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Particles with directional interactions are promising building blocks for new functional materials and may serve as models for biological structures (1-3). Mutually attractive nanoparticles that are deformable owing to flexible surface groups, for example, may spontaneously order themselves into strings, sheets and large vesicles (4-6). Furthermore, anisotropic colloids with attractive patches can self-assemble into open lattices and the colloidal equivalents of molecules and micelles (7-9). However, model systems that combine mutual attraction, anisotropy and deformability have not yet been realized. Here we synthesize colloidal particles that combine these three characteristics and obtain self-assembled microcapsules. We propose that mutual attraction and deformability induce directional interactions via colloidal bond hybridization. Our particles contain both mutually attractive and repulsive surface groups that are flexible. Analogously to the simplest chemical bond--in which two isotropic orbitals hybridize into the molecular orbital of [H.sub.2]--these flexible groups redistribute on binding. Via colloidal bond hybridization, isotropic spheres self-assemble into planar monolayers, whereas anisotropic snowman-shaped particles self-assemble into hollow monolayer microcapsules. A modest change in the building blocks thus results in much greater complexity of the self-assembled structures. In other words, these relatively simple building blocks self-assemble into markedly more complex structures than do similar particles that are isotropic or non-deformable., Deformability and mutual attraction have recently been combined for the self-assembly of nanoparticles by grafting flexible polymers onto the surface of mutually attractive particles. This results in isotropic clusters (10) [...]

Remaining service life (RSL) has been defined as the anticipated number of years that a pavement will be functionally and structurally acceptable with only routine maintenance. Usually RSL is computed from pavement condition survey results. This paper presents a methodology whether RSL was estimated from pavement surface deflections. Deflection data were collected with a Dynatest 8000 falling weight deflectometer (FWD) from 1998 to 2006. Nonlinear regression procedure in the Statistical Analysis Software and Solver in Microsoft Excel were used in model development. The results showed that a sigmoidal relationship exists between RSL and center (FWD first sensor) deflection. Sigmoidal RSL models have very good fits and can be used to predict RSL at the network level based on the center deflection from FWD. DOI: 10.1061/(ASCE)TE.1943-5436.0000094 CE Database subject headings: Service life; Pavements; Deflections; Highways and roads. Author keywords: Remaining service life; Pavement surface deflections.

The San Ysidro fault is a spectacularly exposed normal fault located in the northwestern Albuquerque Basin of the Rio Grande Rift. This intrabasin fault is representative of many faults that formed in poorly lithified sediments throughout the rift. The fault is exposed over nearly 10 km and accommodates nearly 700 m of dip slip in subhorizontal, silicidastic sediments. The extent of the exposure facilitates study of along.strike variations in deformation mechanisms, architecture, geochemistry, and permeability. The fault is composed of structural and hydrogeologic components that include a clay-rich fault core, a calcite-cemented mixed zone, and a poorly developed damage zone primarily consisting of deformation bands. Structural textures suggest that initial deformation in the fault occurred at low temperature and pressure, was within the paleosaturated zone of the evolving Rio Grande Rift, and was dominated by particulate flow. Little geochemical change is apparent across the fault zone other than due to secondary processes. The lack of fault-related geochemical change is interpreted to reflect the fundamental nature of water-saturated, particulate flow. Early mechanical entrainment of low-permeability clays into the fault core likely caused damming of groundwater flow on the up-gradient, footwall side of the fault. This may have caused a pressure gradient and flow of calcite-saturated waters in higherpermeability, fault-entrained siliciclastic sediments, ultimately promoting their cementation by sparry calcite. Once developed, the cemented and clay-rich fault has likely been, and continues to be, a partial barrier to cross-fault groundwater flow, as suggested by petrophysical measurements. Aeromagnetic data indicate that there may be many more unmapped faults with similar lengths to the San Ysidro fault buried within Rio Grande basins. If these buried faults formed by the same processes that formed the San Ysidro fault and have persistent low-permeability cores and cemented mixed zones, they could compartmentalize the basin-fill aquifers more than is currently realized, particularly if pumping stresses continue to increase in response to population growth.

Dredged harbor mud is being increasingly used as backfilling and construction material in harbor development or reorganization to gain financial and operative advantages compared to disposal or ex situ treatment of the often contaminated material. However, the suitability of such soft organic sediments as construction material is unclear. This study presents geotechnical parameters for describing the one-dimensional consolidation based on large-scale long-term and standard oedometer tests using organic harbor mud from the Osthafen (East Harbor) reorganization project in Bremerhaven, Germany. Determined compression indices [C.sub.c] are in the range of peat, whereas the water permeabilities resemble those of clay. The coefficients of consolidation cv vary between [10.sup.-9] and [10.sup.-8] [m.sup.2]/s and large coefficients of secondary compression [C.sub.[alpha]] between 0.065 and 0.14 are observed. Differences in parameters from large-scale and standard tests can be explained by volume and time effects likely linked to biogeochemical degredation of organic carbon and the resulting methane degassing. A curve fit based on the Levenberg--Marquardt nonlinear least-squares optimization method confirmed the applicability of the Terzaghi theory in combination with a creep term. DOI: 10.1061/(ASCE)0733-950X(2009) 135:4(154) CE Database subject headings: Mud; Dredging; Sediment: Soil consolidation: Creep.

