risk factors affecting tear enlargement. One hundred and twenty-two patients who received non-surgical treatment for a partial- or full-thickness supraspinatus tear were included in this study. All rotator cuff tears were diagnosed with magnetic resonance imaging (MRI), and the same modality was used for follow-up studies. Follow-up MRI was performed after at least a 6-month interval. We evaluated the correlation between tear enlargement and follow-up duration. Eleven risk factors were analysed by both univariate and multivariate analyses to identify factors that affect enlargement of rotator cuff tears. The mean follow-up period was 24.4 ± 19.5 months. Out of 122 patients, 34 (27.9%) patients had an initial full-thickness tear and 88 (72.1%) patients had a partial-thickness tear. Considering all patients together, tear size increased in 51/122 (41.8%) patients, was unchanged in 65/122 (53.3%) patients, and decreased in 6/122 (4.9%) patients. Tear size increased for 28/34 (82.4%) patients with full-thickness tears and 23/88 (26.1%) patients with partial-thickness tears. From the two groups which were followed over 12 months, a higher rate of enlargement was observed in full-thickness tears than in partial-thickness tears (6-12 months, n.s.; 12-24 months, P = 0.002; over 24 months, P rotator cuff tears and 23/88 (26.1%) of symptomatic partial-thickness tears increased in size over a follow-up period of 6-100 months. Full-thickness tears showed a higher rate of enlargement than partial-thickness tears regardless of the follow-up duration. Univariate and multivariate analyses suggested that full-thickness tear was the most reliable risk factor for tear enlargement. The clinical relevance of these observations is that full-thickness rotator cuff tears treated conservatively should be

A Cryptic Sulfur Cycle in Oxygen-Minimum-Zone Waters off the Chilean Coast

Science.gov (United States)

Canfield, Don E.; Stewart, Frank J.; Thamdrup, Bo; De Brabandere, Loreto; Dalsgaard, Tage; Delong, Edward F.; Revsbech, Niels Peter; Ulloa, Osvaldo

2010-12-01

Nitrogen cycling is normally thought to dominate the biogeochemistry and microbial ecology of oxygen-minimum zones in marine environments. Through a combination of molecular techniques and process rate measurements, we showed that both sulfate reduction and sulfide oxidation contribute to energy flux and elemental cycling in oxygen-free waters off the coast of northern Chile. These processes may have been overlooked because in nature, the sulfide produced by sulfate reduction immediately oxidizes back to sulfate. This cryptic sulfur cycle is linked to anammox and other nitrogen cycling processes, suggesting that it may influence biogeochemical cycling in the global ocean.

Influence of slice thickness on the determination of left ventricular wall thickness and dimension by magnetic resonance imaging

Energy Technology Data Exchange (ETDEWEB)

Ohnishi, Shusaku; Fukui, Sugao; Atsumi, Chisato and others

1989-02-01

Wall thickness of the ventricular septum and left ventricle, and left ventricular cavity dimension were determined on magnetic resonance (MR) images with slices 5 mm and 10 mm in thickness. Subjects were 3 healthy volunteers and 7 patients with hypertension (4), hypertrophic cardiomyopathy (one) or valvular heart disease (2). In visualizing the cardiac structures such as left ventricular papillary muscle and right and left ventricles, 5 mm-thick images were better than 10 mm-thick images. Edges of ventricular septum and left ventricular wall were more clearly visualized on 5 mm-thick images than 10 mm-thick images. Two mm-thick MR images obtained from 2 patients yielded the most excellent visualization in end-systole, but failed to reveal cardiac structures in detail in end-diastole. Phantom studies revealed no significant differences in image quality of 10 mm and 5 mm in thickness in the axial view 80 degree to the long axis. In the axial view 45 degree to the long axis, 10 mm-thick images were inferior to 5 mm-thick images in detecting the edge of the septum and the left ventricular wall. These results indicate that the selection of slice thickness is one of the most important determinant factors in the measurement of left ventricular wall thickness and cavity dimension. (Namekawa, K).

Influence of slice thickness on the determination of left ventricular wall thickness and dimension by magnetic resonance imaging

International Nuclear Information System (INIS)

Ohnishi, Shusaku; Fukui, Sugao; Atsumi, Chisato

1989-01-01

Wall thickness of the ventricular septum and left ventricle, and left ventricular cavity dimension were determined on magnetic resonance (MR) images with slices 5 mm and 10 mm in thickness. Subjects were 3 healthy volunteers and 7 patients with hypertension (4), hypertrophic cardiomyopathy (one) or valvular heart disease (2). In visualizing the cardiac structures such as left ventricular papillary muscle and right and left ventricles, 5 mm-thick images were better than 10 mm-thick images. Edges of ventricular septum and left ventricular wall were more clearly visualized on 5 mm-thick images than 10 mm-thick images. Two mm-thick MR images obtained from 2 patients yielded the most excellent visualization in end-systole, but failed to reveal cardiac structures in detail in end-diastole. Phantom studies revealed no significant differences in image quality of 10 mm and 5 mm in thickness in the axial view 80 degree to the long axis. In the axial view 45 degree to the long axis, 10 mm-thick images were inferior to 5 mm-thick images in detecting the edge of the septum and the left ventricular wall. These results indicate that the selection of slice thickness is one of the most important determinant factors in the measurement of left ventricular wall thickness and cavity dimension. (Namekawa, K)

Reconstruction of the pre-compactional thickness of the Zechstein Main Dolomite in northwest Poland

Directory of Open Access Journals (Sweden)

Semyrka Grażyna

2015-12-01

Full Text Available Our reconstruction of the pre-compactional thickness of the Main Dolomite strata from the so-called Grotów Peninsula (northwest Poland was based on macroscopic observations of drill cores from three wells: Mokrzec-1, Sieraków-4 and Międzychód-5. These wells are located in various palaeogeographical zones of the Main Dolomite and cored rocks represent a range of microfacies. The amount of compactional reduction in thickness of the Main Dolomite was estimated by summing the total heights (Wst of all stylolites encountered in logs of these wells. For calculations, a generalised model of a drill core was developed, which embraced all types of stylolite seams present in the Main Dolomite succession studied. Also the method of stylolite dimensioning was demonstrated. The number of stylolites in the drill cores studied varied from 511 in the Sieraków-4 well to 1,534 in the Międzychód-5 well. In all cores studied low-amplitude macrostylolites predominated, but the reduction of thickness was controlled mostly by the low- and medium-amplitude macrostylolites. The largest number of stylolites was found in the grainstone/packstone microfacies. The turnout of stylolites depends of microfacies. The highest density of stylolites was documented in mudstones/wackestones (24 stylolites per metre of rock thickness and the lowest in boundstones (14 stylolites per metre of rock thickness. The low-amplitude stylolites appear most frequently in the mudstone/wackestone microfacies (15 stylolites per metre of rock thickness; in grainstones/packstones, rudstones/floatstones and boundstones middle-amplitude stylolites are rare (3 stylolites per metre of rock thickness. The degree of compaction of the Main Dolomite succession studied varied from 6 to 10%; hence, its calculated initial thickness also varied in the wells studied: from 41.3 m in the Sieraków-4 well to 56.9 m in the Mokrzec-1 well and to 97.1 m in the Międzychód-5 well. The volumes of reservoir

Platelet growth factors from allogeneic platelet-rich plasma for clinical improvement in split-thickness skin graft.

Science.gov (United States)

Sonker, Atul; Dubey, Anju; Bhatnagar, Ankur; Chaudhary, Rajendra

2015-01-01

Platelets are a source of numerous growth factors which facilitate repair and healing. Thus platelet rich plasma has been increasingly used as a treatment modality in the field of reconstructive surgeries for wound healing. This preliminary study was carried out to explore whether platelet growth factors from platelet rich plasma could be used for enhancement of split thickness skin graft survival. Twenty patients (13 males and 7 females) requiring split thickness skin graft for various clinical reasons were enrolled in the study. Platelet rich plasma was collected by apheresis and frozen at -80° C. It was thawed at room temperature immediately before its intended application. PRP was applied only on one half of the wound, while another half served as control. Patient was followed for 6 weeks. The effect was assessed at first dressing in terms of graft uptake and subsequently as time taken for complete healing. There was 100% uptake of the graft in the area where platelet rich plasma was applied. In the control area, there was complete graft loss in 4 cases, partial loss in 7 cases and complete uptake in 9 cases. This study demonstrated promising results on application of PRP to split thickness skin grafts. Further randomized studies with greater sample size may be undertaken to establish platelet rich plasma as a validated treatment modality.

Seasonal evolution of the Arctic marginal ice zone and its power-law obeying floe size distribution

Science.gov (United States)

Zhang, J.; Stern, H. L., III; Schweiger, A. J. B.; Steele, M.; Hwang, P. B.

2017-12-01

A thickness, floe size, and enthalpy distribution (TFED) sea ice model, implemented numerically into the Pan-arctic Ice-Ocean Modeling and Assimilation System (PIOMAS), is used to investigate the seasonal evolution of the Arctic marginal ice zone (MIZ) and its floe size distribution. The TFED sea ice model, by coupling the Zhang et al. [2015] sea ice floe size distribution (FSD) theory with the Thorndike et al. [1975] ice thickness distribution (ITD) theory, simulates 12-category FSD and ITD explicitly and jointly. A range of ice thickness and floe size observations were used for model calibration and validation. The model creates FSDs that generally obey a power law or upper truncated power law, as observed by satellites and aerial surveys. In this study, we will examine the role of ice fragmentation and lateral melting in altering FSDs in the Arctic MIZ. We will also investigate how changes in FSD impact the seasonal evolution of the MIZ by modifying the thermodynamic processes.

Dead zones in colloidal quantum dot photovoltaics: evidence and implications

KAUST Repository

Barkhouse, D. Aaron R.

2010-09-01

In order to fabricate photovoltaic (PV) cells incorporating light-trapping electrodes, flexible foil substrates, or more than one junction, illumination through the top-contact (i.e.: non-substrate) side of a photovoltaic device is desirable. We investigate the relative collection efficiency for illumination through the top vs. bottom of PbS colloidal quantum dot (CQD) PV devices. The external quantum efficiency spectra of FTO/TiO2/PbS CQD/ITO PV devices with various PbS layer thicknesses were measured for illumination through either the top (ITO) or bottom (FTO) contacts. By comparing the relative shapes and intensities of these spectra with those calculated from an estimation of the carrier generation profile and the internal quantum efficiency as a function of distance from the TiO2 interface in the devices, a substantial dead zone, where carrier extraction is dramatically reduced, is identified near the ITO top contact. The implications for device design, and possible means of avoiding the formation of such a dead zone, are discussed.

WorkZoneQ user guide for two-lane freeway work zones.

Science.gov (United States)

2013-06-01

WorkZoneQ was developed in Visual Basic for Applications (VBA) to implement the results of the previous study, : Queue and Users Costs in Highway Work Zones. This report contains the WorkZoneQ user guide. WorkZoneQ : consists of eight Excel ...

Delineation of marine ecosystem zones in the northern Arabian Sea during winter

Directory of Open Access Journals (Sweden)

S. Shalin

2018-03-01

Full Text Available The spatial and temporal variability of marine autotrophic abundance, expressed as chlorophyll concentration, is monitored from space and used to delineate the surface signature of marine ecosystem zones with distinct optical characteristics. An objective zoning method is presented and applied to satellite-derived Chlorophyll a (Chl a data from the northern Arabian Sea (50–75° E and 15–30° N during the winter months (November–March. Principal component analysis (PCA and cluster analysis (CA were used to statistically delineate the Chl a into zones with similar surface distribution patterns and temporal variability. The PCA identifies principal components of variability and the CA splits these into zones based on similar characteristics. Based on the temporal variability of the Chl a pattern within the study area, the statistical clustering revealed six distinct ecological zones. The obtained zones are related to the Longhurst provinces to evaluate how these compared to established ecological provinces. The Chl a variability within each zone was then compared with the variability of oceanic and atmospheric properties viz. mixed-layer depth (MLD, wind speed, sea-surface temperature (SST, photosynthetically active radiation (PAR, nitrate and dust optical thickness (DOT as an indication of atmospheric input of iron to the ocean. The analysis showed that in all zones, peak values of Chl a coincided with low SST and deep MLD. The rate of decrease in SST and the deepening of MLD are observed to trigger the algae bloom events in the first four zones. Lagged cross-correlation analysis shows that peak Chl a follows peak MLD and SST minima. The MLD time lag is shorter than the SST lag by 8 days, indicating that the cool surface conditions might have enhanced mixing, leading to increased primary production in the study area. An analysis of monthly climatological nitrate values showed increased concentrations associated with the deepening

Delineation of marine ecosystem zones in the northern Arabian Sea during winter

Science.gov (United States)

Shalin, Saleem; Samuelsen, Annette; Korosov, Anton; Menon, Nandini; Backeberg, Björn C.; Pettersson, Lasse H.

2018-03-01

The spatial and temporal variability of marine autotrophic abundance, expressed as chlorophyll concentration, is monitored from space and used to delineate the surface signature of marine ecosystem zones with distinct optical characteristics. An objective zoning method is presented and applied to satellite-derived Chlorophyll a (Chl a) data from the northern Arabian Sea (50-75° E and 15-30° N) during the winter months (November-March). Principal component analysis (PCA) and cluster analysis (CA) were used to statistically delineate the Chl a into zones with similar surface distribution patterns and temporal variability. The PCA identifies principal components of variability and the CA splits these into zones based on similar characteristics. Based on the temporal variability of the Chl a pattern within the study area, the statistical clustering revealed six distinct ecological zones. The obtained zones are related to the Longhurst provinces to evaluate how these compared to established ecological provinces. The Chl a variability within each zone was then compared with the variability of oceanic and atmospheric properties viz. mixed-layer depth (MLD), wind speed, sea-surface temperature (SST), photosynthetically active radiation (PAR), nitrate and dust optical thickness (DOT) as an indication of atmospheric input of iron to the ocean. The analysis showed that in all zones, peak values of Chl a coincided with low SST and deep MLD. The rate of decrease in SST and the deepening of MLD are observed to trigger the algae bloom events in the first four zones. Lagged cross-correlation analysis shows that peak Chl a follows peak MLD and SST minima. The MLD time lag is shorter than the SST lag by 8 days, indicating that the cool surface conditions might have enhanced mixing, leading to increased primary production in the study area. An analysis of monthly climatological nitrate values showed increased concentrations associated with the deepening of the mixed layer. The

ZoneLib

DEFF Research Database (Denmark)

Jessen, Jan Jacob; Schiøler, Henrik

2006-01-01

We present a dynamic model for climate in a livestock building divided into a number of zones, and a corresponding modular Simulink library (ZoneLib). While most literature in this area consider air flow as a control parameter we show how to model climate dynamics using actual control signals...... development of ZoneLib....

Highly efficient volume hologram multiplexing in thick dye-doped jelly-like gelatin.

Science.gov (United States)

Katarkevich, Vasili M; Rubinov, Anatoli N; Efendiev, Terlan Sh

2014-08-01

Dye-doped jelly-like gelatin is a thick-layer self-developing photosensitive medium that allows single and multiplexed volume phase holograms to be successfully recorded using pulsed laser radiation. In this Letter, we present a method for multiplexed recording of volume holograms in a dye-doped jelly-like gelatin, which provides significant increase in their diffraction efficiency. The method is based on the recovery of the photobleached dye molecule concentration in the hologram recording zone of gel, thanks to molecule diffusion from other unexposed gel areas. As an example, an optical recording of a multiplexed hologram consisting of three superimposed Bragg gratings with mean values of the diffraction efficiency and angular selectivity of ∼75% and ∼21', respectively, is demonstrated by using the proposed method.

Health-related quality of life and patient burden in patients with split-thickness skin graft donor site wounds.

Science.gov (United States)

Humrich, Marco; Goepel, Lisa; Gutknecht, Mandy; Lohrberg, David; Blessmann, Marco; Bruning, Guido; Diener, Holger; Dissemond, Joachim; Hartmann, Bernd; Augustin, Matthias

2018-04-01

Split-thickness skin grafting is a common procedure to treat different kinds of wounds. This systematic, multicentre, observational, cross-sectional study of adult patients with split-thickness skin graft (STSG) donor site wounds was conducted to evaluate quality of life (QoL) impairments caused by donor site wounds following split-thickness skin grafting. Therefore, 112 patients from 12 wound centres in Germany were examined based on patient and physician questionnaires as well as a physical examination of the donor site wound. Most indications for skin grafting were postsurgical treatment (n = 51; 42.5%) and chronic wounds (n = 47; 39.2%). European QoL visual analoque scale (EQ VAS) averaged 64.7 ± 23.3, European QoL 5 dimensions (EQ-5D) averaged 77.4 ± 30.0. Wound-QoL (range: 0-4) was rated 0.8 ± 0.8 post-surgery and 0.4 ± 0.6 at the time of survey (on average 21 weeks between the time points). Compared to averaged Wound-QoL scores of chronic wounds donor site-related QoL impairments in split-thickness skin-graft patients were less pronounced. There were significant differences in patient burden immediately after surgery compared to the time of the survey, with medium effect sizes. This supports the hypothesis that faster healing of the donor site wound leads to more favourable patient-reported outcomes. © 2017 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Development of on-line wall thickness gauge for small size seamless tube. Shokei seamless netsukan nikuatsukei no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Okumura, T; Konya, N; Oka, H; Kasuya, T [Kawasaki Steel Corp., Tokyo (Japan)

1991-03-01

In order to heighten the accuracy of small size seamless tube wall thickness, hot wall thickness gauge was developed to be installed, immediately behind the finishing/rolling mill, for the on-line measurement, of which the method was by the parallel-beam transmissivity of gamma-ray. The measurement unit, aiming at flexible manufacturing system (FMS), is completely automated in correcting the accuracy, changing the sizes, etc. The damping characteristics of gamma-ray beam can be expressed by a characteristic function, taking the outside diameter and wall thickness of subject tube as parameters. The functional calculation, as based on measurement of transmitted quantity of gamma-ray through the three-dimensional steel material, changes, depending upon the outside diameter, wall thickness and material specification of subject tube. System was so applied as to calculate it therefore on a case-by-case basis. Though in the vicinity of tube end, the transmitted quantity of gamma-ray is largely influenced by the horizontal dislocation, that influence is slack in the middle part of tube. Therefore, the cross sectional division was made dense and sparse in the end part and middle part, respectively of tube, which division could diminish the error from several percent to less than 0.1%. The static noise was compressed by the optimized digital filter. That gauge is presently applied for the operational administration of small size seamless tube rolling. 2 refs., 11 figs., 2 tabs.

Extensive formation of sinkholes in unconsolidated rock due to underground erosive removal of sand at a marginal batter of an opencast mine - causes, process and geotechnical safety measures. Grossflaechige Erdfallbildungen im Lockergestein durch unterirdische erosive Ausraeumung von Sand and einer Tagebauendboeschung - Ursachen, Verlauf und geotechnische Sicherung

Energy Technology Data Exchange (ETDEWEB)

Pfeiffer, H

1991-08-01

When the ground water rose in the marginal batter of an opencast mine damage occurred. This was caused by the processes of internal erosion and suffusion in fine sand layers of slight thickness and by the disintegration of the overlying strata due to the formation of sinkholes. Effective safety measures involved lowering the ground-water level in the zone immediately in front of the area in question and installing an auxiliary filter unit at the marginal batter. (orig.).

Nannofossil biostratigraphy, strontium and carbon isotope stratigraphy, cyclostratigraphy and an astronomically calibrated duration of the Late Campanian Radotruncana calcarata Zone.

