Science.gov

Sample records for negative-index material design

  1. Wave propagation in negative index materials

    NASA Astrophysics Data System (ADS)

    Aylo, Rola

    Properties of electromagnetic propagation in materials with negative permittivities and permeabilities were first studied in 1968. In such metamaterials, the electric field vector, the magnetic field vector, and the propagation vector form a left hand triad, thus the name left hand materials. Research in this area was practically non-existent, until about 10 years ago, a composite material consisting of periodic metallic rods and split-ring resonators showed left-handed properties. Because the dimension of the constituents of the metamaterial are small compared to the operating wavelength, it is possible to describe the electromagnetic properties of the composite using the concept of effective permittivity and permeability. In this dissertation, the basic properties of electromagnetic propagation through homogenous left hand materials are first studied. Many of the basic properties of left hand materials are in contrast to those in right hand materials, viz., negative refraction, perfect lensing, and the inverse Doppler effect. Dispersion relations are used to study wave propagation in negative index materials. For the first time to the best of our knowledge, we show that a reduced dispersion relation, obtained from the frequency dependence of the propagation constant by neglecting a linear frequency dependent term, obeys causality. Causality of the propagation constant enables us to use a novel and simple operator formalism approach to derive the underlying partial differential equations for baseband and envelope wave propagation. Various tools for understanding and characterizing left-handed materials are thereafter presented. The transfer matrix method is used to analyze periodic and random structures composed of positive and negative index materials. By random structures we mean randomness in layer position, index of refraction, and thickness. As an application of alternating periodic negative index and positive index structures, we propose a novel sensor using

  2. Material parameter retrieval procedure for general bi-isotropic metamaterials and its application to optical chiral negative-index metamaterial design.

    PubMed

    Kwon, Do-Hoon; Werner, Douglas H; Kildishev, Alexander V; Shalaev, Vladimir M

    2008-08-01

    A chiral optical negative-index metamaterial design of doubly periodic construction for the near-infrared spectrum is presented. The chirality is realized by incorporating sub-wavelength planar silver-aluminasilver resonators and arranging them in a left-handed helical (i.e., stair-step) configuration as a wave propagates through the metamaterial. An effective material parameter retrieval procedure is developed for general bi-isotropic metamaterials. A numerical design example is presented and the retrieved effective material parameters exhibiting a negative index of refraction are provided. PMID:18679454

  3. Microwave Focusing Using Negative Index of Refraction Materials

    NASA Astrophysics Data System (ADS)

    Brock, Jeffrey; Houck, Andrew; Chuang, Isaac

    2003-03-01

    We present experimental results testing the theoretical prediction that a flat slab of negative index material can act as a perfect lens, focusing propagating waves. Our data gives two-dimensional profiles of the electromagnetic field transmitted from a 10 GHz point source in a 2D waveguide through composite wire and split-ring resonator rectangular prisms. Prior experiments show that these structures have a negative index of refraction in a narrow frequency regime. We measure transmission through prisms of various thicknesses in both the negative index and positive index regimes, and observe a spatial concentration of power when the material has a negative index that is absent in the positive index measurements.

  4. Electromagnetic field energy density in homogeneous negative index materials.

    PubMed

    Shivanand; Webb, Kevin J

    2012-05-01

    An exact separation of both electric and magnetic energies into stored and lost energies is shown to be possible in the special case when the wave impedance is independent of frequency. A general expression for the electromagnetic energy density in such a dispersive medium having a negative refractive index is shown to be accurate in comparison with numerical results. Using an example metamaterial response that provides a negative refractive index, it is shown that negative time-averaged stored energy can occur. The physical meaning of this negative energy is explained as the energy temporarily borrowed by the field from the material. This observation for negative index materials is of interest when approaching properties for a perfect lens. In the broader context, the observation of negative stored energy is of consequence in the study of dispersive materials. PMID:22712096

  5. On the resolution of lenses made of a negative-index material

    SciTech Connect

    Petrin, A B

    2013-09-30

    Resolution of the lenses made of a negative-index material is considered. It is shown that the super-resolution concept is untenable and the possibility of obtaining a perfect image on its own eventually contradicts Maxwell's equations in vacuum. It is also shown that known limitations of the diffraction theory on resolution of optical instruments hold true for the resolution of lenses of a negative-index material, in particular, the resolution of a Veselago lens. (nanogradient dielectric coatings and metamaterials)

  6. Optical propagation through a homogeneous mixture of positive and negative index materials

    NASA Astrophysics Data System (ADS)

    Aylo, Rola; Banerjee, Partha P.; Nehmetallah, George

    2008-08-01

    Metamaterials, which maybe the answer to "perfect lensing", are often fabricated as a periodic array of elements which exhibit negative refractive index or negative permeability/permittivity. In this work, we outline and illustrate a framework that can model propagation through a homogeneous and random mixture of positive and negative index materials. We achieve this by using a matrix-based multilayered approach, and a random sequence of positive and negative index materials, and by incorporating all possible combinations of such layers. Plane wave propagation is investigated, and aggregated transmittivity is calculated. We show that near-zero net refractive index maybe achieved through a random homogeneous mixture of positive and negative index materials.

  7. Experimental verification of the inverse Doppler effect in negative-index material

    NASA Astrophysics Data System (ADS)

    Feng, Lie; Chen, Jiabi; Wang, Yan; Geng, Tao; Zhuang, Songlin

    2010-10-01

    μResearch of negative-index material (NIM) is a very hot developing research field in recent years. NIM is also called left-handed material (LHM), in which the electric field [see manuscript], the magnetic field [see manuscript] and the wave vector [see manuscript] are not composed of a set of right-handed coordinates but a set of left-handed coordinates. Thus the action of electromagnetic waves in both left-handed material and right-handed material is just the opposite, for instance, the negative refraction phenomenon, the inverse Doppler effect and so on. Here we report the explicit result of the inverse Doppler effect through a photonic crystal (PC) prism at 10.6m wavelength for the first time, and the result we get from the experiment is much similar to the theoretical analysis we have deduced before. During the experiment, the CO2 laser is used as a light source, and the PC prism is used as a sample, which can move a tiny distance (1mm) uniformly with a translating stage. Based on the method of optical heterodyne, we let the emergent light from the output surface of PC prism and the reference light from light source interfere at the surface of the detector. When the translating stage moves towards the detector, the optical paths in the PC prism will be changed, and then the Doppler frequency shift will be generated. Though several different samples have been tested repeatedly, the results we get are extraordinarily similar. So we can be sure that the inverse Doppler effect really exists in the NIM at optical frequencies. To our best knowledge, this is the only experimental verification of the inverse Doppler effect in the NIM at optical frequencies at home and aboard.

  8. Investigation of negative index in dispersive, chiral materials via contra-propagating velocities under second-order dispersion (GVD)

    NASA Astrophysics Data System (ADS)

    Chatterjee, Monish R.; Algadey, Tarig

    2013-09-01

    Negative refractive index arises typically in metamaterials via multiple routes. One such avenue is the condition where the Poynting vector of the electromagnetic wave is in opposition to the group velocity in the material. An earlier work along this route in a chiral material led to the well-known result of requiring very large (non-realizable) chirality. Thereafter, a combination of chirality together with first-order dispersion was examined using plane wave electromagnetic analysis. To arrive at the conclusions in that approach, the three wave velocities (energy, group and phase) were derived under first-order dispersion in permittivity, permeability and chirality. Negative index in this approach was established under the condition of contra-propagating group and phase velocities. Regions of negative index were found analytically by assuming standard dispersive models (such as Condon). In this paper, we will re-visit the negative index problem under higher-order dispersion. In addition, we will re-examine the plane wave propagation model under parametric dispersion where each material parameter (ɛ, μ, κ) is dispersively expanded up to the second order in frequency. Such a physical effect may be traced to group velocity dispersion (GVD) in the material. Field solutions are then obtained under the GVD effect, and extended to the evaluation of the energy, phase and group velocities.

  9. Dispersion, spatial growth rate, and start current of a Cherenkov free-electron laser with negative-index material

    SciTech Connect

    Wang, Yuanyuan; Wei, Yanyu; Jiang, Xuebing; Tang, Xianfeng; Shi, Xianbao; Gong, Yubin; Li, Dazhi; Takano, Keisuke; Nakajima, Makoto; Feng, Jinjun; Miyamoto, Shuji

    2015-08-15

    We present an analysis of a Cherenkov free-electron laser based on a single slab made from negative-index materials. In this system, a flat electron beam with finite thickness travelling close to the surface of the slab interacts with the copropagating electromagnetic surface mode. The dispersion equation for a finitely thick slab is worked out and solved numerically to study the dispersion relation of surface modes supported by negative-index materials, and the calculations are in good agreement with the simulation results from a finite difference time domain code. We find that under suitable conditions there is inherent feedback in such a scheme due to the characteristics of negative-index materials, which means that the system can oscillate without external reflectors when the beam current exceeds a threshold value, i.e., start current. Using the hydrodynamic approach, we setup coupled equations for this system, and solve these equations analytically in the small signal regime to obtain formulas for the spatial growth rate and start current.

  10. Dispersion, spatial growth rate, and start current of a Cherenkov free-electron laser with negative-index material

    NASA Astrophysics Data System (ADS)

    Wang, Yuanyuan; Wei, Yanyu; Li, Dazhi; Takano, Keisuke; Nakajima, Makoto; Jiang, Xuebing; Tang, Xianfeng; Shi, Xianbao; Gong, Yubin; Feng, Jinjun; Miyamoto, Shuji

    2015-08-01

    We present an analysis of a Cherenkov free-electron laser based on a single slab made from negative-index materials. In this system, a flat electron beam with finite thickness travelling close to the surface of the slab interacts with the copropagating electromagnetic surface mode. The dispersion equation for a finitely thick slab is worked out and solved numerically to study the dispersion relation of surface modes supported by negative-index materials, and the calculations are in good agreement with the simulation results from a finite difference time domain code. We find that under suitable conditions there is inherent feedback in such a scheme due to the characteristics of negative-index materials, which means that the system can oscillate without external reflectors when the beam current exceeds a threshold value, i.e., start current. Using the hydrodynamic approach, we setup coupled equations for this system, and solve these equations analytically in the small signal regime to obtain formulas for the spatial growth rate and start current.

  11. Backward phase-matching for nonlinear optical generation in negative-index materials.

    PubMed

    Lan, Shoufeng; Kang, Lei; Schoen, David T; Rodrigues, Sean P; Cui, Yonghao; Brongersma, Mark L; Cai, Wenshan

    2015-08-01

    Metamaterials have enabled the realization of unconventional electromagnetic properties not found in nature, which provokes us to rethink the established rules of optics in both the linear and nonlinear regimes. One of the most intriguing phenomena in nonlinear metamaterials is 'backward phase-matching', which describes counter-propagating fundamental and harmonic waves in a negative-index medium. Predicted nearly a decade ago, this process is still awaiting a definitive experimental confirmation at optical frequencies. Here, we report optical measurements showing backward phase-matching by exploiting two distinct modes in a nonlinear plasmonic waveguide, where the real parts of the mode refractive indices are 3.4 and -3.4 for the fundamental and the harmonic waves respectively. The observed peak conversion efficiency at the excitation wavelength of ∼780 nm indicates the fulfilment of the phase-matching condition of k(2ω) = 2k(ω) and n(2ω) = -n(ω), where the coherent harmonic wave emerges along a direction opposite to that of the incoming fundamental light.

  12. Superconducting artificial materials with a negative permittivity, a negative permeability, or a negative index of refraction

    NASA Astrophysics Data System (ADS)

    Ricci, Michael Christopher

    Artificial materials are media made of inclusions such that the sizes and spacing of the inclusions is much smaller than the incident electromagnetic radiation. This allows a medium to act as an effective bulk medium to electromagnetic radiation. Artificial materials can be tailored to produce desired values of the permittivity, permeability, and index of refraction at specific frequencies. The applications of this tailoring include electromagnetic cloaking, and, theoretically, subwavelength imaging resolution. However, the success of these applications depends on their sensitivity to loss. This research uses superconducting niobium (Nb) metals to create arrays of wires, split-ring resonators, and a combination of wires and split-ring resonators, with very low loss. These arrays are used to investigate properties of a medium with an index of refraction that contains a bandwidth of frequency where the real part is negative. The Nb wire arrays produce a frequency bandwidth with a negative real part of the permittivity, while the Nb split-ring resonators produce a frequency bandwidth with a negative real part of the permeability. The combination of Nb wires and Nb split-ring resonators creates an artificial medium with a negative real part of the index of refraction. The electromagnetic transmission of the wires, split-ring resonators, and combination medium is measured in a waveguide as a function of frequency, and models of the permittivity and permeability are used to fit this data. For a single Nb split-ring resonator, the change in the resonant frequency and quality factor with temperature is measured and fit with a two-fluid model of superconductivity. The change in the resonant frequency and quality factor with an applied dc H field and applied power is also measured and compared to, respectively, magneto-optical imaging and laser scanning photoresponse measurements. Bianisotropy and perturbations in the resonant frequency are investigated, and simulated with

  13. Properties of Defect Modes in Periodic Lossy Multilayer with Negative-Index-Materials

    NASA Astrophysics Data System (ADS)

    Alireza, Aghajamali; Mahmood, Barati

    2013-07-01

    Employing the characteristic matrix method, this study investigates transmission properties of one-dimensional defective lossy photonic crystals composed of negative and positive refractive index layers with one lossless defect layer at the center of the crystal. The results of the study show that as the refractive index and thickness of the defect layer increase, the frequency of the defect mode decreases. In addition, the study shows that the frequency of the defect mode is sensitive to the incidence angle, polarization, and physical properties of the defect layer, but it is insensitive to the small lattice loss factor. The peak of the defect mode is very sensitive to the loss factor, incidence angle, polarization, refractive index, and thickness of the defect layer. This study also shows that the peak and the width of the defect mode are affected by the numbers of the lattice period and the loss factor. The results can lead to designing new types of narrow filter structures and other optical devices.

  14. Low-loss optical metamaterials: Homogeneous material systems for negative index metamaterials and novel loss suppression method based on bichromatic irradiation

    NASA Astrophysics Data System (ADS)

    Ait-El-Aoud, Yassine

    The main emphasis of this work is to develop low loss homogeneous optical negative index metamaterials. The work is involved in the fabrication and characterization of homogeneous negative index material based on magnetic semiconductors, then the implementation of a novel loss suppression mechanism on optical materials, including the negative index metamaterials. As part of the first effort, we introduce a novel class of isotropic homogeneous negative index material based on magnetic semiconductors. Specifically, Chromium doped Indium Oxide (ICO) was used to explore this idea. The main mechanism behind the negative index effect of this material is based on the coexistence of plasmon (the negative permittivity in Indium Oxides) and magnon (Chromium exhibits ferromagnetic behavior leading to a negative magnetic permeability) resonances. A novel fabrication technique for Chromium doped Indium Oxide, In(2-- x)CrxO(3--delta) , thin films was developed. The samples are fabricated by using the RF/DC magnetron deposition method at room temperature, with low stoichiometric oxygen deficiency and doping concentration of 3%. The measured electric and magnetic properties of ICO ferromagnetic thin films agree with the previously reported data. The extracted negative refractive index band parameters of ferromagnetic ICO thin films are found to be consistent with the theoretical predictions, as well as extracted parameters. Direct experimental evidence of the negative refraction effect was also demonstrated. The second part of the work is on a novel experimental method to reduce the losses in optical materials (including negative metamaterials) by introducing the theory of Bichromatic Loss Suppression, or simply the parametric two-wave coherent coupling technique. These optical losses restrict many interesting applications and effects in several systems including negative refractive index metamaterials, such as sub-wavelength imaging using the "perfect lens" (super- and hyperlens

  15. Focus modulation of cylindrical vector beams through negative-index grating lenses

    NASA Astrophysics Data System (ADS)

    Wang, Shengming; Xu, Ji; Zhong, Yi; Ren, Rong; Lu, Yunqing; Wan, Hongdan; Wang, Jin; Ding, Jianping

    2016-08-01

    A cylindrically symmetric negative-index grating lens composed of unitary material is proposed as an effective method to modulate the focusing of cylindrical vector beams (CVBs). The grating parameters are designed to obtain an appropriate negative index, and the lens profile is tailored to realize the constructive interference. The plano-concave lens is parameterized to achieve desired focal length and the plano-cone lens is proposed to obtain large depth of focus. An optical needle is generated with radially polarized incidence, and an optical tube is achieved with incidence of azimuthal polarization. Moreover, the presented modulation methods can be applied for any arbitrary polarized CVBs. This work offers a more flexible and effective approach to design negative-index lenses for subwavelength focusing of CVBs, which has potential application value in related areas, such as optical trapping, and other nano-optics fields.

  16. Structures with negative index of refraction

    DOEpatents

    Soukoulis, Costas M.; Zhou, Jiangfeng; Koschny, Thomas; Zhang, Lei; Tuttle, Gary

    2011-11-08

    The invention provides simplified negative index materials (NIMs) using wire-pair structures, 4-gap single ring split-ring resonator (SRR), fishnet structures and overleaf capacitor SRR. In the wire-pair arrangement, a pair of short parallel wires and continuous wires are used. In the 4-gap single-ring SRR, the SRRs are centered on the faces of a cubic unit cell combined with a continuous wire type resonator. Combining both elements creates a frequency band where the metamaterial is transparent with simultaneously negative .di-elect cons. and .mu.. In the fishnet structure, a metallic mesh on both sides of the dielectric spacer is used. The overleaf capacitor SRR changes the gap capacities to small plate capacitors by making the sections of the SRR ring overlap at the gaps separated by a thin dielectric film. This technique is applicable to conventional SRR gaps but it best deploys for the 4-gap single-ring structures.

  17. Direct observation of negative-index microwave surface waves.

    PubMed

    Dockrey, J A; Horsley, S A R; Hooper, I R; Sambles, J R; Hibbins, A P

    2016-01-01

    Waves propagating in a negative-index material have wave-front propagation (wavevector, k) opposite in direction to that of energy flow (Poynting vector, S). Here we present an experimental realisation at microwave frequencies of an analogous surface wave phenomenon whereby a metasurface supports a surface mode that has two possible wavevector eigenstates within a narrow band of frequencies: one that supports surface waves with positive mode index, and another that supports surface waves with negative mode index. Phase sensitive measurements of the near-field of surface waves across the metasurface show the contrasting spatial evolution of the two eigenstates, providing a unique opportunity to directly observe the negative-index phenomenon. PMID:26903284

  18. Direct observation of negative-index microwave surface waves

    PubMed Central

    Dockrey, J. A.; Horsley, S. A. R.; Hooper, I. R.; Sambles, J. R.; Hibbins, A. P.

    2016-01-01

    Waves propagating in a negative-index material have wave-front propagation (wavevector, k) opposite in direction to that of energy flow (Poynting vector, S). Here we present an experimental realisation at microwave frequencies of an analogous surface wave phenomenon whereby a metasurface supports a surface mode that has two possible wavevector eigenstates within a narrow band of frequencies: one that supports surface waves with positive mode index, and another that supports surface waves with negative mode index. Phase sensitive measurements of the near-field of surface waves across the metasurface show the contrasting spatial evolution of the two eigenstates, providing a unique opportunity to directly observe the negative-index phenomenon. PMID:26903284

  19. Low-loss negative index metamaterials for X, Ku, and K microwave bands

    NASA Astrophysics Data System (ADS)

    Lee, David A.; Vedral, L. James; Smith, David A.; Musselman, Randall L.; Pinchuk, Anatoliy O.

    2015-04-01

    Low-loss, negative-index of refraction metamaterials were designed and tested for X, Ku, and K microwave frequency bands. An S-shaped, split-ring resonator was used as a unit cell to design homogeneous slabs of negative-index metamaterials. Then, the slabs of metamaterials were cut unto prisms to measure experimentally the negative index of refraction of a plane electromagnetic wave. Theoretical simulations using High-Frequency Structural Simulator, a finite element equation solver, were in good agreement with experimental measurements. The negative index of refraction was retrieved from the angle- and frequency-dependence of the transmitted intensity of the microwave beam through the metamaterial prism and compared well to simulations; in addition, near-field electromagnetic intensity mapping was conducted with an infrared camera, and there was also a good match with the simulations for expected frequency ranges for the negative index of refraction.

  20. Low-loss negative index metamaterials for X, Ku, and K microwave bands

    SciTech Connect

    Lee, David A.; Vedral, L. James; Smith, David A.; Pinchuk, Anatoliy O.; Musselman, Randall L.

    2015-04-15

    Low-loss, negative-index of refraction metamaterials were designed and tested for X, Ku, and K microwave frequency bands. An S-shaped, split-ring resonator was used as a unit cell to design homogeneous slabs of negative-index metamaterials. Then, the slabs of metamaterials were cut unto prisms to measure experimentally the negative index of refraction of a plane electromagnetic wave. Theoretical simulations using High-Frequency Structural Simulator, a finite element equation solver, were in good agreement with experimental measurements. The negative index of refraction was retrieved from the angle- and frequency-dependence of the transmitted intensity of the microwave beam through the metamaterial prism and compared well to simulations; in addition, near-field electromagnetic intensity mapping was conducted with an infrared camera, and there was also a good match with the simulations for expected frequency ranges for the negative index of refraction.