Problem statement: This study is concerned with a very important problem belonging in the effects of deformable inclined surfaces on a wheel with an elastic trunk. These effects can be represented by two effects: A lateral withdrawal of the trunk and lateral shift of the ground. Also this study aims to study these effects and analyze them mathematically to find a mathematical relation describes them. Approach: A free body diagram of the wheel which represented all forces affected is drawn then starting with the lateral component all angles are calculated, then by building a relations between these different angles and forces, the final relation is derived mathematically which describes the total deformation of the trunk. Results: It was found that inclination angle of the wheel with inclined surface has a nonlinear positive relationship with both trunk deformation and the displacement in x-direction. On the other hand the relation between the inclination angles with both rigidity factor of the trunk and ground volumetric factor is a non-linear negative relationship. Conclusion/Recommendations: The inclination angle was decreasing as both rigidity and ground volumetric factors are increasing. Inclination angle was increasing with the increase in both displacement (x) and trunks' deformation values. The study of trunk deformation was very important since it will lead to reconstruct the wheel system in the future to get more efficient system, and the slipping phenomenon will be easily analyzed in the future. Key words: Lateral withdrawal, lateral shift, corner angle, radial rigidity factor, volumetric factor of ground, free diameter of wheel, elastic trunk., INTRODUCTION The Course movement of a wheel at a cross inclination basic surfaces, characteristic for conditions of work of tractors on slopes, can be defined by both lateral withdrawal of [...]

We measured bulk and surface dielectric breakdown thresholds of pure silica for 14 ps and 8 ns pulses of 1064 nm light. The thresholds are sharp and reproducible. For the 8 ns pulses the bulk threshold irradiance is 4.75 [+ or -] 0.25 kW/[micro][m.sup.2]. The threshold is approximately three times higher for 14 ps pulses. For 8 ns pulses the input surface damage threshold can be made equal to the bulk threshold by applying an alumina or silica surface polish. OCIS codes: 140.3330, 060.2290, 190.5940, 190.5890.

A visual test method for detecting microdefects under fine surfaces is described. A new MO microscope that has a laser source, a CCD camera, and an exciting coil is developed for this work. A pulse generator supplies an intermittent square pulse to the exciting coil, which can intensify eddy currents yet reduce the working temperature of the exciting coil and sample. The magnetic field variation produced by the imbedded defect causes a rotation of the polarization plane of the reflected beam. Therefore the reflected beam carries an image of the defect, which is received by a CCD camera. The optical arrangement guarantees that no light is reflected back to the laser. The system was tested with a calibrator, which has an artificial subsurface defect; such a test attains a visual detected image. To our knowledge this is the first time an image of a subsurface defect has been distinctly detected with a MO sensor system. OCIS codes: 040.0040, 110.0180.

Differential interferometric synthetic aperture radar (DInSAR) is a deformation measurement technique that couples two interesting characteristics. First, being based on remotely sensed data it offers operational advantages, like low cost data acquisition, wide area coverage, and temporally regular acquisitions. Second, it can be based on rigorous modeling and estimation procedures, which allows some of the most advanced techniques to derive measurements with high quality standards, comparable with those of some geodetic methods. The scope of this paper is to describe two complementary approaches to measure slow (from a few millimeters up to some centimeters per year) and fast land deformation (up to few meters per year). Emphasis is given to the description of the former approach, which requires multiple SAR images of the same phenomenon and an advanced analysis procedure. The effectiveness of both approaches is illustrated through two applications on mining areas of small spatial extent located in Spain. In one case the DInSAR capability to fully detect shape and magnitude of an unknown fast deformation phenomenon is highlighted, whereas in the second one a detailed deformation map is derived over an urban area, where deformations up to 30 mm/year occur. DOI: 10.1061/(ASCE)0733-9453(2007)133:2(66) CE Database subject headings: Data analysis; Algorithms; Estimation: Measurement; Deformation; Mining; Subsidence.

Crustal movements and deformation within the diffuse Pacific-North America (Pa-NA) plate boundary are dominated by the right-lateral motion between the two plates. By using the Pa-NA pole of rotation (PoR) spherical coordinate system, we decompose observed crustal movements into parallel and normal components to the Pa-NA plate motion. We transformed the 840 velocity vectors of the Southern California Earthquake Center (SCEC) 3.0 velocity field into the Pa-NA PoR system in order to characterize the interseismic velocity across the plate boundary. Our results show that despite the very different deformation styles occurring across the San Andreas fault, the fault trace follows the half plate motion contour. Deviation occurs in the southern section, where the half motion contour correlates with the San Jacinto and Imperial fault segments. Our analysis yields interesting asymmetric patterns in both parallel and normal components. The parallel component shows asymmetrical velocity gradients across the San Andreas fault, and the normal component indicates compression southwest of the Big Bend, but not northeastward. The observations are compared with visco-elastic modeling results, which show a similar velocity field. The main disagreements between the observations and the model are in a narrow band along the San Andreas fault and in the Mojave block, suggesting that crustal heterogeneities and additional unmodeled fault segments should be considered in future models. Keywords: crustal deformation, plate motion, San Andreas fault, viscoelastic model, deformation asymmetry.