Science.gov (United States)

Wagreich, Michael; Hohenegger, Johann; Neuhuber, Stephanie

2012-12-01

A section from the southern (Austro-Alpine Northern Calcareous Alps) margin of the Penninic Ocean in the NW Tethys realm of Late Campanian age is investigated stratigraphically. Plankton foraminifer and nannofossil biostratigraphy designate the presence of the Globotruncana ventricosa Zone and the Radotruncana ( Globotruncanita ) calcarata Zone, and standard nannofossil zones CC21-UC15c TP and CC22ab-UC15de TP . The combination of carbon isotope stratigraphy, strontium isotopes, and cyclostratigraphy allows a detailed chronostratigraphic correlation. Periodicity was obtained by power spectral analysis, sinusoidal regression, and Morlet wavelets. The duration of the calcarata Total Range Zone is calculated by orbital cyclicity expressed in thickness data of limestone-marl rhythmites and stable carbon isotope data. Precessional, obliquity, and short and long eccentricity cycles are identified and give an extent of c. 806 kyr for the zone. Mean sediment accumulation rates are as low as 1.99 cm/kyr and correspond well to sediment accumulation rates in similar settings. We further discuss chronostratigraphic implications of our data.

Effect of heat input on heat affected zone cracking in laser welded ATI Allvac 718Plus superalloy

International Nuclear Information System (INIS)

Idowu, O.A.; Ojo, O.A.; Chaturvedi, M.C.

2007-01-01

The heat affected zones (HAZs) of low and high heat input laser welds of a newly developed superalloy, ATI Allvac 718Plus, were studied. Low heat input welds suffered significant HAZ grain boundary liquation cracking, while no cracking was observed in spite of a more extensive HAZ intergranular liquation in the higher heat input welds. Combination of lower welding stresses generated during cooling, and relaxation of these stresses by thick intergranular liquid were suggested to be the factors that contributed to the absence of cracking in the high heat input welds. Further, healing of some of the HAZ cracks in lower heat input welds by fusion zone interdendritic liquid occurred through liquid backfilling

Metamorphic and geochronogical study of the Triassic El Oro metamorphic complex, Ecuador: Implications for high-temperature metamorphism in a forearc zone

Science.gov (United States)

Riel, N.; Guillot, S.; Jaillard, E.; Martelat, J.-E.; Paquette, J.-L.; Schwartz, S.; Goncalves, P.; Duclaux, G.; Thebaud, N.; Lanari, P.; Janots, E.; Yuquilema, J.

2013-01-01

In the forearc of the Andean active margin in southwest Ecuador, the El Oro metamorphic complex exhibits a well exposed tilted forearc section partially migmatized. We used Raman spectroscopy on carbonaceous matter (RSCM) thermometry and pseudosections coupled with mineralogical and textural studies to constrain the pressure-temperature (P-T) evolution of the El Oro metamorphic complex during Triassic times. Our results show that anatexis of the continental crust occurred by white-mica and biotite dehydration melting along a 10 km thick crustal domain (from 4.5 to 8 kbar) with increasing temperature from 650 to 700 °C. In the biotite dehydration melting zone, temperature was buffered at 750-820 °C in a 5 km thick layer. The estimated average thermal gradient during peak metamorphism is of 30 °C/km within the migmatitic domain can be partitioned into two apparent gradients parts. The upper part from surface to 7 km depth records a 40-45 °C/km gradient. The lower part records a quasi-adiabatic geotherm with a 10 °C/km gradient consistent with an isothermal melting zone. Migmatites U-Th-Pb geochronology yielded zircon and monazite ages of 229.3 ± 2.1 Ma and 224.5 ± 2.3 Ma, respectively. This thermal event generated S-type magmatism (the Marcabeli granitoid) and was immediately followed by underplating of the high-pressure low-temperature (HP-LT) Arenillas-Panupalí unit at 225.8 ± 1.8 Ma. The association of high-temperature low-pressure (HT-LP) migmatites with HP-LT unit constitutes a new example of a paired metamorphic belt along the South American margin. We propose that in addition to crustal thinning, underplating of the Piedras gabbroic unit before 230 Ma provided the heat source necessary to foster crustal anatexis. Furthermore, its MORB signature shows that the asthenosphere was involved as the source of the heat anomaly. S-type felsic magmatism is widespread during this time and suggests that a large-scale thermal anomaly affected a large part of the

A computational model of pile vertical vibration in saturated soil based on the radial disturbed zone of pile driving

International Nuclear Information System (INIS)

Li Qiang; Shi Qian; Wang Kuihua

2010-01-01

In this study, a simplified computational model of pile vertical vibration was developed. The model was based on the inhomogeneous radial disturbed zone of soil in the vicinity of a pile disturbed by pile driving. The model contained two regions: the disturbed zone, which was located in the immediate vicinity of the pile, and the undisturbed region, external to the disturbed zone. In the model, excess pore pressure in the disturbed zone caused by pile driving was assumed to follow a logarithmic distribution. The relationships of stress and strain in the disturbed zone were based on the principle of effective stress under plain strain conditions. The external zone was governed by the poroelastic theory proposed by Biot. With the use of a variable separation method, an analytical solution in the frequency domain was obtained. Furthermore, a semi-analytical solution was attained by employing a numerical convolution method. Numerical results from the frequency and time domain indicated that the equivalent radius of the disturbed zone and the ratio of excess pore pressure had a significant effect on pile dynamic response. However, actual interactions between pile and soil will be weaker due to the presence of the radial disturbed zone, which is caused by pile driving. Consequently, the ideal undisturbed model overestimates the interaction between pile and soil; however, the proposed model reflects the interaction of pile and soil better than the perfect contact model. Numerical results indicate that the model can account for the time effect of pile dynamic tests.

Corneal thickness: measurement and implications.

Science.gov (United States)

Ehlers, Niels; Hjortdal, Jesper

2004-03-01

The thickness of the cornea was reported in more than 100-year-old textbooks on physiological optics (Helmholtz, Gullstrand). Physiological interest was revived in the 1950s by David Maurice, and over the next 50 years, this 'simple' biological parameter has been studied extensively. Several techniques for its measurement have been described and physiological and clinical significance have been studied. In this review, the different methods and techniques of measurement are briefly presented (optical, ultrasound). While the corneal thickness of many animals are the same over a considerable part of the surface, in the human cornea anterior and posterior curvature are not concentric giving rise to a problem of definition. Based on this the precision and accuracy of determining the central corneal thickness are discussed. Changes in corneal thickness reflects changes in function of the boundary layers, in particular the endothelial barrier. The absolute value of thickness is of importance for the estimation of IOP but also in diagnosis of corneal and systemic disorders. Finally it is discussed to what extent the thickness is a biometric parameter of significance, e.g. in the progression of myopia or in the development of retinal detachment.

The Impact of Urban Development in the Arid Zone and its Management.

Science.gov (United States)

Gat, J. R.

2002-05-01

From the experience in humid and semi-arid settings, the immediate impact of urbanization on the hydrological system is the interference with the natural direct infiltration pathways, resulting in a decrease of groundwater recharge as well as the possibility of surface flooding. In contrast, in the arid environment the limited rain amounts and number of rain events makes the contribution of rain of marginal importance in the city's water balance. The major impact of urbanization in the arid zone is the continuous excess of discharge of treated or untreated sewage or water spills, originating from the import of water to the city's water supply. Their effect can be advantageous if properly channeled. On the other hand, the polluting potential of these water excesses as well as the possibility of mobilizing stored salinity in the downstream locations is of concern, if the natural drainage network and its remediation capacity becomes overloaded. Further, since the arid zone hydrological cycle depends naturally on a discontinuous and episodal groundwater recharge pattern, the new situation requires the re-assessment of the eco-hydrological patterns in the downstream location.

Forced in-plane vibration of a thick ring on a unilateral elastic foundation

Science.gov (United States)

Wang, Chunjian; Ayalew, Beshah; Rhyne, Timothy; Cron, Steve; Dailliez, Benoit

2016-10-01

Most existing studies of a deformable ring on elastic foundation rely on the assumption of a linear foundation. These assumptions are insufficient in cases where the foundation may have a unilateral stiffness that vanishes in compression or tension such as in non-pneumatic tires and bushing bearings. This paper analyzes the in-plane dynamics of such a thick ring on a unilateral elastic foundation, specifically, on a two-parameter unilateral elastic foundation, where the stiffness of the foundation is treated as linear in the circumferential direction but unilateral (i.e. collapsible or tensionless) in the radial direction. The thick ring is modeled as an orthotropic and extensible circular Timoshenko beam. An arbitrarily distributed time-varying in-plane force is considered as the excitation. The Equations of Motion are explicitly derived and a solution method is proposed that uses an implicit Newmark scheme for the time domain solution and an iterative compensation approach to determine the unilateral zone of the foundation at each time step. The dynamic axle force transmission is also analyzed. Illustrative forced vibration responses obtained from the proposed model and solution method are compared with those obtained from a finite element model.

Evaluating steady-state soil thickness by coupling uranium series and 10Be cosmogenic radionuclides

Science.gov (United States)

Vanacker, Veerle; Schoonejans, Jerome; Opfergelt, Sophie; Granet, Matthieu; Christl, Marcus; Chabaux, Francois

2017-04-01

Within the Critical Zone, the development of the regolith mantle is controlled by the downwards propagation of the weathering front into the bedrock and denudation at the surface of the regolith by mass movements, water and wind erosion. When the removal of surface material is approximately balanced by the soil production, the soil system is assumed to be in steady-state. The steady state soil thickness (or so-called SSST) can be considered as a dynamic equilibrium of the system, where the thickness of the soil mantle stays relatively constant over time. In this study, we present and compare analytical data from two independent isotopic techniques: in-situ produced cosmogenic nuclides and U-series disequilibria to constrain soil development under semi-arid climatic conditions. The Spanish Betic Cordillera (Southeast Spain) was selected for this study, as it offers us a unique opportunity to analyze soil thickness steady-state conditions for thin soils of semiarid environments. Three soil profiles were sampled across the Betic Ranges, at the ridge crest of zero-order catchments with distinct topographic relief, hillslope gradient and 10Be-derived denudation rate. The magnitude of soil production rates determined based on U-series isotopes (238U, 234U, 230Th and 226Ra) is in the same order of magnitude as the 10Be-derived denudation rates, suggesting steady state soil thickness in two out of three sampling sites. The results suggest that coupling U-series isotopes with in-situ produced radionuclides can provide new insights in the rates of soil development; and also illustrate the potential frontiers in applying U-series disequilibria to track soil production in rapidly eroding landscapes characterized by thin weathering depths.

Three-dimensional primate molar enamel thickness.

Science.gov (United States)

Olejniczak, Anthony J; Tafforeau, Paul; Feeney, Robin N M; Martin, Lawrence B

2008-02-01

Molar enamel thickness has played an important role in the taxonomic, phylogenetic, and dietary assessments of fossil primate teeth for nearly 90 years. Despite the frequency with which enamel thickness is discussed in paleoanthropological discourse, methods used to attain information about enamel thickness are destructive and record information from only a single plane of section. Such semidestructive planar methods limit sample sizes and ignore dimensional data that may be culled from the entire length of a tooth. In light of recently developed techniques to investigate enamel thickness in 3D and the frequent use of enamel thickness in dietary and phylogenetic interpretations of living and fossil primates, the study presented here aims to produce and make available to other researchers a database of 3D enamel thickness measurements of primate molars (n=182 molars). The 3D enamel thickness measurements reported here generally agree with 2D studies. Hominoids show a broad range of relative enamel thicknesses, and cercopithecoids have relatively thicker enamel than ceboids, which in turn have relatively thicker enamel than strepsirrhine primates, on average. Past studies performed using 2D sections appear to have accurately diagnosed the 3D relative enamel thickness condition in great apes and humans: Gorilla has the relatively thinnest enamel, Pan has relatively thinner enamel than Pongo, and Homo has the relatively thickest enamel. Although the data set presented here has some taxonomic gaps, it may serve as a useful reference for researchers investigating enamel thickness in fossil taxa and studies of primate gnathic biology.

Empowerment Zones and Enterprise Districts - MDC_EnterpriseZone

Data.gov (United States)

NSGIC Local Govt | GIS Inventory — Polygon feature class of Miami Dade County Enterprise Zones. Enterprise Zones are special areas in the county where certain incentives from the State are available...

Determination of cartilage thickness in the ankle joint. MRT (1,5 T) comparative anatomical study; Bestimmung der Knorpeldicke am oberen Sprunggelenk. Eine MRT(1,5 T)-anatomische Vergleichsstudie

Energy Technology Data Exchange (ETDEWEB)

Trattnig, S. [Universitaetsklinik fuer Radiodiagnostik, Wien (Austria). Klinische Einrichtung Magnet Resonanz und Abt. fuer Osteoradiologie]|[Ludwig Boltzmann Inst. fuer Radiologische Tumordiagnostik, Wien (Austria); Breitenseher, M.J. [Universitaetsklinik fuer Radiodiagnostik, Wien (Austria). Klinische Einrichtung Magnet Resonanz und Abt. fuer Osteoradiologie]|[Ludwig Boltzmann Inst. fuer Radiologische Tumordiagnostik, Wien (Austria); Huber, M. [Pathologisch-Bakteriologisches Inst. Baumgartner Hoehe, Wien (Austria); Zettl, R. [Orthopaedisches Krankenhaus Gersthof, Wien (Austria); Rottmann, B. [Universitaetsklinik fuer Radiodiagnostik, Wien (Austria). Klinische Einrichtung Magnet Resonanz und Abt. fuer Osteoradiologie]|[Ludwig Boltzmann Inst. fuer Radiologische Tumordiagnostik, Wien (Austria); Haller, J. [Hanuschkrankenhaus, Wien (Austria). Radiologische Abt.; Imhof, H. [Universitaetsklinik fuer Radiodiagnostik, Wien (Austria). Klinische Einrichtung Magnet Resonanz und Abt. fuer Osteoradiologie]|[Ludwig Boltzmann Inst. fuer Radiologische Tumordiagnostik, Wien (Austria)

1997-04-01

Purpose: The aim of this study was to evaluate the accuracy of MRI in the measurement of cartilage thickness of the ankle joint in comparison to pathologic and histologic specimens. Patients and methods: The ankle joints of four fresh cadaver feet were imaged on a 1.5 T MR-unit in the coronal plane. Standard T{sub 1}-weighted spin echo (SE) and a T{sub 1}-weighted 3D-GE (FLASH-3D) sequence with fat saturation were applied. Following MR imaging, the talus was explanted and cut parallel to the MR images for macroscopic evaluation and histologic specimens were prepared. MRI measurements of the cartilage thickness of the talus were carried out in two ways: Without and with consideration of a transition zone of intermediate signal intensity between hyperintense cartilage and hypointense cortical bone. The data were compared with the anatomic specimens as the gold standard expressing the difference as a percentage value. On histologic specimens thickness of deep calcified cartilage layer was measured. Results: Measurements without the transition zone showed a mean underestimation of talus cartilage thickness of 46.8% (41.3-52.1) for T{sub 1}-SE and 47.5% (43.1-52.1) for fat saturated FLASH-3D images. Considering the transition zone the mean values were 25.0% (23.1-26.2) and 14.1% (6.7-21.5). The histologic specimens showed a three-fold increase of thickness of deep calcified cartilage layer. Conclusions: Measurements of the cartilage layer of the ankle joint on MR images are only accurate if the transition zone (calcified cartilage layer) is considered and the optimal pulse sequence (FLASH-3D-fat-sat) is applied. (orig.) [Deutsch] Ziel: Die Frage, ob die MRT die Dicke des Knorpels exakt bestimmen kann, wird kontrovers diskutiert. Ziel der Studie war die Bestimmung der Knorpeldicke am oberen Sprunggelenk mit der MRT im Vergleich zum anatomischen Praeparat. Material und Methode: Sprunggelenke von 4 Leichen wurden auf einem 1,5 Tesla MR-Geraet mittels T{sub 1}-betonter Spin

Utilization of high resolution satellite geoid data for estimation of lithospheric thickness in the Bay of Bengal

Digital Repository Service at National Institute of Oceanography (India)

Majumdar, T.J.; Bhattacharyya, R.; Chatterjee, S.; Krishna, K.S.

been estimated using residual geoid data. In a similar fashion, the age offset from the age contours have been observed. (Figs. 5 a and b). Geoid models for ocean ridges and fracture zones If h(t) is the blope is the geoid as a function of seafloor... age, resulting from changes in seafloor depth and plate thickness due to cooling, then the quantity (∆h/age offset) estimated above is simply the derivative of h(t) with respect to age, where t is the mean age between two sides of a fracture8. From...

Thickly Syndetical Sensitivity of Topological Dynamical System

Directory of Open Access Journals (Sweden)

Heng Liu

2014-01-01

Full Text Available Consider the surjective continuous map f:X→X, where X is a compact metric space. In this paper we give several stronger versions of sensitivity, such as thick sensitivity, syndetic sensitivity, thickly syndetic sensitivity, and strong sensitivity. We establish the following. (1 If (X,f is minimal and sensitive, then (X,f is syndetically sensitive. (2 Weak mixing implies thick sensitivity. (3 If (X,f is minimal and weakly mixing, then it is thickly syndetically sensitive. (4 If (X,f is a nonminimal M-system, then it is thickly syndetically sensitive. Devaney chaos implies thickly periodic sensitivity. (5 We give a syndetically sensitive system which is not thickly sensitive. (6 We give thickly syndetically sensitive examples but not cofinitely sensitive ones.

Electromagnetic exploration in high-salinity groundwater zones: case studies from volcanic and soft sedimentary sites in coastal Japan

Science.gov (United States)

Suzuki, Koichi; Kusano, Yukiko; Ochi, Ryota; Nishiyama, Nariaki; Tokunaga, Tomochika; Tanaka, Kazuhiro

2017-01-01

Estimating the spatial distribution of groundwater salinity in coastal plain regions is becoming increasingly important for site characterisation and the prediction of hydrogeological environmental conditions resulting from radioactive waste disposal and underground CO2 storage. In previous studies of the freshwater-saltwater interface, electromagnetic methods were used for sites characterised by unconsolidated deposits or Neocene soft sedimentary rocks. However, investigating the freshwater-saltwater interface in hard rock sites (e.g. igneous areas) is more complex, with the permeability of the rocks greatly influenced by fractures. In this study, we investigated the distribution of high-salinity groundwater at two volcanic rock sites and one sedimentary rock site, each characterised by different hydrogeological features. Our investigations included (1) applying the controlled source audio-frequency magnetotelluric (CSAMT) method and (2) conducting laboratory tests to measure the electrical properties of rock core samples. We interpreted the 2D resistivity sections by referring to previous data on geology and geochemistry of groundwater. At the Tokusa site, an area of inland volcanic rocks, low resistivity zones were detected along a fault running through volcanic rocks and shallow sediments. The results suggest that fluids rise through the Tokusa-Jifuku Fault to penetrate shallow sediments in a direction parallel to the river, and some fluids are diluted by rainwater. At the Oki site, a volcanic island on a continental shelf, four resistivity zones (in upward succession: low, high, low and high) were detected. The results suggest that these four zones were formed during a transgression-regression cycle caused by the last glacial period. At the Saijo site, located on a coastal plain composed of thick sediments, we observed a deep low resistivity zone, indicative of fossil seawater remnant from a transgression after the last glacial period. The current coastal

Ultrasonic TOFD method application for steel components and welds of 10 mm wall thickness using ultrasonic flaw detector and ULTRA7 TOFD software

International Nuclear Information System (INIS)

Kasarov, R.; Tabakova, B.

