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The curve geometry influences the driver's speed choice behavior when passing through a horizontal curve. Hence, speed prediction models are essential to ensure highway safety, particularly under heterogeneous traffc conditions prevailing in India, where various classes of vehicles occupy the roadway space. Toward this, the present study aims to develop an operating speed increment and decrement model to identify the influence of the highway geometry variables on the drivers' speed choice behavior. The National Highway NH-953 is located on hilly terrain, from which 15 curves with various geometric characteristics were selected. The speed data were collected using the radar gun for three dominant vehicle types: motorized two-wheelers (2Ws), cars, and heavy commercial vehicles (HCVs) at three curve points. After that, the two types of speed differences are calculated: the differential of 85th percentile speed (ΔV85) and 85th percentile speed differential (Δ85V). The backward stepwise regression (BSR) technique was used on the collected speed data to develop the operating speed increment and decrement models. The results revealed that the curve geometric variables like curve radius, deflection angle, curve length, and tangent length significantly influence the drivers' speed choice behavior passing through the horizontal curves. Besides, for all three vehicle types, speed increments and decrement models ΔV85 underestimated Δ85V by 3 to 13 km=h [ABSTRACT FROM AUTHOR]

Tectonic activities and catastrophic flood events significantly assist to the process of channel avulsion and formation of river cutoffs on alluvial floodplain. The principal objectives of this research are (i) to examine the mechanism and causes of neck cutoff formation of river Raidak-1, India applying geospatial techniques, old maps and bank facies (1955–2019) and (ii) to investigate the dynamics of meander channel geometry using fluvio-hydrological techniques. Geospatial techniques and field based bank facies analysis have been used in this study. The result showed that the river channel has been significantly shifted (during the time span 1955–2019) owing to lateral channel migration resulting into formation of several neck cutoffs on the floodplain. Meander geometry study revealed that radius of curvature, meander wavelength, meander amplitude and meander belt width have been fluctuated during the entire study periods. The threshold value (less than 5°) of apex angle of two tangents at meander loop and neck distance (less than 1 km) helps to form regular neck cutoffs. The results show that high sinuosity, threshold value of meander loops; major flood events, high discharge and non-cohesive bank materials are responsible for the development of neck cutoffs. Moreover, probable sites of future cutoff formation have also been identified. Therefore, this study would give proper insights for river management approach particularly on dynamic Himalayan foreland basin, India. [ABSTRACT FROM AUTHOR]

The present study used bore-well litholog data from six locations (Badampora, Telbal, Cheshmashai, Batwara, Karannagar and Bemina) to map the aquifers and its possible geometry in parts of Srinagar and Ganderbal districts, Kashmir valley, India. From the available data, a fence diagram was generated that depicted the occurrence of a 2–32 m thick upper alluvial layer of regional scale underlain by a 2–10 m thick sandy-silt horizon. Underlying this, a regional sandy horizon varying in thickness from 3 m (Telbal and Batwara) to 11 m (Bemina) is present at a depth of 7 m (at Badampora) to 32 m (at Bemina) below the ground level. The sandy stratum is followed by a number of granular horizons comprising alternate coarser sediments with clay as matrix at varying depths. Except the sandy stratum, the other litho-horizons/aquifers indicated heterogeneity and pinching character with a significant variation in nature and geometry from place to place both vertically and horizontally, thereby leading to wide variation in the water availability. Overall, the sub-surface horizons exhibit gradation from coarse detrital sediments (gravel, pebble, boulder and coarse sand) in NE-NW parts to fine sediments (clay, silt, and fine sand) in SE-SW parts of the area. The sandy stratum along with the overlying sandy silt horizon overlain by a regional clay blanket is probably acting as a single aquifer system providing a significant and potential groundwater resource in the area. The water bearing horizons in the upper sub-surface levels exists essentially under unconfined conditions while at deeper sub-surface levels water bearing aquifers exist under confined to semi-confined conditions. The general groundwater movement originates from N-NE upland areas towards S-SW lowland areas, almost replicating the local topography and the general slope of the area. Furthermore, the chemical quality analysis suggested that the groundwater is safe for drinking purposes and suitable for agricultural uses in this area. [ABSTRACT FROM AUTHOR]