This paper presents an application of a coupled thermo/hydro/chemical/ mechanical model via simulation of a laboratory experiment in order to investigate the transport behavior of ions in bentonite pore water. Chemical reactions considered include ion exchange reactions involving major cations ([Na.sup.+], [K.sup.+], [Mg.sup.2+], and [Ca.sup.2+]) and precipitation-dissolution of trace minerals (calcite, dolomite, anhydrite, and halite). The following conclusions are drawn based on the numerical results. The development of both the temperature and moisture fields was captured by simulation, and a good correlation with the experimental water uptake results was observed. For all ions, the model showed a good qualitative and reasonable quantitative agreement with the experimental results. DOI: 10.1061/(ASCE)0733-9399(2007)133:3(348) CE Database subject headings: Unsaturated soils; Numerical models; Soil deformation; Nuclear wastes; Chemical equilibrium; Transport phenomena.

This paper presents an investigation of the inclusion of some aspects of chemical behavior within a model of coupled thermo/hydro/chemical/ mechanical behavior of unsaturated soils. In particular, multicomponent reactive chemical transport behavior is addressed. The chemical transport model is based on the advection/dispersion/reaction equation, while geochemical reactions are considered via coupling with an established geochemical speciation model. A numerical solution of the governing differential equations is achieved by the use of the Galerkin-weighted residual method for spatial discretization and an implicit backward Eulerian finite-difference method for temporal discretization. The solution of the geochemical reactions is achieved externally to the main solution procedure. Coupling between the chemical transport and geochemical models is achieved via the implementation of both sequential iterative and sequential noniterative techniques. Three application problems are then presented to demonstrate the capability of the coupled model. DOI: 10.1061/(ASCE)0733-9399(2007)133:3(338) CE Database subject headings: Unsaturated soils; Numerical models; Soil deformation; Bentonite; Nuclear wastes; Chemical equilibrium; Transport phenomena.

A 220-km-long, single-channel seismic reflection profile crosses the northern Sumatra margin and presumed rupture zone of the December 2004 [M.sub.w]9.2 tsunamigenic earthquake and images active deformation across the forearc. At the largest wavelength (tens of kilometers), the forearc surface is defined by a steep, 55-km-wide outer slope, a 110-km-wide upper slope forming a broad depression between two forearc highs, and a 25-km-wide steep inner slope between the landward high and forearc basin. Superimposed on these prism-wide variations are anticlinal ridges spaced ~13 km apart; the inner and outer slopes are characterized by landward and seaward fold vergence, respectively. Between anticlines, growth strata deposited in slope basins are folded at -2-3 km wavelengths. These small folds deform the seafloor and increase in amplitude with depth, verging toward anticlinal hinges. We suggest that long-wavelength variations are consistent with variations in strength across the forearc. The ~13 km anticline spacing implies deformation of a slope apron that deforms independently of a stronger wedge interior. Growth strata geometries indicate ongoing deformation within individual basins. Our model for prism architecture suggests that the wedge interior advances during great earthquakes like the 2004 [M.sub.w]9.2 event, peeling up shallower and less competent trench fill, deforming the toe and the upper slope of the forearc, and producing seabottom uplift responsible for the tsunami. Keywords: forearc, Sumatra, growth sedimentation, wedge, tsunami.

[1] This paper examines how active faulting in the Turkey-Iran-Caucasus region accommodates the Arabia-Eurasia collision and the velocity field observed by GPS. The overall shortening across the zone is, in general, spatially separated ('partitioned') into right-lateral strike slip in the Turkish-Iranian Plateau and thrusting in the Greater Caucasus. A band of counterclockwise rotating NW-SE right-lateral strike-slip faults accommodates a NW-SE gradient in NE directed velocity (relative to Eurasia) between the Black and Caspian seas. A NNW-SSE band of previously unrecognized oblique normal faults is present on the Turkey-Iran border. We estimate the offsets on faults from geomorphological features and show that these offsets can be achieved in 5 [+ or -] 2 Ma at present rates. This implies a reorganization of deformation in the collision zone at that time, after the initial collision at ~12 Ma, probably in response to mantle-induced dynamic uplift. doi: 10.1029/2005TC001906.

[1] For the Puna Plateau and Eastern Cordillera of NW Argentina, the temporal and spatial pattern of deformation and surface uplift remain poorly constrained. Analysis of completely and partially reset apatite fission track samples collected from vertical profiles along an ESE trending transect extending from the plateau interior across the southern Eastern Cordillera at ~25[degrees]S reveals important constraints on the deformation and exhumation history of this part of the Andes. The data constrain the Neogene Andean development of the Eastern Cordillera as well as rift-related exhumation for some of the sampled locations in the Late Jurassic/Early Cretaceous. An intervening Eocene-Oligocene exhumation episode in the southern Eastern Cordillera was probably related to crustal shortening. Subsequent reburial of the area by Andean foreland basin strata commenced between 30 and 25 Myr. Magnitude and duration of sedimentation, revealed by thermal modeling, differ between the sample locations, pointing to an eastward propagating basin system. In the southern Eastern Cordillera, Andean deformation commenced at 22.5-21 Myr, predating both the inferred formation of significant topography by 5-7.5 Myr and preservation of sediments in the adjacent Cenozoic basins by 6.5-8 Myr. Comparing the calculated structural depth of partially reset samples suggests that newly formed west dipping reverse faults along the former Salta Rift margin accommodated most of the Neogene tectonic movement. Late Cenozoic deformation at the southern Eastern Cordillera began earlier in the west and subsequently propagated eastward. The lateral growth of the orogen is coupled with a foreland basin system developing in front of the range and then becomes subsequently compartmentalized by later emergent topography. doi: 10.1029/2005TC001894.