2008-01-01

Pressure Vessels inspection is carried out using complex of NDT techniques. A relatively recent technique ultrasonic NDJ is the Time-of-Flight Diffraction (TOFD,) method as an effective method for detection and sizing of flaws. One of the way inspection heavy duty steel elements and welds is to use manual TOFD technique with longitudinal waves at refracted angles of 45 to 70 degrees. Typically inspections using this method have been on steel elements and welds varying from 12 mm to 300 mm wall thickness. In this paper is presented examples of using the TOFD techniques for 10 mm wall thickness using USM 35X5 and ULTRA-7 TOFD software. This software provides TOFD inspection design (PCS, sound path, beam coverage, dead zones) and validation services. The calculations of the two dead zones are derived from relatively trigonometric equation, graphically displayed on a PC-screen and weld frame form. Using ULTRA-7 TOFD the user must move the gate at which the flaw is located on PC-screen to determine the depth of defect. The diffraction points graphically displayed in a weld frame form and analyzed using geometry calculations. (authors)

Slip Zone versus Damage Zone Micromechanics, Arima-Takasuki Tectonic Line, Japan

Science.gov (United States)

White, J. C.; Lin, A.

2017-12-01

The Arima-Takasuki Tectonic Line (ATTL) of southern Honshu, Japan is defined by historically active faults and multiple splays producing M7 earthquakes. The damage zone of the ATTL comprises a broad zone of crushed, comminuted and pulverized granite/rhyolite1,2containing cm-scale slip zones and highly comminuted injection veins. In this presentation, prior work on the ATTL fault rocks is extending to include microstructural characterization by transmission electron microscopy (TEM) from recent trenching of the primary slip zone, as well as secondary slip zones. This is necessary to adequately characterize the extremely fine-grained material (typically less than 1mm) in both damage and core zones. Damage zone material exhibits generally random textures3 whereas slip zones are macroscopically foliated, and compositionally layered, notwithstanding a fairly homogeneous protolith. The latter reflects fluid-rock interaction during both coseismic and interseismic periods. The slip zones are microstructurally heterogeneous at all scales, comprising not only cataclasites and phyllosilicate (clay)-rich gouge zones, but Fe/Mn pellets or clasts that are contained within gouge. These structures appear to have rolled and would suggest rapid recrystallization and/or growth. A central question related to earthquake recurrence along existing faults is the nature of the gouge. In both near-surface exposures and ongoing drilling at depth, "plastic" or "viscous" gouge zones comprise ultra-fine-grained clay-siliciclastic particles that would not necessarily respond in a simple frictional manner. Depending on whether the plastic nature of these slip zones develops during or after slip, subsequent focusing of slip within them could be complicated. 1 Mitchell, T.A., Ben-Zion, Y., Shimamoto, T., 2011. Ear. Planet. Sci. Lett. 308, 284-297. 2 Lin, A., Yamashita, K, Tanaka, M. J., 2013. Struc. Geol. 48, 3-13. 3 White, J.C., Lin, A. 2016. Proc. AGU Fall Mtg., T42-02 San Francisco.

Development of Characterization Technology for Fault Zone Hydrology

International Nuclear Information System (INIS)

Karasaki, Kenzi; Onishi, Tiemi; Gasperikova, Erika; Goto, Junichi; Tsuchi, Hiroyuki; Miwa, Tadashi; Ueta, Keiichi; Kiho, Kenzo; Miyakawa, Kimio

2010-01-01

Several deep trenches were cut, and a number of geophysical surveys were conducted across the Wildcat Fault in the hills east of Berkeley, California. The Wildcat Fault is believed to be a strike-slip fault and a member of the Hayward Fault System, with over 10 km of displacement. So far, three boreholes of ∼ 150m deep have been core-drilled and borehole geophysical logs were conducted. The rocks are extensively sheared and fractured; gouges were observed at several depths and a thick cataclasitic zone was also observed. While confirming some earlier, published conclusions from shallow observations about Wildcat, some unexpected findings were encountered. Preliminary analysis indicates that Wildcat near the field site consists of multiple faults. The hydraulic test data suggest the dual properties of the hydrologic structure of the fault zone. A fourth borehole is planned to penetrate the main fault believed to lie in-between the holes. The main philosophy behind our approach for the hydrologic characterization of such a complex fractured system is to let the system take its own average and monitor a long term behavior instead of collecting a multitude of data at small length and time scales, or at a discrete fracture scale and to 'up-scale,' which is extremely tenuous.

Evaluation of Ohio work zone speed zones process.

Science.gov (United States)

2014-06-01

This report describes the methodology and results of analyses performed to determine the effectiveness of Ohio Department of Transportation processes for establishing work zone speed zones. Researchers observed motorists speed choice upstream of a...

The impact of hydrogen enrichment and bluff-body lip thickness on characteristics of blended propane/hydrogen bluff-body stabilized turbulent diffusion flames

International Nuclear Information System (INIS)

Kashir, Babak; Tabejamaat, Sadegh; Jalalatian, Nafiseh

2015-01-01

Highlights: • Characteristics of C 3 H 8 –H 2 bluff-body stabilized flames are investigated. • Decreasing the bluff-body lip thickness led into enhanced flame length. • CO mass fraction is increased with reducing hydrogen content in the fuel stream. • Augmenting hydrogen content increased the maximum temperature. • Jet-like zone in propane–hydrogen bluff-body stabilized flames is very unstable. - Abstract: At the beginning of this study, the well-known turbulent bluff-body stabilized diffusion flame of HM1 is simulated by a coupled flamelet/radiation approach. The HM1 flame comprises a CH 4 :H 2 [50:50 Vol.] jet flame at a Reynolds number of 15,800. The results showed reasonable agreement for the flow field and species. Afterwards, the abovementioned approach is employed to investigate the effects of hydrogen addition on bluff-body stabilized flames of propane–hydrogen. Adding hydrogen to the blended fuel of propane/hydrogen shifts the recirculation zone outwards the bluff-body and thus culminates in increased flame length. Besides this, the flame length is predicted to be enhanced with decreasing the lip thickness of the bluff-body configuration. The CO emission level is found to be decreased with hydrogen addition in near-burner and far field regions which might be attributed to the decrease of inflow carbon atoms. The local radiative heat power reveals higher values for fuel blends with decreased contents of hydrogen at the recirculation and jet-like zones. This might be attributed to the increased local heat release rate due to breaking further carbon bonds

Education and "Thick" Epistemology

Science.gov (United States)

Kotzee, Ben

2011-01-01

In this essay Ben Kotzee addresses the implications of Bernard Williams's distinction between "thick" and "thin" concepts in ethics for epistemology and for education. Kotzee holds that, as in the case of ethics, one may distinguish between "thick" and "thin" concepts of epistemology and, further, that this distinction points to the importance of…

Rupture Complexity Promoted by Damaged Fault Zones in Earthquake Cycle Models

Science.gov (United States)

Idini, B.; Ampuero, J. P.

2017-12-01

Pulse-like ruptures tend to be more sensitive to stress heterogeneity than crack-like ones. For instance, a stress-barrier can more easily stop the propagation of a pulse than that of a crack. While crack-like ruptures tend to homogenize the stress field within their rupture area, pulse-like ruptures develop heterogeneous stress fields. This feature of pulse-like ruptures can potentially lead to complex seismicity with a wide range of magnitudes akin to the Gutenberg-Richter law. Previous models required a friction law with severe velocity-weakening to develop pulses and complex seismicity. Recent dynamic rupture simulations show that the presence of a damaged zone around a fault can induce pulse-like rupture, even under a simple slip-weakening friction law, although the mechanism depends strongly on initial stress conditions. Here we aim at testing if fault zone damage is a sufficient ingredient to generate complex seismicity. In particular, we investigate the effects of damaged fault zones on the emergence and sustainability of pulse-like ruptures throughout multiple earthquake cycles, regardless of initial conditions. We consider a fault bisecting a homogeneous low-rigidity layer (the damaged zone) embedded in an intact medium. We conduct a series of earthquake cycle simulations to investigate the effects of two fault zone properties: damage level D and thickness H. The simulations are based on classical rate-and-state friction, the quasi-dynamic approximation and the software QDYN (https://github.com/ydluo/qdyn). Selected fully-dynamic simulations are also performed with a spectral element method. Our numerical results show the development of complex rupture patterns in some damaged fault configurations, including events of different sizes, as well as pulse-like, multi-pulse and hybrid pulse-crack ruptures. We further apply elasto-static theory to assess how D and H affect ruptures with constant stress drop, in particular the flatness of their slip profile

Optical instrument for measurement of vaginal coating thickness by drug delivery formulations

International Nuclear Information System (INIS)

Henderson, Marcus H.; Peters, Jennifer J.; Walmer, David K.; Couchman, Grace M.; Katz, David F.

2005-01-01

An optical device has been developed for imaging the human vaginal epithelial surfaces, and quantitatively measuring distributions of coating thickness of drug delivery formulations - such as gels - applied for prophylaxis, contraception or therapy. The device consists of a rigid endoscope contained within a 27-mm-diam hollow, polished-transparent polycarbonate tube (150 mm long) with a hemispherical cap. Illumination is from a xenon arc. The device is inserted into, and remains stationary within the vagina. A custom gearing mechanism moves the endoscope relative to the tube, so that it views epithelial surfaces immediately apposing its outer surface (i.e., 150 mm long by 360 deg. azimuthal angle). Thus, with the tube fixed relative to the vagina, the endoscope sites local regions at distinct and measurable locations that span the vaginal epithelium. The returning light path is split between a video camera and photomultiplier. Excitation and emission filters in the light path enable measurement of fluorescence of the sited region. Thus, the instrument captures video images simultaneously with photometric measurement of fluorescence of each video field [∼10 mm diameter; formulations are labeled with 0.1% w/w United States Pharmacoepia (USP) injectable sodium fluorescein]. Position, time and fluorescence measurements are continuously displayed (on video) and recorded (to a computer database). The photomultiplier output is digitized to quantify fluorescence of the endoscope field of view. Quantification of the thickness of formulation coating of a surface sited by the device is achieved due to the linear relationship between thickness and fluorescence intensity for biologically relevant thin layers (of the order of 0.5 mm). Summary measures of coating have been developed, focusing upon extent, location and uniformity. The device has begun to be applied in human studies of model formulations for prophylaxis against infection with HIV and other sexually transmitted

Relationship between macular ganglion cell complex thickness and macular outer retinal thickness: a spectral-domain optical coherence tomography study.

Science.gov (United States)

Kita, Yoshiyuki; Kita, Ritsuko; Takeyama, Asuka; Anraku, Ayako; Tomita, Goji; Goldberg, Ivan

2013-01-01

To assess the relationship between macular ganglion cell complex and macular outer retinal thicknesses. Case-control study. Forty-two normal eyes and 91 eyes with primary open-angle glaucoma were studied. Spectral-domain optical coherence tomography (RTVue-100) was used to measure the macular ganglion cell complex and macular outer retinal thickness. Ganglion cell complex to outer retinal thickness ratio was also calculated. The relationships between the ganglion cell complex and outer retinal thicknesses and between the ganglion cell complex to outer retinal thickness ratio and outer retinal thickness were evaluated. There was a positive correlation between ganglion cell complex and outer retinal thicknesses in the normal group and the glaucoma group (r = 0.53, P variation in the outer retinal thickness. Therefore, when determining the ganglion cell complex, it seems necessary to consider the outer retinal thickness as well. We propose the ratio as a suitable parameter to account for individual variations in outer retinal thickness. © 2013 The Authors. Clinical and Experimental Ophthalmology © 2013 Royal Australian and New Zealand College of Ophthalmologists.

Sense of shear and displacement estimates in the Abeibara-Rarhous late Pan-African shear zone, Adrar des Iforas, Mali

Science.gov (United States)

Boullier, Anne-Marie

The late Pan-African Abeibara-Rarhous shear zone in the Adrar des Iforas (Mali) is described and studied with the aim of defining the direction, sense of movement and amount of displacement along the zone. It is a strike-slip shear zone, the dextral sense of which is demonstrated at the scale of the map by the rotation of the related mylonitic foliation and at the scale of the thin section with characteristic microstructures. Preferred orientation of quartz c-axes is tentatively used; three quartz-rich samples of 35% or more quartz indicate dextral strike-slip movement, but other samples do not show preferred orientation of quartz c-axes. Strain measurements have been performed on one half of the shear zone using established techniques and a new technique using the thickness of mylonitic layering. The results vary along the length of the shear zone when using the same method and for the same cross-section when using the three methods together. A mean value of 4 km is obtained for total displacement which is low when considering the apparent width of the shear zone. This result is discussed in view of the assumptions involved in the strain estimation. The tectonic history of the Abeibara-Rarhous shear zone and its significance in the Trans-Saharan Pan-African collisional belt are discussed.

Microstructure and pitting corrosion of friction stir welded joints in 2219-O aluminum alloy thick plate

International Nuclear Information System (INIS)

Xu Weifeng; Liu Jinhe

2009-01-01

Effect of welding parameters on the microstructure and pitting corrosion of different positions along the thickness of weld nugget zone in friction stir welded 2219-O aluminum alloy plate was investigated using scanning electron microscopy (SEM), polarization experiment and electrochemical impedance tests (EIS). It was found that the material presents significant passivation and the top has best corrosion resistance compared to the bottom and base material. Corrosion resistance decreases with the increase of traverse speed from 60 to 100 mm/min at rotary speed 400 rpm. Corrosion resistance at rotary speed 600 rpm is lower than that at 500 rpm.

One-Stage Immediate Breast Reconstruction: A Concise Review

Directory of Open Access Journals (Sweden)

Nicolò Bertozzi

2017-01-01

Full Text Available Background. One-stage direct-to-implant immediate breast reconstruction (IBR is performed simultaneously with breast cancer resection. We explored indications, techniques, and outcomes of IBR to determine its feasibility, safety, and effectiveness. Material and Methods. We reviewed the available literature on one-stage direct-to-implant IBR, with or without acellular dermal matrix (ADM, synthetic mesh, or autologous fat grafting. We analyzed the indications, preoperative work-up, surgical technique, postoperative care, outcomes, and complications. Results. IBR is indicated for small-to-medium nonptotic breasts and contraindicated in patients who require or have undergone radiotherapy, due to unacceptably high complications rates. Only patients with thick, well-vascularized mastectomy flaps are IBR candidates. Expandable implants should be used for ptotic breasts, while anatomical shaped implants should be used to reconstruct small-to-medium nonptotic breasts. ADMs can be used to cover the implant during IBR and avoid muscle elevation, thereby minimizing postoperative pain. Flap necrosis, reoperation, and implant loss are more common with IBR than conventional two-staged reconstruction, but IBR has advantages such as lack of secondary surgery, faster recovery, and better quality of life. Conclusions. IBR has good outcomes and patient-satisfaction rates. With ADM use, a shift from conventional reconstruction to IBR has occurred. Drawbacks of IBR can be overcome by careful patient selection.

Use of buffy coat thick films in detecting malaria parasites in patients with negative conventional thick films.

Science.gov (United States)

Duangdee, Chatnapa; Tangpukdee, Noppadon; Krudsood, Srivicha; Wilairatana, Polrat

2012-04-01

To determine the frequency of malaria parasite detection from the buffy coat blood films by using capillary tube in falciparum malaria patients with negative conventional thick films. Thirty six uncomplicated falciparum malaria patients confirmed by conventional thick and thin films were included in the study. The patients were treated with artemisinin combination therapy at Hospital for Tropical Diseases, Bangkok, Thailand for 28 day. Fingerpricks for conventional blood films were conducted every 6 hours until negative parasitemia, then daily fingerpricks for parasite checks were conducted until the patients were discharged from hospital. Blood samples were also concurrently collected in 3 heparinized capillary tubes at the same time of fingerpricks for conventional blood films when the prior parasitemia was negative on thin films and parasitemia was lower than 50 parasites/200 white blood cells by thick film. The first negative conventional thick films were compared with buffy coat thick films for parasite identification. Out of 36 patients with thick films showing negative for asexual forms of parasites, buffy coat films could detect remaining 10 patients (27.8%) with asexual forms of Plasmodium falciparum. The study shows that buffy coat thick films are useful and can detect malarial parasites in 27.8% of patients whose conventional thick films show negative parasitemia.

Confocal absorption spectral imaging of MoS2: optical transitions depending on the atomic thickness of intrinsic and chemically doped MoS2.

Science.gov (United States)

Dhakal, Krishna P; Duong, Dinh Loc; Lee, Jubok; Nam, Honggi; Kim, Minsu; Kan, Min; Lee, Young Hee; Kim, Jeongyong

2014-11-07

We performed a nanoscale confocal absorption spectral imaging to obtain the full absorption spectra (over the range 1.5-3.2 eV) within regions having different numbers of layers and studied the variation of optical transition depending on the atomic thickness of the MoS2 film. Three distinct absorption bands corresponding to A and B excitons and a high-energy background (BG) peak at 2.84 eV displayed a gradual redshift as the MoS2 film thickness increased from the monolayer, to the bilayer, to the bulk MoS2 and this shift was attributed to the reduction of the gap energy in the Brillouin zone at the K-point as the atomic thickness increased. We also performed n-type chemical doping of MoS2 films using reduced benzyl viologen (BV) and the confocal absorption spectra modified by the doping showed a strong dependence on the atomic thickness: A and B exciton peaks were greatly quenched in the monolayer MoS2 while much less effect was shown in larger thickness and the BG peak either showed very small quenching for 1 L MoS2 or remained constant for larger thicknesses. Our results indicate that confocal absorption spectral imaging can provide comprehensive information on optical transitions of microscopic size intrinsic and doped two-dimensional layered materials.

Two new ways of mapping sea ice thickness using ocean waves

Science.gov (United States)

Wadhams, P.

2010-12-01

TWO NEW METHODS OF MAPPING SEA ICE THICKNESS USING OCEAN WAVES. P. Wadhams (1,2), Martin Doble (1,2) and F. Parmiggiani (3) (1) Dept. of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge CB3 0WA, UK. (2) Laboratoire d’Océanographie de Villefranche, Université Pierre et Marie Curie, 06234 Villefranche-sur-Mer, France (2) ISAC-CNR, Bologna, Italy Two new methods of mapping ice thickness have been recently developed and tested, both making use of the dispersion relation of ocean waves in ice of radically different types. In frazil-pancake ice, a young ice type in which cakes less than 5 m across float in a suspension of individual ice crystals, the propagation of waves has been successfully modelled by treating the ice layer as a highly viscous fluid. The model predicts a shortening of wavelengths within the ice. Two-dimensional Fourier analysis of successive SAR subscenes to track the directional spectrum of a wave field as it enters an ice edge shows that waves do indeed shorten within the ice, and the change has been successfully used to predict the thickness of the frazil-pancake layer. Concurrent shipborne sampling in the Antarctic has shown that the method is accurate, and we now propose its use throughout the important frazil-pancake regimes in the world ocean (Antarctic circumpolar ice edge zone, Greenland Sea, Bering Sea and others). A radically different type of dispersion occurs when ocean waves enter the continuous icefields of the central Arctic, when they couple with the elastic ice cover to propagate as a flexural-gravity wave. A two-axis tiltmeter array has been used to measure the resulting change in the dispersion relation for long ocean swell (15-30 s) originating from storms in the Greenland Sea. The dispersion relation is slightly different from swell in the open ocean, so if two such arrays are placed a substantial distance (100s of km) apart and used to observe the changing wave period of arrivals from a given

Effect of the Ti-Nanolayer Thickness on the Self-Lift-off of Thick GaN Epitaxial Layers

International Nuclear Information System (INIS)

Yugov, A. A.; Malahov, S. S.; Donskov, A. A.; Duhnovskii, M. P.; Knyazev, S. N.; Kozlova, Yu. P.; Yugova, T. G.; Belogorokhov, I. A.