  1. A single-layer wide-angle negative-index metamaterial at visible frequencies

    NASA Astrophysics Data System (ADS)

    Burgos, Stanley P.; de Waele, Rene; Polman, Albert; Atwater, Harry A.

    2010-05-01

    Metamaterials are materials with artificial electromagnetic properties defined by their sub-wavelength structure rather than their chemical composition. Negative-index materials (NIMs) are a special class of metamaterials characterized by an effective negative index that gives rise to such unusual wave behaviour as backwards phase propagation and negative refraction. These extraordinary properties lead to many interesting functions such as sub-diffraction imaging and invisibility cloaking. So far, NIMs have been realized through layering of resonant structures, such as split-ring resonators, and have been demonstrated at microwave to infrared frequencies over a narrow range of angles-of-incidence and polarization. However, resonant-element NIM designs suffer from the limitations of not being scalable to operate at visible frequencies because of intrinsic fabrication limitations, require multiple functional layers to achieve strong scattering and have refractive indices that are highly dependent on angle of incidence and polarization. Here we report a metamaterial composed of a single layer of coupled plasmonic coaxial waveguides that exhibits an effective refractive index of -2 in the blue spectral region with a figure-of-merit larger than 8. The resulting NIM refractive index is insensitive to both polarization and angle-of-incidence over a +/-50∘ angular range, yielding a wide-angle NIM at visible frequencies.

  2. Sub-picosecond optical switching with a negative index metamaterial

    SciTech Connect

    Dani, Keshav M; Upadhya, Prashant C; Zahyum, Ku

    2009-01-01

    Development of all-optical signal processing, eliminating the performance and cost penalties of optical-electrical-optical conversion, is important for continu,ing advances in Terabits/sec (Tb/s) communications.' Optical nonlinearities are generally weak, traditionally requiring long-path, large-area devicesl,2 or very high-Q, narrow-band resonator structures.3 Optical metamaterials offer unique capabilities for optical-optical interactions. Here we report 600 femtosecond (fs) all-optical modulation using a fIShnet (2D-perforated metallamorphous-Si (a-Si)/metal film stack) negative-index meta material with a structurally tunable broad-band response near 1.2 {micro}m. Over 20% modulation (experimentally limited) is achieved in a path length of only 116 nm by photo-excitation of carriers in the a-Si layer. This has the potential for Tb/s aU-optical communication and will lead to other novel, compact, tunable sub-picosecond (ps) photonic devices.

  3. Symmetry breaking and optical negative index of closed nanorings

    NASA Astrophysics Data System (ADS)

    Kanté, Boubacar; Park, Yong-Shik; O'Brien, Kevin; Shuldman, Daniel; Lanzillotti-Kimura, Norberto D.; Jing Wong, Zi; Yin, Xiaobo; Zhang, Xiang

    2012-11-01

    Metamaterials have extraordinary abilities, such as imaging beyond the diffraction limit and invisibility. Many metamaterials are based on split-ring structures, however, like atomic orbital currents, it has long been believed that closed rings cannot produce negative refractive index. Here we report a low-loss and polarization-independent negative-index metamaterial made solely of closed metallic nanorings. Using symmetry breaking that negatively couples the discrete nanorings, we measured negative phase delay in our composite ‘chess metamaterial’. The formation of an ultra-broad Fano-resonance-induced optical negative-index band, spanning wavelengths from 1.3 to 2.3 μm, is experimentally observed in this structure. This discrete and mono-particle negative-index approach opens exciting avenues towards symmetry-controlled topological nanophotonics with on-demand linear and nonlinear responses.

  4. Symmetry Breaking and Optical Negative Index of Closed Nanorings

    NASA Astrophysics Data System (ADS)

    Kante, Boubacar; Park, Yong-Shik; O'Brien, Kevin; Shuldman, Daniel; Lanzillotti-Kimura, Norberto; Wong, Zi; Yin, Xiaobo; Zhang, Xiang; UC Berkeley Team

    2013-03-01

    We report the first experimental demonstration of broadband negative-index metamaterial made solely of closed metallic nanorings. Using symmetry breaking that negatively couples the discrete nanorings, we measured negative phase delay in our composite chess metamaterial. Our approach open avenues towards topological nanophotonics with on demand linear and non-linear responses.

  5. All-semiconductor negative-index plasmonic absorbers.

    PubMed

    Law, S; Roberts, C; Kilpatrick, T; Yu, L; Ribaudo, T; Shaner, E A; Podolskiy, V; Wasserman, D

    2014-01-10

    We demonstrate epitaxially grown all-semiconductor thin-film midinfrared plasmonic absorbers and show that absorption in these structures is linked to the excitation of highly confined negative-index surface plasmon polaritons. Strong (>98%) absorption is experimentally observed, and the spectral position and intensity of the absorption resonances are studied by reflection and transmission spectroscopy. Numerical models as well as an analytical description of the excited guided modes in our structures are presented, showing agreement with experiment. The structures investigated demonstrate a wavelength-flexible, all-semiconductor, plasmonic architecture with potential for both sensing applications and enhanced interaction of midinfrared radiation with integrated semiconductor optoelectronic elements. PMID:24483930

  6. Tunable negative-index photonic crystals using colloidal magnetic fluids

    NASA Astrophysics Data System (ADS)

    Geng, Tao; Wang, Xin; Wang, Yan; Dong, Xiang-Mei

    2015-12-01

    The model of using colloidal magnetic fluid to build tunable negative-index photonic crystal is established. The effective permittivity ɛe and permeability μe of the two-dimensional photonic crystal are investigated in detail. For transverse magnetic polarization, both ɛe and μe exhibit a Lorentz-type anomalous dispersion, leading to a region where ɛe and μe are simultaneously negative. Then, considering a practical case, in which the thickness of photonic crystal is finite, the band structures for odd modes are calculated by the plane wave expansion method and the finite-difference time-domain method. The results suggest that reducing the external magnetic field strength or slab thickness will weaken the periodic modulation strength of the photonic crystal. Simulation results prove that the negative-index can be tuned by varying the external magnetic field strength or the slab thickness. The work presented in this paper gives a guideline for realizing the flat photonic crystal lens with tunable properties at optical frequencies, which may have potential applications in tunable near-field imaging systems. Project supported by the National Basic Research Program of China (Grant No. 2015CB352001), the Shanghai Rising-Star Program, China (Grant No. 12QA1402300), the China Scholarship Council (CSC) Program, and the Basic Research Program of Shanghai, China (Grant No. 14ZR1428500).

  7. Theory of fishnet negative-index optical metamaterials.

    PubMed

    Yang, J; Sauvan, C; Liu, H T; Lalanne, P

    2011-07-22

    We theoretically study fishnet metamaterials at optical frequencies. In contrast with earlier works, we provide a microscopic description by tracking the transversal and longitudinal flows of energy through the fishnet mesh composed of intersecting subwavelength plasmonic waveguides. The analysis is supported by a semianalytical model based on surface-plasmon coupled-mode equations, which provides accurate formulas for the fishnet refractive index, including the real-negative and imaginary parts. The model simply explains how the surface plasmons couple at the waveguide intersections, and it shines new light on the fishnet negative-index paradigm at optical frequencies. Extension of the theory for loss-compensated metamaterials with gain media is also presented.

  8. Intra-connected three-dimensionally isotropic bulk negative index photonic metamaterial

    SciTech Connect

    Guney, Durdu; Koschny, Thomas; Soukoulis, Costas

    2010-05-26

    Isotropic negative index metamaterials (NIMs) are highly desired, particularly for the realization of ultra-high resolution lenses. However, existing isotropic NIMs function only two-dimensionally and cannot be miniaturized beyond microwaves. Direct laser writing processes can be a paradigm shift toward the fabrication of three-dimensionally (3D) isotropic bulk optical metamaterials, but only at the expense of an additional design constraint, namely connectivity. Here, we demonstrate with a proof-of-principle design that the requirement connectivity does not preclude fully isotropic left-handed behavior. This is an important step towards the realization of bulk 3D isotropic NIMs at optical wavelengths.

  9. Negative Index Refraction in the Complex Ginzburg—Landau Equation in Connection with the Experimental CIMA Reaction

    NASA Astrophysics Data System (ADS)

    Yuan, Xu-Jin

    2012-09-01

    In comparison with the phenomenon of negative index refraction observed in artificial meta-materials, it is interesting to ask if this type of behavior also exists or not in reaction-diffusion systems that support nonlinear chemical waves. Previous studies indicate that the negative index refraction could occur on a interface between a medium of a normal wave and a medium that supports anti-waves. Here we investigate the phenomenon in the complex Ginzburg—Landau equation (CGLE) in a close relationship with the quantitative model for the chloriteiodide-malonic acid (CIMA) reaction. The amplitude equation CGLE is deduced from the CIMA reaction, and simulations with mapped parameters from the reaction-diffusion equation reveal that the competition between normal waves and anti-waves on the interface determines whether the negative index refraction occurs or not.

  10. Biological materials by design.

    PubMed

    Qin, Zhao; Dimas, Leon; Adler, David; Bratzel, Graham; Buehler, Markus J

    2014-02-19

    In this topical review we discuss recent advances in the use of physical insight into the way biological materials function, to design novel engineered materials 'from scratch', or from the level of fundamental building blocks upwards and by using computational multiscale methods that link chemistry to material function. We present studies that connect advances in multiscale hierarchical material structuring with material synthesis and testing, review case studies of wood and other biological materials, and illustrate how engineered fiber composites and bulk materials are designed, modeled, and then synthesized and tested experimentally. The integration of experiment and simulation in multiscale design opens new avenues to explore the physics of materials from a fundamental perspective, and using complementary strengths from models and empirical techniques. Recent developments in this field illustrate a new paradigm by which complex material functionality is achieved through hierarchical structuring in spite of simple material constituents. PMID:24451343

  11. Negative index resonant states: a route toward nonmetal plasmonics and metamaterials

    NASA Astrophysics Data System (ADS)

    Mocella, V.; Dardano, P.; De Luca, A. C.; De Tommasi, E.; Rendina, I.; Romano, S.

    2013-05-01

    Photonic crystal metamaterial can exhibit negative index properties and this behaviour is well described by a resonator model. In this work, we present the experimental evidence that a Lorentz resonator correctly reconstruct data obtained with a negative refracting Photonic Crystal (PhC) by using a standard optical technique, such as ellipsometry. In particular we show that, in the frequency range in which the effective refractive index, neff, is equal to -1, the incident light couples efficiently to the guided modes in the top surface layer of the PhC metamaterial. These modes resemble surface plasmon polariton resonances. In add we present measurements by using standard technique of prism coupling evanescent wave. Once again the presence of localized plasmon-like modes at the surface of a silicon two-dimensional photonic crystal slab is demonstrated. Also in this case, in analogy with surface plasmons supported in metals in a photonic crystal metamaterial, the electromagnetic surface waves arise from a negative effective permittivity. These results opens new strategies in light control at the nanoscale, allowing on chip light manipulation in a wide frequency range and avoiding the intrinsic limits of plasmonic structures due to absorption losses in metals. Such negative index PhC materials may be of use in biosensing applications.

  12. Optical waves in a gradient negative-index lens of a half-infinite length.

    PubMed

    Ding, Yi S; Chan, C T; Wang, R P

    2013-01-01

    Materials with negative permittivity and permeability can overcome the diffraction limit, thereby making the sub-wavelength imaging possible. In this study, we analyze the effects of gradient index on a half-infinite perfect lens. We assume that the sharp interface between the vacuum and the negative-index material is replaced by a smooth transition profile such that the index gradually changing from positive to negative. Interestingly, we find that if the graded index profile is modeled by a tanh function, we can have closed-form analytical solutions for this problem, which is a distinct advantage as numerical solutions are not accurate for evanescent waves with large transverse wave vectors. By analyzing the analytical formulas we confirm that a nonzero total absorption can occur even for a near-zero absorption coefficient in the steady-state limit and the image plane contains multiple sub-wavelength images of an object. PMID:24129667

  13. Metallo-dielectric core-shell nanospheres as building blocks for optical three-dimensional isotropic negative-index metamaterials

    NASA Astrophysics Data System (ADS)

    Paniagua-Domínguez, R.; López-Tejeira, F.; Marqués, R.; Sánchez-Gil, J. A.

    2011-12-01

    Materials showing electromagnetic properties that are not attainable in naturally occurring media, so-called metamaterials, have been lately, and still are, among the most active topics in optical and materials physics and engineering. Among these properties, one of the most attractive ones is the sub-diffraction resolving capability predicted for media having an index of refraction of -1. Here, we propose a fully three-dimensional, isotropic metamaterial with strong electric and magnetic responses in the optical regime, based on spherical metallo-dielectric core-shell nanospheres. The magnetic response stems from the lowest, magnetic-dipole resonance of the dielectric shell with a high refractive index, and can be tuned to coincide with the plasmon resonance of the metal core, responsible for the electric response. Since the response does not originate from coupling between structures, no particular periodic arrangement needs to be imposed. Moreover, due to the geometry of the constituents, the metamaterial is intrinsically isotropic and polarization independent. It could be realized with current fabrication techniques with materials such as silver (core) and silicon or germanium (shell). For these particular realistic designs, the metamaterials present a negative index in the range of 1.2-1.55 μm.

  14. Negative index of refraction in a four-level system with magnetoelectric cross coupling and local field corrections

    SciTech Connect

    Bello, F.

    2011-07-15

    This research focuses on a coherently driven four-level atomic medium with the aim of inducing a negative index of refraction while taking into consideration local field corrections as well as magnetoelectric cross coupling (i.e.,chirality) within the material's response functions. Two control fields are used to render the medium transparent for a probe field which simultaneously couples to an electric and a magnetic dipole transition, thus allowing one to test the permittivity and permeability of the material at the same time. Numerical simulations show that a negative index of refraction with low absorption can be obtained for a range of probe detunings while depending on number density and the ratio between the intensities of the control fields.

  15. Design a Sculpting Material

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2011-01-01

    Artists have used a variety of materials over the years for sculpting. They have been quick to use unusual pieces of technology to make a vibrant and unique statement, just as painters have created and used a wide variety of colors and derived pigments for their canvases. In this article, the author discusses a design challenge that gives students…

  16. Ultra low-loss, isotropic optical negative-index metamaterial based on hybrid metal-semiconductor nanowires

    PubMed Central

    Paniagua-Domínguez, R.; Abujetas, D. R.; Sánchez-Gil, J. A.

    2013-01-01

    Recently, many fascinating properties predicted for metamaterials (negative refraction, superlensing, electromagnetic cloaking,…) were experimentally demonstrated. Unfortunately, the best achievements have no direct translation to the optical domain, without being burdened by technological and conceptual difficulties. Of particular importance within the realm of optical negative-index metamaterials (NIM), is the issue of simultaneously achieving strong electric and magnetic responses and low associated losses. Here, hybrid metal-semiconductor nanowires are proposed as building blocks of optical NIMs. The metamaterial thus obtained, highly isotropic in the plane normal to the nanowires, presents a negative index of refraction in the near-infrared, with values of the real part well below −1, and extremely low losses (an order of magnitude better than present optical NIMs). Tunability of the system allows to select the operating range in the whole telecom spectrum. The design is proven in configurations such as prisms and slabs, directly observing negative refraction. PMID:23514968

  17. Soft 3D acoustic metamaterial with negative index.

    PubMed

    Brunet, Thomas; Merlin, Aurore; Mascaro, Benoit; Zimny, Kevin; Leng, Jacques; Poncelet, Olivier; Aristégui, Christophe; Mondain-Monval, Olivier

    2015-04-01

    Many efforts have been devoted to the design and achievement of negative-refractive-index metamaterials since the 2000s. One of the challenges at present is to extend that field beyond electromagnetism by realizing three-dimensional (3D) media with negative acoustic indices. We report a new class of locally resonant ultrasonic metafluids consisting of a concentrated suspension of macroporous microbeads engineered using soft-matter techniques. The propagation of Gaussian pulses within these random distributions of 'ultra-slow' Mie resonators is investigated through in situ ultrasonic experiments. The real part of the acoustic index is shown to be negative (up to almost - 1) over broad frequency bandwidths, depending on the volume fraction of the microbeads as predicted by multiple-scattering calculations. These soft 3D acoustic metamaterials open the way for key applications such as sub-wavelength imaging and transformation acoustics, which require the production of acoustic devices with negative or zero-valued indices. PMID:25502100

  18. Looking for design in materials design.

    PubMed

    Eberhart, M E; Clougherty, D P

    2004-10-01

    Despite great advances in computation, materials design is still science fiction. The construction of structure-property relations on the quantum scale will turn computational empiricism into true design. PMID:15467684

  19. Looking for design in materials design

    NASA Astrophysics Data System (ADS)

    Eberhart, M. E.; Clougherty, D. P.

    2004-10-01

    Despite great advances in computation, materials design is still science fiction. The construction of structure-property relations on the quantum scale will turn computational empiricism into true design.

  20. Co-sputtered SiC + Ag nanomixtures as visible wavelength negative index metamaterials.

    PubMed

    Nehmetallah, G; Aylo, R; Powers, P; Sarangan, A; Gao, J; Li, H; Achari, A; Banerjee, P P

    2012-03-26

    The fabrication and characterization of a novel metamaterial that shows negative index in the visible (blue) is reported. The real part of the negative index of this metamaterial at 405 nm, comprising co-sputtered SiC + Ag nanoparticle mixture on a glass substrate, is deduced from results of double Michelson interferometry setup which shows a negative phase delay. It is numerically verified that this metamaterial can yield near-field super-resolution imaging for both TE and TM polarizations. PMID:22453391

  1. Negative-index gratings formed by femtosecond laser overexposure and thermal regeneration

    PubMed Central

    He, Jun; Wang, Yiping; Liao, Changrui; Wang, Chao; Liu, Shen; Yang, Kaiming; Wang, Ying; Yuan, Xiaocong; Wang, Guo Ping; Zhang, Wenjing

    2016-01-01

    We demonstrate a method for the preparation of negative-index fibre Bragg gratings (FBGs) using 800 nm femtosecond laser overexposure and thermal regeneration. A positive-index type I-IR FBG was first inscribed in H2-free single-mode fibre using a femtosecond laser directed through a phase mask, and then a highly polarization dependant phase-shifted FBG (P-PSFBG) was fabricated from the type I-IR FBG by overexposure to the femtosecond laser. Subsequently, the P-PSFBG was thermally annealed at 800 °C for 12 hours. Grating regeneration was observed during thermal annealing, and a negative-index FBG was finally obtained with a high reflectivity of 99.22%, an ultra-low insertion loss of 0.08 dB, a blueshift of 0.83 nm in the Bragg wavelength, and an operating temperature of up to 1000 °C for more than 10 hours. Further annealing tests showed that the thermal stability of the negative-index FBG was lower than that of a type II-IR FBG, but much higher than that of a type I-IR FBG. Moreover, the formation of such a negative-index grating may result from thermally regenerated type IIA photosensitivity. PMID:26979090

  2. Negative-index gratings formed by femtosecond laser overexposure and thermal regeneration

    NASA Astrophysics Data System (ADS)

    He, Jun; Wang, Yiping; Liao, Changrui; Wang, Chao; Liu, Shen; Yang, Kaiming; Wang, Ying; Yuan, Xiaocong; Wang, Guo Ping; Zhang, Wenjing

    2016-03-01

    We demonstrate a method for the preparation of negative-index fibre Bragg gratings (FBGs) using 800 nm femtosecond laser overexposure and thermal regeneration. A positive-index type I-IR FBG was first inscribed in H2-free single-mode fibre using a femtosecond laser directed through a phase mask, and then a highly polarization dependant phase-shifted FBG (P-PSFBG) was fabricated from the type I-IR FBG by overexposure to the femtosecond laser. Subsequently, the P-PSFBG was thermally annealed at 800 °C for 12 hours. Grating regeneration was observed during thermal annealing, and a negative-index FBG was finally obtained with a high reflectivity of 99.22%, an ultra-low insertion loss of 0.08 dB, a blueshift of 0.83 nm in the Bragg wavelength, and an operating temperature of up to 1000 °C for more than 10 hours. Further annealing tests showed that the thermal stability of the negative-index FBG was lower than that of a type II-IR FBG, but much higher than that of a type I-IR FBG. Moreover, the formation of such a negative-index grating may result from thermally regenerated type IIA photosensitivity.

  3. Materials design for new superconductors

    NASA Astrophysics Data System (ADS)

    Norman, M. R.