A comprehensive Ground Penetrating Radar (GPR) profiling with high resolution was done and complemented with total station surveys along an active faults in the South Andaman Island (near Bathubasti) to reveal the sub-surface fault geometry and trends in tectonic deformation in shallow stratigraphy. The surface manifestation of deformation along the investigated active faults is expressed in the form of explicit tectonic scarps of various levels related to persistent tectonic uplift of the area and frontal scarps expressed in younger sediments were meticulously examined with GPR profiling. The surface displacement (scarp height) was calculated by using high resolution GPR data and total station data that may be correlated to the vertical displacement component of palaeoseismic faulting. Two active fault sites were carefully chosen for the systematic profiling with high resolution GPR profiling to examine the efficacy of GPR in elucidating the complicated near surface tectonic deformation. The surface deformation of site-1 is manifested in a form of a 6 m high abrupt tectonic scarp expressed in quaternary sediments. Site-2 is piggy back basin with corresponding pop-up structures with two antithetic scarps of 10 m height each. The high resolution GPR data vividly reveals the complicated sub-surface fault geometry and tectonic deformation in the form of an inclined and distorted radar reflections upto several meters of depth in the shallow stratigraphy and upward fault termination related to the active deformation. The high resolution GPR profiling demonstrates severe near surface tectonic deformation in the form of buckling, truncation, offsetting of recent sediments and warped radar reflections suggesting the propagation of tectonic activity in a compressive stress regime whose dynamics is related to the continuous oblique subduction of Indian plate under the Burmese micro plate. [ABSTRACT FROM AUTHOR]

This study investigates the impact of a dynamic geometry environment, GeoGebra, in enabling grade 9 students to explore a geometrical task related to the Euler's line. The research subjects were grade 9 students in India and Sweden who had no prior experience of using dynamic geometry. Their approach to geometrical reasoning, argumentation and conjecture making has been analysed using Marton's theory of variation, Pea's theory of technology as amplifier and reorganizer and with Marrades and Gutiérrez categorization of proofs. Results indicate that when students of both countries worked on geometrical tasks in GeoGebra, they arrived at similar conclusions. For both groups of students, GeoGebra played the role of amplifier and reorganiser in enabling their explorations. Further, in some of the construction and dragging episodes it was observed that the four functions of variation, namely, contrast, generalisation, separation and fusion played a significant role in developing students' geometrical thinking. Results further indicate that the dynamic geometry environment (DGE) facilitated the making of conjectures and developing empirical proof. However, when it came to developing a deductive proof, students required adequate scaffolding. In general, it concluded that students perform adequately when given investigatory problems in such an environment. They learn new mathematics and learn to handle the DGE at the same time. [ABSTRACT FROM AUTHOR]

In the present study, we recorded the depth (d), aperture radius (r), chamber radius (rc) and size of the largest grinding tool (G) of 64 potholes from Subarnarekha river bed near Ghatsila, Jharkhand, India. Subsequent to the analysis, distinct control of substrates on pothole morphology became apparent. The average d/r ratio (γ) 2.07, of potholes on quartzite was significantly different from that of potholes on mica-schist. Variations of major and minor aperture radii of micaschist (60.59%) were much higher than those on quartzite (18.66%). The d-r linear law, d = Nr + M (where M = critical size of seminal depression that grows into a mature pothole and N = ratio between the rate of deepening and widening) seemed to hold good for potholes in both the substrates. Thirty four potholes on quartzite exhibited M = 20 cm, N = 1.2 explaining the faster rate of deepening than widening. Thirty potholes on mica-schist exhibited M = 4.9 cm, N = 0.67 explaining the faster rate of widening. On quartzite, potholes with d/r >2 exhibited rc > r which was absent in potholes on mica-schist. The d-G and r-G relations found in potholes on quartzite were insignificant for those on mica-schist. [ABSTRACT FROM AUTHOR]