The effects of axis alignment errors, planetary rotation, and tidal forces on rotating liquid mirrors are analyzed. These produce a surface distortion that decreases exponentially with distance inward from the rim with a characteristic length l = [square root of 3hf/2], where h is the thickness of the fluid and f is the focal length. Even a small tilt of the rotation axis can produce a significant deformation of the optical surface. The maximum surface height error is 3[epsilon]l, where s is the tilt angle and is typically of the order of 1.5 [micro]m for a 1 arc sec tilt. The main optical effect of the wave is to produce a ring, with angular diameter 6[epsilon], offset by half of the diameter in the direction opposite the tilt. This diamond ring aberration can be avoided by accurate alignment of the rotation axis or by masking the outer few centimeters of the mirror. Planetary rotation produces a small deformation of the order of 100 nm for a 10 m telescope at low latitude on Earth. This deformation can be canceled by a small tilt of the rotation axis. Tidal forces produced by the Moon, or by the Earth in the case of a lunar telescope, produce an inconsequential, subnanometer, surface deformation.

A fully nonlinear finite element analysis for prediction of localization/delocalization and compression fracture of moderately thick imperfect transversely isotropic rings, under applied hydrostatic pressure, is described. An analogy to soliton helps in the understanding of the localization and delocalization phenomena leading to the mode II compression damage/fracture at the propagation pressure.

[1] The active tectonics at the front of the southern Apennines and in the Adriatic foreland is characterized by E-W striking, right-lateral seismogenic faults, interpreted as reactivated inherited discontinuities. The best studied among these is the Molise-Gondola shear zone. The interaction of these shear zones with the Apennines chain is not yet clear. To address this open question, we developed a set of scaled analogue experiments, aimed at analyzing (1) how dextral strike-slip motion along a preexisting zone of weakness within the foreland propagates toward the surface and affects the orogenic wedge; (2) the propagation of deformation as a function of displacement; and (3) any insights on the active tectonics of southern Italy. Our results stress the primary role played by these inherited structures when reactivated and confirm that regional E-W dextral shear zones are a plausible way of explaining the seismotectonic setting of the external areas of the southern Apennines. Citation: Di Bucci, D., A. Ravaglia, S. Seno, G. Toscani, U. Fracassi, and G. Valensise (2006), Seismotectonics of the southern Apennines and Adriatic foreland: Insights on active regional E-W shear zones from analogue modeling, Tectonics, 25, TC4015, doi:10.1029/ 2005TC001898.

[1] We use satellite imagery and field observations to investigate the distribution of active faults around Birjand in eastern Iran to determine how the transition between conjugate zones of faulting can be accommodated by diffuse active faulting. In the south of the study area, right-lateral strike-slip faults of the Sistan Suture Zone end in thrusts which die away westward from the strike-slip faults. These thrust terminations appear to allow a northward change to E-W thrusting in central parts of the study area. The introduction of E-W thrusting is, in turn, likely to facilitate a change to E-W left-lateral faulting north of the study region. The relatively diffuse pattern of active faulting at Birjand relates to the regional transition between N-S and E-W strike-slip faulting in northeast Iran, which involves a change from nonrotational to rotational deformation. The change from N-S to E-W faulting is likely to result from the orientation of preexisting structures in Iran and western Afghanistan, which are roughly parallel to the active fault zones. The features described at Birjand also show the influence of preexisting structure on the location and style of active faulting at a local scale, with the position of individual faults apparently controlled by inherited geological weaknesses. Very few modern earthquakes have occurred in the region of Birjand and yet destructive events are known from the historical record. The large number of active faults mapped in this study pose a substantial seismic hazard to Birjand and surrounding regions. Citation: Walker, R. T., and M. M. Khatib (2006), Active faulting in the Birjand region of NE Iran, Tectonics, 25, TC4016, doi: 10.1029/2005TC001871.

[1] New U-Pb (titanite, apatite, futile) and [sup.40]Ar/[sup.39]Ar (hornblende, muscovite, biotite) data are linked with existing pressure-temperature-deformation paths to impose detailed temporal constraints on the juxtaposition and unroofing of domains in an extensive (>20,000 [km.sup.2]) region of exhumed lower crust in the East Lake Athabasca region of the western Canadian Shield. In the ~200 m.y. between circa 1.9 Ga high-pressure granulite facies metamorphism and circa 1.7 Ga unconformable deposition of Athabasca basin sediments on the exhumed rocks, our analysis reveals at least three distinct phases of unroofing at different rates. Specifically, we distinguish (1) an early phase of extensional unroofing in the Chipman domain at rates of 1.5-2.0 km/m.y, from ~1.0 GPa to ~0.8 GPa associated with mafic magmatism and metamorphism, (2) an episode of regional contractional uplift and associated unroofing along the Legs Lake shear zone at circa 1850 Ma from 0.7-0.8 GPa to 0.4-0.5 GPa, and (3) a final period of extensional unroofing at rates of 0.2-0.3 km/m.y. from 0.4 to 0.5 GPa that culminated in transport of current exposures to near-surface conditions. The cooling patterns and retrograde assemblages are consistent with pauses between exhumational phases. The apparent convergence of disparate higher temperature histories in several deep crustal domains at circa 1.89-1.88 Ga implies their juxtaposition at 0.7-0.8 GPa conditions. Regional east directed thrusting of the deep crustal domains as a coherent unit at 1.85 Ga juxtaposed the granulites with middle crustal Hearne domain rocks at 0.4-0.5 GPa conditions. The detailed exhumational history allows correlation with changing regional tectonic regimes associated with the amalgamation of Laurentia. The temporal and spatial heterogeneity of exhumation patterns in the East Lake Athabasca region may be a common feature of the unroofing histories of lower crustal rocks. Citation: Flowers, R. M., K. H. Mahan, S. A. Bowring, M. L. Williams, M. S. Pringle, and K. V. Hodges (2006), Multistage exhumation and juxtaposition of lower continental crust in the western Canadian Shield: Linking high-resolution U-Pb and [sup.40]Ar/[sup.39]Ar thermochronometry with pressure-temperature-deformation paths, Tectonics, 25, TC4003, doi: 10.1029/2005TC001912.