2016-01-01

The effect of the type of substrate, sapphire substrate (c- and r-orientation) or GaN/Al_2O_3 template (c- and r-orientations), on the nitridation of an amorphous titanium nanolayer is shown. The effect of the titanium-nanolayer thickness on thick GaN epitaxial layer self-separation from the substrate is revealed. The titanium-nanolayer thickness at which thick GaN layer is reproducibly self-separated is within 20–40 nm.

Architecture of a low-angle normal fault zone, southern Basin and Range (SE California)

Science.gov (United States)

Goyette, J. A.; John, B. E.; Campbell-Stone, E.; Stunitz, H.; Heilbronner, R.; Pec, M.

2009-12-01

Exposures of the denuded Cenozoic detachment fault system in the southern Sacramento Mountains (SE California) delimit the architecture of a regional low-angle normal fault, and highlight the evolution of these enigmatic faults. The fault was initiated ~23 Ma in quartzo-feldspathic basement gneiss and granitoids at a low-angle (2km, and amplitudes up to 100m. These corrugations are continuous along their hinges for up to 3.6 km. Damage zone fracture intensity varies both laterally, and perpendicular to the fault plane (over an area of 25km2), decreasing with depth in the footwall, and varies as a function of lithology and proximity to corrugation walls. Deformation is concentrated into narrow damage zones (100m) are found in areas where low-fracture intensity horses are corralled by sub-horizontal zones of cataclasite (up to 8m) and thick zones of epidote (up to 20cm) and silica-rich alteration (up to 1m). Sub-vertical shear and extension fractures, and sub-horizontal shear fractures/zones dominate the NE side of the core complex. In all cases, sub-vertical fractures verge into or are truncated by low-angle fractures that dominate the top of the damage zone. These low-angle fractures have an antithetic dip to the detachment fault plane. Some sub-vertical fractures become curviplanar close to the fault, where they are folded into parallelism with the sub-horizontal fault surface in the direction of transport. These field data, corroborated by ongoing microstructural analyses, indicate fault activity at a low angle accommodated by a variety of deformation mechanisms dependent on lithology, timing, fluid flow, and fault morphology.

The variation of crustal structure along the Song Ma Shear Zone, Northern Vietnam

Science.gov (United States)

Su, Chien-Min; Wen, Strong; Tang, Chi-Chia; Yeh, Yu-Lien; Chen, Chau-Huei

2018-06-01

Northern Vietnam is divided into two regions by suture zone. The southwestern region belongs to the Indochina block, and the northeastern region is a portion of the South China block with distinct geological characteristics. From previous studies, the closing the Paleotethys led the collision between the Indochina and South China blocks, and this collision form the suture zone in the Middle Triassic. In the Tertiary, Indian and Eurasian plates started to collide, and this collision caused the extrusion of the Indochina block along the suture zone and a clockwise rotation. Metamorphic rocks associated with the subduction process have been found at the Song Ma Shear Zone (SMSZ) from geological surveys, which indicated that the SMSZ is a possible boundary between the South China and Indochina block. However, according to previous study, there is an argument of whether the SMSZ is a subduction zone of the South China and Indochina plates or not. In this study, we applied the H-κ and the common conversion point (CCP) stacking method using teleseismic converted waves recorded by a seismic broadband array to obtain the Moho depth, VP/VS ratio and the crustal structure along the SMSZ. The CCP results are further used to identify whether the fault extends through the entire crust or not. We have selected two profiles along the SMSZ and a profile across the SMSZ for imaging lateral variations of impedance from stacking. According to H-κ stacking results, crustal thickness vary from 26.0 to 29.3 km, and the average of VP/VS ratio is about 1.77. Finally, the CCP results also show the heterogeneity of crust among the SMSZ. These evidences might support that SMSZ is the suture zone between the South China and Indochina plates.

Effects of stitch density and stitch thread thickness on mode II delamination properties of Vectran stitched composites

KAUST Repository

Herwan, J.

2014-11-01

© Institute of Materials, Minerals and Mining 2014. Mode II delamination properties of Vectran stitched composites were investigated, and tabbed end notch flexural specimen testing was used to prevent premature failure. The effects of stitch density and stitch thread thickness were explored, and fibre compaction due to the stitching process was also verified. The results show that, in moderately stitched laminates (low stitch density), the improvement in GIIC was negligible. Crack bridging by the stitch threads at the crack zone were mostly compensated for the effect of fibre compaction, which reduced the GIIC values. Conversely, in densely stitched laminates (high stitch density), GIIC values were improved significantly (2·4 times higher than those of unstitched laminates). The effects of stitch thread thickness appeared to be negligible in moderately stitched laminates. For densely stitched laminates, thicker stitch thread (500 denier) possessed GIIC values that were 45·7% higher than thinner stitch thread (200 denier).

Effects of stitch density and stitch thread thickness on mode II delamination properties of Vectran stitched composites

KAUST Repository

Herwan, J.; Kondo, A.; Morooka, S.; Watanabe, N.

2014-01-01

© Institute of Materials, Minerals and Mining 2014. Mode II delamination properties of Vectran stitched composites were investigated, and tabbed end notch flexural specimen testing was used to prevent premature failure. The effects of stitch density and stitch thread thickness were explored, and fibre compaction due to the stitching process was also verified. The results show that, in moderately stitched laminates (low stitch density), the improvement in GIIC was negligible. Crack bridging by the stitch threads at the crack zone were mostly compensated for the effect of fibre compaction, which reduced the GIIC values. Conversely, in densely stitched laminates (high stitch density), GIIC values were improved significantly (2·4 times higher than those of unstitched laminates). The effects of stitch thread thickness appeared to be negligible in moderately stitched laminates. For densely stitched laminates, thicker stitch thread (500 denier) possessed GIIC values that were 45·7% higher than thinner stitch thread (200 denier).

Thick film hydrogen sensor

Science.gov (United States)

Hoffheins, Barbara S.; Lauf, Robert J.

1995-01-01

A thick film hydrogen sensor element includes an essentially inert, electrically-insulating substrate having deposited thereon a thick film metallization forming at least two resistors. The metallization is a sintered composition of Pd and a sinterable binder such as glass frit. An essentially inert, electrically insulating, hydrogen impermeable passivation layer covers at least one of the resistors.

Subsurface signature of North Anatolian Fault Zone and its relation with old sutures: New insight from receiver function analysis.

Science.gov (United States)

Özacar, Arda A.; Abgarmi, Bizhan

2017-04-01

The North Anatolian Fault Zone (NAFZ) is an active continental transform plate boundary that accommodates the westward extrusion of the Anatolian plate. The central segment of NAFZ displays northward convex surface trace which coincides partly with the Paleo-Tethyan suture formed during the early Cenozoic. The depth extent and detailed structure of the actively deforming crust along the NAF is still under much debate and processes responsible from rapid uplift are enigmatic. In this study, over five thousand high quality P receiver functions are computed using teleseismic earthquakes recorded by permanent stations of national agencies and temporary North Anatolian Fault Passive Seismic experiment (2005-2008). In order to map the crustal thickness and Vp/Vs variations accurately, the study area is divided into grids with 20 km spacing and along each grid line Moho phase and its multiples are picked through constructed common conversion point (CCP) profiles. According to our results, nature of discontinuities and crustal thickness display sharp changes across the main strand of NAFZ supporting a lithospheric scale faulting that offsets Moho discontinuity. In the southern block, crust is relatively thin in the west ( 35 km) and becomes thicker gradually towards east ( 40 km). In contrast, the northern block displays a strong lateral change in crustal thickness reaching up to 10 km across a narrow roughly N-S oriented zone which is interpreted as the subsurface signature of the ambiguous boundary between Istanbul Block and Pontides located further west at the surface.

Shyok Suture Zone, N Pakistan: late Mesozoic Tertiary evolution of a critical suture separating the oceanic Ladakh Arc from the Asian continental margin

Science.gov (United States)

Robertson, Alastair H. F.; Collins, Alan S.

2002-02-01

The Shyok Suture Zone (Northern Suture) of North Pakistan is an important Cretaceous-Tertiary suture separating the Asian continent (Karakoram) from the Cretaceous Kohistan-Ladakh oceanic arc to the south. In previously published interpretations, the Shyok Suture Zone marks either the site of subduction of a wide Tethyan ocean, or represents an Early Cretaceous intra-continental marginal basin along the southern margin of Asia. To shed light on alternative hypotheses, a sedimentological, structural and igneous geochemical study was made of a well-exposed traverse in North Pakistan, in the Skardu area (Baltistan). To the south of the Shyok Suture Zone in this area is the Ladakh Arc and its Late Cretaceous, mainly volcanogenic, sedimentary cover (Burje-La Formation). The Shyok Suture Zone extends northwards (ca. 30 km) to the late Tertiary Main Karakoram Thrust that transported Asian, mainly high-grade metamorphic rocks southwards over the suture zone. The Shyok Suture Zone is dominated by four contrasting units separated by thrusts, as follows: (1). The lowermost, Askore amphibolite, is mainly amphibolite facies meta-basites and turbiditic meta-sediments interpreted as early marginal basin rift products, or trapped Tethyan oceanic crust, metamorphosed during later arc rifting. (2). The overlying Pakora Formation is a very thick (ca. 7 km in outcrop) succession of greenschist facies volcaniclastic sandstones, redeposited limestones and subordinate basaltic-andesitic extrusives and flow breccias of at least partly Early Cretaceous age. The Pakora Formation lacks terrigenous continental detritus and is interpreted as a proximal base-of-slope apron related to rifting of the oceanic Ladakh Arc; (3). The Tectonic Melange (ocean ridge-type volcanics and recrystallised radiolarian cherts, interpreted as accreted oceanic crust. (4). The Bauma-Harel Group (structurally highest) is a thick succession (several km) of Ordovician and Carboniferous to Permian-Triassic, low

A ~400 ka supra-Milankovitch cycle in the Na, Mg, Pb, Ni, and Co records of a ferromanganese crust from the Vityaz fracture zone, central Indian ridge.

Digital Repository Service at National Institute of Oceanography (India)

Banerjee, R.; Gupta, S.M.; Miura, H.; Borole, D.V.

A approx. 400 ka (kilo years) supra-Milankovitch cycle, recorded in the sodium, magnesium, lead, nickel and cobalt contents of a 32mm thick ferromanganese crust from Vityaz fracture zone, central Indian ridge is reported here. To arrive...

Immediate provisionalization in the esthetic zone: 1-year interim results from a prospective single-cohort multicenter study evaluating 3.0-mm-diameter tapered implants.

Science.gov (United States)

Kolinski, Martin; Hess, Pablo; Leziy, Sonia; Friberg, Bertil; Bellucci, Gionata; Trisciuoglio, Davide; Wagner, Wilfried; Moergel, Maximilian; Pozzi, Alessandro; Wiltfang, Jörg; Behrens, Eleonore; Zechner, Werner; Vasak, Christoph; Weigl, Paul

2018-07-01

The aim of this interim analysis of a 5-year prospective multicenter study is to evaluate clinical and radiological performance of immediately provisionalized 3.0-mm-diameter tapered implants. Patients needing implant rehabilitation of maxillary lateral incisors or mandibular lateral and central incisors were treated with 3.0-mm-diameter implants placed in extraction or healed sites and immediately provisionalized. Clinical and radiographic examinations were performed at implant insertion, 6 months thereafter, and are ongoing. Marginal bone levels and changes, complications, the papilla, plaque, and bleeding indices, and the pink esthetic score (PES) were evaluated at each follow-up visit. Of 112 enrolled patients, 77 patients (91 implants) met the inclusion criteria. Seventy-one patients with 82 implants completed the 1-year follow-up. Three implants failed yielding a CSR of 96.7%. All failures occurred within the first 3 months after implant insertion. Marginal bone level changes from insertion to 6 months was - 0.57 ± 1.30 mm (n = 75) and from insertion to 12 months - 0.25 ± 1.38 mm (n = 72). Fifteen non-serious complications were recorded. Papilla index score and PES improved at the 1-year follow-up. Plaque formation and bleeding-on-probing showed no statistically significant differences between the 6-month and the 1-year visit. This 1-year analysis demonstrated high survival, stable bone levels, and healthy soft tissue with 3.0-mm-diameter implants. Narrow diameter implants are a safe and predictable treatment option in patients with limited bone volume and/or limited interdental space and eligible for immediate loading protocols.

Transport of elemental mercury in the unsaturated zone from a waste disposal site in an arid region

Science.gov (United States)

Walvoord, Michelle Ann; Andraski, Brian J.; Krabbenhoft, D.P.; Striegl, Robert G.

2008-01-01

Mercury contained in buried landfill waste may be released via upward emission to the atmosphere or downward leaching to groundwater. Data from the US Geological Survey’s Amargosa Desert Research Site (ADRS) in arid southwestern Nevada reveal another potential pathway of Hg release: long-distance (102 m) lateral migration of elemental Hg (Hg0) through the unsaturated zone. Gas collected from multiple depths from two instrumented boreholes that sample the entire 110-m unsaturated zone thickness and are located 100 and 160 m away from the closest waste burial trench exhibit gaseous Hg concentrations of up to 33 and 11 ng m−3, respectively. The vertical distribution of gaseous Hg in the borehole closest to the disposal site shows distinct subsurface peaks in concentration at depths of 1.5 and 24 m that cannot be explained by radial diffusive transport through a heterogeneous layered unsaturated zone. The inability of current models to explain gaseous Hg distribution at the ADRS highlights the need to advance the understanding of gas-phase contaminant transport in unsaturated zones to attain a comprehensive model of landfill Hg release.

Marginal bone loss evaluation around immediate non-occlusal microthreaded implants placed in fresh extraction sockets in the maxilla: a 3-year study.

Science.gov (United States)

Calvo-Guirado, José L; Gómez-Moreno, Gerardo; Aguilar-Salvatierra, Antonio; Guardia, Javier; Delgado-Ruiz, Rafael A; Romanos, Georgios E

2015-07-01

To evaluate marginal bone loss over 3 years around immediate microthreaded implants placed in the maxillary anterior/esthetic zone and immediately restored with single crowns. Seventy-one implants (with microthreads up to the platform--rough surface body and neck, internal connection and platform switching) were placed in fresh extraction sockets in the maxillary arches of 30 men and 23 women (mean age 37.85 ± 7.09 years, range 27-60). All subjects had at least 3 mm of soft tissue to allow the establishment of adequate biologic width and to reduce bone resorption. Each patient received a provisional restoration immediately after implant placement with slight occlusal contact. Mesial and distal bone height was evaluated using digital radiography on the day following implant placement (baseline) and after 1, 2, and 3 years. Primary stability was measured with resonance frequency analysis. No implants failed, resulting in a cumulative survival rate of 100% after 3 years. Marginal bone loss from implant collar to bone crest measured at baseline (peri-implant bone defect at the fresh extraction socket) and after 3 years was 0.86 mm ± 0.29 mm. Mesial and distal site crestal bone loss ranged from 3.42 mm ± 1.2 mm at baseline to 3.51 mm ± 1.5 mm after 3 years (P = 0.063) and from 3.38 mm ± 0.9 mm at baseline to 3.49 mm ± 0.9 mm after 3 years, respectively (P = 0.086). This prospective study found minimal marginal bone loss and a 100% implant survival rate over the 3-year follow-up for microthreaded immediate implants subjected to immediate non-occlusal loading. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Constraining the hydration of the subducting Nazca plate beneath Northern Chile using subduction zone guided waves

Science.gov (United States)

Garth, Tom; Rietbrock, Andreas

2017-09-01

Guided wave dispersion is observed from earthquakes at 180-280 km depth recorded at stations in the fore-arc of Northern Chile, where the 44 Ma Nazca plate subducts beneath South America. Characteristic P-wave dispersion is observed at several stations in the Chilean fore-arc with high frequency energy (>5 Hz) arriving up to 3 s after low frequency (accounted for if dipping low velocity fault zones are included within the subducting lithospheric mantle. A grid search over possible LVL and faults zone parameters (width, velocity contrast and separation distance) was carried out to constrain the best fitting model parameters. Our results imply that fault zone structures of 0.5-1.0 km thickness, and 5-10 km spacing, consistent with observations at the outer rise are present within the subducted slab at intermediate depths. We propose that these low velocity fault zone structures represent the hydrated structure within the lithospheric mantle. They may be formed initially by normal faults at the outer rise, which act as a pathway for fluids to penetrate the deeper slab due to the bending and unbending stresses within the subducting plate. Our observations suggest that the lithospheric mantle is 5-15% serpentinised, and therefore may transport approximately 13-42 Tg/Myr of water per meter of arc. The guided wave observations also suggest that a thin LVL (∼1 km thick) interpreted as un-eclogitised subducted oceanic crust persists to depths of at least 220 km. Comparison of the inferred seismic velocities with those predicted for various MORB assemblages suggest that this thin LVL may be accounted for by low velocity lawsonite-bearing assemblages, suggesting that some mineral-bound water within the oceanic crust may be transported well beyond the volcanic arc. While older subducting slabs may carry more water per metre of arc, approximately one third of the oceanic material subducted globally is of a similar age to the Nazca plate. This suggests that subducting oceanic

Thick-section weldments in 21-6-9 and 316LN stainless steel for fusion energy applications

International Nuclear Information System (INIS)

Alexander, D.J.; Goodwin, G.M.

1991-01-01

The Burning Plasma Experiment (BPX), formerly known as the Compact Ignition Tokomak, will be a major advance in the design of a fusion reactor. The successful construction of fusion reactors will require extensive welding of thick-section stainless steel plates. Severe service conditions will be experienced by the structure. Operating temperatures will range from room temperature (300 K) to liquid nitrogen temperature (77 K), and perhaps even lower. The structure will be highly stressed, and subject to sudden impact loads if plasma disruptions occur. This demands a combination of high strength and high toughness from the weldments. Significant portions of the welding will be done in the field, so preweld and postweld heat treatments will be difficult. The thick sections to be welded will require a high deposition rate process, and will result in significant residual stresses in the materials. Inspection of these thick sections in complex geometries will be very difficult. All of these constraints make it essential that the welding procedures and alloys be well understood, and the mechanical properties of the welds and their heat-affected zones must be adequately characterized. The candidate alloy for structural applications in the BPX such as the magnet cases was initially selected as 21-6-9 austenitic stainless steel, and later changed to 316LN stainless steel. This study examined several possible filler materials for thick-section (25 to 50 mm) weldments in these two materials. The tensile and Charpy V-notch properties were measured at room temperature and 77 K. The fracture toughness was measured for promising materials

Fault zone processes in mechanically layered mudrock and chalk

Science.gov (United States)

Ferrill, David A.; Evans, Mark A.; McGinnis, Ronald N.; Morris, Alan P.; Smart, Kevin J.; Wigginton, Sarah S.; Gulliver, Kirk D. H.; Lehrmann, Daniel; de Zoeten, Erich; Sickmann, Zach

2017-04-01

A 1.5 km long natural cliff outcrop of nearly horizontal Eagle Ford Formation in south Texas exposes northwest and southeast dipping normal faults with displacements of 0.01-7 m cutting mudrock, chalk, limestone, and volcanic ash. These faults provide analogs for both natural and hydraulically-induced deformation in the productive Eagle Ford Formation - a major unconventional oil and gas reservoir in south Texas, U.S.A. - and other mechanically layered hydrocarbon reservoirs. Fault dips are steep to vertical through chalk and limestone beds, and moderate through mudrock and clay-rich ash, resulting in refracted fault profiles. Steeply dipping fault segments contain rhombohedral calcite veins that cross the fault zone obliquely, parallel to shear segments in mudrock. The vertical dimensions of the calcite veins correspond to the thickness of offset competent beds with which they are contiguous, and the slip parallel dimension is proportional to fault displacement. Failure surface characteristics, including mixed tensile and shear segments, indicate hybrid failure in chalk and limestone, whereas shear failure predominates in mudrock and ash beds - these changes in failure mode contribute to variation in fault dip. Slip on the shear segments caused dilation of the steeper hybrid segments. Tabular sheets of calcite grew by repeated fault slip, dilation, and cementation. Fluid inclusion and stable isotope geochemistry analyses of fault zone cements indicate episodic reactivation at 1.4-4.2 km depths. The results of these analyses document a dramatic bed-scale lithologic control on fault zone architecture that is directly relevant to the development of porosity and permeability anisotropy along faults.