We present a detailed account of the structural aspects of dykes from the Chotanagpur Gneissic Complex (CGC) of eastern India, in order to understand dyke-emplacement mechanisms and magma-chamber dynamics. The study area comprises two temporally distinct parts of the CGC, namely the Proterozoic CGC and the Gondwana CGC. Dykes of the Gondwana CGC are divided into two types based on their intrusion into either sandstones or basalts. The size distributions of dyke lengths and of thicknesses respectively follow a power-law and an exponential distribution. Power law explains the nonlinear functional relationship between two quantities in which one quantity varies as the power of the other. The essential properties of power-law are that it is scale-invariant and represents the universality of a problem. An exponential distribution explains that a quantity sharply decreases with respect to other quantities over a period of time. We calculate the overpressure conditions for 60 selected dykes using their aspect ratios. Calculated overpressure is utilized to estimate the depth of magma origin, which in turn is used to estimate the magnitude of maximum and minimum principal stresses. Based on this collective information, we propose a conceptual model of dyke emplacement. Consequently, the results have critical implications in understanding magma chamber dynamics. [Display omitted] • Structural aspects of dykes from the Chotanagpur Gneissic Complex (CGC), India. • Study area comprises two temporally distinct parts: Proterozoic CGC and Gondwana CGC. • Calculated overpressure conditions for 60 selected dykes using aspect ratios. • Estimated overpressure is utilized to estimate the depth of origin of magma. • Conceptual model of dyke emplacement and magma chamber dynamics proposed. [ABSTRACT FROM AUTHOR]

Abstract: The structural geometry in the Barr conglomerate and the neighboring rocks in the western flank of the Meso- to Neoproterozoic South Delhi Fold Belt indicate superposed deformation, with structures developed by horizontal dextral simple shear deformation superimposed on earlier structures formed during approximately ESE-WNW compression and subvertical maximum elongation. The first deformation produced NNE-SSW trending subvertical schistosity, and associated steeply plunging isoclinal folds, mineral lineation and pebble elongation lineation having almost downdip alignment on the schistosity surface. The second deformation produced dextral folds both on bedding and schistosity surfaces and modified the shape of the pebbles already deformed by the first deformation. On vertical sections perpendicular to the schistosity trace the pebbles show sub-ellipsoidal shape with their mean elongation direction parallel to the schistosity trace. On the horizontal section the pebbles often show asymmetrical shape and asymmetrical deflection of the schistosity surface around the pebbles. The mean elongation direction makes a small angle (2°–8°) in the counter-clockwise sense with the schistosity surface. This obliquity is due to modification of post-first-deformation sub-ellipsoidal shape by later horizontal simple shear using the schistosity surface as the movement plane. Analytical expressions are derived for the modification of an original ellipse by simple shear parallel to the long axis of the ellipse. A family of curves has been generated to depict the change in axial ratio and orientation of long axis for different initial axial ratios, and for different values of shear strain (γ). Using these curves it has been possible to factorize the total strain into two components representing the earlier compression and the later simple shear. It is noted that the computed earlier shortening strain ellipsoids are consistently in the flattening field close to the line of pure oblate ellipsoids in the Flinn plot. There is no systematic spatial control on the variation in the values of shear strain (γ), strain ellipsoid shape parameter (k), and intensity of distortion (d) as one proceeds south to north along the strike of the conglomerate. [Copyright &y& Elsevier]

The great challenge for the Government and private technical Institutions in India is to impart quality education to generate industry competent professionals. In last ten years, a number of educational institutions came into existence. If we analyze the net outcome, we find - (i) Passing out students are semi-trained (ii) Institutes are facing acute shortage of experienced faculty (iii) Employees turnover rate is alarmingly high in these institutions. (iv) The prevailing situation is chronic and it is very much possible that institutions which were born in geometric progression may vanish at much faster rate. Now, a time has come to examine the strategies and tactics with the intention of efficient allocation of scare resources to strengthen educational sector in India. In this competitive world of advanced technology where the changes and development run together, enough infrastructures has been developed in the sector and the private sector is ever willing to inject much more. The paper investigates an efficient and effective mechanism to identify resources and their allocation through graph for rigid quality assurance in Educational Sector. [ABSTRACT FROM AUTHOR]

Abstract: Naga fold thrust belt is an emerging destination for petroleum exploration in eastern India. It is a thin skinned FTB where new initiatives are being taken after a long gap of initial discoveries. In absence of sufficient drilling or quality seismic data in the southern part of the fold thrust belt, fluid pressure regimes remain largely speculative. Using the concept and the formulation for efficient coefficient of basal friction, we have revisited the method and concept of pressure-dependent Coulomb wedge theory for thin skinned thrust belts for deriving the fluid pressure ratio in Naga fold thrust belt. The efficient coefficient of basal friction on the decollement and the fluid ratio of Naga fold thrust belt are estimated to be 0.22 and 0.85 respectively. This indicates an overpressure situation in the wedge. This method of estimating basal friction and fluid pressure is more case-specific and can be obtained from the data of thrust initiation angle and thrust spacing. [Copyright &y& Elsevier]