[1] The Lloyds River Fault Zone is a 10-15 km wide amphibolite-grade shear zone that formed during the Ordovician Taconic Orogeny. It separates ophiolites and arc-back-arc complexes formed in Iapetus from a peri-Laurentian microcontinent (Dashwoods microcontinent). The Lloyds River Fault Zone comprises three high-strain zones, dominantly composed of mylonitic amphibolites, separated by less deformed plutonic rocks. Structural, age and metamorphic data suggest the Lloyds River Fault Zone accommodated sinistral-oblique underthrusting of ophiolites underneath the Dashwoods microcontinent prior to 471 [+ or -] 5 Ma at 800[degrees]C and 6 kbar. Plutonic rocks within the Lloyds River Fault Zone comprise two suites dated at 464 [+ or -] 2 plus 462 [+ or -] 2 and 459 [+ or -] 3 Ma, respectively. The younger age of the plutons with respect to some of the amphibolites, evidence for magmatic deformation, and the elongate nature of the plutons parallel to the Lloyds River Fault Zone suggest they were emplaced within the fault zone during deformation. Both intrusive episodes triggered renewed deformation at high temperatures (770-750[degrees]C), illustrating the positive feedback between deformation and magmatism. Offshoots of the plutons intruded undeformed ophiolitic gabbros outside the Lloyds River Fault Zone. Deformation localized within the intrusive sheets, coeval with static contact metamorphism of the host gabbros, leading to the development of new, small-scale shear zones. This illustrates that channeling of plutons into shear zones and nucleation of shear zones in melt-rich zones may occur simultaneously within the same fault system, citation Lissenberg, C. J., and C. R. van Staal (2006), Feedback between deformation and magmatism in the Lloyds River Fault Zone: An example of episodic fault reactivation in an accretionary setting, Newfoundland Appalachians, Tectonics, 25, TC4004, doi: 10.1029/2005TC001789.

Experiments of a material-surface treatment using the nonthermal plasma generated by the dielectric barrier discharge (DBD) at atmospheric pressure in ambient air are carried out on a laboratory scale to see if the DBD can be used in enhancing the surface hydrophobicity. It is well known that the DBD can react with the material surface and induce physical and chemical changes to improve the surface wettability. The main purpose of this paper, however, is to look into the possibility of using the same experimental setup to do the opposite, i.e., to improve the surface hydrophobicity for a better insulation performance, which can be judged by the contact-angle and surface-resistance measurements, and verified by the wet flashover voltage test. To enhance the surface hydrophobicity, the glass surface is sprayed with a silicon liquid before it is exposed to the DBD treatment, and it is found that the formed hydrophobic coating is stable enough to endure both the thermal and chemical aging tests. The improvement of hydrophobicity depends on the DBD voltage and treatment time. It seems that there exists an optimum treatment time for a certain applied voltage of the DBD. Possible interaction between the DBD plasma and the material surface is discussed. Index Terms--Dielectric barrier discharge (DBD), hydrophilicity, hydrophobicity, nonthermal plasma, surface modification.

This paper defined a complete set of imaging based indices for different levels of coarse aggregate morphologies, i.e., the flat and elongated (FE) ratio, angularity index (AI), and surface texture (ST) index, and investigated their effects on permanent deformation behavior of hot mix asphalt (HMA). Image analyzed coarse aggregates were used to prepare eighteen Superpave HMA specimens using job mix formulas from ten State highway agencies and tested for permanent deformation at a specified high temperature. The permanent deformation data when linked to the morphological indices of the coarse aggregate, showed the best correlations with the ST index. The FE ratio demonstrated no measurable effects on the permanent deformation due to low percentage of flat and elongated particles used in the mixes. The influences of the AI and ST indices on the permanent deformation were especially significant when differences in the asphalt mix aggregate gradations were properly considered. A possible mechanism of coarse aggregate morphology affecting the stability and permanent deformation behavior of HMA was proposed in terms of particle geometrical interference in HMA. CE Database subject headings: Aggregates; Shape; Asphalt mixes; Deformation.

Free surface deformation and Marangoni convection in immiscible droplets positioned by an electrostatic field and heated by laser beams under microgravity is studied. The findings reveal that inner interface demarking the two immiscible fluids maintains its sphericity in microgravity.