Origami-Inspired Folding of Thick, Rigid Panels

Science.gov (United States)

Trease, Brian P.; Thomson, Mark W.; Sigel, Deborah A.; Walkemeyer, Phillip E.; Zirbel, Shannon; Howell, Larry; Lang, Robert

2014-01-01

To achieve power of 250 kW or greater, a large compression ratio of stowed-to-deployed area is needed. Origami folding patterns were used to inspire the folding of a solar array to achieve synchronous deployment; however, origami models are generally created for near-zero-thickness material. Panel thickness is one of the main challenges of origami-inspired design. Three origami-inspired folding techniques (flasher, square twist, and map fold) were created with rigid panels and hinges. Hinge components are added to the model to enable folding of thick, rigid materials. Origami models are created assuming zero (or near zero) thickness. When a material with finite thickness is used, the panels are required to bend around an increasingly thick fold as they move away from the center of the model. The two approaches for dealing with material thickness are to use membrane hinges to connect the panels, or to add panel hinges, or hinges of the same thickness, at an appropriate width to enable folding.

Immediation (Cultures of Immediacy)

DEFF Research Database (Denmark)

Kacunko, Slavko

2018-01-01

with a complex interplay of social-, security-, science- and economy-related issues. The growing interest in immediation confirms its status as a new but as yet underestimated paradigm for the arts, sciences and humanities which calls for a future-focused inquiry into the cultures of immediacy. However...

Immediate effect of irradiation on microvasculature

International Nuclear Information System (INIS)

Krishnan, L.; Krishnan, E.C.; Jewell, W.R.

1988-01-01

The immediate effects of irradiation on microvasculature in muscle in an animal model are described in this paper. By using triple isotopes of 125 I, 131 I, and 22 Na, the transcapillary transfer of albumin from the vascular bed to the extravascular space is determined in terms of mg/g of tissue, after single doses of 2 to 14 Gy. These results reveal an increase in the extravascular albumin immediately after irradiation and suggest an instantaneous compromise in vascular permeability even after 2 Gy. This effect was apparently dose related

Cyclical Fault Permeability in the Lower Seismogenic Zone: Geological Evidence

Science.gov (United States)

Sibson, R. H.

2005-12-01

Syntectonic hydrothermal veining is widespread in ancient fault zones exhibiting mixed brittle-ductile behavior that are exhumed from subgreenschist to greenschist environments. The hydrothermal material (predominantly quartz ± carbonate) commonly occurs as fault-veins developed along principal slip surfaces, with textures recording intermittent deposition, sometimes in the form of repeated episodes of brecciation and recementation. Systematic sets of extension veins with histories of incremental dilation often occur in adjacent wallrocks. Conspicuous for their size and continuity among these fault-hosted vein systems are mesozonal Au-quartz lodes, which are most widespread in Archean granite-greenstone belts but also occur throughout the geological record. Most of these lode gold deposits developed at pressures of 1-5 kbar and temperatures of 200-450°C within the lower continental seismogenic zone. A notable characteristic is their vertical continuity: many `ribbon-texture' fault veins with thicknesses of the order of a meter extend over depth ranges approaching 2 km. The largest lodes are usually hosted by reverse or reverse- oblique fault zones with low finite displacement. Associated flat-lying extension veins in the wallrock may taper away from the shear zones over tens or hundreds of meters, and demonstrate repeated attainment of the ~lithostatic fluid overpressures needed for hydraulic extension fracturing. Where hosted by extensional-transtensional fault systems, lode systems tend to be less well developed. Mesozonal vein systems are inferred to be the product of extreme fault-valve behavior, whereby episodic accumulation of pore-fluid pressure to near-lithostatic values over the interseismic period leads to fault rupture, followed by postseismic discharge of substantial fluid volumes along the freshly permeable rupture zone inducing hydrothermal precipitation that seals the fracture permeability. Aqueous mineralizing fluids were generally low

Ridge expansion and immediate placement with piezosurgery and screw expanders in atrophic maxillary sites: two case reports.

Science.gov (United States)

Kelly, Andrew; Flanagan, Dennis

2013-02-01

Endosseous dental implants may require bone augmentation before implant placement. Herein is described an approach to edentulous ridge expansion with the use of piezosurgery and immediate placement of implants. This may allow for a shortened treatment time and the elimination of donor-site morbidity. Two cases are reported. This technique uses a piezoelectric device to cut the crestal and proximal facial cortices. Space is then created with motorized osteotomes to widen the split ridge. This technique allows for expansion of narrow, anatomically limiting, atrophic ridges, creating space for immediate implant placement. The facial and lingual cortices provide support with vital osteocytes for osteogenesis. The 2 patients presented had adequate bone height for implant placement but narrow edentulous ridges. In patient 1 at site #11, the ridge crest was 3.12 mm thick and was expanded to accept a 4.3 mm × 13 mm implant. The resulting ridge width was 8.88 mm, which was verified using cone beam computerized tomography (CBCT). In patient 2 at site #8 and site #9, the narrow ridge was expanded using the same technique to accept 2 adjacent 3.5 mm × 14 mm implants. The implants were restored to a functional and esthetic outcome.

Reviews and syntheses: on the roles trees play in building and plumbing the critical zone

Directory of Open Access Journals (Sweden)

S. L. Brantley

2017-11-01

Full Text Available Trees, the most successful biological power plants on earth, build and plumb the critical zone (CZ in ways that we do not yet understand. To encourage exploration of the character and implications of interactions between trees and soil in the CZ, we propose nine hypotheses that can be tested at diverse settings. The hypotheses are roughly divided into those about the architecture (building and those about the water (plumbing in the CZ, but the two functions are intertwined. Depending upon one's disciplinary background, many of the nine hypotheses listed below may appear obviously true or obviously false. (1 Tree roots can only physically penetrate and biogeochemically comminute the immobile substrate underlying mobile soil where that underlying substrate is fractured or pre-weathered. (2 In settings where the thickness of weathered material, H, is large, trees primarily shape the CZ through biogeochemical reactions within the rooting zone. (3 In forested uplands, the thickness of mobile soil, h, can evolve toward a steady state because of feedbacks related to root disruption and tree throw. (4 In settings where h ≪ H and the rates of uplift and erosion are low, the uptake of phosphorus into trees is buffered by the fine-grained fraction of the soil, and the ultimate source of this phosphorus is dust. (5 In settings of limited water availability, trees maintain the highest length density of functional roots at depths where water can be extracted over most of the growing season with the least amount of energy expenditure. (6 Trees grow the majority of their roots in the zone where the most growth-limiting resource is abundant, but they also grow roots at other depths to forage for other resources and to hydraulically redistribute those resources to depths where they can be taken up more efficiently. (7 Trees rely on matrix water in the unsaturated zone that at times may have an isotopic composition distinct from the gravity

Reviews and syntheses: on the roles trees play in building and plumbing the critical zone

Science.gov (United States)

Brantley, Susan L.; Eissenstat, David M.; Marshall, Jill A.; Godsey, Sarah E.; Balogh-Brunstad, Zsuzsanna; Karwan, Diana L.; Papuga, Shirley A.; Roering, Joshua; Dawson, Todd E.; Evaristo, Jaivime; Chadwick, Oliver; McDonnell, Jeffrey J.; Weathers, Kathleen C.

2017-11-01

Trees, the most successful biological power plants on earth, build and plumb the critical zone (CZ) in ways that we do not yet understand. To encourage exploration of the character and implications of interactions between trees and soil in the CZ, we propose nine hypotheses that can be tested at diverse settings. The hypotheses are roughly divided into those about the architecture (building) and those about the water (plumbing) in the CZ, but the two functions are intertwined. Depending upon one's disciplinary background, many of the nine hypotheses listed below may appear obviously true or obviously false. (1) Tree roots can only physically penetrate and biogeochemically comminute the immobile substrate underlying mobile soil where that underlying substrate is fractured or pre-weathered. (2) In settings where the thickness of weathered material, H, is large, trees primarily shape the CZ through biogeochemical reactions within the rooting zone. (3) In forested uplands, the thickness of mobile soil, h, can evolve toward a steady state because of feedbacks related to root disruption and tree throw. (4) In settings where h ≪ H and the rates of uplift and erosion are low, the uptake of phosphorus into trees is buffered by the fine-grained fraction of the soil, and the ultimate source of this phosphorus is dust. (5) In settings of limited water availability, trees maintain the highest length density of functional roots at depths where water can be extracted over most of the growing season with the least amount of energy expenditure. (6) Trees grow the majority of their roots in the zone where the most growth-limiting resource is abundant, but they also grow roots at other depths to forage for other resources and to hydraulically redistribute those resources to depths where they can be taken up more efficiently. (7) Trees rely on matrix water in the unsaturated zone that at times may have an isotopic composition distinct from the gravity-drained water that transits

Immediate placement of dental implants in the mandible

Directory of Open Access Journals (Sweden)

Gurkar Haraswarupa Puttaraju

2013-01-01

Full Text Available This case describes extraction of teeth in the mandibular arch, i.e., 41 42 43 44 45 51 52 53 54 55 56 57 58 (grade two mobility, followed by immediate placement of four dental implants (3i biomet, two in the 45 55 region and two dental implants in 12 21 region. A prefabricated provisional mandibular denture was immediately placed. The purpose of immediate placement was to aid the patient resume his professional duties the next day itself along with esthetic and functional comfort, psychological well-being and most importantly preserving the remaining tissue in a healthy condition.

Multiphasic modeling of charged solute transport across articular cartilage: Application of multi-zone finite-bath model.

Science.gov (United States)

Arbabi, Vahid; Pouran, Behdad; Weinans, Harrie; Zadpoor, Amir A

2016-06-14

Charged and uncharged solutes penetrate through cartilage to maintain the metabolic function of chondrocytes and to possibly restore or further breakdown the cartilage tissue in different stages of osteoarthritis. In this study the transport of charged solutes across the various zones of cartilage was quantified, taken into account the physicochemical interactions between the solute and the cartilage constituents. A multiphasic finite-bath finite element (FE) model was developed to simulate equine cartilage diffusion experiments that used a negatively charged contrast agent (ioxaglate) in combination with serial micro-computed tomography (micro-CT) to measure the diffusion. By comparing the FE model with the experimental data both the diffusion coefficient of ioxaglate and the fixed charge density (FCD) were obtained. In the multiphasic model, cartilage was divided into multiple (three) zones to help understand how diffusion coefficient and FCD vary across cartilage thickness. The direct effects of charged solute-FCD interaction on diffusion were investigated by comparing the diffusion coefficients derived from the multiphasic and biphasic-solute models. We found a relationship between the FCD obtained by the multiphasic model and ioxaglate partitioning obtained from micro-CT experiments. Using our multi-zone multiphasic model, diffusion coefficient of the superficial zone was up to ten-fold higher than that of the middle zone, while the FCD of the middle zone was up to almost two-fold higher than that of the superficial zone. In conclusion, the developed finite-bath multiphasic model provides us with a non-destructive method by which we could obtain both diffusion coefficient and FCD of different cartilage zones. The outcomes of the current work will also help understand how charge of the bath affects the diffusion of a charged molecule and also predict the diffusion behavior of a charged solute across articular cartilage. Copyright © 2016 Elsevier Ltd. All

Fatigue behavior of thick composite single lap joints

Energy Technology Data Exchange (ETDEWEB)

Tang, J.H.; Sridhar, I.; Srikanth, N. [Nanyang Technological Univ., Singapore (Singapore)

2012-07-01

In consideration of bondline thickness variability, in bonded joints where thick adherend is adopted, relative thick adhesive layer (2-5 mm) is preferable. This paper aims to give some insight in fatigue strength of adhesively bonded structures involving thick adherend coupled with thick adhesive layer. Single lap joints with nominal adherend thickness of 8 mm and two different nominal thicknesses (2.5 mm and 5.5 mm) were made and tested under fatigue loading. The failure mode exhibits always a tendency for interfacial initiation, followed by interlaminar separation. Fatigue strength for higher adhesive thickness is found to be lower. (Author)

Evaluation of danger zone in mesial root of mandibular first molar by cone beam computed tomography (CBCT)

International Nuclear Information System (INIS)

Chang, Yoo Rhee; Choi, Yong Suk; Choi, Gi Woon; Park, Sang Hyuk

2007-01-01

To examine the danger zone of medial root of mandibular first molar of patient without extraction using CBCT (cone-beam computed tomography) to avoid the risk of root perforation. 20 mandibular first molars without caries and restorations were collected. CT images were obtained by CBCT (PSR9000N T M, Asahi Roentgen Co., Japan), reformed and analyzed by V-work 5.0 (CyberMed Inc., Korea). Distance between canal orifice and furcation was measured. In cross sectional images at 3, 4 and 5 mm below the canal office, distal wall thickness of central part (C-D), medial wall thickness of mesiobuccal canal (MB-M) and mesial wall thickness of mesiolongual canal (ML-M) were measured. The mean distance between the canal orifice and the furcation of the roots is 2.40 mm. Distal wall is found to be thinner than medial wall. Mean dentinal wall thickness of distal wall is about 1 mm. The wall thickness is thinner as the distance from the canal orifice is farther. But significant differences and not noted between 4 mm and 5 mm in MB-D and C-D. MB-D is thinner than ML-D although the differences is not significant. The present study confirmed the anatomical weakness of distal surface of the coronol part of the medial roots of mandibular first molar by CBCT and provided an anatomical guide line of wall thickness during endodontic treatment

Fault zone hydrogeology

Science.gov (United States)

Bense, V. F.; Gleeson, T.; Loveless, S. E.; Bour, O.; Scibek, J.

2013-12-01

Deformation along faults in the shallow crust (research effort of structural geologists and hydrogeologists. However, we find that these disciplines often use different methods with little interaction between them. In this review, we document the current multi-disciplinary understanding of fault zone hydrogeology. We discuss surface- and subsurface observations from diverse rock types from unlithified and lithified clastic sediments through to carbonate, crystalline, and volcanic rocks. For each rock type, we evaluate geological deformation mechanisms, hydrogeologic observations and conceptual models of fault zone hydrogeology. Outcrop observations indicate that fault zones commonly have a permeability structure suggesting they should act as complex conduit-barrier systems in which along-fault flow is encouraged and across-fault flow is impeded. Hydrogeological observations of fault zones reported in the literature show a broad qualitative agreement with outcrop-based conceptual models of fault zone hydrogeology. Nevertheless, the specific impact of a particular fault permeability structure on fault zone hydrogeology can only be assessed when the hydrogeological context of the fault zone is considered and not from outcrop observations alone. To gain a more integrated, comprehensive understanding of fault zone hydrogeology, we foresee numerous synergistic opportunities and challenges for the discipline of structural geology and hydrogeology to co-evolve and address remaining challenges by co-locating study areas, sharing approaches and fusing data, developing conceptual models from hydrogeologic data, numerical modeling, and training interdisciplinary scientists.

Dual beam x-ray thickness gauge

International Nuclear Information System (INIS)

Allport, J.J.

1977-01-01

The apparatus and method for continuous measurement of thickness of a sheet at a rolling mill or the like without contacting the sheet are described. A system directing radiation through the sheet in two energy bands and providing a measure of change in composition of the material as it passes the thickness gauging station is included. A system providing for changing the absorption coefficient of the material in the thickness measurement as a function of the change in composition so that the measured thickness is substantially independent of variations in composition is described

Uncertainties in thick-target PIXE analysis

International Nuclear Information System (INIS)

Campbell, J.L.; Cookson, J.A.; Paul, H.

1983-01-01

Thick-target PIXE analysis insolves uncertainties arising from the calculation of thick-target X-ray production in addition to the usual PIXE uncertainties. The calculation demands knowledge of ionization cross-sections, stopping powers and photon attenuation coefficients. Information on these is reviewed critically and a computational method is used to estimate the uncertainties transmitted from this data base into results of thick-target PIXE analyses with reference to particular specimen types using beams of 2-3 MeV protons. A detailed assessment of the accuracy of thick-target PIXE is presented. (orig.)

Study on the ionization chamber for thickness measurement

International Nuclear Information System (INIS)

Xue Shili; Miao Qiangwen

1988-01-01

The principle, construction and performances of ionization chambers for measuring the thickness of metal and nonmetal materials are introduced. With them the thickness of thin materials (thickness ranging from 10 to 6000 g/m 2 ), the surface layer thickness of composed materials and the thickness of steel plate (thickness ranging from 0 to 32 kg/m 2 ) are measured effectively

Ice thickness profile surveying with ground penetrating radar at Artesonraju Glacier, Peru

Science.gov (United States)

Chisolm, Rachel; Rabatel, Antoine; McKinney, Daene; Condom, Thomas; Cochacin, Alejo; Davila Roller, Luzmilla

2014-05-01

survey was also undertaken to determine the radar velocity in the ice at Artesonraju Glacier. GPR measurements of Artesonraju Glacier show the ice thickness ranging from 20 meters at the terminus and gradually increasing to about 160 meters at the deepest part in the tongue of the glacier. After this point the bed slope begins to increase and the ice thickness decreases in the direction of the accumulation zone. A negative bed slope from the glacier terminus to the middle of the glacier tongue indicates that the conditions are favorable for the growth of a glacial lake with a potential maximum depth of about 60-80 m.

Effects of heat input on mechanical properties of metal inert gas welded 1.6 mm thick galvanized steel sheet

International Nuclear Information System (INIS)

Rafiqul, M I; Ishak, M; Rahman, M M

2012-01-01

It is usually a lot easier and less expensive to galvanize steel before it is welded into useful products. Galvanizing afterwards is almost impossible. In this research work, Galvanized Steel was welded by using the ER 308L stainless steel filler material. This work was done to find out an alternative way of welding and investigate the effects of heat input on the mechanical properties of butt welded joints of Galvanized Steel. A 13.7 kW maximum capacity MIG welding machine was used to join 1.6 mm thick sheet of galvanized steel with V groove and no gap between mm. Heat inputs was gradually increased from 21.06 to 25.07 joules/mm in this study. The result shows almost macro defects free welding and with increasing heat input the ultimate tensile strength and welding efficiency decrease. The Vickers hardness also decreases at HAZ with increasing heat input and for each individual specimen; hardness was lowest in heat affected zone (HAZ), intermediate in base metal and maximum in welded zone. The fracture for all specimens was in the heat affected zone while testing in the universal testing machine.

Effects of heat input on mechanical properties of metal inert gas welded 1.6 mm thick galvanized steel sheet

Science.gov (United States)

Rafiqul, M. I.; Ishak, M.; Rahman, M. M.

2012-09-01

It is usually a lot easier and less expensive to galvanize steel before it is welded into useful products. Galvanizing afterwards is almost impossible. In this research work, Galvanized Steel was welded by using the ER 308L stainless steel filler material. This work was done to find out an alternative way of welding and investigate the effects of heat input on the mechanical properties of butt welded joints of Galvanized Steel. A 13.7 kW maximum capacity MIG welding machine was used to join 1.6 mm thick sheet of galvanized steel with V groove and no gap between mm. Heat inputs was gradually increased from 21.06 to 25.07 joules/mm in this study. The result shows almost macro defects free welding and with increasing heat input the ultimate tensile strength and welding efficiency decrease. The Vickers hardness also decreases at HAZ with increasing heat input and for each individual specimen; hardness was lowest in heat affected zone (HAZ), intermediate in base metal and maximum in welded zone. The fracture for all specimens was in the heat affected zone while testing in the universal testing machine.