Abstract: This paper addresses a distinctive event bedset encased by coastal erg-margin deposits, at a preferred stratigraphic level near the base of the Neoproterozoic Upper Bhander Sandstone in central India. The bedset is composed of couplets of sandstone beds that exhibit incisive amalgamation although they differ in geometry, structures (at soles, within and at tops of beds), vertical grain-size variation as well as palaeocurrent pattern and direction. The wide extent of the bedset is evident from several exposures spread over a distance of more than 50km roughly in strike-parallel direction. Flow and depositional dynamics interpreted from the coupled event beds are more consistent with a tsunami origin than alternative palaeogeography-compatible models of climate-induced storm, flash flood or accentuated tide deposits. A palaeotsunamiite model is thus discussed, with separate incoming and outgoing components. Considering the overall depositional setting to be an epeiric sea coast in an intracratonic sag basin, the relevant bedset is inferred to reflect the record of a teletsunamiite; it would also be one of the very few Precambrian tsunamiites known so far. Exceptional preservation of this possible tsunamiite was facilitated by sheltered deposition behind the backshore zone and the berm, as well as by rapid burial by wind-deflated sands and advancing aeolian dunes. [Copyright &y& Elsevier]

In modern societies the world over, there is a strong emphasis on the provision of good quality Science, Technology and Mathematics (STM) education. Mathematics plays a pivotal role in STM education. Mathematics enhances creative and logical reasoning about problems in our inherently geometric world. Students' mathematical competencies have been closely linked to their levels of geometric understanding. Various studies have documented that many students encounter difficulties and performed poorly in both middle and high schools geometry classrooms. Data from various studies indicate that the performance of Indian high school students in mathematics is mediocre. This suggests that students lack higher order thinking skills. The average Indian achievement in geometry is unsatisfactory. Moreover, researches show a decline in students' motivation toward mathematics. Among the variables that affect student learning, researchers have suggested that the teacher has the greatest impact on students' motivation , mathematics learning and the primary source for justifying instructional decisions noted by the teachers was textbooks. [ABSTRACT FROM AUTHOR]

Abstract: The horizontal compressive stress orientations for Mandapeta field in Krishna-Godavari (K-G) basin had been calculated from borehole breakout data using four-arm dipmeter caliper logs. The minimum horizontal stress magnitude for Mandapeta field was calculated from pore pressure data using poroelastic equation. Three-dimensional (3-D) stress modeling using finite element analyses has been carried out for layered sediments and faulted layered sediments in the Mandapeta sub-basin. The length and width of the models are chosen as 5 km and 2 km respectively. Vertical depths of models are considered for sediments at depth 2 km to 5 km. This paper presents a numerical study of stress distributions (contours and trajectories) around fault models of layered geometries, submitted to overburden and unequal horizontal compressive loads. Reorientation and magnitude variation of in-situ stresses near faults and stress discontinuities across faults are observed. Changes in the stress patterns are observed at the interfaces between sediments due to faulting and sediment-basement layers due to contrast in elastic constants. Remarkable stress gradients are observed between the sediment and basement. Magnitudes of normal component of stress decrease near the faulting whereas shear stress magnitudes increase at the faulting site. There is increase of horizontal principal stresses in the downthrown faulted layers. The maximum horizontal principal stress rotates about 90° just adjacent to the fault. Fluid flow at depth of oil reservoir could be indirectly influenced by the stress contours and by geometries of the stress trajectories. Fluid migration in low permeability reservoir may occur in response to mean stress gradients induced by the tectonic loading. The areas of high mean stress gradient are located at the interface between sediment and basement whereas the areas of low mean stress gradient is exactly coinciding with the areas of upper sediments. [Copyright &y& Elsevier]