    2016-07-01

    Since the announcement in 2011 of the Materials Genome Initiative by the Obama administration, much attention has been given to the subject of materials design to accelerate the discovery of new materials that could have technological implications. Although having its biggest impact for more applied materials like batteries, there is increasing interest in applying these ideas to predict new superconductors. This is obviously a challenge, given that superconductivity is a many body phenomenon, with whole classes of known superconductors lacking a quantitative theory. Given this caveat, various efforts to formulate materials design principles for superconductors are reviewed here, with a focus on surveying the periodic table in an attempt to identify cuprate analogues.

  4. Specific absorption rate analysis of broadband mobile antenna with negative index metamaterial

    NASA Astrophysics Data System (ADS)

    Alam, Touhidul; Faruque, Mohammad Rashed Iqbal; Islam, Mohammad Tariqul

    2016-03-01

    This paper presents a negative index metamaterial-inspired printed mobile wireless antenna that can support most mobile applications such as GSM, UMTS, Bluetooth and WLAN frequency bands. The antenna consists of a semi-circular patch, a 50Ω microstrip feed line and metamaterial ground plane. The antenna occupies a very small space of 37 × 47 × 0.508 mm3, making it suitable for mobile wireless application. The perceptible novelty shown in this proposed antenna is that reduction of specific absorption rate using the negative index metamaterial ground plane. The proposed antenna reduced 72.11 and 75.53 % of specific absorption rate at 1.8 and 2.4 GHz, respectively.

  5. Materials design for new superconductors.

    PubMed

    Norman, M R

    2016-07-01

    Since the announcement in 2011 of the Materials Genome Initiative by the Obama administration, much attention has been given to the subject of materials design to accelerate the discovery of new materials that could have technological implications. Although having its biggest impact for more applied materials like batteries, there is increasing interest in applying these ideas to predict new superconductors. This is obviously a challenge, given that superconductivity is a many body phenomenon, with whole classes of known superconductors lacking a quantitative theory. Given this caveat, various efforts to formulate materials design principles for superconductors are reviewed here, with a focus on surveying the periodic table in an attempt to identify cuprate analogues. PMID:27214291

  6. Advanced Aerospace Materials by Design

    NASA Technical Reports Server (NTRS)

    Srivastava, Deepak; Djomehri, Jahed; Wei, Chen-Yu

    2004-01-01

    The advances in the emerging field of nanophase thermal and structural composite materials; materials with embedded sensors and actuators for morphing structures; light-weight composite materials for energy and power storage; and large surface area materials for in-situ resource generation and waste recycling, are expected to :revolutionize the capabilities of virtually every system comprising of future robotic and :human moon and mars exploration missions. A high-performance multiscale simulation platform, including the computational capabilities and resources of Columbia - the new supercomputer, is being developed to discover, validate, and prototype next generation (of such advanced materials. This exhibit will describe the porting and scaling of multiscale 'physics based core computer simulation codes for discovering and designing carbon nanotube-polymer composite materials for light-weight load bearing structural and 'thermal protection applications.

  7. A Negative Index Metamaterial-Inspired UWB Antenna with an Integration of Complementary SRR and CLS Unit Cells for Microwave Imaging Sensor Applications

    PubMed Central

    Islam, Mohammad Tariqul; Islam, Md. Moinul; Samsuzzaman, Md.; Faruque, Mohammad Rashed Iqbal; Misran, Norbahiah

    2015-01-01

    This paper presents a negative index metamaterial incorporated UWB antenna with an integration of complementary SRR (split-ring resonator) and CLS (capacitive loaded strip) unit cells for microwave imaging sensor applications. This metamaterial UWB antenna sensor consists of four unit cells along one axis, where each unit cell incorporates a complementary SRR and CLS pair. This integration enables a design layout that allows both a negative value of permittivity and a negative value of permeability simultaneous, resulting in a durable negative index to enhance the antenna sensor performance for microwave imaging sensor applications. The proposed MTM antenna sensor was designed and fabricated on an FR4 substrate having a thickness of 1.6 mm and a dielectric constant of 4.6. The electrical dimensions of this antenna sensor are 0.20 λ × 0.29 λ at a lower frequency of 3.1 GHz. This antenna sensor achieves a 131.5% bandwidth (VSWR < 2) covering the frequency bands from 3.1 GHz to more than 15 GHz with a maximum gain of 6.57 dBi. High fidelity factor and gain, smooth surface-current distribution and nearly omni-directional radiation patterns with low cross-polarization confirm that the proposed negative index UWB antenna is a promising entrant in the field of microwave imaging sensors. PMID:26007721

  8. A Negative Index Metamaterial-Inspired UWB Antenna with an Integration of Complementary SRR and CLS Unit Cells for Microwave Imaging Sensor Applications.

    PubMed

    Islam, Mohammad Tariqul; Islam, Md Moinul; Samsuzzaman, Md; Faruque, Mohammad Rashed Iqbal; Misran, Norbahiah

    2015-05-20

    This paper presents a negative index metamaterial incorporated UWB antenna with an integration of complementary SRR (split-ring resonator) and CLS (capacitive loaded strip) unit cells for microwave imaging sensor applications. This metamaterial UWB antenna sensor consists of four unit cells along one axis, where each unit cell incorporates a complementary SRR and CLS pair. This integration enables a design layout that allows both a negative value of permittivity and a negative value of permeability simultaneous, resulting in a durable negative index to enhance the antenna sensor performance for microwave imaging sensor applications. The proposed MTM antenna sensor was designed and fabricated on an FR4 substrate having a thickness of 1.6 mm and a dielectric constant of 4.6. The electrical dimensions of this antenna sensor are 0.20 λ × 0.29 λ at a lower frequency of 3.1 GHz. This antenna sensor achieves a 131.5% bandwidth (VSWR < 2) covering the frequency bands from 3.1 GHz to more than 15 GHz with a maximum gain of 6.57 dBi. High fidelity factor and gain, smooth surface-current distribution and nearly omni-directional radiation patterns with low cross-polarization confirm that the proposed negative index UWB antenna is a promising entrant in the field of microwave imaging sensors.

  9. Triangular lattice of carbon nanotube arrays for negative index of refraction and subwavelength lensing effect

    SciTech Connect

    Wang, Y.; Wang, X.; Rybczynski, J.; Wang, D.Z.; Kempa, K.; Ren, Z.F.

    2005-04-11

    Self-assembly of polystyrene microspheres has been utilized in a two-step masking technique to prepare triangular lattices of catalytic nanodots at low cost. Subsequent triangular lattices of aligned carbon nanotubes on a silicon substrate are achieved by plasma-enhanced chemical vapor deposition. Nickel is used both in the nanodots and in the secondary mask. The triangular lattices of carbon nanotube arrays as two-dimensional photonic crystals show higher geometrical symmetry than the hexagonal lattices previously reported, enabling broader applications including negative index of refraction and subwavelength lensing effect.

  10. Principles of Inorganic Materials Design

    NASA Astrophysics Data System (ADS)

    Lalena, John N.; Cleary, David

    2005-04-01

    A unique interdisciplinary approach to inorganic materials design Textbooks intended for the training of chemists in the inorganic materials field often omit many relevant topics. With its interdisciplinary approach, this book fills that gap by presenting concepts from chemistry, physics, materials science, metallurgy, and ceramics in a unified treatment targeted towards the chemistry audience. Semiconductors, metal alloys and intermetallics, as well as ceramic substances are covered. Accordingly, the book should also be useful to students and working professionals in a variety of other disciplines. This book discusses a number of topics that are pertinent to the design of new inorganic materials but are typically not covered in standard solid-state chemistry books. The authors start with an introduction to structure at the mesoscopic level and progress to smaller-length scales. Next, detailed consideration is given to both phenomenological and atomistic-level descriptions of transport properties, the metal-nonmetal transition, magnetic and dielectric properties, optical properties, and mechanical properties. Finally, the authors present introductions to phase equilibria, synthesis, and nanomaterials. Other features include: Worked examples demonstrating concepts unfamiliar to the chemist Extensive references to related literature, leading readers to more in-depth coverage of particular topics Biographies introducing the reader to great contributors to the field of inorganic materials science in the twentieth century With their interdisciplinary approach, the authors have set the groundwork for communication and understanding among professionals in varied disciplines who are involved with inorganic materials engineering. Armed with this publication, students and researchers in inorganic and physical chemistry, physics, materials science, and engineering will be better equipped to face today's complex design challenges. This textbook is appropriate for senior

  11. Spatial mapping of the internal and external electromagnetic fields of negative index metamaterials.

    PubMed

    Justice, Bryan J; Mock, Jack J; Guo, Liheng; Degiron, Aloyse; Schurig, David; Smith, David R

    2006-09-18

    We perform an experimental study of the phase and amplitude of microwaves interacting with and scattered by two-dimensional negative index metamaterials. The measurements are performed in a parallel plate waveguide apparatus at X-band frequencies (8-12 GHz), thus constraining the electromagnetic fields to two dimensions. A detection antenna is fixed to one of the plates, while a second plate with a fixed source antenna or waveguide is translated relative to the first plate. The detection antenna is inserted into, but not protruding below, the stationary plate so that fields internal to the metamaterial samples can be mapped. From the measured mappings of the electric field, the interplay between the microstructure of the metamaterial lattice and the macroscopic averaged response is revealed. For example, the mapped phase fronts within a metamaterial having a negative refractive index are consistent with a macroscopic phase-in accordance with the effective medium predictions-which travels in a direction opposite to the direction of propagation. The field maps are in excellent agreement with finite element numerical simulations performed assuming homogeneous metamaterial structures. PMID:19529250

  12. Designer Nanocrystal Materials for Photovoltaics

    NASA Astrophysics Data System (ADS)

    Kagan, Cherie

    Advances in synthetic methods allow a wide range of semiconductor nanocrystals (NCs) to be tailored in size and shape and to be used as building blocks in the design of NC solids. However, the long, insulating ligands commonly employed in the synthesis of colloidal NCs inhibit strong interparticle coupling and charge transport once NCs are assembled into the solids state as NC arrays. We will describe the range of short, compact ligand chemistries we employ to exchange the long, insulating ligands used in synthesis and to increase interparticle coupling. These ligand exchange processes can have a dramatic influence on NC surface chemistry as well as NC organization in the solids, showing examples of short-range order. Synergistically, we use 1) thermal evaporation and diffusion and 2) wet-chemical methods to introduce extrinsic impurities and non-stoichiometry to passivate surface traps and dope NC solids. NC coupling and doping provide control over the density of states and the carrier type, concentration, mobility, and lifetime, which we characterize by a range of electronic and spectroscopic techniques. We will describe the importance of engineering device interfaces to design NC materials for solar photovoltaics.

  13. Shear-mediated contributions to the effective properties of soft acoustic metamaterials including negative index.

    PubMed

    Forrester, Derek Michael; Pinfield, Valerie J

    2015-01-01

    Here we show that, for sub-wavelength particles in a fluid, viscous losses due to shear waves and their influence on neighbouring particles significantly modify the effective acoustic properties, and thereby the conditions at which negative acoustic refraction occurs. Building upon earlier single particle scattering work, we adopt a multiple scattering approach to derive the effective properties (density, bulk modulus, wavenumber). We show,through theoretical prediction, the implications for the design of "soft" (ultrasonic) metamaterials based on locally-resonant sub-wavelength porous rubber particles, through selection of particle size and concentration, and demonstrate tunability of the negative speed zones by modifying the viscosity of the suspending medium. For these lossy materials with complex effective properties, we confirm the use of phase angles to define the backward propagation condition in preference to "single-" and "double-negative" designations. PMID:26686414

  14. Shear-mediated contributions to the effective properties of soft acoustic metamaterials including negative index

    PubMed Central

    Forrester, Derek Michael; Pinfield, Valerie J.

    2015-01-01

    Here we show that, for sub-wavelength particles in a fluid, viscous losses due to shear waves and their influence on neighbouring particles significantly modify the effective acoustic properties, and thereby the conditions at which negative acoustic refraction occurs. Building upon earlier single particle scattering work, we adopt a multiple scattering approach to derive the effective properties (density, bulk modulus, wavenumber). We show,through theoretical prediction, the implications for the design of “soft” (ultrasonic) metamaterials based on locally-resonant sub-wavelength porous rubber particles, through selection of particle size and concentration, and demonstrate tunability of the negative speed zones by modifying the viscosity of the suspending medium. For these lossy materials with complex effective properties, we confirm the use of phase angles to define the backward propagation condition in preference to “single-” and “double-negative” designations. PMID:26686414

  15. Materials informatics: a journey towards material design and synthesis.

    PubMed

    Takahashi, Keisuke; Tanaka, Yuzuru

    2016-06-28

    Materials informatics has been gaining popularity with the rapid development of computational materials science. However, collaborations between information science and materials science have not yet reached the success. There are several issues which need to be overcome in order to establish the field of materials informatics. Construction of material big data, implementation of machine learning, and platform design for materials discovery are discussed with potential solutions. PMID:27292550

  16. Materials informatics: a journey towards material design and synthesis.

    PubMed

    Takahashi, Keisuke; Tanaka, Yuzuru

    2016-06-28

    Materials informatics has been gaining popularity with the rapid development of computational materials science. However, collaborations between information science and materials science have not yet reached the success. There are several issues which need to be overcome in order to establish the field of materials informatics. Construction of material big data, implementation of machine learning, and platform design for materials discovery are discussed with potential solutions.

  17. ALTERNATE MATERIALS IN DESIGN OF RADIOACTIVE MATERIAL PACKAGES

    SciTech Connect

    Blanton, P.; Eberl, K.

    2010-07-09

    This paper presents a summary of design and testing of material and composites for use in radioactive material packages. These materials provide thermal protection and provide structural integrity and energy absorption to the package during normal and hypothetical accident condition events as required by Title 10 Part 71 of the Code of Federal Regulations. Testing of packages comprising these materials is summarized.

  18. Managing Training Materials with Structured Text Design.

    ERIC Educational Resources Information Center

    Streit, Les D.; And Others

    1986-01-01

    Describes characteristics of structured text design; benefits of its use in training; benefits for developers of training materials and steps in preparing training materials. A case study illustrating how the structured text design process solved the sales training needs of the Mercedes-Benz Truck Company is presented. (MBR)

  19. OLED microdisplay design and materials

    NASA Astrophysics Data System (ADS)

    Wacyk, Ihor; Prache, Olivier; Ali, Tariq; Khayrullin, Ilyas; Ghosh, Amalkumar

    2010-04-01

    AMOLED microdisplays from eMagin Corporation are finding growing acceptance within the military display market as a result of their excellent power efficiency, wide operating temperature range, small size and weight, good system flexibility, and ease of use. The latest designs have also demonstrated improved optical performance including better uniformity, contrast, MTF, and color gamut. eMagin's largest format display is currently the SXGA design, which includes features such as a 30-bit wide RGB digital interface, automatic luminance regulation from -45 to +70°C, variable gamma control, and a dynamic range exceeding 50:000 to 1. This paper will highlight the benefits of eMagin's latest microdisplay designs and review the roadmap for next generation devices. The ongoing development of reduced size pixels and larger format displays (up to WUXGA) as well as new OLED device architecture (e.g. high-brightness yellow) will be discussed. Approaches being explored for improved performance in next generation designs such as lowpower serial interfaces, high frame rate operation, and new operational modes for reduction of motion artifacts will also be described. These developments should continue to enhance the appeal of AMOLED microdisplays for a broad spectrum of near-to-the-eye applications such as night vision, simulation and training, situational awareness, augmented reality, medical imaging, and mobile video entertainment and gaming.

  20. Topology Optimization for Architected Materials Design

    NASA Astrophysics Data System (ADS)

    Osanov, Mikhail; Guest, James K.

    2016-07-01

    Advanced manufacturing processes provide a tremendous opportunity to fabricate materials with precisely defined architectures. To fully leverage these capabilities, however, materials architectures must be optimally designed according to the target application, base material used, and specifics of the fabrication process. Computational topology optimization offers a systematic, mathematically driven framework for navigating this new design challenge. The design problem is posed and solved formally as an optimization problem with unit cell and upscaling mechanics embedded within this formulation. This article briefly reviews the key requirements to apply topology optimization to materials architecture design and discusses several fundamental findings related to optimization of elastic, thermal, and fluidic properties in periodic materials. Emerging areas related to topology optimization for manufacturability and manufacturing variations, nonlinear mechanics, and multiscale design are also discussed.

  1. Design and Manufacture of Energy Absorbing Materials

    ScienceCinema

    Duoss, Eric

    2016-07-12

    Learn about an ordered cellular material that has been designed and manufactured using direct ink writing (DIW), a 3-D printing technology being developed at LLNL. The new material is a patterned cellular material that can absorb mechanical energy-a cushion-while also providing protection against sheering. This material is expected to find utility in application spaces that currently use unordered foams, such as sporting and consumer goods as well as defense and aerospace.

  2. Design and Manufacture of Energy Absorbing Materials

    SciTech Connect

    Duoss, Eric

    2014-05-28

    Learn about an ordered cellular material that has been designed and manufactured using direct ink writing (DIW), a 3-D printing technology being developed at LLNL. The new material is a patterned cellular material that can absorb mechanical energy-a cushion-while also providing protection against sheering. This material is expected to find utility in application spaces that currently use unordered foams, such as sporting and consumer goods as well as defense and aerospace.

  3. Integrated design of structures, controls, and materials

    NASA Technical Reports Server (NTRS)

    Blankenship, G. L.

    1994-01-01

    In this talk we shall discuss algorithms and CAD tools for the design and analysis of structures for high performance applications using advanced composite materials. An extensive mathematical theory for optimal structural (e.g., shape) design was developed over the past thirty years. Aspects of this theory have been used in the design of components for hypersonic vehicles and thermal diffusion systems based on homogeneous materials. Enhancement of the design methods to include optimization of the microstructure of the component is a significant innovation which can lead to major enhancements in component performance. Our work is focused on the adaptation of existing theories of optimal structural design (e.g., optimal shape design) to treat the design of structures using advanced composite materials (e.g., fiber reinforced, resin matrix materials). In this talk we shall discuss models and algorithms for the design of simple structures from composite materials, focussing on a problem in thermal management. We shall also discuss methods for the integration of active structural controls into the design process.

  4. Materials design and development of functional materials for industry.

    PubMed

    Asahi, Ryoji; Morikawa, Takeshi; Hazama, Hirofumi; Matsubara, Masato

    2008-02-13

    It is now well recognized that we are witnessing a golden age of innovation with novel materials, with discoveries that are important for both basic science and industry. With the development of theory along with computing power, quantum materials design-the synthesis of materials with the desired properties in a controlled way via materials engineering on the atomic scale-is becoming a major component of materials research. Computational prediction based on first-principles calculations has helped to find an efficient way to develop materials that are much needed for industry, as we have seen in the successful development of visible-light sensitized photocatalysts and thermoelectric materials. Close collaboration between theory and experiment is emphasized as an essential for success.

  5. Computationally Designed Molecularly Imprinted Materials

    NASA Astrophysics Data System (ADS)

    Pavel, Dumitru; Lagowski, Jolanta; Faid, Karim

    2004-03-01

    Molecular dynamics simulations were carried out for different molecular systems in order to predict the binding affinities, binding energies, binding distances and the active site groups between the simulated molecular systems and different bio-ligands (theophylline and its derivatives), which have been designed and minimized using molecular simulation techniques. The first simulated molecular systems consisted of a ligand and functional monomer, such as methacrylic acid and its derivatives. For each pair of molecular systems, (10 monomers with a ligand and 10 monomers without a ligand) a total energy difference was calculated in order to estimate the binding energy between a ligand and the corresponding monomers. The analysis of the simulated functional monomers with ligands indicates that the functional group of monomers interacting with ligands tends to be either COOH or CH2=CH. The distances between the ligand and monomer, in the most stable cases as indicated above, are between 2.0-4.5 Å. The second simulated molecular systems consisted of a ligand and a polymer. The polymers were obtained from monomers that were simulated above. And similar to monomer study, for each pair of molecular systems, (polymer with a ligand and polymer without a ligand) a total energy difference was calculated in order to estimate the binding energy between ligand and the corresponding polymer. The binding distance between the active site of a polymer and a ligand will also be discussed.

  6. Design principles for therapeutic angiogenic materials

    NASA Astrophysics Data System (ADS)

    Briquez, Priscilla S.; Clegg, Lindsay E.; Martino, Mikaël M.; Gabhann, Feilim Mac; Hubbell, Jeffrey A.

    2016-01-01

    Despite extensive research, pro-angiogenic drugs have failed to translate clinically, and therapeutic angiogenesis, which has potential in the treatment of various cardiovascular diseases, remains a major challenge. Physiologically, angiogenesis — the process of blood-vessel growth from existing vasculature — is regulated by a complex interplay of biophysical and biochemical cues from the extracellular matrix (ECM), angiogenic factors and multiple cell types. The ECM can be regarded as the natural 3D material that regulates angiogenesis. Here, we leverage knowledge of ECM properties to derive design rules for engineering pro-angiogenic materials. We propose that pro-angiogenic materials should be biomimetic, incorporate angiogenic factors and mimic cooperative interactions between growth factors and the ECM. We highlight examples of material designs that demonstrate these principles and considerations for designing better angiogenic materials.