Modeling potential migration of petroleum hydrocarbons from a mixed-waste disposal site in the vadose zone

International Nuclear Information System (INIS)

Rawson, S.A.; Walton, J.C.; Baca, R.G.

1989-01-01

Environmental monitoring of a mixed-waste disposal site at the Idaho National Engineering Laboratory has confirmed release and migration into the vadose zone of: (1) chlorinated hydrocarbons in the vapor phase and (2) trace levels of certain transuranic elements. The finding has prompted an evaluation of the potential role of waste petroleum hydrocarbons in mediating or influencing contaminant migration from the disposal site. Disposal records indicate that a large volume of machine oil contaminated with transuranic isotopes was disposed at the site along with the chlorinated solvents and other radioactive wastes. A multiphase flow model was used to assess the possible extent of oil and vapor movement through the 177 m thick vadose zone. One dimensional simulations were performed to estimate the vertical distribution of the vapor phase, the aqueous phase, and immiscible free liquid as a function of time. The simulations indicate that the oil may migrate slowly through the vadose zone, to potentially significant depths. Calculated transport rates support the following ranking with regard to relative mobility: vapor phase > aqueous phase > free liquid. 21 refs., 7 figs., 2 tabs

Dynamics and mitigation of six pesticides in a "Wet" forest buffer zone.

Science.gov (United States)

Passeport, Elodie; Richard, Benjamin; Chaumont, Cédric; Margoum, Christelle; Liger, Lucie; Gril, Jean-Joël; Tournebize, Julien

2014-04-01

Pesticide pollution is one of the main current threats on water quality. This paper presents the potential and functioning principles of a "Wet" forest buffer zone for reducing concentrations and loads of glyphosate, isoproturon, metazachlor, azoxystrobin, epoxiconazole, and cyproconazole. A tracer injection experiment was conducted in the field in a forest buffer zone at Bray (France). A fine time-scale sampling enabled to illustrate that interactions between pesticides and forest buffer substrates (soil and organic-rich litter layer), had a retarding effect on molecule transfer. Low concentrations were observed for all pesticides at the forest buffer outlet thus demonstrating the efficiency of "Wet" forest buffer zone for pesticide dissipation. Pesticide masses injected in the forest buffer inlet directly determined concentration peaks observed at the outlet. Rapid and partially reversible adsorption was likely the major process affecting pesticide transfer for short retention times (a few hours to a few days). Remobilization of metazachlor, isoproturon, desmethylisoproturon, and AMPA was observed when non-contaminated water flows passed through the forest buffer. Our data suggest that pesticide sorption properties alone could not explain the complex reaction mechanisms that affected pesticide transfer in the forest buffer. Nevertheless, the thick layer of organic matter litter on the top of the forest soil was a key parameter, which enhanced partially reversible sorption of pesticide, thus retarded their transfer, decreased concentration peaks, and likely increased degradation of the pesticides. Consequently, to limit pesticide pollution transported by surface water, the use of already existing forest areas as buffer zones should be equally considered as the most commonly implemented grass buffer strips.

紫丁香叶柄离区IAA的免疫组织化学定位%Immunohistochemical Localization of IAA in the Leaf Abscission Zone of Syringa oblata

Institute of Scientific and Technical Information of China (English)

王幼群; 韩静; 林金星

2001-01-01

Freezing sections and immunogold-silver staining were employed tothe study on the localization of IAA in petioles of Syringa oblata Lind. At different stages of leaf abscission, the distribution patterns of the silver particles varied in different tissues. In the earlier period of abscission, there were many silver particles in the proximal and distal tissues, but only a few in the abscission zone. The high density of silver particles was found in the phloem of the petiole. The number of silver particles in the abscission zone increase immediately after the protective layer was formed and began to decrease along with the development of the abscission zone. The density of the silver particles became very low when abscission was completed. The formation of protective layer may be the demarcation line of the Stage Ⅰ and Stage Ⅱ during the development of the abscission zone.

Wildfire effects on vadose zone hydrology in forested boreal peatland microforms

Science.gov (United States)

Thompson, Dan K.; Waddington, James M.

2013-04-01

SummaryPeatland vulnerability to wildfire disturbance has been shown to vary as a function of hummock and hollow microforms and vadose zone hydrology, with low-lying hollow microforms most susceptible to deep combustion of peat. To better understand how this microform induced pattern of burning alters vadose water storage, pore-water pressure, and water table relationships, we examined a paired burned and unburned peatland in the boreal plain region of north central Alberta. Water table response to rain events increased significantly after wildfire, resulting in a more variable unsaturated zone thickness that was more responsive to smaller rain events. Water storage losses in the vadose zone occurred primarily at depths greater than 15 cm. Large peat surface water loss occurred in hummock microforms in the early spring due to the presence of unsaturated frozen peat at depth, likely a result of a vapour gradient from the unfrozen peat into the frozen peat underneath. During this period, the loss of water storage in the vadose zone satisfied up to 25% of daily evaporative demand, compared to only 3-5% during ice-free periods. A similar but less severe drying was observed late in summer, with burned hummocks the most vulnerable with high pore-water pressures. The enhanced surface drying observed is a precursor to high pore-water pressure conditions that inhibit Sphagnum regeneration. Our observations point to a paradox where the hummocks, being most resistant to combustion, are themselves most prone to high pore-water pressures following wildfire. The harsher hummock environment may contribute to the observed delay in post-fire Sphagnum regeneration in hummocks compared to hollows.

Thick Toenails

Science.gov (United States)

... in individuals with nail fungus (onychomycosis), psoriasis and hypothyroidism. Those who have problems with the thickness of their toenails should consult a foot and ankle surgeon for proper diagnosis and treatment. Find an ACFAS Physician Search Search Tools Find ...

Hip fracture and anthropometric variations: dominance among trochanteric soft tissue thickness, body height and body weight during sideways fall.

Science.gov (United States)

Majumder, Santanu; Roychowdhury, Amit; Pal, Subrata

2013-01-01

Hip fracture depends on various anthropometric parameters such as trochanteric soft tissue thickness, body height and body weight. The objective was to evaluate the responses to the variations in anthropometric parameters during sideways fall, and to identify the most dominant parameter among them. Seven finite element models were developed having anthropometric variations in trochanteric soft tissue thickness (5-26 mm), body height (1.70-1.88 m), and body weight (63-93.37 kg). These were simulated for sideways fall with ANSYS-LS-DYNA® code. Significant effect of trochanteric soft tissue thickness variation was found on 'normalized peak impact force with respect to the body weight' (p=0.004, r²=0.808) and strain ratio (p=0.083, r²=0.829). But, variation in body height was found to be less significant on normalized peak impact force (p=0.478, r²=0.105) and strain ratio (p=0.292, r²=0.217). Same was true for the variation in body weight on normalized peak impact force (p=0.075, r²=0.456) and strain ratio (p=0.857, r²=0.007). The risk factor for fracture was also well correlated to the strain ratio for the inter-trochanteric zone (pfractures are clinically observed to happen. Trochanteric soft tissue thickness was found likely to be the most dominant parameter over body height and body weight, signifying that a slimmer elderly person, taller or shorter, with less trochanteric soft tissue thickness should be advised to take preventive measures against hip fracture under sideways fall. © 2013.

doped ZnO thick film resistors

Indian Academy of Sciences (India)

The characterization and ethanol gas sensing properties of pure and doped ZnO thick films were investigated. Thick films of pure zinc oxide were prepared by the screen printing technique. Pure zinc oxide was almost insensitive to ethanol. Thick films of Al2O3 (1 wt%) doped ZnO were observed to be highly sensitive to ...

Radiofrequency ablation combined with transcatheter arterial embolisation in rabbit liver: investigation of the ablation zone according to the time interval between the two therapies.

Science.gov (United States)

Lee, I J; Kim, Y I; Kim, K W; Kim, D H; Ryoo, I; Lee, M W; Chung, J W

2012-11-01

This study was designed to evaluate the extent of the radiofrequency ablation zone in relation to the time interval between transcatheter arterial embolisation (TAE) and radiofrequency ablation (RFA) and, ultimately, to determine the optimal strategy of combining these two therapies for hepatocellular carcinoma. 15 rabbits were evenly divided into three groups: Group A was treated with RFA alone; Group B was treated with TAE immediately followed by RFA; and Group C was treated with TAE followed by RFA 5 days later. All animals underwent perfusion CT (PCT) scans immediately after RFA. Serum liver transaminases were measured to evaluate acute liver damage. Animals were euthanised for pathological analysis of ablated tissues 10 days after RFA. Non-parametric analyses were conducted to compare PCT indices, the RFA zone and liver transaminase levels among the three experimental groups. Group B showed a significantly larger ablation zone than the other two groups. Arterial liver perfusion and hepatic perfusion index represented well the perfusion decrease after TAE on PCT. Although Group B showed the most elevated liver transaminase levels at 1 day post RFA, the enzymes decreased to levels that were not different from the other groups at 10 days post-RFA. When combined TAE and RFA therapy is considered, TAE should be followed by RFA as quickly as possible, as it can be performed safely without serious hepatic deterioration, despite the short interval between the two procedures.

Immediate placement of endosseous implants into the extraction sockets.

Science.gov (United States)

Ebenezer, Vijay; Balakrishnan, K; Asir, R Vigil Dev; Sragunar, Banu

2015-04-01

Implant by definition "means any object or material, such as an alloplastic substance or other tissue, which is partial or completely inserted into the body for therapeutic, diagnostic, prosthetic, or experimental purpose." The placement of a dental implant in an extraction socket at the time of extraction or explantation is known as immediate implant placement whereas delayed placement of implant signifies the implant placement in edentulous areas where healing has completed with new bone formation after the loss of tooth/teeth. Recent idea goes by "why late when it can be done immediately." There are several advantages of immediate placement of implants, and lots of studies have been done. In this article, the advantages and disadvantages of immediate versus delayed placement of implants have been reviewed.

Ice thickness estimations based on multi-temporal glacier inventories - potential and challenges

Science.gov (United States)

Helfricht, Kay; Huss, Matthias; Otto, Jan-Christoph

2016-04-01

The ongoing glacier retreat exposes a large number of surface depressions in the former glacier bed that can be filled with water or act as sediment traps. This has already been observed at various sites in Austria and in other mountain areas worldwide. The formation of glacial lakes can constitute an important environmental and socio-economic impact on high mountain systems including water resource management, sediment delivery, natural hazards, energy production and tourism. In general, information on ice thickness distribution is the basis for simulating future glacier change. We used the approach proposed by Huss and Farinotti (2012) to model the ice thickness distribution and potential locations of subglacial depressions. The study is part of the FUTURELAKE project that seeks to model the formation of new glacier lakes and their possible future evolution in the Austria Alps. The required data on glacier extent, surface elevation and slope were taken from the Austrian Glacier Inventories GI1 from 1969, GI2 from 1998 and GI3 from2006 (Fischer et al., 2015). The different glacier outlines and surface elevations from the inventories enable us to evaluate (i) the robustness of the modelled bedrock depressions with respect to different glacier settings, (ii) the power of the model to simulate recently formed glacial lakes, (iii) the similarities in calculated ice thickness distributions across the inventories and (iv) the feasibility of simulating observed changes in ice thickness and glacier volume. In general, the modelled localization of large potential depressions was relatively stable using the observed glacier settings. A number of examples show that recently formed glacial lakes could be detected by the model based on previous glacier extents. The locations of maximum ice depths within different elevation zones appeared to be sensitive to changes in glacier width. However, observed ice thickness changes and, thus, volume changes between the inventories could

Maintenance of marginal bone support and soft tissue esthetics at immediately provisionalized OsseoSpeed implants placed into extraction sites: 2-year results.

Science.gov (United States)

Noelken, Robert; Neffe, Bettina Anna; Kunkel, Martin; Wagner, Wilfried

2014-02-01

Placement of implants into extraction sockets targets the maintenance of peri-implant hard and soft tissue structures and the support of a natural and esthetic contour. The main advantages of immediate implant insertion in comparison with delayed implant placement protocols are as follows: a reduced treatment time, less number of sessions, and, thus, the less invasive procedure. This study examines the clinical performance (survival rate, marginal bone levels and Pink Esthetic Score [PES]) of OsseoSpeed implants placed into extraction sockets with immediate provisionalization in the anterior maxilla after a follow-up of at least 12 months. Twenty patients received a total number of 37 OsseoSpeed implants which were immediately inserted into extraction sockets with or without facial bone deficiencies of various dimensions. A flapless procedure was applied, and the implants were immediately provisionalized with temporary crowns without occlusal contacts. Facial gaps between implant surface and facial bone or the previous contour of the alveolar process were grafted with autogenous bone chips. Implants in diameters 3.5, 4.0, 4.5, and 5.0 with lengths of 11-17 mm were used in the study. During the course of the study, interproximal marginal bone levels, the thickness of the facial bony wall, implant success rate according to the criteria established by Buser, and the PES were assessed per implant. One patient with three implants did not continue the study after prosthesis delivery, the remaining 34 implants were still in function at the final follow-up (survival rate: 100%). The mean follow-up period was 27 months (range, 12-40 months). Marginal bone height at the level of the implant shoulder averaged -0.1 ± 0.55 mm (range, -1.25 to 1.47 mm) at the final follow-up. The mean PES ratings were 11.3 ± 1.8 (range, 6-14) at the final follow-up. In 78% of the patients, the PES was preserved or even improved. Success rates, marginal bone levels, and esthetic results suggest

9 CFR 93.316 - Horses from Canada for immediate slaughter.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Horses from Canada for immediate...; REQUIREMENTS FOR MEANS OF CONVEYANCE AND SHIPPING CONTAINERS Horses Canada 16 § 93.316 Horses from Canada for immediate slaughter. Horses imported from Canada for immediate slaughter shall be consigned from the port of...

Immediate extinction promotes the return of fear.

Science.gov (United States)

Merz, Christian J; Hamacher-Dang, Tanja C; Wolf, Oliver T

2016-05-01

Accumulating evidence indicates that immediate extinction is less effective than delayed extinction in attenuating the return of fear. This line of fear conditioning research impacts the proposed onset of psychological interventions after threatening situations. In the present study, forty healthy men were investigated in a differential fear conditioning paradigm with fear acquisition in context A, extinction in context B, followed by retrieval testing in both contexts 24h later to test fear renewal. Differently coloured lights served as conditioned stimuli (CS): two CS (CS+) were paired with an electrical stimulation that served as unconditioned stimulus, the third CS was never paired (CS-). Extinction took place immediately after fear acquisition or 24h later. One CS+ was extinguished whereas the second CS+ remained unextinguished to control for different time intervals between fear acquisition and retrieval testing. Immediate extinction led to larger skin conductance responses during fear retrieval to both the extinguished and unextinguished CS relative to the CS-, indicating a stronger return of fear compared to delayed extinction. Taken together, immediate extinction is less potent than delayed extinction and is associated with a stronger renewal effect. Thus, the time-point of psychological interventions relative to the offset of threatening situations needs to be carefully considered to prevent relapses. Copyright © 2016 Elsevier Inc. All rights reserved.

A numerical study of the effects of a discrete fracture and an excavation damage zone on 129I transport through the geosphere

International Nuclear Information System (INIS)

Chan, T.; Scheier, N.W.; O'Connor, P.A.

1997-10-01

A numerical study has been conducted to investigate the effects of a discrete fracture and an excavation damage zone (EDZ) on groundwater mediated transport of I2 9 from a hypothetical nuclear fuel waste disposal vault through saturated, sparsely fractured plutonic rock to the biosphere. The reference disposal system simulated in the present work is based on the median value case of the postclosure assessment case study presented by AECL to support the Environmental Impact Statement (EIS) submitted to the Canadian Environmental Assessment Agency (CEAA). In particular, the reference geosphere is based mainly on hydrogeological characteristics at the site of AECL's Underground Research Laboratory in the Whiteshell Research Area, southeastern Manitoba. Several features not explicitly simulated in the EIS postclosure assessment case study are investigated in this study. These include the hypothetical possibility of a discrete fracture or a narrow fracture zone existing in the rock in the immediate vicinity of the disposal vault. This hypothetical fracture is modeled as a discrete fracture that connects or almost connects the vault to nearby fracture zone LD1. Simulations are performed using a combination of three-dimensional flow model and corresponding two-dimensional transport models, and the MOTIF finite-element code. It should be emphasized that the primary purpose of the present study it to investigate the relative importance of the various possible features in the rock in the immediate vicinity of the vault. Detailed numerical modelling of the effectiveness of various engineered barriers that could be used to mitigate any negative effects of such features is beyond the scope of this study

The impact of transcatheter aortic valve implantation on left ventricular performance and wall thickness – single-centre experience

Science.gov (United States)

Szymański, Piotr; Dąbrowski, Maciej; Zakrzewski, Dariusz; Michałek, Piotr; Orłowska-Baranowska, Ewa; El-Hassan, Kamal; Chmielak, Zbigniew; Witkowski, Adam; Hryniewiecki, Tomasz

2015-01-01

Introduction Transcatheter aortic valve implantation (TAVI) is a treatment alternative for the elderly population with severe symptomatic aortic stenosis (AS) at high risk for surgical aortic valve replacement (SAVR). Aim To assess the impact of TAVI on echocardiographic parameters of left ventricular (LV) performance and wall thickness in patients subjected to the procedure in a single-centre between 2009 and 2013. Material and methods The initial group consisted of 170 consecutive patients with severe AS unsuitable for SAVR. Logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) was 21.73 ±12.42% and mean age was 79.9 ±7.5 years. Results The TAVI was performed in 167 (98.2%) patients. Mean aortic gradient decreased significantly more rapidly after the procedure (from 58.6 ±16.7 mm Hg to 11.9 ±4.9 mm Hg, p < 0.001). The LV ejection fraction (LVEF) significantly increased in both short-term and long-term follow-up (57 ±14% vs. 59 ±13%, p < 0.001 and 56 ±14% vs. 60 ±12%, p < 0.001, respectively). Significant regression of interventricular septum diameter at end-diastole (IVSDD) and end-diastolic posterior wall thickness (EDPWth) was noted in early (15.0 ±2.4 mm vs. 14.5 ±2.3 mm, p < 0.001 and 12.7 ±2.1 mm vs. 12.4 ±1.9 mm, p < 0.028, respectively) and late post-TAVI period (15.1 ±2.5 mm to 14.3 ±2.5 mm, p < 0.001 and 12.8 ±2.0 mm to 12.4 ±1.9 mm, p < 0.007, respectively). Significant paravalvular leak (PL) was noted in 21 (13.1%) patients immediately after TAVI and in 13 (9.6%) patients in follow-up (p < 0.001). Moderate or severe mitral regurgitation (msMR) was seen in 24 (14.9%) patients from the initial group and in 19 (11.8%) patients after TAVI (p < 0.001). Conclusions The TAVI had an immediate beneficial effect on LVEF, LV walls thickness, and the incidence of msMR. The results of the procedure are comparable with those described in other centres. PMID:25848369

A method to measure the mean thickness and non-uniformity of non-uniform thin film by alpha-ray thickness gauge

International Nuclear Information System (INIS)

Miyahara, Hiroshi; Yoshida, Makoto; Watanabe, Tamaki

1977-01-01

The α-ray thickness gauge is used to measure non-destructively the thicknesses of thin films, and up to the present day, a thin film with uniform thickness is only taken up as the object of α-ray thickness gauge. When the thickness is determined from the displacement between the absorption curves in the presence and absence of thin film, the absorption curve must be displaced in parallel. When many uniform particles were dispersed as sample, the shape of the absorption curve was calculated as the sum of many absorption curves corresponding to the thin films with different thicknesses. By the comparison of the calculated and measured absorption curves, the number of particles, or the mean superficial density can be determined. This means the extension of thickness measurement from uniform to non-uniform films. Furthermore, these particle models being applied to non-uniform thin film, the possibility of measuring the mean thickness and non-uniformity was discussed. As the result, if the maximum difference of the thickness was more than 0.2 mg/cm 2 , the nonuniformity was considered to distinguish by the usual equipment. In this paper, an α-ray thickness gauge using the absorption curve method was treated, but one can apply this easily to an α-ray thickness gauge using α-ray energy spectra before and after the penetration of thin film. (auth.)