Orientation contrast imaging and quantitative electron back-scatter diffraction analysis of a zircon collected from an Indian Ocean gabbro reveal intragrain crystallographic misorientations (up to 14[degrees]) and low-angle orientation boundaries concentrated in the zircon tips. These features represent the formation and migration of dislocations and provide the first evidence of crystal-plastic deformation of zircon under crustal conditions. Panchromatic and wavelength cathodoluminescence (CL), combined with quantitative rare earth element (REE) ion microprobe analyses, demonstrate modification of zircon REE chemistry within the areas of crystal plasticity. These data indicate that the enhanced diffusion of REEs into the zircon is spatially linked to the presence of dislocations that behave as high-diffusivity pathways, increasing bulk diffusion rates and effective diffusion distances in the zircon by several orders of magnitude. In addition, discrete ~2 [micro]m zones of reduced panchromatic CL correspond exactly to the position of low-angle orientation boundaries and demonstrate a defect dependence on CL signal at high dislocation densities. The presence of deformation-related crystal-plastic microstructures in zircon, and their role in modifying elemental diffusion, questions the commonly made assumption of chemical robustness and has fundamental implications for the interpretation of zircon trace-element and isotopic data. Keywords: microstructure, diffusion, deformation, geochemistry, EBSD.

Abstract: This study uses new information acquired from field mapping, mineral exploration boreholes, and seismic reflection profiles to constrain the structural geology, deformation mechanisms, and timing of the Penobsquis salt [...]

This study compares the flattening and indentation approaches for modeling single asperity contacts in order to reveal quantitatively their different behaviors in terms of the constitutive relationships for the contact parameters and deformation regimes. The comparison is performed with four empirical models recently developed for flattening and indentation based on the finite element method. In the elasto-plastic regime, the classic Hertz solution does not hold and, therefore, different mechanical behavior was obtained for flattening and indentation cases. Consequently, the contact condition and relative strength of mating surfaces should be considered when choosing between indentation or flattening models. [DOI: 10.111511.2114948]

Since the 1960s, a uniform circular vertical contact stress has been used to model the tire/pavement interface in asphalt pavements. Recent experimental measurements show that this assumption cannot be used to model the actual interaction. This study investigated the influence of nonuniform contact stress distribution on the stress distribution and permanent deformation profile in asphalt pavements. A previous study measured the tire contact stresses between the pavement surface and moving pneumatic tires. Material properties of a hot mix asphalt mixture used at WesTrack were obtained from compressive strength tests within the framework of an elastic-viscoplastic constitutive model. A three-dimensional finite element (FE) analysis was performed based on boundary conditions and measured vertical stresses at WesTrack. The tire pressure distribution was dependent on the tire load and significantly influenced the pavement response. The FE analysis based on the elastic-viscoplastic model was able to simulate the measured permanent deformation profiles. CE Database subject headings: Finite elements; Asphalt pavements; Contact pressure; Viscoplasticity; Deformation.

[1] The Western-Eastern Blue Ridge boundary involved formation by premetamorphic thrusting of an oceanic fragment/accretionary wedge/island arc upon Laurentian basement and metasedimentary cover. Detailed outcrop-scale mapping, structural and petrographic analysis reveal both terranes experienced the same deformation at the same metamorphic grade. Early [F.sub.1] and [F.sub.2] isoclinal folds are overprinted by [F.sub.3] open to tight folds; [F.sub.3] transposes [S.sub.2] to an axial planar cleavage ([S.sub.3]), the youngest penetrative feature. Prekinematic to synkinematic (relative to [S.sub.2]) Barrovian metamorphism attained kyanite grade in the Western Blue Ridge (WBR), upper amphibolite facies in the Eastern Blue Ridge (EBR), and anatexis in both terranes. Postkinematic [M.sub.2]B is characterized by appearance of fibrolite throughout the kyanite zone, coarsening to granular sillimanite and identification of a kyanite-sillimanite isograd in the WBR. [D.sub.3] strain was accommodated by dynamic recrystallization of quartz, neocrystallization, folding, and basal slip of micas, pressure solution of plagioclase, folding of kyanite, and fracturing of garnet. Scattered lower greenschistfacies [M.sub.4] static retrograde metamorphism resulted in replacement of kyanite and garnet by sericite and chlorite, respectively. Although the juxtaposition of two lithologically distinct terranes implies a fault relationship, polymetamorphism and deformation obliterated any microfabrics, mineral assemblages, or structures that might have developed during premetamorphic thrusting. The boundary cannot be an extension of a continent-scale, dextral strike-slip fault system inferred to have developed along Laurentian margin in the Devonian. doi: 10.1029/2004TC001643.

[1] The upper Miocene Misaki and Nishizaki formations on the Miura and Boso peninsulas in central Japan preserve the deformation features of an off-scraped accretionary prism. The spatial distribution, geometry, and style of accretion-related deformation with paleotemperature and burial depth estimation are elucidated in this study. The deformation structures and textures are similar to those of modern accretionary prisms. The low maximum paleotemperature ( doi:10.1029/ 2005TC001823.