  7. Adaptive Strategies for Materials Design using Uncertainties.

    PubMed

    Balachandran, Prasanna V; Xue, Dezhen; Theiler, James; Hogden, John; Lookman, Turab

    2016-01-21

    We compare several adaptive design strategies using a data set of 223 M2AX family of compounds for which the elastic properties [bulk (B), shear (G), and Young's (E) modulus] have been computed using density functional theory. The design strategies are decomposed into an iterative loop with two main steps: machine learning is used to train a regressor that predicts elastic properties in terms of elementary orbital radii of the individual components of the materials; and a selector uses these predictions and their uncertainties to choose the next material to investigate. The ultimate goal is to obtain a material with desired elastic properties in as few iterations as possible. We examine how the choice of data set size, regressor and selector impact the design. We find that selectors that use information about the prediction uncertainty outperform those that don't. Our work is a step in illustrating how adaptive design tools can guide the search for new materials with desired properties.

  8. Role of phase matching in pulsed second-harmonic generation: Walk-off and phase-locked twin pulses in negative-index media

    SciTech Connect

    Roppo, Vito; Centini, Marco; Sibilia, Concita; Bertolotti, Mario; De Ceglia, Domenico; Scalora, Michael; Akozbek, Neset; Bloemer, Mark J.; Haus, Joseph W.; Kosareva, Olga G.; Kandidov, Valery P.

    2007-09-15

    The present investigation is concerned with the study of pulsed second-harmonic generation under conditions of phase and group velocity mismatch, and generally low conversion efficiencies and pump intensities. In positive-index, nonmetallic materials, we generally find qualitative agreement with previous reports regarding the presence of a double-peaked second harmonic signal, which comprises a pulse that walks off and propagates at the nominal group velocity one expects at the second-harmonic frequency, and a second pulse that is 'captured' and propagates under the pump pulse. We find that the origin of the double-peaked structure resides in a phase-locking mechanism that characterizes not only second-harmonic generation, but also {chi}{sup (3)} processes and third-harmonic generation. The phase-locking mechanism that we describe occurs for arbitrarily small pump intensities, and so it is not a soliton effect, which usually relies on a threshold mechanism, although multicolor solitons display similar phase locking characteristics. Thus, in second harmonic generation a phase-matched component is always generated, even under conditions of material phase mismatch: This component is anomalous, because the material does not allow energy exchange between the pump and the second-harmonic beam. On the other hand, if the material is phase matched, phase locking and phase matching are indistinguishable, and the conversion process becomes efficient. We also report a similar phase-locking phenomenon in negative index materials. A spectral analysis of the pump and the generated signals reveals that the phase-locking phenomenon causes the forward moving, phase-locked second-harmonic pulse to experience the same negative index as the pump pulse, even though the index of refraction at the second-harmonic frequency is positive. Our analysis further shows that the reflected second-harmonic pulse generated at the interface and the forward-moving, phase-locked pulse appear to be part

  9. Design and Evaluation Issues on CAL Materials.

    ERIC Educational Resources Information Center

    England, Elaine

    1984-01-01

    Suggests that insights from other disciplines be considered when evaluating computer-assisted language instruction materials. Issues which need to be considered when evaluating these materials include: design issues, user-machine interfacing, support documentation, screen layout, color and animation, and restricted visual display capacity. (SED)

  10. Functionally graded materials: Design, processing and applications

    SciTech Connect

    Miyamoto, Y.; Kaysser, W.A.; Rabin, B.H.; Kawasaki, A.; Ford, R.G.

    1999-09-01

    In a Functionally Graded Material (FGM), the composition and structure gradually change over volume, resulting in corresponding changes in the properties of the material. By applying the many possibilities inherent in the FGM concept, it is anticipated that materials will be improved and new functions for them created. A comprehensive description of design, modeling, processing, and evaluation of FGMs as well as their applications is covered in this book. The contents include: lessons from nature; graded microstructures; modeling and design; characterization of properties; processing and fabrication; applications; and summary and outlook.

  11. Plasmon Injection to Compensate and Control Losses in Negative Index Metamaterials.

    PubMed

    Sadatgol, Mehdi; Özdemir, Şahin K; Yang, Lan; Güney, Durdu Ö

    2015-07-17

    Metamaterials have introduced a whole new world of unusual materials with functionalities that cannot be attained in naturally occurring material systems by mimicking and controlling the natural phenomena at subwavelength scales. However, the inherent absorption losses pose a fundamental challenge to the most fascinating applications of metamaterials. Based on a novel plasmon injection (PI or Π) scheme, we propose a coherent optical amplification technique to compensate losses in metamaterials. Although the proof of concept device here operates under normal incidence only, our proposed scheme can be generalized to an arbitrary form of incident waves. The Π scheme is fundamentally different from major optical amplification schemes. It does not require a gain medium, interaction with phonons, or any nonlinear medium. The Π scheme allows for loss-free metamaterials. It is ideally suited for mitigating losses in metamaterials operating in the visible spectrum and is scalable to other optical frequencies. These findings open the possibility of reviving the early dreams of making "magical" metamaterials from scratch.

  12. Plasmon Injection to Compensate and Control Losses in Negative Index Metamaterials.

    PubMed

    Sadatgol, Mehdi; Özdemir, Şahin K; Yang, Lan; Güney, Durdu Ö

    2015-07-17

    Metamaterials have introduced a whole new world of unusual materials with functionalities that cannot be attained in naturally occurring material systems by mimicking and controlling the natural phenomena at subwavelength scales. However, the inherent absorption losses pose a fundamental challenge to the most fascinating applications of metamaterials. Based on a novel plasmon injection (PI or Π) scheme, we propose a coherent optical amplification technique to compensate losses in metamaterials. Although the proof of concept device here operates under normal incidence only, our proposed scheme can be generalized to an arbitrary form of incident waves. The Π scheme is fundamentally different from major optical amplification schemes. It does not require a gain medium, interaction with phonons, or any nonlinear medium. The Π scheme allows for loss-free metamaterials. It is ideally suited for mitigating losses in metamaterials operating in the visible spectrum and is scalable to other optical frequencies. These findings open the possibility of reviving the early dreams of making "magical" metamaterials from scratch. PMID:26230802

  13. Plasmon Injection to Compensate and Control Losses in Negative Index Metamaterials

    NASA Astrophysics Data System (ADS)

    Sadatgol, Mehdi; Ã-zdemir, Şahin K.; Yang, Lan; Güney, Durdu Ã.-.

    2015-07-01

    Metamaterials have introduced a whole new world of unusual materials with functionalities that cannot be attained in naturally occurring material systems by mimicking and controlling the natural phenomena at subwavelength scales. However, the inherent absorption losses pose a fundamental challenge to the most fascinating applications of metamaterials. Based on a novel plasmon injection (PI or Π ) scheme, we propose a coherent optical amplification technique to compensate losses in metamaterials. Although the proof of concept device here operates under normal incidence only, our proposed scheme can be generalized to an arbitrary form of incident waves. The Π scheme is fundamentally different from major optical amplification schemes. It does not require a gain medium, interaction with phonons, or any nonlinear medium. The Π scheme allows for loss-free metamaterials. It is ideally suited for mitigating losses in metamaterials operating in the visible spectrum and is scalable to other optical frequencies. These findings open the possibility of reviving the early dreams of making "magical" metamaterials from scratch.

  14. Molecular understanding and design of zwitterionic materials.

    PubMed

    Shao, Qing; Jiang, Shaoyi

    2015-01-01

    Zwitterionic materials have moieties possessing cationic and anionic groups. This molecular structure leads to unique properties that can be the solutions of various application problems. A typical example is that zwitterionic carboxybetaine (CB) and sulfobetaine (SB) materials resist nonspecific protein adsorption in complex media. Considering the vast number of cationic and anionic groups in the current chemical inventory, there are many possible structural variations of zwitterionic materials. The diversified structures provide the possibility to achieve many desired properties and urge a better understanding of zwitterionic materials to provide design principles. Molecular simulations and modeling are a versatile tool to understand the structure-property relationships of materials at the molecular level. This progress report summarizes recent simulation and modeling studies addressing two fundamental questions regarding zwitterionic materials and their applications as biomaterials. First, what are the differences between zwitterionic and nonionic materials? Second, what are the differences among zwitterionic materials? This report also demonstrates a molecular design of new protein-resistant zwitterionic moieties beyond conventional CB and SB based on design principles developed from these simulation studies.

  15. Mimicry of natural material designs and processes

    SciTech Connect

    Bond, G.M.; Richman, R.H.; McNaughton, W.P.

    1995-06-01

    Biological structural materials, although composed of unremarkable substances synthesized at low temperatures, often exhibit superior mechanical properties. In particular, the quality in which nearly all biologically derived materials excel is toughness. The advantageous mechanical properties are attributable to the hierarchical, composite, structural arrangements common to biological systems. Materials scientists and engineers have increasingly recognized that biological designs or processing approaches applied to man-made materials (biomimesis) may offer improvements in performance over conventional designs and fabrication methods. In this survey, the structures and processing routes of marine shells, avian eggshells, wood, bone, and insect cuticle are briefly reviewed, and biomimesis research inspired by these materials is discussed. In addition, this paper describes and summarizes the applications of biomineralization, self-assembly, and templating with proteins to the fabrication of thin ceramic films and nanostructure devices.

  16. Method of designing layered sound absorbing materials

    NASA Astrophysics Data System (ADS)

    Atalla, Youssef; Panneton, Raymond

    2002-11-01

    A widely used model for describing sound propagation in porous materials is the Johnson-Champoux-Allard model. This rigid frame model is based on five geometrical properties of the porous medium: resistivity, porosity, tortuosity, and viscous and thermal characteristic lengths. Using this model and with the knowledge of such properties for different absorbing materials, the design of a multiple layered system can be optimized efficiently and rapidly. The overall impedance of the layered systems can be calculated by the repeated application of single layer impedance equation. The knowledge of the properties of the materials involved in the layered system and their physical meaning, allows to perform by computer a systematic evaluation of potential layer combinations rather than do it experimentally which is time consuming and always not efficient. The final design of layered materials can then be confirmed by suitable measurements. A method of designing the overall acoustic absorption of multiple layered porous materials is presented. Some aspects based on the material properties, for designing a flat layered absorbing system are considered. Good agreement between measured and computed sound absorption coefficients has been obtained for the studied configurations. [Work supported by N.S.E.R.C. Canada, F.C.A.R. Quebec, and Bombardier Aerospace.

  17. Computational design of fused heterocyclic energetic materials

    NASA Astrophysics Data System (ADS)

    Tsyshevskiy, Roman; Pagoria, Philip; Batyrev, Iskander; Kuklja, Maija

    A continuous traditional search for effective energetic materials is often based on a trial and error approach. Understanding of fundamental correlations between the structure and sensitivity of the materials remains the main challenge for design of novel energetics due to the complexity of the behavior of energetic materials. State of the art methods of computational chemistry and solid state physics open new compelling opportunities in simulating and predicting a response of the energetic material to various external stimuli. Hence, theoretical and computational studies can be effectively used not only for an interpretation of sensitivity mechanisms of widely used explosives, but also for identifying criteria for material design prior to its synthesis and experimental characterization. We report here, how knowledge on thermal stability of recently synthesized materials of LLM series is used for design of novel fused heterocyclic energetic materials, including DNBTT (2,7-dinitro-4H,9H-bis([1, 2, 4"]triazolo)[1,5-b:1',5'-e][1, 2, 4, 5]tetrazine), compound with high thermal stability, which is on par or better than that of TATB. This research is supported by ONR (Grant N00014-12-1-0529), NSF XSEDE resources (Grant DMR-130077) and DOE NERSC resources (Contract DE-AC02-05CH11231).

  18. Biomimetic materials design for cardiac tissue regeneration.

    PubMed

    Dunn, David A; Hodge, Alexander J; Lipke, Elizabeth A

    2014-01-01

    Cardiovascular disease is the leading cause of death worldwide. In the absence of sufficient numbers of organs for heart transplant, alternate approaches for healing or replacing diseased heart tissue are under investigation. Designing biomimetic materials to support these approaches will be essential to their overall success. Strategies for cardiac tissue engineering include injection of cells, implantation of three-dimensional tissue constructs or patches, injection of acellular materials, and replacement of valves. To replicate physiological function and facilitate engraftment into native tissue, materials used in these approaches should have properties that mimic those of the natural cardiac environment. Multiple aspects of the cardiac microenvironment have been emulated using biomimetic materials including delivery of bioactive factors, presentation of cell-specific adhesion sites, design of surface topography to guide tissue alignment and dictate cell shape, modulation of mechanical stiffness and electrical conductivity, and fabrication of three-dimensional structures to guide tissue formation and function. Biomaterials can be engineered to assist in stem cell expansion and differentiation, to protect cells during injection and facilitate their retention and survival in vivo, and to provide mechanical support and guidance for engineered tissue formation. Numerous studies have investigated the use of biomimetic materials for cardiac regeneration. Biomimetic material design will continue to exploit advances in nanotechnology to better recreate the cellular environment and advance cardiac regeneration. Overall, biomimetic materials are moving the field of cardiac regenerative medicine forward and promise to deliver new therapies in combating heart disease.

  19. Designing Biomimetic Materials from Marine Organisms.

    PubMed

    Nichols, William T

    2015-01-01

    Two biomimetic design approaches that apply biological solutions to engineering problems are discussed. In the first case, motivation comes from an engineering problem and the key challenge is to find analogous biological functions and map them into engineering materials. We illustrate with an example of water pollution remediation through appropriate design of a biomimetic sponge. In the second case, a biological function is already known and the challenge is to identify the appropriate engineering problem. We demonstrate the biological approach with marine diatoms that control energy and materials at their surface providing inspiration for a number of engineering applications. In both cases, it is essential to select materials and structures at the nanoscale to control energy and materials flows at interfaces.

  20. Survey of intraocular lens material and design.

    PubMed

    Doan, Kim T; Olson, Randall J; Mamalis, Nick

    2002-02-01

    Modern cataract surgery is constantly evolving and improving in terms of lens material and design. Researchers and physicians strive to obtain better refractive correction with smaller wound size and minimizing host cell response to limit the proliferation of lens epithelial cells leading to opacification of the lens capsule. Intraocular lens material varies in water content, refractive index, and tensile strength. Intraocular lens design has undergone revisions to prohibit lens epithelial cell migration and reflection of internal and external light. The evolution of intraocular lens and extracapsular cataract surgery has lead to faster postoperative recovery and better visual outcomes.

  1. Theory and Computational Design of Protein Materials

    NASA Astrophysics Data System (ADS)

    Saven, Jeffery

    2015-03-01

    Protein design opens routes to arrive at novel molecules, materials and nanostructures. Recent theoretical methods can identify the properties of amino acid sequences consistent with desired structures and functions. Such methods leverage concepts from statistical mechanics and address the structural complexity of proteins and their many possible amino acid sequences. Computationally designed protein-based systems have been experimentally realized to encapsulate nonbiological cofactors and assemble into predetermined crystalline structures.

  2. Materials design for electrocatalytic carbon capture

    NASA Astrophysics Data System (ADS)

    Tan, Xin; Tahini, Hassan A.; Smith, Sean C.

    2016-05-01

    We discuss our philosophy for implementation of the Materials Genome Initiative through an integrated materials design strategy, exemplified here in the context of electrocatalytic capture and separation of CO2 gas. We identify for a group of 1:1 X-N graphene analogue materials that electro-responsive switchable CO2 binding behavior correlates with a change in the preferred binding site from N to the adjacent X atom as negative charge is introduced into the system. A reconsideration of conductive N-doped graphene yields the discovery that the N-dopant is able to induce electrocatalytic binding of multiple CO2 molecules at the adjacent carbon sites.

  3. Carbon nanotube materials characterization and devices design

    NASA Astrophysics Data System (ADS)

    Li, Weifeng

    The objective of this research is to characterize the electrical and mechanical properties of Carbon Nanotube (CNT) materials, and explore possible device applications for these materials. In order to achieve this goal, different forms of Carbon Nanotube materials---including Carbon Nanotubes, Carbon Nanotube Arrays, Carbon Nanotube Ribbon, Carbon Nanotube Thread, and sub-micrometer Carbon Nanotube Thread---were tested under a Scanning Electron Microscope (SEM) using a Micromanipulator (MM). Video and sound recording of the testing in the microscope provided new understanding how thread is formed and how nanotube materials fail. As-produced and thermally treated nanotubes were also tested. The main electrical parameters measured were electrical resistivity and maximum current density. The main mechanical property measured was strength. Together, these parameters are helping to determine the strongest and most conductive forms of CNT material. Putting nanotube materials into application is the ultimate goal of this continuing research. Several aggressive application ideas were investigated in a preliminary way in this work. In biomedical applications, a bundle of CNTs was formed for use as an electrode for accurate biosensing. A simple robot was designed using CNT electrical fiber. The robot was powered by two solenoids and could act as an in-body sensor and actuator to perform some impossible tasks from the viewpoint of current medical technology. In aerospace engineering, CNT materials could replace copper wire to reduce the weight of aircraft. Based on the excellent mechanical properties of CNT materials, a challenging idea is to use CNT material to build elevators to move payloads to outer space without using rockets. This dissertation makes contributions in the characterization of nanotube materials and in the design of miniature electromagnetic devices.

  4. Adaptive Strategies for Materials Design using Uncertainties

    NASA Astrophysics Data System (ADS)

    Balachandran, Prasanna V.; Xue, Dezhen; Theiler, James; Hogden, John; Lookman, Turab

    2016-01-01

    We compare several adaptive design strategies using a data set of 223 M2AX family of compounds for which the elastic properties [bulk (B), shear (G), and Young’s (E) modulus] have been computed using density functional theory. The design strategies are decomposed into an iterative loop with two main steps: machine learning is used to train a regressor that predicts elastic properties in terms of elementary orbital radii of the individual components of the materials; and a selector uses these predictions and their uncertainties to choose the next material to investigate. The ultimate goal is to obtain a material with desired elastic properties in as few iterations as possible. We examine how the choice of data set size, regressor and selector impact the design. We find that selectors that use information about the prediction uncertainty outperform those that don’t. Our work is a step in illustrating how adaptive design tools can guide the search for new materials with desired properties.

  5. Adaptive Strategies for Materials Design using Uncertainties

    PubMed Central

    Balachandran, Prasanna V.; Xue, Dezhen; Theiler, James; Hogden, John; Lookman, Turab

    2016-01-01

    We compare several adaptive design strategies using a data set of 223 M2AX family of compounds for which the elastic properties [bulk (B), shear (G), and Young’s (E) modulus] have been computed using density functional theory. The design strategies are decomposed into an iterative loop with two main steps: machine learning is used to train a regressor that predicts elastic properties in terms of elementary orbital radii of the individual components of the materials; and a selector uses these predictions and their uncertainties to choose the next material to investigate. The ultimate goal is to obtain a material with desired elastic properties in as few iterations as possible. We examine how the choice of data set size, regressor and selector impact the design. We find that selectors that use information about the prediction uncertainty outperform those that don’t. Our work is a step in illustrating how adaptive design tools can guide the search for new materials with desired properties. PMID:26792532

  6. Adaptive strategies for materials design using uncertainties

    DOE PAGESBeta

    Balachandran, Prasanna V.; Xue, Dezhen; Theiler, James; Hogden, John; Lookman, Turab

    2016-01-21

    Here, we compare several adaptive design strategies using a data set of 223 M2AX family of compounds for which the elastic properties [bulk (B), shear (G), and Young’s (E) modulus] have been computed using density functional theory. The design strategies are decomposed into an iterative loop with two main steps: machine learning is used to train a regressor that predicts elastic properties in terms of elementary orbital radii of the individual components of the materials; and a selector uses these predictions and their uncertainties to choose the next material to investigate. The ultimate goal is to obtain a material withmore » desired elastic properties in as few iterations as possible. We examine how the choice of data set size, regressor and selector impact the design. We find that selectors that use information about the prediction uncertainty outperform those that don’t. Our work is a step in illustrating how adaptive design tools can guide the search for new materials with desired properties.« less

  7. A Bridge for Accelerating Materials by Design

    SciTech Connect

    Sumpter, Bobby G.; Vasudevan, Rama K.; Potok, Thomas E.; Kalinin, Sergei V.