Abstract: A common feature of convergent plate boundaries is the self-organization of strain, exhumation and topography along discrete, arcuate boundaries. Deviations from this geometry can represent first-order changes in stress applied at a plate boundary that must affect how strain is partitioned within the interior of an orogen. The simplicity of the Himalayan fold and thrust belt seen along its central portion breaks down along the eastern extremity of the arc where the 400 km-long Shillong Plateau has developed. This change in strain partitioning affects nearly 25% of the arc and has not previously been considered to be important to the orogen''s development. New low-temperature thermochronometry data suggest this structure initiated in mid to late Miocene time, significantly earlier than was previously estimated from the sedimentary record alone. Development of the Shillong Plateau may be linked to a number of kinematic changes within the Himalayan and Burman collision zones that occur at the same time. These events include the onset of E–W extension in central Tibet, eastward expansion of high topography of the Tibetan Plateau, onset of rotation of crustal fragments in southeastern Tibet, and re-establishment of eastward subduction beneath the Indo-Burman ranges. We suggest that the coincidence of these tectonic events is related to the ‘dismemberment’ of the eastern Himalayan arc, signifying a change in regional stress applied along the India–Eurasia–Burma plate boundaries. Discrepancies between vertical long-term faulting rates and geodetically derived far-field convergence rates suggest that the collisional boundary in the eastern Himalayan system may be poorly coupled due to introduction of oceanic and transitional crust into the eastern plate boundary. The introduction of dense material into the plate boundary late in the orogen''s history may explain regional changes in the strain field that affect not only the Himalaya, but also the deformation field more than 1000 km into the Tibetan Plateau. [Copyright &y& Elsevier]

Geoelectrical techniques have been used to define the geometry of aquifer systems in the Pathri-Rao watershed situated in the piedmont zone of the Himalayan foothill region, Uttarakhand, India. This has been done by integrating the results of dc resistivity and electromagnetic data recorded in the area. Two-dimensional resistivity imaging was carried out to define the horizontal and vertical geometry of the aquifer system and to infer the local groundwater flow condition. On the basis of resistivity values it was found that shallow and deep aquifers have different degrees of interaction in the area. The study demonstrates the versatility of geoelectrical techniques. [ABSTRACT FROM AUTHOR]

Tanpura is a multi-stringed accompanying drone instrument extensively used in classical music in India. The instrument is plucked by finger. We know that jitter, shimmer and complexity perturbations (CP) are found also in tanpura signals. The source of origin of these perturbations was reported to be related to some sort of nonlinearity associated with the strings and their mode of attachment. The objective of the present study is to see in what way fractal-dimensional analysis may be helpful to relate the apparent nonlinearity and also if there is any relation of these dimensions with different part of the signals like attack time, quasi-steady state and the decay. In the paper fractal dimension, D0 and generalized dimensions, D2 to D10 and their dynamic behavior over time are studied for 15 tanpuras having four strings each, tuned to Pa (5th note), Sa (tonic), Sa (tonic) and Sa′ (lower octave tonic). The obeying of power law indicates nonlinearity in the production source system. The presence of multifractality is studied through an examination of relationship between q and Dq and the functional relationship between Dqs. [ABSTRACT FROM AUTHOR]

Transpressional deformation in ductile shear zones may be analyzed by simultaneous wall-parallel simple shear (with strain rate γ•=γxy•) along with three-dimensional coaxial deformation (with strain rates εx•, εy• and εz•). Several types of transpression may be distinguished on the basis of relative values of strain-rate ratios εx•/γ• (=a), εy•/γ• (=b) and εz•/γ• (=c). It is possible to identify the nature of transpressional deformation from a detailed analysis of shear zone structures. In the Phulad shear zone of Rajasthan, India, evidence of general flattening, a thrusting sense of shear, occurrence of transport-parallel stretching lineation, frequent occurrence of sheath folds with apical direction parallel to the stretching lineation and occurrence of U-shaped lineation patterns indicate that the deformation was transpressional, with b/a ratio ranging between -1 and -2. The bulk deformation was not dominated by simple shear, but involved both simple and pure shear, with extrusion along the transport direction much greater than along the vorticity vector. Rotation of long tectonic clasts caused reorientation of monoclinic rolling structures, so that strongly monoclinic structures, with opposite senses of asymmetry in different domains, appear on subhorizontal outcrops parallel to the vorticity vector, although the component of simple shear is zero on these surfaces. [Copyright &y& Elsevier]

Presents two exams taken by Indian mathematician Srinivasa Ramanujan. Matriculation Exam of Madras University taken by Ramanujan in 1903 which consisted of arithmetic, geometry and algebra; First Arts Exam at Pachaiyappa College in 1907 which consisted of algebra, trigonometry and geometry.