[1] We perform numerical modeling to investigate the mechanisms leading to the postcollisional tectonic evolution of the Alps. We model the lithospheric deformation as a viscous thin sheet with vertically averaged rheology and coupled with surface mass transport. The applied kinematic boundary conditions simulate the convergence between the Adria indenter and the European foreland during the last 35 Myr. Model predictions of elevation, lithospheric structure, erosion/sedimentation pattern and vertical axis rotation are compared with observations of the planform shape of the chain, topography, crustal thickness, distribution of rock exhumation and sediment thickness, and paleomagnetic rotations. Thickening of the lithosphere in the Alpine region is shown to be highly sensitive to the assumed viscosity law, to the strength contrasts between the different regions and to the surface mass transport. Modeling results indicate that the large-scale deformation of the Alps during the postcollisional phase is mainly controlled by accommodation of convergence in a weak orogenic zone caught between a nearly rigid Adria plate and a strong European foreland. Modeling of the present-day stress field shows that (1) the present rotation of Adria is responsible for the change of extension direction from strike-perpendicular in the western Alps to strike-parallel in the east and (2) the strike-perpendicular extension observed in the western Alps is likely due to lateral variations of gravitational potential energy. The results suggest a NNE shift of about 700 km of the Euler pole of Adria relative to Europe from its mean position during postcollisional deformation to the present day. doi: 10.1029/2004TC001754.

[1] The Kazerun Fault is a N-S trending fault zone, which obliquely truncates the NW-SE trending Zagros Fold-Thrust Belt. This active fault zone is an ancient structural lineament which has controlled the structure, sedimentation, and subsidence of the central part of the Zagros since the Early Cambrian and has had an influence on the formation of the hydrocarbon system of the belt. The Kazerun Fault limited the distribution of the Cambrian Hormuz salt (the major decollement horizon that separates the Precambrian basement from the thick sedimentary cover) to the west. Its later reactivation with other N-S trending fault zones (e.g., the Izeh Fault Zone) during the Cretaceous resulted in major sedimentary thickness and facies variations along the belt. This study presents a new interpretation for the evolution of the Kazerun Fault Zone based on field evidence and a review of various published and unpublished data. It is argued that at the surface, the fault zone is delineated by four north-south trending segments and that marked differences occur in the distribution of deformation on either side of the fault segments in the Late Tertiary. During this time these segments acted as transfer faults (lateral ramps) linking different segments of the Zagros deformation fronts. doi: 10.1029/2004TC001725.

A technique for viscosity measurement is developed based on the principle of laser-induced surface deformation. The technique is useful at high viscosities since the measurement takes only a few seconds even in the specimen with 10 to thee poser of 6 cSt, and the method has a great advantage of a noncontact feature and is appropriate for measuring the liquids that strongly dislike contamination.

The effect of the humidity on surface deformation and adhesion of mica surfaces using a surface forces apparatus is explained. The Maugis model of contact elasticity is used to make an analysis of these effects.

The partitioning of deformation into wrench-and contraction-dominated deformation domains is a widely reported but poorly described phenomenon in ancient transpression zones. This paper documents spectacularly exposed examples of such partitioning from the Southern Uplands terrane in SE Scotland (Berwickshire), which was deformed during late Llandovery to Wenlock time. A well-exposed coastal section from Eyemouth to Burnmouth preserves a broadly homoclinal sequence in which a highly heterogeneous array of contemporaneous structures formed during regional triclinic transpression. The deformation involved components of NW--SE contraction with subvertical extension, top-to-the-SE thrusting and top-to-the-SW sinistral shear. In the northern third of the section studied these components are partitioned into a series of fault-bounded, metre-to kilometre-scale structural domains that contain geometrically and kinematically distinct assemblages of variably curvilinear folds, strike-slip detachments and locally transecting cleavages. The structures are all broadly contemporaneous and, in individual domains, record either non-coaxial contractional-or sinistral wrench-dominated strains. Similar highly heterogeneous, domainal structural patterns are likely to be found in other regions of oblique convergence in both ancient and modem settings. Keywords: Southern Uplands, transpression, deformation, strain.

This paper reports the results of applying a computational method called the quantized elastic deformational model, to the determination of conformational flexibility of the supermolecular complex of human fatty acid synthase. The essence of this method is the ability to model large-scale conformational changes such as domain movements by treating the protein as an elastic object without the knowledge of protein primary sequence and atomic coordinates. The calculation was based on the electron density maps of the synthase at 19 [Angstrom]. The results suggest that the synthase is a very flexible molecule. Two types of flexible hinges in the structure were identified. One is an intersubunit hinge formed by the intersubunit connection and the other is an intrasubunit hinge located between domains I and II. Despite the fact that the dimeric synthase has a chemically symmetric structure, large domain movements around the hinge region occur in various directions and allow the molecule to adopt a wide range of conformations. These domain movements are likely to be important in facilitating and regulating the entire palmitate synthesis by coordinating the communication between components of the molecule, for instance, adjusting the distance between various active sites inside the catalytic reaction center. Finally, the ability to describe protein motions of a supermolecular complex, without the information of protein sequence and atomic coordinates, is a major advance in computational modeling of protein dynamics. The method provides an unprecedented ability to model protein motions at such a low resolution of structure. conformational flexibility | elastic deformation | large conformational change | elastic network

Research is presented concerning the use of an atomic force microscope to investigate the molecular distortions in crystals which had been deformed by impact or shock. The permanent lattice structure is discussed.

Entropy change in heat flux is examined.

The mechanism of forcefill, used in the metallization of ICs, is described.