    2015-11-25

    Recent technical advances in the area of nanoscale imaging, spectroscopy, and scattering/diffraction have led to unprecedented capabilities for investigating materials structural, dynamical and functional characteristics. In addition, recent advances in computational algorithms and computer capacities that are orders of magnitude larger/faster have enabled large-scale simulations of materials properties starting with nothing but the identity of the atomic species and the basic principles of quantum- and statistical-mechanics and thermodynamics. Along with these advances, an explosion of high-resolution data has emerged. This confluence of capabilities and rise of big data offer grand opportunities for advancing materials sciences but also introduce several challenges. In this editorial we identify challenges impeding progress towards advancing materials by design (e.g., the design/discovery of materials with improved properties/performance), possible solutions, and provide examples of scientific issues that can be addressed by using a tightly integrated approach where theory and experiments are linked through big-deep data.

  8. A Bridge for Accelerating Materials by Design

    DOE PAGESBeta

    Sumpter, Bobby G.; Vasudevan, Rama K.; Potok, Thomas E.; Kalinin, Sergei V.

    2015-11-25

    Recent technical advances in the area of nanoscale imaging, spectroscopy, and scattering/diffraction have led to unprecedented capabilities for investigating materials structural, dynamical and functional characteristics. In addition, recent advances in computational algorithms and computer capacities that are orders of magnitude larger/faster have enabled large-scale simulations of materials properties starting with nothing but the identity of the atomic species and the basic principles of quantum- and statistical-mechanics and thermodynamics. Along with these advances, an explosion of high-resolution data has emerged. This confluence of capabilities and rise of big data offer grand opportunities for advancing materials sciences but also introduce several challenges.more » In this editorial we identify challenges impeding progress towards advancing materials by design (e.g., the design/discovery of materials with improved properties/performance), possible solutions, and provide examples of scientific issues that can be addressed by using a tightly integrated approach where theory and experiments are linked through big-deep data.« less

  9. Progress in material design for biomedical applications.

    PubMed

    Tibbitt, Mark W; Rodell, Christopher B; Burdick, Jason A; Anseth, Kristi S

    2015-11-24

    Biomaterials that interface with biological systems are used to deliver drugs safely and efficiently; to prevent, detect, and treat disease; to assist the body as it heals; and to engineer functional tissues outside of the body for organ replacement. The field has evolved beyond selecting materials that were originally designed for other applications with a primary focus on properties that enabled restoration of function and mitigation of acute pathology. Biomaterials are now designed rationally with controlled structure and dynamic functionality to integrate with biological complexity and perform tailored, high-level functions in the body. The transition has been from permissive to promoting biomaterials that are no longer bioinert but bioactive. This perspective surveys recent developments in the field of polymeric and soft biomaterials with a specific emphasis on advances in nano- to macroscale control, static to dynamic functionality, and biocomplex materials.

  10. Progress in material design for biomedical applications

    PubMed Central

    Tibbitt, Mark W.; Rodell, Christopher B.; Burdick, Jason A.; Anseth, Kristi S.

    2015-01-01

    Biomaterials that interface with biological systems are used to deliver drugs safely and efficiently; to prevent, detect, and treat disease; to assist the body as it heals; and to engineer functional tissues outside of the body for organ replacement. The field has evolved beyond selecting materials that were originally designed for other applications with a primary focus on properties that enabled restoration of function and mitigation of acute pathology. Biomaterials are now designed rationally with controlled structure and dynamic functionality to integrate with biological complexity and perform tailored, high-level functions in the body. The transition has been from permissive to promoting biomaterials that are no longer bioinert but bioactive. This perspective surveys recent developments in the field of polymeric and soft biomaterials with a specific emphasis on advances in nano- to macroscale control, static to dynamic functionality, and biocomplex materials. PMID:26598696

  11. Thermoplastics as engineering materials: The mechanics, materials, design, processing link

    SciTech Connect

    Stokes, V.K.

    1995-10-01

    While the use of plastics has been growing at a significant pace because of weight reduction, ease of fabrication of complex shapes, and cost reduction resulting from function integration, the engineering applications of plastics have only become important in the past fifteen years. An inadequate understanding of the mechanics issues underlying the close coupling among the design, the processing (fabrication), and the assembly with these materials is a barrier to their use in structural applications. Recent progress on some issues relating to the engineering uses of plastics is surveyed, highlighting the need for a better understanding of plastics and how processing affects the performance of plastic parts. Topics addressed include the large deformation behavior of ductile resins, fiber orientation in chopped-fiber filled materials, structural foams, random glass mat composites, modeling of thickness distributions in blow-molded and thermoformed parts, dimensional stability (shrinkage, warpage, and residual stresses) in injection-molded parts, and welding of thermoplastics.

  12. Saving Material with Systematic Process Designs

    NASA Astrophysics Data System (ADS)

    Kerausch, M.

    2011-08-01

    Global competition is forcing the stamping industry to further increase quality, to shorten time-to-market and to reduce total cost. Continuous balancing between these classical time-cost-quality targets throughout the product development cycle is required to ensure future economical success. In today's industrial practice, die layout standards are typically assumed to implicitly ensure the balancing of company specific time-cost-quality targets. Although die layout standards are a very successful approach, there are two methodical disadvantages. First, the capabilities for tool design have to be continuously adapted to technological innovations; e.g. to take advantage of the full forming capability of new materials. Secondly, the great variety of die design aspects have to be reduced to a generic rule or guideline; e.g. binder shape, draw-in conditions or the use of drawbeads. Therefore, it is important to not overlook cost or quality opportunities when applying die design standards. This paper describes a systematic workflow with focus on minimizing material consumption. The starting point of the investigation is a full process plan for a typical structural part. All requirements are definedaccording to a predefined set of die design standards with industrial relevance are fulfilled. In a first step binder and addendum geometry is systematically checked for material saving potentials. In a second step, blank shape and draw-in are adjusted to meet thinning, wrinkling and springback targets for a minimum blank solution. Finally the identified die layout is validated with respect to production robustness versus splits, wrinkles and springback. For all three steps the applied methodology is based on finite element simulation combined with a stochastical variation of input variables. With the proposed workflow a well-balanced (time-cost-quality) production process assuring minimal material consumption can be achieved.

  13. Designer self-assembling peptide materials.

    PubMed

    Zhao, Xiaojun; Zhang, Shuguang

    2007-01-01

    Understanding of macromolecular materials at the molecular level is becoming increasingly important for a new generation of nanomaterials for nanobiotechnology and other disciplines, namely, the design, synthesis, and fabrication of nanodevices at the molecular scale from bottom up. Basic engineering principles for microfabrication can be learned through fully grasping the molecular self-assembly and programmed assembly phenomena. Self- and programmed-assembly phenomena are ubiquitous in nature. Two key elements in molecular macrobiological material productions are chemical complementarity and structural compatibility, both of which require weak and non-covalent interactions that bring building blocks together during self-assembly. Significant advances have been made during the 1990s at the interface of materials chemistry and biology. They include the design of helical ribbons, peptide nanofiber scaffolds for three-dimensional cell cultures and tissue engineering, peptide surfactants for solubilizing and stabilizing diverse types of membrane proteins and their complexes, and molecular ink peptides for arbitrary printing and coating surfaces as well as coiled-coil helical peptides for multi-length scale fractal structures. These designer self-assembling peptides have far reaching implications in a broad spectrum of applications in biology, medicine, nanobiotechnology, and nanobiomedical technology, some of which are beyond our current imaginations. [image: see text

  14. Computational Materials Program for Alloy Design

    NASA Technical Reports Server (NTRS)

    Bozzolo, Guillermo

    2005-01-01

    The research program sponsored by this grant, "Computational Materials Program for Alloy Design", covers a period of time of enormous change in the emerging field of computational materials science. The computational materials program started with the development of the BFS method for alloys, a quantum approximate method for atomistic analysis of alloys specifically tailored to effectively deal with the current challenges in the area of atomistic modeling and to support modern experimental programs. During the grant period, the program benefited from steady growth which, as detailed below, far exceeds its original set of goals and objectives. Not surprisingly, by the end of this grant, the methodology and the computational materials program became an established force in the materials communitiy, with substantial impact in several areas. Major achievements during the duration of the grant include the completion of a Level 1 Milestone for the HITEMP program at NASA Glenn, consisting of the planning, development and organization of an international conference held at the Ohio Aerospace Institute in August of 2002, finalizing a period of rapid insertion of the methodology in the research community worlwide. The conference, attended by citizens of 17 countries representing various fields of the research community, resulted in a special issue of the leading journal in the area of applied surface science. Another element of the Level 1 Milestone was the presentation of the first version of the Alloy Design Workbench software package, currently known as "adwTools". This software package constitutes the first PC-based piece of software for atomistic simulations for both solid alloys and surfaces in the market.Dissemination of results and insertion in the materials community worldwide was a primary focus during this period. As a result, the P.I. was responsible for presenting 37 contributed talks, 19 invited talks, and publishing 71 articles in peer-reviewed journals, as

  15. Application of New Materials in the Household Appliances Design

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Ren, Y.

    The widespread use of new materials in household appliances industry, not only help those products to get rid of the appearance shackles caused by original materials, but also gave the designers the freedom to open up the world of product design. This paper aims to analyze the impact of new materials for home appliances design through relevant research, to explore the application of new material in household appliances functional design, shape design, color design and emotional design, etc., so as to reveal the impact and promoting effects of new material in household appliances world, as well as the prospects of new material in future household appliances design.

  16. Materials by Design: Merging Proteins and Music.

    PubMed

    Wong, Joyce Y; McDonald, John; Taylor-Pinney, Micki; Spivak, David I; Kaplan, David L; Buehler, Markus J

    2012-12-01

    Tailored materials with tunable properties are crucial for applications as biomaterials, for drug delivery, as functional coatings, or as lightweight composites. An emerging paradigm in designing such materials is the construction of hierarchical assemblies of simple building blocks into complex architectures with superior properties. We review this approach in a case study of silk, a genetically programmable and processable biomaterial, which, in its natural role serves as a versatile protein fiber with hierarchical organization to provide structural support, prey procurement or protection of eggs. Through an abstraction of knowledge from the physical system, silk, to a mathematical model using category theory, we describe how the mechanism of spinning fibers from proteins can be translated into music through a process that assigns a set of rules that governs the construction of the system. This technique allows one to express the structure, mechanisms and properties of the 'material' in a very different domain, 'music'. The integration of science and art through categorization of structure-property relationships presents a novel paradigm to create new bioinspired materials, through the translation of structures and mechanisms from distinct hierarchical systems and in the context of the limited number of building blocks that universally governs these systems. PMID:23997808

  17. Computational design of microvascular biomimetic materials

    NASA Astrophysics Data System (ADS)

    Aragon, Alejandro Marcos

    Biomimetic microvascular materials are increasingly considered for a variety of autonomic healing, cooling and sensing applications. The microvascular material of interest in this work consists of a network of hollow microchannels, with diameters as small as 10 mum, embedded in a polymeric matrix. Recent advances in the manufacturing of this new class of materials have allowed for the creation of very complex 2D and 3D structures. The computational design of such network structures, which is the focus of this work, involves a set of particular challenges, including a large number of design variables (e.g., topology of the network, number of diameters to consider and their sizes) that define the network, and a large number of multidisciplinary objective functions and constraints that drive the optimization process. The computational design tool to be developed must be capable of capturing the trade-off between the different objective and constraint functions, as, for example, networks designed for flow efficiency are likely to have a topology that is very different from those designed for structural integrity or thermal control. In this work, we propose to design these materials using Genetic Algorithms (GAs), the most common methodology within a broader category of Evolutionary Algorithms (EAs). GAs can be combined with a Pareto-selection mechanism to create Multi-Objective Genetic Algorithms (MOGAs), which enable the optimization of an arbitrary number of objective functions. As a result, a Pareto-optimal front is obtained, where all candidates are optimal solutions to the optimization problem. Adding a procedure to deal with constraints results in a powerful tool for multi-objective constrained optimization. The method allows the use of discrete variable problems and it does not require any a priori knowledge of the optimal solution. Furthermore, GAs search the entire decision space so the optimal solutions found are likely to be global. The

  18. Materials by Design: Merging Proteins and Music

    PubMed Central

    Wong, Joyce Y.; McDonald, John; Taylor-Pinney, Micki; Spivak, David I.; Kaplan, David L.; Buehler, Markus J.

    2013-01-01

    Tailored materials with tunable properties are crucial for applications as biomaterials, for drug delivery, as functional coatings, or as lightweight composites. An emerging paradigm in designing such materials is the construction of hierarchical assemblies of simple building blocks into complex architectures with superior properties. We review this approach in a case study of silk, a genetically programmable and processable biomaterial, which, in its natural role serves as a versatile protein fiber with hierarchical organization to provide structural support, prey procurement or protection of eggs. Through an abstraction of knowledge from the physical system, silk, to a mathematical model using category theory, we describe how the mechanism of spinning fibers from proteins can be translated into music through a process that assigns a set of rules that governs the construction of the system. This technique allows one to express the structure, mechanisms and properties of the ‘material’ in a very different domain, ‘music’. The integration of science and art through categorization of structure-property relationships presents a novel paradigm to create new bioinspired materials, through the translation of structures and mechanisms from distinct hierarchical systems and in the context of the limited number of building blocks that universally governs these systems. PMID:23997808

  19. Designer protein-based performance materials.

    PubMed

    Kumar, Manoj; Sanford, Karl J; Cuevas, William A; Cuevas, William P; Du, Mai; Collier, Katharine D; Chow, Nicole

    2006-09-01

    Repeat sequence protein polymer (RSPP) technology provides a platform to design and make protein-based performance polymers and represents the best nature has to offer. We report here that the RSPP platform is a novel approach to produce functional protein polymers that have both biomechanical and biofunctional blocks built into one molecule by design, using peptide motifs. We have shown that protein-based designer biopolymers can be made using recombinant DNA technology and fermentation and offer the ability to screen for desired properties utilizing the tremendous potential diversity of amino acid combinations. The technology also allows for large-scale manufacturing with a favorable fermentative cost-structure to deliver commercially viable performance polymers. Using three diverse examples with antimicrobial, textile targeting, and UV-protective agent, we have introduced functional attributes into structural protein polymers and shown, for example, that the functionalized RSPPs have possible applications in biodefense, industrial biotechnology, and personal care areas. This new class of biobased materials will simulate natural biomaterials that can be modified for desired function and have many advantages over conventional petroleum-based polymers.

  20. 14 CFR 25.613 - Material strength properties and material design values.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Material strength properties and material... § 25.613 Material strength properties and material design values. (a) Material strength properties must be based on enough tests of material meeting approved specifications to establish design values on...

  1. 14 CFR 25.613 - Material strength properties and material design values.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Material strength properties and material... § 25.613 Material strength properties and material design values. (a) Material strength properties must be based on enough tests of material meeting approved specifications to establish design values on...

  2. 14 CFR 25.613 - Material strength properties and material design values.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Material strength properties and material... § 25.613 Material strength properties and material design values. (a) Material strength properties must be based on enough tests of material meeting approved specifications to establish design values on...

  3. 14 CFR 25.613 - Material strength properties and material design values.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Material strength properties and material... § 25.613 Material strength properties and material design values. (a) Material strength properties must be based on enough tests of material meeting approved specifications to establish design values on...

  4. The artificial disc: theory, design and materials.

    PubMed

    Bao, Q B; McCullen, G M; Higham, P A; Dumbleton, J H; Yuan, H A

    1996-06-01

    Low back pain is one of the most common medical conditions in the Western world. Disc degeneration, an inevitable process of aging, of variable rate and degree, is one of the major causes of low back pain. Currently, there are two major surgical interventions for treating conditions related to the degenerative disc: discectomy and fusion. Although discectomy and fusion produce a relatively good short-term clinical result in relieving pain, both these surgical treatments alter the biomechanics of the spine, possibly leading to further degeneration of the surrounding tissues and the discs at adjacent levels. Over the past 35 years, a tremendous effort has been made to develop an artificial disc to replace the degenerated disc. The goal is the restoration of the natural biomechanics of the segment after disc excision, thus relieving pain and preventing further degeneration at adjacent segments. However, the artificial disc faces a complex biomechanical environment which makes replication of the biomechanics difficult and long-term survival challenging to designs and materials. The purpose of this article is to examine the factors of importance in designing a disc replacement. Topics covered include the structure and function of the natural disc, the changes that occur with disc degeneration and existing methods of treatment for the degenerative spine. The progress in achieving a functional, long-lasting disc replacement is outlined.

  5. Tools for Material Design and Selection

    NASA Astrophysics Data System (ADS)

    Wehage, Kristopher

    The present thesis focuses on applications of numerical methods to create tools for material characterization, design and selection. The tools generated in this work incorporate a variety of programming concepts, from digital image analysis, geometry, optimization, and parallel programming to data-mining, databases and web design. The first portion of the thesis focuses on methods for characterizing clustering in bimodal 5083 Aluminum alloys created by cryomilling and powder metallurgy. The bimodal samples analyzed in the present work contain a mixture of a coarse grain phase, with a grain size on the order of several microns, and an ultra-fine grain phase, with a grain size on the order of 200 nm. The mixing of the two phases is not homogeneous and clustering is observed. To investigate clustering in these bimodal materials, various microstructures were created experimentally by conventional cryomilling, Hot Isostatic Pressing (HIP), Extrusion, Dual-Mode Dynamic Forging (DMDF) and a new 'Gradient' cryomilling process. Two techniques for quantitative clustering analysis are presented, formulated and implemented. The first technique, the Area Disorder function, provides a metric of the quality of coarse grain dispersion in an ultra-fine grain matrix and the second technique, the Two-Point Correlation function, provides a metric of long and short range spatial arrangements of the two phases, as well as an indication of the mean feature size in any direction. The two techniques are implemented on digital images created by Scanning Electron Microscopy (SEM) and Electron Backscatter Detection (EBSD) of the microstructures. To investigate structure--property relationships through modeling and simulation, strategies for generating synthetic microstructures are discussed and a computer program that generates randomized microstructures with desired configurations of clustering described by the Area Disorder Function is formulated and presented. In the computer program, two

  6. 46 CFR 58.05-1 - Material, design and construction.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Material, design and construction. 58.05-1 Section 58.05... AUXILIARY MACHINERY AND RELATED SYSTEMS Main Propulsion Machinery § 58.05-1 Material, design and construction. (a) The material, design, construction, workmanship, and arrangement of main propulsion...

  7. 46 CFR 58.05-1 - Material, design and construction.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Material, design and construction. 58.05-1 Section 58.05... AUXILIARY MACHINERY AND RELATED SYSTEMS Main Propulsion Machinery § 58.05-1 Material, design and construction. (a) The material, design, construction, workmanship, and arrangement of main propulsion...

  8. 46 CFR 58.05-1 - Material, design and construction.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Material, design and construction. 58.05-1 Section 58.05... AUXILIARY MACHINERY AND RELATED SYSTEMS Main Propulsion Machinery § 58.05-1 Material, design and construction. (a) The material, design, construction, workmanship, and arrangement of main propulsion...

  9. 46 CFR 58.05-1 - Material, design and construction.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Material, design and construction. 58.05-1 Section 58.05... AUXILIARY MACHINERY AND RELATED SYSTEMS Main Propulsion Machinery § 58.05-1 Material, design and construction. (a) The material, design, construction, workmanship, and arrangement of main propulsion...

  10. 46 CFR 58.05-1 - Material, design and construction.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Material, design and construction. 58.05-1 Section 58.05... AUXILIARY MACHINERY AND RELATED SYSTEMS Main Propulsion Machinery § 58.05-1 Material, design and construction. (a) The material, design, construction, workmanship, and arrangement of main propulsion...

  11. Learning from systems biology: An ``Omics'' approach to materials design

    NASA Astrophysics Data System (ADS)

    Rajan, Krishna

    2008-03-01

    An understanding of systems biology provides an excellent paradigm for the materials scientist. Ultimately one would like to take an “atoms-applications” approach to materials design. This paper describes how the concepts of genomics, proteomics, and other biological behavior which form the foundations of modern biology can be applied to materials design through materials informatics.

  12. Design concepts for pressurized lunar shelters utilizing indigenous materials

    NASA Technical Reports Server (NTRS)

    Happel, John Amin; Willam, Kaspar; Shing, Benson

    1991-01-01

    The objective is to design a pressurized shelter build of indigenous lunar material. The topics are presented in viewgraph form and include the following: lunar conditions which impact design; secondary factors; review of previously proposed concepts; cross section of assembly facility; rationale for indigenous materials; indigenous material choices; cast basalt properties; design variables; design 1, cylindrical segments; construction sequence; design 2, arch-slabs with post-tensioned ring girders; and future research.

  13. Mass of materials: the impact of designers on construction ergonomics.

    PubMed

    Smallwood, John

    2012-01-01

    Many construction injuries are musculoskeletal related in the form of sprains and strains arising from the handling of materials, which are specified by designers. The paper presents the results of a study conducted among delegates attending two 'designing for H&S' (DfH&S) seminars using a questionnaire. The salient findings include: the level of knowledge relative to the mass and density of materials is limited; designers generally do not consider the mass and density of materials when designing structures and elements and specifying materials; to a degree designers appreciate that the mass and density of materials impact on construction ergonomics; designers rate their knowledge of the mass and density of materials as limited, and designers appreciate the potential of the consideration of the mass and density of materials to contribute to an improvement in construction ergonomics. Conclusions include: designers lack the requisite knowledge relative to the mass and density of materials; designers are thus precluded from conducting optimum design hazard identification and risk assessments, and tertiary built environment designer education does not enlighten designers relative to construction ergonomics. Recommendations include: tertiary built environment designer education should construction ergonomics; professional associations should raise the level of awareness relative to construction ergonomics, and design practices should include a category 'mass and density of materials' in their practice libraries.