The Wide-Field Sensor (WiFS) on board Indian Remote Sensing Satellites (IRS-1C, IRS-P3 and IRS-1D) has a wide swath (~810 km) and is thus able to provide high repetivity (5/3 days) data acquired from different orbits. The impact of variable viewing geometry from WiFS on crop reflectance was investigated for Delhi (77.2°E and 28.58°N) for all 122 possible acquisitions by IRS-1C during 1997. Using the SAIL simulation model, top-of-canopy red and near-infrared reflectances were simulated for partial and closed crop canopies over soils of different brightness. Results show significant variations in red and near-infrared reflectances. The effects are higher in partial canopies, and they are observed in Normalized Difference Vegetation Index (NDVI) also. For partial canopy, the seasonal variations with solar zenith angle are also significant. For closed canopy, these variations are less, and computed NDVI is relatively insensitive to viewing geometry. [ABSTRACT FROM AUTHOR]

Balanced cross section is a technique that allows derivation of geometrically and kinematically valid subsurface structural geometry. Jeypore anticline is thought to be ramp anticline of the Naga Thrust, which is the frontal-most thrust in the Assam-Arakan Fold-Thrust Belt (AA-FTB), NE India. The AA-FTB is formed as a consequence of Tertiary collision between Indian plate and West Burma plate. In NE India, most of the oil fields have been discovered in the foreland, i.e., in the footwall of Naga Thrust. In the hangingwall very few discoveries have been made – Digboi and Kusijan are the better known oil fields. India's oldest and still producing Digboi oil field, discovered in 1889, occurs in the north-eastern part of Jeypore anticline (locally called Digboi anticline) whereas the Kusijan oil field occurs further towards southwest. In this contribution, we report eight balanced cross sections across Jeypore anticline in both Digboi oil field and adjacent Kusijan oil field areas.Constant bed length/area has been assumed for all the sections for each of the Formations. The cross sections show co-relatable ramp anticlines above the Naga Thrust. The ramp-anticlines are modelled as fault-propagation fold. They undergo high-angle breakthrough in the Digboi oil field area but in the Kusijan oil field area and in remaining Jeypore anticline, the breakthroughs are very close to synclinal axial planes giving rise to snake-head anticlines. In the Digboi region, forelimb thinning is applied during slip along the breakthrough to match with the surface data; however, sections across Kusijan field maintained constant stratigraphic thicknesses during thrust-related deformation. In the Kusijan area, hanging wall imbrication of Naga Thrust is observed in the cross sections, leading to anticline-syncline-anticline folds. This imbrication is blind and rejoining splay on the Naga Thrust. All the eight cross sections have detachment at the same stratigraphic level (within Tikak Parbat Fm.) but the depth to detachment varies from 4.2 km in the Kusijan field to 5.2 km in the Digboi field. A comparison among the eight cross sections shows variations in shortening, displacement along the detachment and dimensions of fault ramp. The shortening amount in SW end of Jeypore anticline up to Kusijan field is 31% to 36% while in the NE end of Jeypore anticline i.e. in Digboi field it is 25% to 27%. This differential shortening may be responsible for the "Assam Railroad Tear Fault" separating the two areas. The slip along the detachment varies from 5.8 km to 6.4 km in Digboi field; while 7.6 km to 9.4 km in the remaining Jeypore anticline. This slip brings late Oligocene Tikak Parbat Formation up to the present day surface topography. Towards the hinterland of AA-FTB much older Formations are exposed indicating deeper detachment and/or higher slip along the detachment surfaces. We are in the process of extending section balancing from the Naga Thrust to hinterland in order to understand the structural evolution of this collision belt as well as the hydrocarbon prospectivity in the hinterland of the Naga Thrust. [ABSTRACT FROM AUTHOR]

The article focuses on a novel arrangement of carbon nanotubes--a macroscopic, hollow cylinder. This new geometry which was created by researchers at Polytechnic Institute and Banaras Hindu University, India, could lead to more applications for carbon nanotubes, including their use in separations. A researcher said that the investigators' objective behind the growth of bulk cylinders of carbon nanotubes was to find new applications, which is not possible without definite shape. The cylinder was found to be chemically inert and therefore could be used for filtration applications.