Experimental results are presented along the lines of the early work of Moore (1948) where a hard smooth roller is pressed into a softer rough surface to study the resulting real to apparent areas of contact and their associated local contact pressures. Results are presented for a hard steel roller deforming mild-steel and aluminum-alloy rough surface specimens. An analysis of the local contact mechanics is performed before and after indentation using a recently developed numerical elastic contact simulation method which allows local asperity contact pressures and areas to be studied in detail. The method is shown to reveal the level and distribution of pressures and asperity contact areas prevalent during the indentation process, and therefore allows the contribution of elastic and plastic load support to be quantified. The persistence of asperities during such indentation tests is discussed in terms of the pressures the asperities can support in relation to reported mechanisms of persistence. Results of subsequent sub-surface stresses are also presented and discussed in terms of how the method might be used to create an elastic-plastic deformation model that can account for asperity persistence in future numerical contact simulation models.

The influence of surface roughness on the bulk deformation of line contacts is studied. The model of Greenwood and Tripp (1967) will be extended to line contacts. It is found that the central pressure is a very good parameter to characterize the pressure distribution of rough line contacts. Function fits of the central pressure, the effective half width, the real area of contact, and the number of contacts are made. Comparison is made with the work of Lo (1969) and Greenwood et al. (1984).

Flattening of random rough surfaces on a workpiece undergoing bulk deformation has been analyzed using a model of the surface consisting of just two wavelength components. Asperities are flattened at a rate which depends on the ratio of the initial r.m.s, amplitudes of the long and short wavelength components. The flattening behavior of the long wavelength asperities only becomes important when the amplitude of the long wavelength asperities is much greater than that of the shorter wavelength asperities. The surface modification was investigated experimentally by cold rolling of aluminum strips. The power spectral density of the roughness was used to extract appropriate amplitudes for the short and long wavelength components of roughness. The change in roughness amplitudes showed excellent agreement with theory.

The Laramide orogeny of the western United States is proposed as a modern analogue for the Silurian-Devonian Acadian orogeny and subsequent diachronous, voluminous, short-lived magmatism and basin formation in the northern Appalachians. Shallowing of the Benioff zone accounts for several enigmatic features associated with plate convergence in the northern Appalachians, including (1) Wenlockian-Ludlovian termination of arc-related magmatism in the Avalon terrane followed by a period of relative magmatic quiescence from 395 to 380 Ma, and (2) diachronous migration of the Acadian deformation front from ca. 415 Ma in the southeast to ca. 370 Ma in the northwest, extending more than 600 km into the continental interior. The flattening of the subduction zone is attributed to overriding of a plume by the convergent margin, which may explain (1) the abrupt termination of magmatic quiescence by 380-370 Ma, and voluminous felsic magmatism and production of plume-related lamprophyres in the southeast (Meguma terrane) as the plume thermally eroded the oceanic lithosphere, causing melting of the lower crust; (2) Late Devonian regional high-temperature, low-pressure metamorphism in the Meguma terrane related to the thermal anomalies above a plume; (3) synchronous Devonian emplacement of Meguma gold deposits and associated siderophile elements, possibly derived from fluid circulation above an ascending plume; (4) rapid Late Devonian uplift and erosion of as much as 10 km due to dynamic uplift over a plume; (5) migration of magmatism to the north (Avalon terrane, Cobequid highlands) so that plume-related Carboniferous magmatism occurred in and around the Carboniferous-Permian Maritimes basin; (6) the high-density lens at the base of the crust beneath the Maritimes basin, the product of plume-derived underplated mafic rocks; and (7) a subsidence mechanism for formation of the Maritimes basin by cooling of a decapitated plume head.

Research was conducted to examine the surfaces of GaN films deposited by metalorganic chemical vapor deposition and molecular beam epitaxy using atomic force microscopy. The objective was to explain how the surface structures form and how they can be controlled. Results demonstrate that the spiral hillock formation was dependent on the critical radius of curvature of the step-line and the miscut terrace width.

Research was conducted to examine the laser induced deformation of unsupported or weakly adherent thin films in the framework of a simple dynamical model for the interacting vacancy density and deformation fields of the film. Results demonstrate that one-dimensional gratings are always unstable in isotropic systems. In irradiation with focused laser beams, rose deformation patterns naturally arise in the model, which is in qualitative agreement with experimental observations.

Research was conducted to examine the elastic field and the interaction energy associated with surface steps and adatoms. A harmonic model is proposed that presents a number of considerable advantages when compared to continuum models of Embedded Atom Method (EAM) simulations. Results are in good agreement with atomic EAM simulation results as well as the far-field predictions of continuum elastic theory.

Electromagnetic riveting, used in some aerospace assembly processes, involves rapid deformation, leading to the finished rivet configuration. Analysis of this process is described for the case of an aluminum rivet joining typical aluminum structural elements. The analysis is based on a finite element method that includes the effects of heating, due to rapid plastic deformation of the material, on the material properties. Useful details of material deformation and thermal history and the final rivet and structure configuration and states of stress and strain are obtained. These results have significant implications in the design, implementation, and improvement of practical fastening processes in the aerospace industry.

A study was conducted to analyze the deformation of particles during the dynamic compaction of metal powders using numerical analyses. The shear stress transfer across particle interface was determined through frictional contact. Simulations were carried out as a nonlinear explicit dynamic analysis process. Results indicated that increases in temperature correlated with interparticle welding and supported increased strength for dynamically compacted parts.