How accurate are estimates of glacier ice thickness? Results from ITMIX, the Ice Thickness Models Intercomparison eXperiment

DEFF Research Database (Denmark)

Farinotti, Daniel; Brinkerhoff, Douglas J.; Clarke, Garry K. C.

2017-01-01

Knowledge of the ice thickness distribution of glaciers and ice caps is an important prerequisite for many glaciological and hydrological investigations. A wealth of approaches has recently been presented for inferring ice thickness from characteristics of the surface. With the Ice Thickness Models...

Thick brane solutions

International Nuclear Information System (INIS)

Dzhunushaliev, Vladimir; Minamitsuji, Masato; Folomeev, Vladimir

2010-01-01

This paper gives a comprehensive review on thick brane solutions and related topics. Such models have attracted much attention from many aspects since the birth of the brane world scenario. In many works, it has been usually assumed that a brane is an infinitely thin object; however, in more general situations, one can no longer assume this. It is also widely considered that more fundamental theories such as string theory would have a minimal length scale. Many multidimensional field theories coupled to gravitation have exact solutions of gravitating topological defects, which can represent our brane world. The inclusion of brane thickness can realize a variety of possible brane world models. Given our understanding, the known solutions can be classified into topologically non-trivial solutions and trivial ones. The former class contains solutions of a single scalar (domain walls), multi-scalar, gauge-Higgs (vortices), Weyl gravity and so on. As an example of the latter class, we consider solutions of two interacting scalar fields. Approaches to obtain cosmological equations in the thick brane world are reviewed. Solutions with spatially extended branes (S-branes) and those with an extra time-like direction are also discussed.

33 CFR 165.169 - Safety and Security Zones: New York Marine Inspection Zone and Captain of the Port Zone.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety and Security Zones: New... Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY... Areas First Coast Guard District § 165.169 Safety and Security Zones: New York Marine Inspection Zone...

[Endoscopic full-thickness resection].

Science.gov (United States)

Meier, B; Schmidt, A; Caca, K

2016-08-01

Conventional endoscopic resection techniques such as endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) are powerful tools for the treatment of gastrointestinal (GI) neoplasms. However, those techniques are limited to the superficial layers of the GI wall (mucosa and submucosa). Lesions without lifting sign (usually arising from deeper layers) or lesions in difficult anatomic positions (appendix, diverticulum) are difficult - if not impossible - to resect using conventional techniques, due to the increased risk of complications. For larger lesions (>2 cm), ESD appears to be superior to the conventional techniques because of the en bloc resection, but the procedure is technically challenging, time consuming, and associated with complications even in experienced hands. Since the development of the over-the-scope clips (OTSC), complications like bleeding or perforation can be endoscopically better managed. In recent years, different endoscopic full-thickness resection techniques came to the focus of interventional endoscopy. Since September 2014, the full-thickness resection device (FTRD) has the CE marking in Europe for full-thickness resection in the lower GI tract. Technically the device is based on the OTSC system and combines OTSC application and snare polypectomy in one step. This study shows all full-thickness resection techniques currently available, but clearly focuses on the experience with the FTRD in the lower GI tract.

Technical Note: Cortical thickness and density estimation from clinical CT using a prior thickness-density relationship

Energy Technology Data Exchange (ETDEWEB)

Humbert, Ludovic, E-mail: ludohumberto@gmail.com [Galgo Medical, Barcelona 08036 (Spain); Hazrati Marangalou, Javad; Rietbergen, Bert van [Orthopaedic Biomechanics, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven 5600 MB (Netherlands); Río Barquero, Luis Miguel del [CETIR Centre Medic, Barcelona 08029 (Spain); Lenthe, G. Harry van [Biomechanics Section, KU Leuven–University of Leuven, Leuven 3001 (Belgium)

2016-04-15

Purpose: Cortical thickness and density are critical components in determining the strength of bony structures. Computed tomography (CT) is one possible modality for analyzing the cortex in 3D. In this paper, a model-based approach for measuring the cortical bone thickness and density from clinical CT images is proposed. Methods: Density variations across the cortex were modeled as a function of the cortical thickness and density, location of the cortex, density of surrounding tissues, and imaging blur. High resolution micro-CT data of cadaver proximal femurs were analyzed to determine a relationship between cortical thickness and density. This thickness-density relationship was used as prior information to be incorporated in the model to obtain accurate measurements of cortical thickness and density from clinical CT volumes. The method was validated using micro-CT scans of 23 cadaver proximal femurs. Simulated clinical CT images with different voxel sizes were generated from the micro-CT data. Cortical thickness and density were estimated from the simulated images using the proposed method and compared with measurements obtained using the micro-CT images to evaluate the effect of voxel size on the accuracy of the method. Then, 19 of the 23 specimens were imaged using a clinical CT scanner. Cortical thickness and density were estimated from the clinical CT images using the proposed method and compared with the micro-CT measurements. Finally, a case-control study including 20 patients with osteoporosis and 20 age-matched controls with normal bone density was performed to evaluate the proposed method in a clinical context. Results: Cortical thickness (density) estimation errors were 0.07 ± 0.19 mm (−18 ± 92 mg/cm{sup 3}) using the simulated clinical CT volumes with the smallest voxel size (0.33 × 0.33 × 0.5 mm{sup 3}), and 0.10 ± 0.24 mm (−10 ± 115 mg/cm{sup 3}) using the volumes with the largest voxel size (1.0 × 1.0 × 3.0 mm{sup 3}). A trend for the

Technical Note: Cortical thickness and density estimation from clinical CT using a prior thickness-density relationship

International Nuclear Information System (INIS)

Humbert, Ludovic; Hazrati Marangalou, Javad; Rietbergen, Bert van; Río Barquero, Luis Miguel del; Lenthe, G. Harry van

2016-01-01

Purpose: Cortical thickness and density are critical components in determining the strength of bony structures. Computed tomography (CT) is one possible modality for analyzing the cortex in 3D. In this paper, a model-based approach for measuring the cortical bone thickness and density from clinical CT images is proposed. Methods: Density variations across the cortex were modeled as a function of the cortical thickness and density, location of the cortex, density of surrounding tissues, and imaging blur. High resolution micro-CT data of cadaver proximal femurs were analyzed to determine a relationship between cortical thickness and density. This thickness-density relationship was used as prior information to be incorporated in the model to obtain accurate measurements of cortical thickness and density from clinical CT volumes. The method was validated using micro-CT scans of 23 cadaver proximal femurs. Simulated clinical CT images with different voxel sizes were generated from the micro-CT data. Cortical thickness and density were estimated from the simulated images using the proposed method and compared with measurements obtained using the micro-CT images to evaluate the effect of voxel size on the accuracy of the method. Then, 19 of the 23 specimens were imaged using a clinical CT scanner. Cortical thickness and density were estimated from the clinical CT images using the proposed method and compared with the micro-CT measurements. Finally, a case-control study including 20 patients with osteoporosis and 20 age-matched controls with normal bone density was performed to evaluate the proposed method in a clinical context. Results: Cortical thickness (density) estimation errors were 0.07 ± 0.19 mm (−18 ± 92 mg/cm"3) using the simulated clinical CT volumes with the smallest voxel size (0.33 × 0.33 × 0.5 mm"3), and 0.10 ± 0.24 mm (−10 ± 115 mg/cm"3) using the volumes with the largest voxel size (1.0 × 1.0 × 3.0 mm"3). A trend for the cortical thickness and

Optimum target thickness for polarimeters

International Nuclear Information System (INIS)

Sitnik, I.M.

2003-01-01

Polarimeters with thick targets are a tool to measure the proton polarization. But the question about the optimum target thickness is still the subject of discussion. An attempt to calculate the most common parameters concerning this problem, in a few GeV region, is made

33 CFR 165.814 - Security Zones; Captain of the Port Houston-Galveston Zone.

Science.gov (United States)

2010-07-01

... Port Houston-Galveston Zone. 165.814 Section 165.814 Navigation and Navigable Waters COAST GUARD... § 165.814 Security Zones; Captain of the Port Houston-Galveston Zone. (a) Location. The following areas are designated as security zones: (1) Houston, Texas. The Houston Ship Channel and all associated...

Immediate placement of endosseous implants into the extraction sockets

Directory of Open Access Journals (Sweden)

Vijay Ebenezer

2015-01-01

Full Text Available Implant by definition "means any object or material, such as an alloplastic substance or other tissue, which is partial or completely inserted into the body for therapeutic, diagnostic, prosthetic, or experimental purpose." The placement of a dental implant in an extraction socket at the time of extraction or explantation is known as immediate implant placement whereas delayed placement of implant signifies the implant placement in edentulous areas where healing has completed with new bone formation after the loss of tooth/teeth. Recent idea goes by "why late when it can be done immediately." There are several advantages of immediate placement of implants, and lots of studies have been done. In this article, the advantages and disadvantages of immediate versus delayed placement of implants have been reviewed.

Hydrogeology of the unsaturated zone, Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Montazer, P.; Wilson, W.E.

1985-01-01

The unsaturated volcanic tuff beneath Yucca Mountain, Nevada, is being evaluated by the US Department of Energy as a host rock for a potential mined geologic repository for high-level radioactive waste. Assessment of site suitability needs an efficient and focused investigative program. A conceptual hydrogeologic model that simulates the flow of fluids through the unsaturated zone at Yucca Mountain was developed to guide the program and to provide a basis for preliminary assessment of site suitability. The study was made as part of the Nevada Nuclear Waste Storage Investigations Project of the US Department of Energy. Thickness of the unsaturated zone is about 1640 to 2460 feet (500 to 750 meters). Based on physical properties, the rocks in the unsaturated zone are grouped for the purpose of this paper into five informal hydrogeologic units. From top to bottom these units are: Tiva Canyon welded unit, Paintbrush nonwelded unit. Topopah Spring welded unit, Calico Hills nonwelded unit, and Crater Flat unit. Welded units have a mean fracture density of 8 to 40 fractures per unit cubic meter, mean matrix porosities of 12 to 23%, matrix hydraulic conductivities with geometric means ranging from 6.5 x 10 -6 to 9.8 x 10 -6 foot per day (2 x 10 -6 to 3 x 10 -6 meter per day), and bulk hydraulic conductivities of 0.33 to 33 feet per day (0.1 to 10 meters per day). The nonwelded units have a mean fracture density of 1 to 3 fractures per unit cubic meter, mean matrix porosities of 31 to 46%, and saturated hydraulic conductivities with geometric means ranging from 2.6 x 10 -5 to 2.9 x 10 -2 foot per day (8 x 10 -6 to 9 x 10 -3 meter per day). 15 refs., 4 figs., 1 tab

Investigating point zero: The artificial catchment 'Chicken Creek' as an observatory to study critical zone structures and processes of the critical zone in an initial ecosystem

Science.gov (United States)

Hüttl, Reinhard F.; Gerwin, Werner

2010-05-01

Recently, earth surface structures reaching from vegetation to the groundwater in the near underground have been termed "critical zone". This zone is "critical" to supporting life on Earth and, thus, the understanding of processes within this zone is of great importance in environmental sciences. Investigating the critical zone requires interdisciplinary and integrative research approaches across the fields of geomorphology, ecology, biology, soil science, hydrology and environmental modeling. A central motivation of the critical zone concept is the need for moving beyond traditional disciplinary boundaries to a more holistic and integrated study of the Earth surface system. However, the critical zone is characterized by complex interactions between abiotic and biotic structures and processes which need to be analyzed for improving our understanding of ecosystem functioning as well as of ecosystem development. To gain a better understanding of these fundamental questions it might be helpful to look at initial ecosystems, i.e. at ecosystems in the initial phase of development. It can be hypothesized that the complexity of a very young ecosystem is lower compared to mature systems and, therefore, structure-process interactions might become more obvious at early than at later stages of development. In this context, an artificial watershed was constructed with well known boundary conditions to investigate the initial ecosystem phase. The catchment ‘Chicken Creek' in Lusatia (Germany; 150 km SE from Berlin) has an area of 6 ha. It was set up with a layer of post-glacial sandy sediments overlying an aquiclude made of clay at the base. These hydrological starting conditions allowed for the formation of a groundwater body within the sandy layer of the experimental catchment. Further, after completion of the construction works in September 2005 the site was left to natural succession and no measures like planting or fertilization were carried out. As the initial phase of

Identification of Zones and Areal Extent of Weathered Crystalline Basement in the Archean-Lower Proterozoic Crust of the South Tatar Arch

Directory of Open Access Journals (Sweden)

N.B. Amelchenko

2017-08-01

Full Text Available Based on the data of geophysical surveys and deep drilling the depth to the crystalline basement and its weathered upper layer at the eastern flank of the South Tartar Arch varies from 1650 to 2500 m. Against the ongoing depletion of hydrocarbon reserves in the Paleozoic reservoirs of the region the basement becomes a promising exploration target. However the study of its architecture, composition and areal extent is largely hindered by so far very limited coring in this interval. In previous research correlation of core data and wireline logs was used for petrophysical characterization and identification of zones in a vertical profile of the upper weathered layer of the basement in the deep parametric test wells 50 Novournyak and 2000 Tyimazy with most complete core recovery. These characterization criteria have been utilized for analysis of 750 deep wells drilled in Bashkortostan within the South Tatar Arch which is bounded in the south by the Serafimovsko-Baltaevskiy Graben. In 340 wells based on wireline and production logs the upper weathered layer of the basement revealed certain distinct features of vertical zonation. The analysis resulted in thickness maps for Zone B and combined thickness maps for Zones B + C where the weathered basement is characterized by two morphological types – linear-areal and linear-fractured. The findings support the initial assumption that the obtained petrophysical characteristics may be applied to identify the weathered crystalline basement in wells with no core.

Microstructure and properties of thick nanocomposite TiN/Si{sub 3}N{sub 4} coatings on Vanadis 23 HS steel

Energy Technology Data Exchange (ETDEWEB)

Moskalewicz, Tomasz; Czyrska-Filemonowicz, Aleksandra [AGH Univ. of Science and Technology, Faculty of Metals Engineering and Industrial Computer Science, Krakow (Poland); Zimowski, Slawomir [AGH Univ. of Science and Technology, Faculty of Mechanical Engineering and Robotics, Krakow (Poland); Wendler, Bogdan; Progalskiy, Ivan [Lodz Univ. of Technology (Poland). Inst. of Materials Science and Engineering

2015-07-15

The microstructure and selected micro-mechanical properties of a 13.4 μm thick nanocomposite TiN/Si{sub 3}N{sub 4} coating deposited onto Vanadis 23 HS steel by a new gas pulsed magnetron sputtering technique were investigated. Scanning and transmission electron microscopy were employed to investigate the detailed microstructure of the coating. It was found that the coating exhibited a fully nanocrystalline structure and was composed of two zones: the outer zone with columnar structure and the inner one with equiaxed, fine columnar structure. Both zones consisted mainly of the δ-TiN nanocrystallites with a small amount of α-Si{sub 3}N{sub 4} and β-Si{sub 3}N{sub 4}. In order to increase coating adhesion to the substrate, a graded intermediate layer consisting of three different phases (pure Cr, CrN and Cr2N) was applied. The hardness of the as-deposited TiN/Si{sub 3}N{sub 4} coating was equal to 48 GPa, whereas it was equal to 40 GPa after annealing. The coatings exhibited very good adhesion to the underlying steel substrate.

Tackling the Challenge of Deep Vadose Zone Remediation at the Hanford Site

Science.gov (United States)

Morse, J. G.; Wellman, D. M.; Gephart, R.

2010-12-01

The Central Plateau of the Hanford Site in Washington State contains some 800 waste disposal sites where 1.7 trillion liters of contaminated water was once discharged into the subsurface. Most of these sites received liquids from the chemical reprocessing of spent uranium fuel to recover plutonium. In addition, 67 single shell tanks have leaked or are suspected to have leaked 3.8 million liters of high alkali and aluminate rich cesium-contaminated liquids into the sediment. Today, this inventory of subsurface contamination contains an estimated 550,000 curies of radioactivity and 150 million kg (165,000 tons) of metals and hazardous chemicals. Radionuclides range from mobile 99Tc to more immobilized 137Cs, 241Am, uranium, and plutonium. A significant fraction of these contaminants likely remain within the deep vadose zone. Plumes of groundwater containing tritium, nitrate, 129I and other contaminants have migrated through the vadose zone and now extend outward from the Central Plateau to the Columbia River. During most of Hanford Site history, subsurface studies focused on groundwater monitoring and characterization to support waste management decisions. Deep vadose zone studies were not a priority because waste practices relied upon that zone to buffer contaminant releases into the underlying aquifer. Remediation of the deep vadose zone is now central to Hanford Site cleanup because these sediments can provide an ongoing source of contamination to the aquifer and therefore to the Columbia River. However, characterization and remediation of the deep vadose zone pose some unique challenges. These include sediment thickness; contaminant depth; coupled geohydrologic, geochemical, and microbial processes controlling contaminant spread; limited availability and effectiveness of traditional characterization tools and cleanup remedies; and predicting contaminant behavior and remediation performance over long time periods and across molecular to field scales. The U

Three-dimensional characterization of microporosity and permeability in fault zones hosted in heterolithic succession

Science.gov (United States)

Riegel, H. B.; Zambrano, M.; Jablonska, D.; Emanuele, T.; Agosta, F.; Mattioni, L.; Rustichelli, A.

2017-12-01

The hydraulic properties of fault zones depend upon the individual contributions of the damage zone and the fault core. In the case of the damage zone, it is generally characterized by means of fracture analysis and modelling implementing multiple approaches, for instance the discrete fracture network model, the continuum model, and the channel network model. Conversely, the fault core is more difficult to characterize because it is normally composed of fine grain material generated by friction and wear. If the dimensions of the fault core allows it, the porosity and permeability are normally studied by means of laboratory analysis or in the other case by two dimensional microporosity analysis and in situ measurements of permeability (e.g. micro-permeameter). In this study, a combined approach consisting of fracture modeling, three-dimensional microporosity analysis, and computational fluid dynamics was applied to characterize the hydraulic properties of fault zones. The studied fault zones crosscut a well-cemented heterolithic succession (sandstone and mudstones) and may vary in terms of fault core thickness and composition, fracture properties, kinematics (normal or strike-slip), and displacement. These characteristics produce various splay and fault core behavior. The alternation of sandstone and mudstone layers is responsible for the concurrent occurrence of brittle (fractures) and ductile (clay smearing) deformation. When these alternating layers are faulted, they produce corresponding fault cores which act as conduits or barriers for fluid migration. When analyzing damage zones, accurate field and data acquisition and stochastic modeling was used to determine the hydraulic properties of the rock volume, in relation to the surrounding, undamaged host rock. In the fault cores, the three-dimensional pore network quantitative analysis based on X-ray microtomography images includes porosity, pore connectivity, and specific surface area. In addition, images were

New Au-U deposit type in the weathering crust in tectonicmetasomatite zones of Pre-Cambrian shields

International Nuclear Information System (INIS)

Tarkhanov, A.