  14. Porous materials. Function-led design of new porous materials.

    PubMed

    Slater, Anna G; Cooper, Andrew I

    2015-05-29

    Porous solids are important as membranes, adsorbents, catalysts, and in other chemical applications. But for these materials to find greater use at an industrial scale, it is necessary to optimize multiple functions in addition to pore structure and surface area, such as stability, sorption kinetics, processability, mechanical properties, and thermal properties. Several different classes of porous solids exist, and there is no one-size-fits-all solution; it can therefore be challenging to choose the right type of porous material for a given job. Computational prediction of structure and properties has growing potential to complement experiment to identify the best porous materials for specific applications.

  15. Material for Point Design (final summary of DIME material)

    SciTech Connect

    Bradley, Paul A.

    2014-02-25

    These slides summarize the motivation of the Defect Induced Mix Experiment (DIME) project, the “point design” of the Polar Direct Drive (PDD) version of the NIF separated reactant capsule, the experimental requirements, technical achievements, and some useful backup material. These slides are intended to provide much basic material in one convenient location and will hopefully be of some use for subsequent experimental projects.

  16. Nanoscale material design for photovoltaic applications

    NASA Astrophysics Data System (ADS)

    Bao, Hua

    /nanowire array solar cells. Phonon-assisted electron decay in semiconductor quantum dots is also investigated in this work. In semiconductor solar cell, a large portion of energy loss is by the fast hot electron cooling, in which a high energy electron decays to the electronic band gap by creating a series of phonons. The excessive electrical energy is then converted to heat and wasted, so that the total photovoltaic energy conversion efficiency is limited. The electron decay rate reduces in semiconductor quantum dots, due to the discrete electron energy levels created by quantum confinement. To design quantum dots with the slowest decay rate, we use the non-adiabatic molecular dynamics to perform real-time simulations of the phonon-assisted electron decay process. This method is based on time-dependent density functional theory, and can directly predict the phonon-assisted electron decay time using the initial quantum dot structure as the only input. The numerical simulation shows that the phonon-induced electron decay can be slowed down in a small PbSe quantum dot. The temperature-dependent relaxation in this quantum dot is also studied, which helps us to propose a multi-channel relaxation mechanism. This mechanism provides new insights to the understanding of electron decay process in quantum dots. The results from this study have potentially important applications in solar energy harvesting and radiative thermal management. It offers a new perspective of nanoscale engineering of materials to achieve more efficient photovoltaic energy conversion.

  17. Diamond detector - material science, design and application

    NASA Astrophysics Data System (ADS)

    Gaowei, Mengjia

    Modern synchrotrons, such as the NSLS-II, will enable unprecedented science by having extremely high brightness and flux with exceptional beam stability. These capabilities create a harsh and demanding environment for measuring the characteristics of the x-ray beam. In many cases, existing measurement techniques fail completely, requiring the development of new detectors which can meet the demands of the synchrotron. The combination of diamond properties ranked diamond an appealing candidate in the field of radiation detection in extreme conditions and it has been used as x-ray sensor material for decades. However, only until the development of chemical vapor deposition (CVD) process in the synthesis of diamond that has it been considered for wider applications in the state-of-art synchrotron light sources as part of beamline diagnostics, including the detection of x-ray beam flux and position. While defects and dislocations in CVD grown single crystal diamonds are inevitable, there are solutions in other aspects of a device fabrication to compensate this technological downside, including improving device performance in engineering diamond surface electrode materials and patterns and slicing and polishing diamond plates into thinner pieces. The content of this dissertation summarizes our effort in addressing several problems we encounter in the process of design and fabrication of single crystal CVD diamond based electronic devices. In order to study the generation of post-anneal photoconductive gain in our devices we have discussed in section 3 and 4 the two criteria for the observation of photoconductive current. In section 3 we reveal the correlation between structural defects in diamond and the post-anneal photoconductive regions. Section 4 introduces the measurements of hard x-ray photoelectron spectroscopy (HAXPES) we applied to investigate the diamond-metal Schottky barrier height for several metals and diamond surface terminations. The position of the

  18. FOREWORD: Computational methodologies for designing materials Computational methodologies for designing materials

    NASA Astrophysics Data System (ADS)

    Rahman, Talat S.

    2009-02-01

    It would be fair to say that in the past few decades, theory and computer modeling have played a major role in elucidating the microscopic factors that dictate the properties of functional novel materials. Together with advances in experimental techniques, theoretical methods are becoming increasingly capable of predicting properties of materials at different length scales, thereby bringing in sight the long-sought goal of designing material properties according to need. Advances in computer technology and their availability at a reasonable cost around the world have made tit all the more urgent to disseminate what is now known about these modern computational techniques. In this special issue on computational methodologies for materials by design we have tried to solicit articles from authors whose works collectively represent the microcosm of developments in the area. This turned out to be a difficult task for a variety of reasons, not the least of which is space limitation in this special issue. Nevertheless, we gathered twenty articles that represent some of the important directions in which theory and modeling are proceeding in the general effort to capture the ability to produce materials by design. The majority of papers presented here focus on technique developments that are expected to uncover further the fundamental processes responsible for material properties, and for their growth modes and morphological evolutions. As for material properties, some of the articles here address the challenges that continue to emerge from attempts at accurate descriptions of magnetic properties, of electronically excited states, and of sparse matter, all of which demand new looks at density functional theory (DFT). I should hasten to add that much of the success in accurate computational modeling of materials emanates from the remarkable predictive power of DFT, without which we would not be able to place the subject on firm theoretical grounds. As we know and will also

  19. An educational program on structural design with brittle /ceramic/ materials

    NASA Technical Reports Server (NTRS)

    Mueller, J. I.

    1978-01-01

    The organization of a proposed ceramic structural materials program is described, and a suggested course sequence for college-level and graduate-level courses is presented. The course work on ceramics and brittle fracture are intended to lead to a brittle material design project and a brittle material design problem. Criteria for the selection of appropriate projects/problems are considered.

  20. Space & Materials: A Second Year Design Curriculum.

    ERIC Educational Resources Information Center

    Ziff, Matthew

    Design students provide a constant source of energy that moves into the mainstream of society. Their energy needs to be directed toward improving the characteristics of the built environment at every physical and economic scale of activity. Teaching design involves a broad range of decisions on how to present relevant design education content to…

  1. Writing and designing readable patient education materials.

    PubMed

    Aldridge, Michael D

    2004-01-01

    Functional illiteracy is a problem often overlooked by nurses. Although the average adult in the United States cannot read above the eighth-grade level, most patient education materials are written on a high-school or college reading level. If patients cannot read educational materials, then there is little hope of them using or understanding the information. Strategies for improving the readability of education materials specific to the needs of nephrology patients are discussed in this article.

  2. 14 CFR 25.613 - Material strength properties and material design values.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... individual item is tested before use to determine that the actual strength properties of that particular item... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Material strength properties and material... § 25.613 Material strength properties and material design values. (a) Material strength properties...

  3. Synthesis and design of silicide intermetallic materials

    SciTech Connect

    Petrovic, J.J.; Castro, R.G.; Butt, D.P.; Park, Y.; Hollis, K.J.; Kung, H.H.

    1998-11-01

    The overall objective of this program is to develop structural silicide-based materials with optimum combinations of elevated temperature strength/creep resistance, low temperature fracture toughness, and high temperature oxidation and corrosion resistance for applications of importance to the U.S. processing industry. A further objective is to develop silicide-based prototype industrial components. The ultimate aim of the program is to work with industry to transfer the structural silicide materials technology to the private sector in order to promote international competitiveness in the area of advanced high temperature materials and important applications in major energy-intensive U.S. processing industries.

  4. Design for containment of hazardous materials

    SciTech Connect

    Murray, R.C. ); McDonald, J.R. )

    1991-03-01

    Department of Energy, (DOE), facilities across the United States, use wind and tornado design and evaluation criteria based on probabilistic performance goals. In addition, other programs such as Advanced Light Water Reactors, New Production Reactors, and Individual Plant Examinations for External Events for commercial nuclear power plants utilize design and evaluation criteria based on probabilistic performance goals. The use of probabilistic performance goals is a departure from design practice for commercial nuclear power plants which have traditionally been designed utilizing a conservative specification of wind and tornado loading combined with deterministic response evaluation methods and permissible behavior limits. Approaches which utilize probabilistic wind and tornado hazard curves for specification of loading and deterministic response evaluation methods and permissible behavior limits are discussed in this paper. Through the use of such design/evaluation approaches, it may be demonstrated that there is high likelihood that probabilistic performance goals can be achieved. 14 refs., 1 fig., 5 tabs.

  5. Materials Design On-the-Fly.

    PubMed

    Cerqueira, Tiago F T; Sarmiento-Pérez, Rafael; Amsler, Maximilian; Nogueira, F; Botti, Silvana; Marques, Miguel A L

    2015-08-11

    The dream of any solid-state theorist is to be able to predict new materials with tailored properties from scratch, i.e., without any input from experiment. Over the past decades, we have steadily approached this goal. Recent developments in the field of high-throughput calculations focused on finding the best material for specific applications. However, a key input for these techniques still had to be obtained experimentally, namely, the crystal structure of the materials. Here, we give a step further and show that one can indeed optimize material properties using as a single starting point the knowledge of the periodic table and the fundamental laws of quantum mechanics. This is done by combining state-of-the-art methods of global structure prediction that allow us to obtain the ground-state crystal structure of arbitrary materials, with an evolutionary algorithm that optimizes the chemical composition for the desired property. As a first showcase demonstration of our method, we perform an unbiased search for superhard materials and for transparent conductors. We stress that our method is completely general and can be used to optimize any property (or combination of properties) that can be calculated in a computer. PMID:26574474

  6. Synthesis and design of silicide intermetallic materials

    SciTech Connect

    Petrovic, J.J.; Castro, R.G.; Butt, D.P.

    1997-04-01

    The overall objective of this program is to develop structural silicide-based materials with optimum combinations of elevated temperature strength/creep resistance, low temperature fracture toughness, and high temperature oxidation and corrosion resistance for applications of importance to the U.S. processing industry. A further objective is to develop silicide-based prototype industrial components. The ultimate aim of the program is to work with industry to transfer the structural silicide materials technology to the private sector in order to promote international competitiveness in the area of advanced high temperature materials and important applications in major energy-intensive U.S. processing industries. The program presently has a number of developing industrial connections, including a CRADA with Schuller International Inc. targeted at the area of MoSi{sub 2}-based high temperature materials and components for fiberglass melting and processing applications. The authors are also developing an interaction with the Institute of Gas Technology (IGT) to develop silicides for high temperature radiant gas burner applications, for the glass and other industries. Current experimental emphasis is on the development and characterization of MoSi{sub 2}-Si{sub 3}N{sub 4} and MoSi{sub 2}-SiC composites, the plasma spraying of MoSi{sub 2}-based materials, and the joining of MoSi{sub 2} materials to metals.

  7. Materials Design On-the-Fly.

    PubMed

    Cerqueira, Tiago F T; Sarmiento-Pérez, Rafael; Amsler, Maximilian; Nogueira, F; Botti, Silvana; Marques, Miguel A L

    2015-08-11

    The dream of any solid-state theorist is to be able to predict new materials with tailored properties from scratch, i.e., without any input from experiment. Over the past decades, we have steadily approached this goal. Recent developments in the field of high-throughput calculations focused on finding the best material for specific applications. However, a key input for these techniques still had to be obtained experimentally, namely, the crystal structure of the materials. Here, we give a step further and show that one can indeed optimize material properties using as a single starting point the knowledge of the periodic table and the fundamental laws of quantum mechanics. This is done by combining state-of-the-art methods of global structure prediction that allow us to obtain the ground-state crystal structure of arbitrary materials, with an evolutionary algorithm that optimizes the chemical composition for the desired property. As a first showcase demonstration of our method, we perform an unbiased search for superhard materials and for transparent conductors. We stress that our method is completely general and can be used to optimize any property (or combination of properties) that can be calculated in a computer.

  8. Thermal Characterization of Functionally Graded Materials: Design of Optimum Experiments

    NASA Technical Reports Server (NTRS)

    Cole, Kevin D.

    2003-01-01

    This paper is a study of optimal experiment design applied to the measure of thermal properties in functionally graded materials. As a first step, a material with linearly-varying thermal properties is analyzed, and several different tran- sient experimental designs are discussed. An optimality criterion, based on sen- sitivity coefficients, is used to identify the best experimental design. Simulated experimental results are analyzed to verify that the identified best experiment design has the smallest errors in the estimated parameters. This procedure is general and can be applied to design of experiments for a variety of materials.

  9. Multilayer filter design with high K materials

    NASA Astrophysics Data System (ADS)

    Curtis, Nathaniel, II

    A novel approach to filter design is presented. A high-K multilayer coupled line filter is designed for optimal performance within a dielectric resonator of rectangular cross section. The multilayer filter is shown to have a performance comparable to its planar counterpart as well as the Lange coupler while maintaining the design advantages that come with the multilayer approach to filter design such as increased flexibility in managing parameter constraints. The performance of the rectangular cross sectioned resonator in terms of modal response and resonant frequency has been evaluated through mathematical derivation and simulation. The reader will find the step by step process to designing the resonant structure as well as a MATLAB script that will graphically display the effect changing various parameters may have on resonator size to assist in the design analysis. The resonator has been designed to provide a finite package in terms of space and performance so that it may house the multilayer filter on a printed circuit board for ease of system implementation. The proposed design with analysis will prove useful for all multilayer coupled line filter types that may take advantage of the uniform environment provided by the finite packaging of the dielectric resonator. As with any microwave system, considerable effort must be put forth to maintain signal integrity throughout the delivery process from the signal input to reception at the output. As a result a large amount of effort and research has gone into answering the question of how to efficiently feed both a dielectric resonator filter of rectangular cross section as well as a coupled line filter that would be embedded within the resonators confines. Several methods for feeding have been explored and reported on. Of the feeding methods reported on the most feasible design includes a unique microstrip delivery to the embedded multilayer filter as pictured here.* *Please refer to dissertation for diagram.

  10. Synthesis and Design of Silicide Intermetallic Materials

    SciTech Connect

    Petrovic, J.J.; Castro, R.G.; Vaidya, R.U.; Park, Y.

    1999-05-14

    The overall objective of this program is to develop structural silicide-based materials with optimum combinations of elevated temperature strength/creep resistance, low temperature fracture toughness, and high temperature oxidation and corrosion resistance for applications of importance to the US processing industry. A further objective is to develop silicide-based prototype industrial components. The ultimate aim of the program is to work with industry to transfer the structural silicide materials technology to the private sector in order to promote international competitiveness in the area of advanced high temperature materials and important applications in major energy-intensive US processing industries. The program presently has a number of industrial connections, including a CRADA with Johns Manville Corporation targeted at the area of MoSi{sub 2}-based high temperature materials for fiberglass melting and processing applications. The authors are also developing an interaction with the Institute of Gas Technology (IGT) to develop silicides for high temperature radiant gas burner applications, for the glass and other industries. With the Exotherm Corporation, they are developing advanced silicide powders for the fabrication of silicide materials with tailored and improved properties for industrial applications. In October 1998, the authors initiated a new activity funded by DOE/OIT on ``Molybdenum Disilicide Composites for Glass Processing Sensors''. With Accutru International Corporation, they are developing silicide-based protective sheaths for self-verifying temperature sensors which may be used in glass furnaces and other industrial applications. With Combustion Technology Inc., they are developing silicide-based periscope sight tubes for the direct observation of glass melts.

  11. Computer-Aided Design Of Sheet-Material Parts

    NASA Technical Reports Server (NTRS)

    Gilbert, Jeffrey L.; Paternoster, Vincent Y.; Levitt, Maureen L.; Osterloh, Mark R.

    1991-01-01

    Computer-aided-design system partly automates tedious process of designing and guiding assembly of small pieces of flat sheet material into large surfaces that approximate smoothly curved surfaces having complicated three-dimensional shapes. Capability provides for flexibility enabling designer to assess quickly and easily effects of changes in design in making engineering compromises among various sizes and shapes. Saves time and money in both design and fabrication. Used in rocket-engine application and other applications requiring design of sheet-material parts.

  12. Evaluating Course Design Principles for Multimedia Learning Materials

    ERIC Educational Resources Information Center

    Scott, Bernard; Cong, Chunyu

    2010-01-01

    Purpose: This paper aims to report on evaluation studies of principles of course design for interactive multimedia learning materials. Design/methodology/approach: At the Defence Academy of the UK, Cranfield University has worked with military colleagues to produce multimedia learning materials for courses on "Military Knowledge". The courses are…

  13. Designed porosity materials in nuclear reactor components

    DOEpatents

    Yacout, A. M.; Pellin, Michael J.; Stan, Marius

    2016-09-06

    A nuclear fuel pellet with a porous substrate, such as a carbon or tungsten aerogel, on which at least one layer of a fuel containing material is deposited via atomic layer deposition, and wherein the layer deposition is controlled to prevent agglomeration of defects. Further, a method of fabricating a nuclear fuel pellet, wherein the method features the steps of selecting a porous substrate, depositing at least one layer of a fuel containing material, and terminating the deposition when the desired porosity is achieved. Also provided is a nuclear reactor fuel cladding made of a porous substrate, such as silicon carbide aerogel or silicon carbide cloth, upon which layers of silicon carbide are deposited.

  14. Designing Training Materials for Developing Countries.

    ERIC Educational Resources Information Center

    Rosenweig, Fred

    1984-01-01

    Describes four training guides developed by the Water and Sanitation for Health Project for use in rural water supply and sanitation projects in developing countries, explains the development process, offers insights gained from the process, and presents five considerations for designing training in third world countries. (MBR)

  15. Designing and modeling doubly porous polymeric materials

    NASA Astrophysics Data System (ADS)

    Ly, H.-B.; Le Droumaguet, B.; Monchiet, V.; Grande, D.

    2015-07-01

    Doubly porous organic materials based on poly(2-hydroxyethyl methacrylate) are synthetized through the use of two distinct types of porogen templates, namely a macroporogen and a nanoporogen. Two complementary strategies are implemented by using either sodium chloride particles or fused poly(methyl methacrylate) beads as macroporogens, in conjunction with ethanol as a porogenic solvent. The porogen removal respectively allows for the generation of either non-interconnected or interconnected macropores with an average diameter of about 100-200 μm and nanopores with sizes lying within the 100 nm order of magnitude, as evidenced by mercury intrusion porosimetry and scanning electron microscopy. Nitrogen sorption measurements evidence the formation of materials with rather high specific surface areas, i.e. higher than 140 m2.g-1. This paper also addresses the development of numerical tools for computing the permeability of such doubly porous materials. Due to the coexistence of well separated scales between nanopores and macropores, a consecutive double homogenization approach is proposed. A nanoscopic scale and a mesoscopic scale are introduced, and the flow is evaluated by means of the Finite Element Method to determine the macroscopic permeability. At the nanoscopic scale, the flow is described by the Stokes equations with an adherence condition at the solid surface. At the mesoscopic scale, the flow obeys the Stokes equations in the macropores and the Darcy equation in the permeable polymer in order to account for the presence of the nanopores.

  16. Teaching-Material Design Center: An Ontology-Based System for Customizing Reusable e-Materials

    ERIC Educational Resources Information Center

    Wang, Hei-Chia; Hsu, Chien-Wei

    2006-01-01

    Use of electronic teaching materials (e-material) to support teaching is a trend. e-Material design is therefore an important issue. Currently, most e-material providers offer a package of solutions for different purposes. However, not all teachers and learners need everything from a single package. A preferable alternative is to find useful…

  17. Concurrent materials and process selection in conceptual design

    SciTech Connect

    Kleban, S.D.

    1998-07-01

    The sequential manner in which materials and processes for a manufactured product are selected is inherently less than optimal. Designers` tendency to choose processes and materials with which they are familiar exacerbate this problem. A method for concurrent selection of materials and a joining process based on product requirements using a knowledge-based, constraint satisfaction approach is presented.