2014-01-01

Au-U mineralization is widely distributed in the tectonic-metasomatite zones of Pre-Cambrian shields (Aldan Shield, Ukraine Shield and others). The industrial ores are located only in several areas at depths of more than 150-300 m. Uranium mineralization is represented by uranotitnates and the gold mineralization by auriferous pyrite. The zone of weathering is present to the depth of 100-150 m. The feldspars are replaced by the clay minerals, carbonates are dissovled, sulfides are oxidized and the secondary minerals of uranium replace uranotitanates.The golden mineralization in the envelope of weathering is represented by the fine-grained native gold. The particle size is 40-50 nm. Uranium mineralization is in the form of relict brannerite, tuyamunite, torbernite, carnotite. The gold content is 1-2 g/t, and uranium content 0.01- 0.05% U. Ore bodies of gold and uranium are located inside the tectonic-metasomatite zones. The zones of maximum concentration of these metals may not coincide. The gold ore bodies have the length of hundreds meters and a thickness of 1-5 m. The vertical extent of the secondary Au-U mineralization is 100-150 m. 20 laboratory samples of ore from the weathered zone were tested by the method of heap leaching. The first stage is the uranium leach by diluted sulfuric acid. The second stage is the cyanation of gold and silver. The experimental data indicates leach rate of uranium 75%, gold 80-97%, silver 50-60%. Gold resources in the continous zone is estimated to be 80 t. Gold resources of the several other zones inside the area of 100 km 2 are estimated as 220 t. The heap leach process can be used for profitable development of the low-grade deposits. This method helps to increase the resources of gold and uranium. (author)

Standard practice for ultrasonic testing of the Weld Zone of welded pipe and tubing

CERN Document Server

American Society for Testing and Materials. Philadelphia

2010-01-01

1.1 This practice describes general ultrasonic testing procedures for the detection of discontinuities in the weld and adjacent heat affected zones of welded pipe and tubing by scanning with relative motion between the search unit and pipe or tube. When contact or unfocused immersion search units are employed, this practice is intended for tubular products having specified outside diameters ≥2 in. (≥50 mm) and specified wall thicknesses of 1/8to 11/16 in. (3 to 27 mm). When properly focused immersion search units are employed, this practice may also be applied to material of smaller diameter and thinner wall. Note 1—When contact or unfocused immersion search units are used, precautions should be exercised when examining pipes or tubes near the lower specified limits. Certain combinations of search unit size, frequency, thin–wall thicknesses, and small diameters could cause generation of unwanted sound waves that may produce erroneous examination results. 1.2 All surfaces of material to be examined in ...

Monitoring production target thickness

International Nuclear Information System (INIS)

Oothoudt, M.A.

1993-01-01

Pion and muon production targets at the Clinton P. Anderson Meson Physics Facility consist of rotating graphite wheels. The previous target thickness monitoring Procedure scanned the target across a reduced intensity beam to determine beam center. The fractional loss in current across the centered target gave a measure of target thickness. This procedure, however, required interruption of beam delivery to experiments and frequently indicated a different fractional loss than at normal beam currents. The new monitoring Procedure compares integrated ups and downs toroid current monitor readings. The current monitors are read once per minute and the integral of readings are logged once per eight-hour shift. Changes in the upstream to downstream fractional difference provide a nonintrusive continuous measurement of target thickness under nominal operational conditions. Target scans are now done only when new targets are installed or when unexplained changes in the current monitor data are observed

A thick placenta: a predictor of adverse pregnancy outcomes.

Science.gov (United States)

Miwa, Ichiro; Sase, Masakatsu; Torii, Mayumi; Sanai, Hiromi; Nakamura, Yasuhiko; Ueda, Kazuyuki

2014-01-01

The aim of this study is to evaluate the efficacy of an ultrasonographic measurement of placental thickness and the correlation of a thick placenta with adverse perinatal outcome. Placental thickness was measured in single gravidas, 16 to 40 weeks of gestation, between 2005 and 2009. Placentas were considered to be thick if their measured thickness were above the 95th percentile for gestational age. The incidence of thick placentas was 4.3% (138/3,183). Perinatal morbidity and neonatal conditions were worse in cases with thick placenta rather than without thick placenta. Ultrasonographic measurement of placental thickness is a simple method to estimate placental size. Thick placenta may be a useful predictor of adverse pregnancy outcomes.

A planar conducting microstructure to guide and confine magnetic beads to a sensing zone

KAUST Repository

Gooneratne, Chinthaka Pasan

2011-08-01

A novel planar conducting microstructure is proposed to transport and confine magnetic micro/nano beads to a sensing zone. Manipulation and concentration of magnetic beads are achieved by employing square-shaped conducting micro-loops, with a few hundred nano-meters in thickness, arranged in a unique fashion. These microstructures are designed to produce high magnetic field gradients which are directly proportional to the force applied to manipulate the magnetic beads. Furthermore, the size of the microstructures allows greater maneuverability and control of magnetic beads than what could be achieved by permanent magnets. The aim of the microstructures is to guide magnetic beads from a large area and confine them to a smaller area where for example quantification would take place. Experiments were performed with different concentrations of 2 μm diameter magnetic beads. Experimental results showed that magnetic beads could be successfully guided and confined to the sensing zone. © 2011 Elsevier B.V. All rights reserved.

Structural setting and magnetic properties of pseudotachylyte in a deep crustal shear zone, western Canadian shield

Science.gov (United States)

Orlandini, O. F.; Mahan, K. H.; Brown, L. L.; Regan, S.; Williams, M. L.

2012-12-01

Seismic slip commonly produces pseudotachylytes, a glassy vein-filling substance that is typically interpreted as either a frictional melt or an ultra-triturated cataclasite. In either form, pseudotachylytes are commonly magnetite enriched, even in magnetite-free host rocks, and therefore are potentially useful as high fidelity recorders of natural magnetic fields at the time of slip in a wide array of lithologies. Pseudotachylytes generally have high magnetic susceptibility and thus should preserve the dominant field present as the material passes the Curie temperatures of magnetic minerals, primarily magnetite. Two potential sources have been proposed for the dominant magnetic field recorded: the earth's magnetic field at the time of slip or the temporary and orders of magnitude more intense field created by the presence of coseismic currents along the failure plane. Pseudotachylytes of the Cora Lake shear zone (CLsz) in the Athabasca Granulite Terrain, western Canadian shield, are consistently hosted in high strain ultramylonitic orthogneiss. Sinistral and extensional oblique-slip in the CLsz occurred at high-pressure granulite-grade conditions of ~1.0 GPa and >800°C and may have persisted to somewhat lower P-T conditions (~0.8 GPa, 700 °C) during ductile deformation. Pseudotachylyte-bearing slip surfaces have sinistral offset, matching the larger shear zone, and clasts of wall rock in the more brecciated veins display field evidence for ductile shear along the same plane prior to brittle failure. The presence of undeformed pseudotachylyte in kinematically compatible fracture arrays localized in ultramylonite indicates that brittle failure may have occurred in the waning stages of shear zone activity and at similar deep crustal conditions. Field-documented occurrences of pseudotachylyte include 2 cm-thick veins that run subparallel to mylonitic foliation and contain small flow-aligned clasts and large, heavily brecciated foliation-crosscutting zones up to

Influence of Thickness on Ethanol Sensing Characteristics of Doctor-bladed Thick Film from Flame-made ZnO Nanoparticles

Directory of Open Access Journals (Sweden)

Sukon Phanichphant

2007-02-01

Full Text Available ZnO nanoparticles were produced by flame spray pyrolysis (FSP using zincnaphthenate as a precursor dissolved in toluene/acetonitrile (80/20 vol%. The particleproperties were analyzed by XRD, BET, and HR-TEM. The sensing films were produced bymixing the particles into an organic paste composed of terpineol and ethyl cellulose as avehicle binder and were fabricated by doctor-blade technique with various thicknesses (5,10, 15 μm. The morphology of the sensing films was analyzed by SEM and EDS analyses.The gas sensing characteristics to ethanol (25-250 ppm were evaluated as a function of filmthickness at 400°C in dry air. The relationship between thickness and ethanol sensingcharacteristics of ZnO thick film on Al2O3 substrate interdigitated with Au electrodes wereinvestigated. The effects of film thickness, as well as the cracking phenomenon, though,many cracks were observed for thicker sensing films. Crack widths increased withincreasing film thickness. The film thickness, cracking and ethanol concentration havesignificant effect on the sensing characteristics. The sensing characteristics with variousthicknesses were compared, showing the tendency of the sensitivity to ethanol decreasedwith increasing film thickness and response time. The relationship between gas sensingproperties and film thickness was discussed on the basis of diffusively and reactivity of thegases inside the oxide films. The thinnest sensing film (5 μm showed the highest sensitivityand the fastest response time (within seconds.

Petrology and geochemistry at the Lower zone-Middle zone transition of the Panzhihua intrusion, SW China: Implications for differentiation and oxide ore genesis

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Kwan-Nang Pang

2013-09-01

Full Text Available A sequence of gabbros showing isotropic, layered and fine-grained textures is exposed in the Nalaqing mine at the southern tip of the ∼260 Ma Panzhihua intrusion, SW China. The field relations, structure, texture and mineralogy of the rocks indicate that the sequence represents the transition between the Lower zone and Middle zone of the intrusion. Isotropic gabbros characteristic of the Lower zone pass upward to layered gabbros of the Middle zone through a ∼5 m-thick microgabbro sheet, within and close to which small-scaled, concordant Fe-Ti oxide ore horizons are identified. Strong fractionation between HFSE and REE in a subset of samples is ascribed to cumulus titanomagnetite into which HFSE are preferentially incorporated over REE, as reflected in the parallel relations between Nb/La, Hf/Sm and Ti/Ti*. Both the isotropic and layered gabbros display cumulate textures and have similar mineral compositions (Mg# of clinopyroxene = ∼76–79 and An59–61, isotopic compositions [(87Sr/86Sri = 0.7044–0.7045 and εNd(t = +2.4 to +3.9] and trapped liquid contents inferred from Zr abundance (∼17–34 ppm. However, there are substantial variations in elemental abundances (V, Cr and PGE and ratios (Ti/V, La/Yb, Ba/Y and Cu/Pd between the two types of gabbros, features that cannot be explained by cumulate formation from a common magma in a closed system. The microgabbros generally resemble high-Ti Emeishan basalts in major element compositions, but their low trace element abundances indicate some lost of residual liquid is inevitable despite rapid nucleation and cooling. Combined with available data and observations, we propose a model involving in-situ crystallization, followed by magma recharge and closed-system fractionation to explain the formation of texturally distinctive gabbros at Nalaqing and the evolution of the lower part of the Panzhihua intrusion.

Influence of the menstrual cycle on compression-induced pain during mammography: correlation with the thickness and volume of the mammary gland.

Science.gov (United States)

Kitaoka, Hitomi; Kawashima, Hiroko

2018-03-01

In mammography, breast compression is necessary and an important factor influencing image quality. The purpose of this study was to determine the influence of the menstrual cycle on compression-induced pain during mammography and to evaluate the association between the thickness and volume of the mammary gland and pain. We examined basal body temperature and categorized the menstrual cycle into five phases. We executed breast compression in the craniocaudal view using a customized compression plate, to which we introduced an opening. We measured the thickness of the mammary gland under compression using echography. Immediately after releasing the compression, we evaluated pain using the visual analogue scale. We performed magnetic resonance imaging (MRI) on the same day and measured the volume of the mammary gland. The thickness of the mammary gland, pain, and the volume of the mammary gland were minimal in the late follicular phase and maximal in the late luteal and early follicular phases. It was shown that the changes in the thickness and volume of the mammary gland during the menstrual cycle accounted for the changes in compression-induced pain. On MRI examination of each breast quadrant, the same changes were observed in areas A and C. In area A, it was shown that both the anatomical characteristics and the increase in volume of the mammary gland were associated with pain. We concluded that the late follicular phase constitutes the optimal timing for mammography.

Effects of a dual-pump crude-oil recovery system, Bemidji, Minnesota, USA

Science.gov (United States)

Delin, Geoffrey N.; Herkelrath, William N.

2014-01-01

A crude-oil spill occurred in 1979 when a pipeline burst near Bemidji, MN. In 1998, the pipeline company installed a dual-pump recovery system designed to remove crude oil remaining in the subsurface at the site. The remediation from 1999 to 2003 resulted in removal of about 115,000 L of crude oil, representing between 36% and 41% of the volume of oil (280,000 to 316,000 L) estimated to be present in 1998. Effects of the 1999 to 2003 remediation on the dissolved plume were evaluated using measurements of oil thicknesses in wells plus measurements of dissolved oxygen in groundwater. Although the recovery system decreased oil thicknesses in the immediate vicinity of the remediation wells, average oil thicknesses measured in wells were largely unaffected. Dissolved-oxygen measurements indicate that a secondary plume was caused by disposal of the pumped water in an upgradient infiltration gallery; this plume expanded rapidly immediately following the start of the remediation in 1999. The result was expansion of the anoxic zone of groundwater upgradient and beneath the existing natural attenuation plume. Oil-phase recovery at this site was shown to be challenging, and considerable volumes of mobile and entrapped oil remain in the subsurface despite remediation efforts.

Petrophysical characteristics of basalt in the vadose zone, Idaho National Engineering Laboratory, Eastern Snake River Plain, Idaho

International Nuclear Information System (INIS)

Knutson, C.F.; Harrison, W.E.; Smith, R.P.

1989-01-01

We have used a core characterization system to measure bulk densities, porosities, and permeabilities of basalt lavas from the vadose zone at the Idaho National Engineering Laboratory (INEL). At the INEL, basalt lava flows with intercalated alluvial, aeolian, and lacustrine sediments extend to depths of one kilometer or more. Individual lava flows are generally less than 15 meters thick and commonly have vesicular tops and bottoms with massive basalt in their interiors. Petrophysical characterization is essential to an understanding of fluid movement in the vadose zone and in the saturated zone. Many hundreds of closely spaced permeability/porosity/bulk density measurements have defined the variability of these parameters within and between individual basalt flows. Based on geological logging and porosity/permeability measurements made on many hundred feet of core, we feel that a rather sophisticated and rigorous logging program is necessary to characterize these complex and highly variable basaltic flow units. This paper endeavors to provide a petrophysical/geological conceptual model of the Snake River Plain basalts from the vadose zone under the Radioactive Waste Management Complex area at the INEL. We hope that this model will aid in subsequent geotechnical logging in this portion of the Eastern Snake River Plain. 8 refs., 14 figs., 2 tabs

A two-dimensional time domain near zone to far zone transformation

Science.gov (United States)

Luebbers, Raymond J.; Ryan, Deirdre; Beggs, John H.; Kunz, Karl S.

1991-01-01

In a previous paper, a time domain transformation useful for extrapolating 3-D near zone finite difference time domain (FDTD) results to the far zone was presented. In this paper, the corresponding 2-D transform is outlined. While the 3-D transformation produced a physically observable far zone time domain field, this is not convenient to do directly in 2-D, since a convolution would be required. However, a representative 2-D far zone time domain result can be obtained directly. This result can then be transformed to the frequency domain using a Fast Fourier Transform, corrected with a simple multiplicative factor, and used, for example, to calculate the complex wideband scattering width of a target. If an actual time domain far zone result is required it can be obtained by inverse Fourier transform of the final frequency domain result.

Presence-only approach to assess landslide triggering-thickness susceptibility. A test for the Mili catchment (North-Eastern Sicily, Italy)

Science.gov (United States)

Lombardo, Luigi; Fubelli, Giandomenico; Amato, Gabriele; Bonasera, Mauro; Hochschild, Volker; Rotigliano, Edoardo

2015-04-01

This study aims at comparing the performances of a presence only approach, namely Maximum Entropy, in assessing landslide triggering-thickness susceptibility within the Mili catchment, located in the north-eastern Sicily, Italy. This catchment has been recently exposed to three main meteorological extreme events, resulting in the activation of multiple fast landslides, which occurred on the 1st October 2009, 10th March 2010 and 1st March 2011. Differently from the 2009 event, which only marginally hit the catchment, the 2010 and 2011 storms fully involved the area of the Mili catchment. Detailed field data was collected to associate the thickness of mobilised materials at the triggering zone to each mass movement within the catchment. This information has been used to model the landslide susceptibility for two classes of processes clustered into shallow failures for maximum depths of 0.5m and deep ones in case of values equal or greater than 0.5m. As the authors believed that the peculiar geomorphometry of this narrow and steep catchment played a fundamental role in generating two distinct patterns of landslide thicknesses during the initiation phase, a HRDEM was used to extract topographic attributes to express near-triggering geomorphological conditions. On the other hand, medium resolution vegetation indexes derived from ASTER scenes were used as explanatory variables pertaining to a wider spatial neighbourhood, whilst a revised geological map, the land use from CORINE and a tectonic map were used to convey an even wider area connected to the slope instability. The choice of a presence-only approach allowed to effectively discriminate between the two types of landslide thicknesses at the triggering zone, producing outstanding prediction skills associated with relatively low variances across a set of 20 randomly generated replicates. The validation phase produced indeed average AUC values of 0.91 with a standard deviation of 0.03 for both the modelled landslide

Root zone effects on tracer migration in arid zones

International Nuclear Information System (INIS)

Tyler, S.W.; Walker, G.R.

1994-01-01

The study of groundwater recharge and soil water movement in arid regions has received increased attention in the search for safe disposal sites for hazardous wastes. In passing through the upper 1 to 2 m of most soil profiles, tracers indicative of recharge such as Cl, 2 H, 18 O, Br, 3 H, and 56 Cl are subjected to a wide range of processes not encountered deeper in the profile. This transition zone, where water enters as precipitation and leaves as recharge, is often ignored when environmental tracers are used to estimate deep soil water flux and recharge, yet its effect may be profound. In this work, we reexamine the processes of root extraction and its effect on the velocity and distribution of tracers. Examples are presented for idealized conditions, which show clearly the relation between the root zone processes and the deep drainage or recharge. The results indicate that, when recharge is small and root zone processes are not accounted for, tracer techniques can significantly overestimate recharge until the tracer has moved well below the root zone. By incorporating simple models of root zone processes, a clearer understanding of tracer distributions and a more accurate estimate of recharge can then be made. 11 refs., 9 figs

The influence of fiber thickness, wall thickness and gap distance on the spiral nanofibrous scaffolds for bone tissue engineering

International Nuclear Information System (INIS)

Wang Junping; Shah, Ami; Yu Xiaojun

2011-01-01

We have developed a 3D nanofibrous spiral scaffold for bone tissue engineering which has shown enhanced cell attachment, proliferation and differentiation compared to traditional cylindrical scaffolds due to the spiral structures and the nanofiber incorporation. Some important parameters of these spiral scaffolds including gap distance, wall thickness and especially fiber thickness are crucial to the performance of the spiral structured scaffolds. In this study, we investigated the fiber thickness, gap distance and wall thickness of the spiral structure on the behavior of osteoblast cells. The human osteoblast cells are seeded on spiral structured scaffolds with various fiber thickness, gap distance and wall thickness and cell attachment, proliferation, differentiation and mineralized matrix deposition on the scaffolds are evaluated. It was found that increasing the thickness of nanofiber layer not only limited the cell infiltration into the scaffolds, but also restrained the osteoblastic cell phenotype development. Moreover, the geometric effect studies indicated that scaffolds with the thinner wall and gap distance 0.2 mm show the best bioactivity for osteoblasts.

Thickness measurement by using cepstrum ultrasonic signal processing