  18. Material Design, Selection, and Manufacturing Methods for System Sustainment

    SciTech Connect

    David Sowder, Jim Lula, Curtis Marshall

    2010-02-18

    This paper describes a material selection and validation process proven to be successful for manufacturing high-reliability long-life product. The National Secure Manufacturing Center business unit of the Kansas City Plant (herein called KCP) designs and manufactures complex electrical and mechanical components used in extreme environments. The material manufacturing heritage is founded in the systems design to manufacturing practices that support the U.S. Department of Energy’s National Nuclear Security Administration (DOE/NNSA). Material Engineers at KCP work with the systems designers to recommend materials, develop test methods, perform analytical analysis of test data, define cradle to grave needs, present final selection and fielding. The KCP material engineers typically will maintain cost control by utilizing commercial products when possible, but have the resources and to develop and produce unique formulations as necessary. This approach is currently being used to mature technologies to manufacture materials with improved characteristics using nano-composite filler materials that will enhance system design and production. For some products the engineers plan and carry out science-based life-cycle material surveillance processes. Recent examples of the approach include refurbished manufacturing of the high voltage power supplies for cockpit displays in operational aircraft; dry film lubricant application to improve bearing life for guided munitions gyroscope gimbals, ceramic substrate design for electrical circuit manufacturing, and tailored polymeric materials for various systems. The following examples show evidence of KCP concurrent design-to-manufacturing techniques used to achieve system solutions that satisfy or exceed demanding requirements.

  19. Materials Selection in Gas Turbine Engine Design and the Role of Low Thermal Expansion Materials

    NASA Astrophysics Data System (ADS)

    Lagow, Benjamin W.

    2016-08-01

    Materials selection criteria in gas turbine engine design are reviewed, and several design challenges are introduced where selection of low coefficient of thermal expansion (CTE) materials can help improve engine performance and operability. This is followed by a review of the types of low CTE materials that are suitable for gas turbine engine applications, and discussion of their advantages and disadvantages. The primary limitation of low CTE materials is their maximum use temperature; if higher temperature materials could be developed, this could result in novel turbine system designs for gas turbine engines.

  20. Computational materials design for energy applications

    NASA Astrophysics Data System (ADS)

    Ozolins, Vidvuds

    2013-03-01

    General adoption of sustainable energy technologies depends on the discovery and development of new high-performance materials. For instance, waste heat recovery and electricity generation via the solar thermal route require bulk thermoelectrics with a high figure of merit (ZT) and thermal stability at high-temperatures. Energy recovery applications (e.g., regenerative braking) call for the development of rapidly chargeable systems for electrical energy storage, such as electrochemical supercapacitors. Similarly, use of hydrogen as vehicular fuel depends on the ability to store hydrogen at high volumetric and gravimetric densities, as well as on the ability to extract it at ambient temperatures at sufficiently rapid rates. We will discuss how first-principles computational methods based on quantum mechanics and statistical physics can drive the understanding, improvement and prediction of new energy materials. We will cover prediction and experimental verification of new earth-abundant thermoelectrics, transition metal oxides for electrochemical supercapacitors, and kinetics of mass transport in complex metal hydrides. Research has been supported by the US Department of Energy under grant Nos. DE-SC0001342, DE-SC0001054, DE-FG02-07ER46433, and DE-FC36-08GO18136.

  1. New design strategy for realizing multiferroic materials

    NASA Astrophysics Data System (ADS)

    Puggioni, Danilo; Giovannetti, Gianluca; Capone, Massimo; Rondinelli, James

    Ferroelectricity is a property that only insulating materials can exhibit. For this reason, nearly all searches for new multiferroic compounds, those simultaneously exhibiting ferroelectric and magnetic order, have focused on insulating magnetic oxides. Here, we propose a different approach: Start from a conducting oxide with broken inversion symmetry and search for routes to induce long-range magnetic order. Using density-functional and dynamical mean-field theories, we investigate the electronic properties of the polar metallic oxide LiOsO3. We show that a multiferroic state can be engineered by enclosing LiOsO3 between an insulating material, LiNbO3. We predict that the 1/1 superlattice of LiOsO3 and LiNbO3 exhibits strong coupling between magnetic and ferroelectric degrees of freedom with a ferroelectric polarization of 41.2 μCcm-2, Curie temperature of 927 K, and Néel temperature of 379 K. Our results show that one can start with polar metallic oxides to make multiferroics.

  2. Material Compatibility with Space Storable Propellants. Design Guidebook

    NASA Technical Reports Server (NTRS)

    Uney, P. E.; Fester, D. A.

    1972-01-01

    An important consideration in the design of spacecraft for interplanetary missions is the compatibility of storage materials with the propellants. Serious problems can arise because many propellants are either extremely reactive or subject to catalytic decomposition, making the selection of proper materials of construction for propellant containment and control a critical requirement for the long-life applications. To aid in selecting materials and designing and evaluating various propulsion subsystems, available information on the compatibility of spacecraft materials with propellants of interest was compiled from literature searches and personal contacts. The compatibility of both metals and nonmetals with hydrazine, monomethyl hydrazine, nitrated hydrazine, and diborance fuels and nitrogen tetroxide, fluorine, oxygen difluoride, and Flox oxidizers was surveyed. These fuels and oxidizers encompass the wide variety of problems encountered in propellant storage. As such, they present worst case situations of the propellant affecting the material and the material affecting the propellant. This includes material attack, propellant decomposition, and the formation of clogging materials.

  3. Stochastic Analysis and Design of Heterogeneous Microstructural Materials System

    NASA Astrophysics Data System (ADS)

    Xu, Hongyi

    Advanced materials system refers to new materials that are comprised of multiple traditional constituents but complex microstructure morphologies, which lead to superior properties over the conventional materials. To accelerate the development of new advanced materials system, the objective of this dissertation is to develop a computational design framework and the associated techniques for design automation of microstructure materials systems, with an emphasis on addressing the uncertainties associated with the heterogeneity of microstructural materials. Five key research tasks are identified: design representation, design evaluation, design synthesis, material informatics and uncertainty quantification. Design representation of microstructure includes statistical characterization and stochastic reconstruction. This dissertation develops a new descriptor-based methodology, which characterizes 2D microstructures using descriptors of composition, dispersion and geometry. Statistics of 3D descriptors are predicted based on 2D information to enable 2D-to-3D reconstruction. An efficient sequential reconstruction algorithm is developed to reconstruct statistically equivalent random 3D digital microstructures. In design evaluation, a stochastic decomposition and reassembly strategy is developed to deal with the high computational costs and uncertainties induced by material heterogeneity. The properties of Representative Volume Elements (RVE) are predicted by stochastically reassembling SVE elements with stochastic properties into a coarse representation of the RVE. In design synthesis, a new descriptor-based design framework is developed, which integrates computational methods of microstructure characterization and reconstruction, sensitivity analysis, Design of Experiments (DOE), metamodeling and optimization the enable parametric optimization of the microstructure for achieving the desired material properties. Material informatics is studied to efficiently reduce the

  4. Designing Educative Curriculum Materials: A Theoretically and Empirically Driven Process

    ERIC Educational Resources Information Center

    Davis, Elizabeth A.; Palincsar, Annemarie Sullivan; Arias, Anna Maria; Bismack, Amber Schultz; Marulis, Loren M.; Iwashyna, Stefanie K.

    2014-01-01

    In this article, the authors argue for a design process in the development of educative curriculum materials that is theoretically and empirically driven. Using a design-based research approach, they describe their design process for incorporating educative features intended to promote teacher learning into existing, high-quality curriculum…

  5. Cultivating Design Thinking in Students through Material Inquiry

    ERIC Educational Resources Information Center

    Renard, Helene

    2014-01-01

    Design thinking is a way of understanding and engaging with the world that has received much attention in academic and business circles in recent years. This article examines a hands-on learning model as a vehicle for developing design thinking capacity in students. An overview of design thinking grounds the discussion of the material-based…

  6. Nondestructive evaluation of composite materials - A design philosophy

    NASA Technical Reports Server (NTRS)

    Duke, J. C., Jr.; Henneke, E. G., II; Stinchcomb, W. W.; Reifsnider, K. L.

    1984-01-01

    Efficient and reliable structural design utilizing fiber reinforced composite materials may only be accomplished if the materials used may be nondestructively evaluated. There are two major reasons for this requirement: (1) composite materials are formed at the time the structure is fabricated and (2) at practical strain levels damage, changes in the condition of the material, that influence the structure's mechanical performance is present. The fundamental basis of such a nondestructive evaluation capability is presented. A discussion of means of assessing nondestructively the material condition as well as a damage mechanics theory that interprets the material condition in terms of its influence on the mechanical response, stiffness, strength and life is provided.

  7. Characterization of elastomeric materials with application to design

    NASA Technical Reports Server (NTRS)

    Bower, Mark V.

    1986-01-01

    Redesign of the Space Shuttle Solid Booster has necessitated re-evaluation of the material used in the field joint O-ring seals. The viscoelastic characteristics of five candidate materials were determined. The five materials are: two fluorocarbon compounds, two nitrile compounds, and a silicon compound. The materials were tested in a uniaxial compression test to determine the characteristic relaxation functions. These tests were performed at five different temperatures. A master material curve was developed for each material from the experimental data. The results are compared to tensile relaxation tests. Application of these results to the design analysis is discussed in detail.

  8. Design with brittle materials - An interdisciplinary educational program

    NASA Technical Reports Server (NTRS)

    Mueller, J. I.; Bollard, R. J. H.; Hartz, B. J.; Kobayashi, A. S.; Love, W. J.; Scott, W. D.; Taggart, R.; Whittemore, O. J.

    1980-01-01

    A series of interdisciplinary design courses being offered to senior and graduate engineering students at the University of Washington is described. Attention is given to the concepts and some of the details on group design projects that have been undertaken during the past two years. It is noted that ceramic materials normally demonstrate a large scatter in strength properties. As a consequence, when designing with these materials, the conventional 'mil standards' design stresses with acceptable margins of safety cannot by employed and the designer is forced to accept a probable number of failures in structures of a given brittle material. It is this prediction of the probability of failure for structures of given, well-characterized materials that forms the basis for this series of courses.

  9. Center for Intelligent Fuel Cell Materials Design

    SciTech Connect

    Santurri, P.R.,; Hartmann-Thompson, C.; Keinath, S.E.

    2008-08-26

    The goal of this work was to develop a composite proton exchange membrane utilizing 1) readily available, low cost materials 2) readily modified and 3) easily processed to meet the chemical, mechanical and electrical requirements of high temperature PEM fuel cells. One of the primary goals was to produce a conducting polymer that met the criteria for strength, binding capability for additives, chemical stability, dimensional stability and good conductivity. In addition compatible, specialty nanoparticles were synthesized to provide water management and enhanced conductivity. The combination of these components in a multilayered, composite PEM has demonstrated improved conductivity at high temperatures and low humidity over commercially available polymers. The research reported in this final document has greatly increased the knowledge base related to post sulfonation of chemically and mechanically stable engineered polymers (Radel). Both electrical and strength factors for the degree of post sulfonation far exceed previous data, indicating the potential use of these materials in suitable proton exchange membrane architectures for the development of fuel cells. In addition compatible, hydrophilic, conductive nano-structures have been synthesized and incorporated into unique proton exchange membrane architectures. The use of post sulfonation for the engineered polymer and nano-particle provide cost effective techniques to produce the required components of a proton exchange membrane. The development of a multilayer proton exchange membrane as described in our work has produced a highly stable membrane at 170°C with conductivities exceeding commercially available proton exchange membranes at high temperatures and low humidity. The components and architecture of the proton exchange membrane discussed will provide low cost components for the portable market and potentially the transportation market. The development of unique components and membrane architecture

  10. The automated design of materials far from equilibrium

    NASA Astrophysics Data System (ADS)

    Miskin, Marc Z.

    Automated design is emerging as a powerful concept in materials science. By combining computer algorithms, simulations, and experimental data, new techniques are being developed that start with high level functional requirements and identify the ideal materials that achieve them. This represents a radically different picture of how materials become functional in which technological demand drives material discovery, rather than the other way around. At the frontiers of this field, materials systems previously considered too complicated can start to be controlled and understood. Particularly promising are materials far from equilibrium. Material robustness, high strength, self-healing and memory are properties displayed by several materials systems that are intrinsically out of equilibrium. These and other properties could be revolutionary, provided they can first be controlled. This thesis conceptualizes and implements a framework for designing materials that are far from equilibrium. We show how, even in the absence of a complete physical theory, design from the top down is possible and lends itself to producing physical insight. As a prototype system, we work with granular materials: collections of athermal, macroscopic identical objects, since these materials function both as an essential component of industrial processes as well as a model system for many non-equilibrium states of matter. We show that by placing granular materials in the context of design, benefits emerge simultaneously for fundamental and applied interests. As first steps, we use our framework to design granular aggregates with extreme properties like high stiffness, and softness. We demonstrate control over nonlinear effects by producing exotic aggregates that stiffen under compression. Expanding on our framework, we conceptualize new ways of thinking about material design when automatic discovery is possible. We show how to build rules that link particle shapes to arbitrary granular packing

  11. Design guide for Type B radioactive material transportation packaging

    SciTech Connect

    Arbital, J.G.; Stumpfl, E.; Moses, S.D.

    1995-11-01

    In a joint effort between Martin Marietta Energy Systems, Inc. of Oak Ridge, Tennessee and the US Department of Energy (DOE) Albuquerque Operations (ALO), a guide to transportation package design for defense program materials has been developed (DOE, 1994). The Design Guide, as it is referred to, is a comprehensive document that uses a systems engineering approach to the design of Type B fissile packages for radioactive material handling and shipping. The specific design aspects addressed in the guide are geared toward special nuclear materials, however the guide can be used to design any transportation package for Type B unirradiated material (fissile or nonfissile). The Design Guide covers all elements of a successful design effort including structural integrity issues, thermal performance, containment systems, shielding requirements, criticality concerns, operational considerations, acceptance criteria, maintenance program, materials compatibility, and quality assurance. The Design Guide was issued in DRAFT form for comments by the DOE complex. Comments have since been incorporated. The Design Guide will be further updated as new technologies are developed, however it can be successfully applied at this time.

  12. Nano-architecture and material designs for water splitting photoelectrodes.

    PubMed

    Chen, Hao Ming; Chen, Chih Kai; Liu, Ru-Shi; Zhang, Lei; Zhang, Jiujun; Wilkinson, David P

    2012-09-01

    This review concerns the efficient conversion of sunlight into chemical fuels through the photoelectrochemical splitting of water, which has the potential to generate sustainable hydrogen fuel. In this review, we discuss various photoelectrode materials and relative design strategies with their associated fabrication for solar water splitting. Factors affecting photoelectrochemical performance of these materials and designs are also described. The most recent progress in the research and development of new materials as well as their corresponding photoelectrodes is also summarized in this review. Finally, the research strategies and future directions for water splitting are discussed with recommendations to facilitate the further exploration of new photoelectrode materials and their associated technologies.

  13. Photovoltaic module encapsulation design and materials selection, volume 1

    NASA Astrophysics Data System (ADS)

    Cuddihy, E.; Carroll, W.; Coulbert, C.; Gupta, A.; Liang, R. H.

    1982-06-01

    Encapsulation material system requirements, material selection criteria, and the status and properties of encapsulation materials and processes available are presented. Technical and economic goals established for photovoltaic modules and encapsulation systems and their status are described. Available encapsulation technology and data are presented to facilitate design and material selection for silicon flat plate photovoltaic modules, using the best materials available and processes optimized for specific power applications and geographic sites. The operational and environmental loads that encapsulation system functional requirements and candidate design concepts and materials that are identified to have the best potential to meet the cost and performance goals for the flat plate solar array project are described. Available data on encapsulant material properties, fabrication processing, and module life and durability characteristics are presented.

  14. Designing Radiation Resistance in Materials for Fusion Energy

    NASA Astrophysics Data System (ADS)

    Zinkle, S. J.; Snead, L. L.

    2014-07-01

    Proposed fusion and advanced (Generation IV) fission energy systems require high-performance materials capable of satisfactory operation up to neutron damage levels approaching 200 atomic displacements per atom with large amounts of transmutant hydrogen and helium isotopes. After a brief overview of fusion reactor concepts and radiation effects phenomena in structural and functional (nonstructural) materials, three fundamental options for designing radiation resistance are outlined: Utilize matrix phases with inherent radiation tolerance, select materials in which vacancies are immobile at the design operating temperatures, or engineer materials with high sink densities for point defect recombination. Environmental and safety considerations impose several additional restrictions on potential materials systems, but reduced-activation ferritic/martensitic steels (including thermomechanically treated and oxide dispersion-strengthened options) and silicon carbide ceramic composites emerge as robust structural materials options. Materials modeling (including computational thermodynamics) and advanced manufacturing methods are poised to exert a major impact in the next ten years.

  15. Photovoltaic module encapsulation design and materials selection, volume 1

    NASA Technical Reports Server (NTRS)

    Cuddihy, E.; Carroll, W.; Coulbert, C.; Gupta, A.; Liang, R. H.

    1982-01-01

    Encapsulation material system requirements, material selection criteria, and the status and properties of encapsulation materials and processes available are presented. Technical and economic goals established for photovoltaic modules and encapsulation systems and their status are described. Available encapsulation technology and data are presented to facilitate design and material selection for silicon flat plate photovoltaic modules, using the best materials available and processes optimized for specific power applications and geographic sites. The operational and environmental loads that encapsulation system functional requirements and candidate design concepts and materials that are identified to have the best potential to meet the cost and performance goals for the flat plate solar array project are described. Available data on encapsulant material properties, fabrication processing, and module life and durability characteristics are presented.

  16. Photovoltaic-module encapsulation design and materials selection: Volume 1

    SciTech Connect

    Cuddihy, E.; Carroll, W.; Coulbert, C.; Gupta, A.; Liang, R.

    1982-06-01

    Encapsulation-material system requirements, material-selection criteria, and the status and properties of encapsulation materials and processes available to the module manufacturer are presented in detail. Technical and economic goals established for photovoltaic modules and encapsulation systems and their status are described for material suppliers to assist them in assessing the suitability of materials in their product lines and the potential of new-material products. A comprehensive discussion of available encapsulation technology and data is presented to facilitate design and material selection for silicon flat-plate photovoltaic modules, using the best materials available and processes optimized for specific power applications and geographic sites. A basis is provided for specifying the operational and environmental loads that encapsulation material systems must resist. Potential deployment sites for which cost effectiveness may be achieved at a module price much greater than $0.70/W/sub p/, are also considered; data on higher-cost encapsulant materials and processes that may be in use and other material candidates that may be justified for special application are discussed. Described are encapsulation-system functional requirements and candidate design concepts and materials that have been identified and analyzed as having the best potential to meet the cost and performance goals for the Flat-Plate Solar Array Project. The available data on encapsulant material properties, fabrication processing, and module life and durability characteristics are presented.

  17. Design of meta-materials with novel thermoelastic properties

    NASA Astrophysics Data System (ADS)

    Watts, Seth

    The development of new techniques in micro-manufacturing in recent years has enabled the fabrication of material microstructures with essentially arbitrary designs, including those with multiple constituent materials and void space in nearly any geometry. With an essentially open design space, the onus is now on the engineer to design composite materials which are optimal for their purpose. These new materials, called meta-materials or materials with architected microstructures, offer the potential to mix and match properties in a way that exceeds that of traditional composites. We concentrate on the thermal and elastic properties of isotropic meta-materials, and design microstructures with combinations of Young's modulus, Poisson's ratio, thermal conductivity, thermal expansion, and mass density which are not found among naturally-occurring or traditional composite materials. We also produce designs with thermal expansion far below other materials. We use homogenization theory to predict the material properties of a bulk meta-material comprised of a periodic lattice of unit cells, then use topology optimization to rearrange two constituent materials and void space within the unit cell in order to extremize an objective function which yields the combinations of properties we seek. This method is quite general and can be extended to consider additional properties of interest. We constrain the design space to satisfy material isotropy directly (2D), or to satisfy cubic symmetry (3D), from which point an isotropy constraint function is easily applied. We develop and use filtering, nonlinear interpolation, and thresholding methods to render the design problem well-posed, and as a result ensure our designs are manufacturable. We have written two computer implementations of this design methodology. The first is for creating two-dimensional designs, which can run on a serial computer in approximately half an hour. The second is a parallel implementation to allow

  18. Technology update: Tethered aerostat structural design and material developments

    NASA Technical Reports Server (NTRS)

    Witherow, R. G.

    1975-01-01

    Requirements exist for an extremely stable, high performance, all-weather tethered aerostat system. This requirement has been satisfied by a 250,000 cubic foot captive buoyant vehicle as demonstrated by over a year of successful field operations. This achievement required significant advancements in several technology areas including composite materials design, aerostatics and aerodynamics, structural design, electro-mechanical design, vehicle fabrication and mooring operations. This paper specifically addresses the materials and structural design aspects of pressurized buoyant vehicles as related to the general class of Lighter Than Air vehicles.

  19. FOREWORD: Computational methodologies for designing materials Computational methodologies for designing materials

    NASA Astrophysics Data System (ADS)

    Rahman, Talat S.

    2009-02-01

    It would be fair to say that in the past few decades, theory and computer modeling have played a major role in elucidating the microscopic factors that dictate the properties of functional novel materials. Together with advances in experimental techniques, theoretical methods are becoming increasingly capable of predicting properties of materials at different length scales, thereby bringing in sight the long-sought goal of designing material properties according to need. Advances in computer technology and their availability at a reasonable cost around the world have made tit all the more urgent to disseminate what is now known about these modern computational techniques. In this special issue on computational methodologies for materials by design we have tried to solicit articles from authors whose works collectively represent the microcosm of developments in the area. This turned out to be a difficult task for a variety of reasons, not the least of which is space limitation in this special issue. Nevertheless, we gathered twenty articles that represent some of the important directions in which theory and modeling are proceeding in the general effort to capture the ability to produce materials by design. The majority of papers presented here focus on technique developments that are expected to uncover further the fundamental processes responsible for material properties, and for their growth modes and morphological evolutions. As for material properties, some of the articles here address the challenges that continue to emerge from attempts at accurate descriptions of magnetic properties, of electronically excited states, and of sparse matter, all of which demand new looks at density functional theory (DFT). I should hasten to add that much of the success in accurate computational modeling of materials emanates from the remarkable predictive power of DFT, without which we would not be able to place the subject on firm theoretical grounds. As we know and will also

  20. Exploiting the dispersion of the double-negative-index fishnet metamaterial to create a broadband low-profile metallic lens.

    PubMed

    Orazbayev, B; Pacheco-Peña, V; Beruete, M; Navarro-Cía, M

    2015-04-01

    Metamaterial lenses with close values of permittivity and permeability usually display low reflection losses at the expense of narrow single frequency operation. Here, a broadband low-profile lens is designed by exploiting the dispersion of a fishnet metamaterial together with the zoning technique. The lens operates in a broadband regime from 54 GHz to 58 GHz, representing a fractional bandwidth ~7%, and outperforms Silicon lenses between 54 and 55.5 GHz. This broadband operation is demonstrated by a systematic analysis comprising Huygens-Fresnel analytical method, full-wave numerical simulations and experimental measurements at millimeter waves. For demonstrative purposes, a detailed study of the lens operation at two frequencies is done for the most important lens parameters (focal length, depth of focus, resolution, radiation diagram). Experimental results demonstrate diffraction-limited ~0.5λ transverse resolution, in agreement with analytical and numerical calculations. In a lens antenna configuration, a directivity as high as 16.6 dBi is achieved. The different focal lengths implemented into a single lens could be potentially used for realizing the front end of a non-mechanical zoom millimeter-wave imaging system. PMID:25968693

  1. Designing high-performance layered thermoelectric materials through orbital engineering

    PubMed Central

    Zhang, Jiawei; Song, Lirong; Madsen, Georg K. H.; Fischer, Karl F. F.; Zhang, Wenqing; Shi, Xun; Iversen, Bo B.

    2016-01-01

    Thermoelectric technology, which possesses potential application in recycling industrial waste heat as energy, calls for novel high-performance materials. The systematic exploration of novel thermoelectric materials with excellent electronic transport properties is severely hindered by limited insight into the underlying bonding orbitals of atomic structures. Here we propose a simple yet successful strategy to discover and design high-performance layered thermoelectric materials through minimizing the crystal field splitting energy of orbitals to realize high orbital degeneracy. The approach naturally leads to design maps for optimizing the thermoelectric power factor through forming solid solutions and biaxial strain. Using this approach, we predict a series of potential thermoelectric candidates from layered CaAl2Si2-type Zintl compounds. Several of them contain nontoxic, low-cost and earth-abundant elements. Moreover, the approach can be extended to several other non-cubic materials, thereby substantially accelerating the screening and design of new thermoelectric materials. PMID:26948043

  2. Designing high-performance layered thermoelectric materials through orbital engineering.

    PubMed

    Zhang, Jiawei; Song, Lirong; Madsen, Georg K H; Fischer, Karl F F; Zhang, Wenqing; Shi, Xun; Iversen, Bo B

    2016-01-01

    Thermoelectric technology, which possesses potential application in recycling industrial waste heat as energy, calls for novel high-performance materials. The systematic exploration of novel thermoelectric materials with excellent electronic transport properties is severely hindered by limited insight into the underlying bonding orbitals of atomic structures. Here we propose a simple yet successful strategy to discover and design high-performance layered thermoelectric materials through minimizing the crystal field splitting energy of orbitals to realize high orbital degeneracy. The approach naturally leads to design maps for optimizing the thermoelectric power factor through forming solid solutions and biaxial strain. Using this approach, we predict a series of potential thermoelectric candidates from layered CaAl2Si2-type Zintl compounds. Several of them contain nontoxic, low-cost and earth-abundant elements. Moreover, the approach can be extended to several other non-cubic materials, thereby substantially accelerating the screening and design of new thermoelectric materials. PMID:26948043

  3. Designing high-performance layered thermoelectric materials through orbital engineering

    NASA Astrophysics Data System (ADS)

    Zhang, Jiawei; Song, Lirong; Madsen, Georg K. H.; Fischer, Karl F. F.; Zhang, Wenqing; Shi, Xun; Iversen, Bo B.

    2016-03-01

    Thermoelectric technology, which possesses potential application in recycling industrial waste heat as energy, calls for novel high-performance materials. The systematic exploration of novel thermoelectric materials with excellent electronic transport properties is severely hindered by limited insight into the underlying bonding orbitals of atomic structures. Here we propose a simple yet successful strategy to discover and design high-performance layered thermoelectric materials through minimizing the crystal field splitting energy of orbitals to realize high orbital degeneracy. The approach naturally leads to design maps for optimizing the thermoelectric power factor through forming solid solutions and biaxial strain. Using this approach, we predict a series of potential thermoelectric candidates from layered CaAl2Si2-type Zintl compounds. Several of them contain nontoxic, low-cost and earth-abundant elements. Moreover, the approach can be extended to several other non-cubic materials, thereby substantially accelerating the screening and design of new thermoelectric materials.

  4. Designing high-performance layered thermoelectric materials through orbital engineering.

    PubMed

    Zhang, Jiawei; Song, Lirong; Madsen, Georg K H; Fischer, Karl F F; Zhang, Wenqing; Shi, Xun; Iversen, Bo B

    2016-03-07

    Thermoelectric technology, which possesses potential application in recycling industrial waste heat as energy, calls for novel high-performance materials. The systematic exploration of novel thermoelectric materials with excellent electronic transport properties is severely hindered by limited insight into the underlying bonding orbitals of atomic structures. Here we propose a simple yet successful strategy to discover and design high-performance layered thermoelectric materials through minimizing the crystal field splitting energy of orbitals to realize high orbital degeneracy. The approach naturally leads to design maps for optimizing the thermoelectric power factor through forming solid solutions and biaxial strain. Using this approach, we predict a series of potential thermoelectric candidates from layered CaAl2Si2-type Zintl compounds. Several of them contain nontoxic, low-cost and earth-abundant elements. Moreover, the approach can be extended to several other non-cubic materials, thereby substantially accelerating the screening and design of new thermoelectric materials.

  5. Evaluation of materials and design modifications for aircraft brakes

    NASA Technical Reports Server (NTRS)

    Ho, T. L.; Kennedy, F. E.; Peterson, M. B.

    1975-01-01

    A test program is described which was carried out to evaluate several proposed design modifications and several high-temperature friction materials for use in aircraft disk brakes. The evaluation program was carried out on a specially built test apparatus utilizing a disk brake and wheel half from a small het aircraft. The apparatus enabled control of brake pressure, velocity, and braking time. Tests were run under both constant and variable velocity conditions and covered a kinetic energy range similar to that encountered in aircraft brake service. The results of the design evaluation program showed that some improvement in brake performance can be realized by making design changes in the components of the brake containing friction material. The materials evaluation showed that two friction materials show potential for use in aircraft disk brakes. One of the materials is a nickel-based sintered composite, while the other is a molybdenum-based material. Both materials show much lower wear rates than conventional copper-based materials and are better able to withstand the high temperatures encountered during braking. Additional materials improvement is necessary since both materials show a significant negative slope of the friction-velocity curve at low velocities.

  6. Current Materials on Barrier-Free Design. Revised.

    ERIC Educational Resources Information Center

    National Easter Seal Society for Crippled Children and Adults, Chicago, IL.

    An eight-page annotated bibliography contains material available from the National Easter Seal Society and current material available from other sources. The annotations are grouped under design, guides, planning resources, standards/legislation, and general. Ordering information is provided. (MLF)

  7. Sculpture: Creative Designs with Modern Materials (Tentative Course Outline).

    ERIC Educational Resources Information Center

    Dubocq, Edward R.

    This document reports on a course in comprehension and application of various techniques of sculpture and collage, using a contemporary point of view. Students will work with contemporary materials such as wood, metals, plaster, plastics, styrofoam, and many other cardboard basic materials suitable for creative design products. This unit will…

  8. Design Guidelines for Digital Learning Material for Food Chemistry Education.

    ERIC Educational Resources Information Center

    Diederen, Julia; Gruppen, Harry; Voragen, Alphons G. J.; Hartog, Rob; Mulder, Martin; Biemans, Harm

    This paper describes the first stage of a 4-year research project on the design, development and use of Web-based digital learning material for food chemistry education. The paper discusses design guidelines, based on principles that were selected from theories on learning and instruction, and illustrates in detail how these guidelines were used…

  9. Rational design of inorganic dielectric materials with expected permittivity

    NASA Astrophysics Data System (ADS)

    Xie, Congwei; Oganov, Artem R.; Dong, Dong; Liu, Ning; Li, Duan; Debela, Tekalign Terfa

    2015-11-01

    Techniques for rapid design of dielectric materials with appropriate permittivity for many important technological applications are urgently needed. It is found that functional structure blocks (FSBs) are helpful in rational design of inorganic dielectrics with expected permittivity. To achieve this, coordination polyhedra are parameterized as FSBs and a simple empirical model to evaluate permittivity based on these FSB parameters is proposed. Using this model, a wide range of examples including ferroelectric, high/low permittivity materials are discussed, resulting in several candidate materials for experimental follow-up.

  10. Rational design of inorganic dielectric materials with expected permittivity

    PubMed Central

    Xie, Congwei; Oganov, Artem R.; Dong, Dong; Liu, Ning; Li, Duan; Debela, Tekalign Terfa

    2015-01-01

    Techniques for rapid design of dielectric materials with appropriate permittivity for many important technological applications are urgently needed. It is found that functional structure blocks (FSBs) are helpful in rational design of inorganic dielectrics with expected permittivity. To achieve this, coordination polyhedra are parameterized as FSBs and a simple empirical model to evaluate permittivity based on these FSB parameters is proposed. Using this model, a wide range of examples including ferroelectric, high/low permittivity materials are discussed, resulting in several candidate materials for experimental follow-up. PMID:26617342

  11. Rational design of inorganic dielectric materials with expected permittivity.

    PubMed

    Xie, Congwei; Oganov, Artem R; Dong, Dong; Liu, Ning; Li, Duan; Debela, Tekalign Terfa

    2015-11-30

    Techniques for rapid design of dielectric materials with appropriate permittivity for many important technological applications are urgently needed. It is found that functional structure blocks (FSBs) are helpful in rational design of inorganic dielectrics with expected permittivity. To achieve this, coordination polyhedra are parameterized as FSBs and a simple empirical model to evaluate permittivity based on these FSB parameters is proposed. Using this model, a wide range of examples including ferroelectric, high/low permittivity materials are discussed, resulting in several candidate materials for experimental follow-up.

  12. Structure-Based Design of Functional Amyloid Materials

    DOE PAGESBeta

    Li, Dan; Jones, Eric M.; Sawaya, Michael R.; Furukawa, Hiroyasu; Luo, Fang; Ivanova, Magdalena; Sievers, Stuart A.; Wang, Wenyuan; Yaghi, Omar M.; Liu, Cong; et al

    2014-12-04

    We report that amyloid fibers, once exclusively associated with disease, are acquiring utility as a class of biological nanomaterials. We introduce a method that utilizes the atomic structures of amyloid peptides, to design materials with versatile applications. As a model application, we designed amyloid fibers capable of capturing carbon dioxide from flue gas, to address the global problem of excess anthropogenic carbon dioxide. By measuring dynamic separation of carbon dioxide from nitrogen, we show that fibers with designed amino acid sequences double the carbon dioxide binding capacity of the previously reported fiber formed by VQIVYK from Tau protein. In amore » second application, we designed fibers that facilitate retroviral gene transfer. Finally, by measuring lentiviral transduction, we show that designed fibers exceed the efficiency of polybrene, a commonly used enhancer of transduction. The same procedures can be adapted to the design of countless other amyloid materials with a variety of properties and uses.« less

  13. Structure-Based Design of Functional Amyloid Materials

    SciTech Connect

    Li, Dan; Jones, Eric M.; Sawaya, Michael R.; Furukawa, Hiroyasu; Luo, Fang; Ivanova, Magdalena; Sievers, Stuart A.; Wang, Wenyuan; Yaghi, Omar M.; Liu, Cong; Eisenberg, David S.

    2014-12-04

    We report that amyloid fibers, once exclusively associated with disease, are acquiring utility as a class of biological nanomaterials. We introduce a method that utilizes the atomic structures of amyloid peptides, to design materials with versatile applications. As a model application, we designed amyloid fibers capable of capturing carbon dioxide from flue gas, to address the global problem of excess anthropogenic carbon dioxide. By measuring dynamic separation of carbon dioxide from nitrogen, we show that fibers with designed amino acid sequences double the carbon dioxide binding capacity of the previously reported fiber formed by VQIVYK from Tau protein. In a second application, we designed fibers that facilitate retroviral gene transfer. Finally, by measuring lentiviral transduction, we show that designed fibers exceed the efficiency of polybrene, a commonly used enhancer of transduction. The same procedures can be adapted to the design of countless other amyloid materials with a variety of properties and uses.

  14. Evolution of heavy duty engine valves - materials and design

    SciTech Connect

    Schaefer, S.K.; Larson, J.M.; Jenkins, L.F.; Wang, Y.

    1997-12-31

    Engine poppet valves control gas flow in internal combustion engines. The combustion event and the flow of the gases formed past the valve during the intake or exhaust portion of the combustion cycle, expose heavy duty diesel valves to high temperatures, oxidizing or corroding atmospheres and high stresses from firing and seating. This paper is a review of heavy duty diesel engine valve material and design evolution over the last fifty years in North America. The primary driving forces behind the evolution have historically been the need for improved durability and more cost effective designs. However, in recent years engine emission regulatory requirements have become an equally important influence on valve material selection and design. The paper also endeavors to predict how heavy duty diesel engine valve materials and designs may change in response to these driving forces in the foreseeable future.

  15. Materials and design of the European DEMO blankets

    NASA Astrophysics Data System (ADS)

    Boccaccini, L. V.; Giancarli, L.; Janeschitz, G.; Hermsmeyer, S.; Poitevin, Y.; Cardella, A.; Diegele, E.

    2004-08-01

    The Helium Cooled Lithium Lead (HCLL) and the Helium Cooled Pebble Bed (HCPB) Blanket are the reference concepts in the European Breeding Blanket Programme for the DEMO design and for the related long term R&D. Recently, a similar design for both concepts has been developed, in particular both concepts use helium coolant and RAFM steel EUROFER as structural material. In this paper the interactions between the selected materials and the proposed DEMO designs are discussed. In particular the design features related to the tritium production, power extraction, material compatibility and fabrication processes are addressed. All these features contribute to the definition of DEMO concepts which are attractive for a future fusion power plant in terms of safety, availability and economics.

  16. Microstructural design of cellular materials I: Honeycomb beams and plates

    SciTech Connect

    Huang, J.S.; Gibson, L.J.

    1992-06-01

    Performance indices for materials describe the mechanical efficiency of a component under a given mode of loading: The higher the performance index, the lower the mass of the component for a given mechanical requirement. Material selection charts (Ashby, 1989) offer a graphical means of comparing performance indices for a wide range of materials. Performance indices are described. Micromechanical models for behaviour of cellular materials are used to suggest novel microstructural designs for cellular materials with improved performance. Three novel microstructural designs, described in companion papers, have been fabricated and tested. Results of the tests indicate that the new microstructures have higher values of some performance indices than those of the solids from which they are made.

  17. Structural and Machine Design Using Piezoceramic Materials: A Guide for Structural Design Engineers

    NASA Technical Reports Server (NTRS)

    Inman, Daniel J.; Cudney, Harley H.

    2000-01-01

    Using piezoceramic materials is one way the design engineer can create structures which have an ability to both sense and respond to their environment. Piezoceramic materials can be used to create structural sensors and structural actuators. Because piezoceramic materials have transduction as a material property, their sensing or actuation functions are a result of what happens to the material. This is different than discrete devices we might attach to the structure. For example, attaching an accelerometer to a structure will yield an electrical signal proportional to the acceleration at the attachment point on the structure. Using a electromagnetic shaker as an actuator will create an applied force at the attachment point. Active material elements in a structural design are not easily modeled as providing transduction at a point, but rather they change the physics of the structure in the areas where they are used. Hence, a designer must not think of adding discrete devices to a structure to obtain an effect, but rather must design a structural system which accounts for the physical principles of all the elements in the structure. The purpose of this manual is to provide practicing engineers the information necessary to incorporate piezoelectric materials in structural design and machine design. First, we will review the solid-state physics of piezoelectric materials. Then we will discuss the physical characteristics of the electrical-active material-structural system. We will present the elements of this system which must be considered as part of the design task for a structural engineer. We will cover simple modeling techniques and review the features and capabilities of commercial design tools that are available. We will then cover practical how-to elements of working with piezoceramic materials. We will review sources of piezoceramic materials and built-up devices, and their characteristics. Finally, we will provide two design examples using piezoceramic

  18. Optimal shielding design for minimum materials cost or mass

    DOE PAGESBeta

    Woolley, Robert D.

    2015-12-02

    The mathematical underpinnings of cost optimal radiation shielding designs based on an extension of optimal control theory are presented, a heuristic algorithm to iteratively solve the resulting optimal design equations is suggested, and computational results for a simple test case are discussed. A typical radiation shielding design problem can have infinitely many solutions, all satisfying the problem's specified set of radiation attenuation requirements. Each such design has its own total materials cost. For a design to be optimal, no admissible change in its deployment of shielding materials can result in a lower cost. This applies in particular to very smallmore » changes, which can be restated using the calculus of variations as the Euler-Lagrange equations. Furthermore, the associated Hamiltonian function and application of Pontryagin's theorem lead to conditions for a shield to be optimal.« less

  19. Optimal shielding design for minimum materials cost or mass

    SciTech Connect

    Woolley, Robert D.

    2015-12-02

    The mathematical underpinnings of cost optimal radiation shielding designs based on an extension of optimal control theory are presented, a heuristic algorithm to iteratively solve the resulting optimal design equations is suggested, and computational results for a simple test case are discussed. A typical radiation shielding design problem can have infinitely many solutions, all satisfying the problem's specified set of radiation attenuation requirements. Each such design has its own total materials cost. For a design to be optimal, no admissible change in its deployment of shielding materials can result in a lower cost. This applies in particular to very small changes, which can be restated using the calculus of variations as the Euler-Lagrange equations. Furthermore, the associated Hamiltonian function and application of Pontryagin's theorem lead to conditions for a shield to be optimal.

  20. Perspective: Role of structure prediction in materials discovery and design

    NASA Astrophysics Data System (ADS)

    Needs, Richard J.; Pickard, Chris J.

    2016-05-01

    Materials informatics owes much to bioinformatics and the Materials Genome Initiative has been inspired by the Human Genome Project. But there is more to bioinformatics than genomes, and the same is true for materials informatics. Here we describe the rapidly expanding role of searching for structures of materials using first-principles electronic-structure methods. Structure searching has played an important part in unraveling structures of dense hydrogen and in identifying the record-high-temperature superconducting component in hydrogen sulfide at high pressures. We suggest that first-principles structure searching has already demonstrated its ability to determine structures of a wide range of materials and that it will play a central and increasing part in materials discovery and design.

  1. Conceptual Design Report for the Irradiated Materials Characterization Laboratory (IMCL)

    SciTech Connect

    Stephanie Austad

    2010-06-01

    This document describes the design at a conceptual level for the Irradiated Materials Characterization Laboratory (IMCL) to be located at the Materials and Fuels Complex (MFC) at the Idaho National Laboratory (INL). The IMCL is an 11,000-ft2, Hazard Category-2 nuclear facility that is designed for use as a state of the-art nuclear facility for the purpose of hands-on and remote handling, characterization, and examination of irradiated and nonirradiated nuclear material samples. The IMCL will accommodate a series of future, modular, and reconfigurable instrument enclosures or caves. To provide a bounding design basis envelope for the facility-provided space and infrastructure, an instrument enclosure or cave configuration was developed and is described in some detail. However, the future instrument enclosures may be modular, integral with the instrument, or reconfigurable to enable various characterization environments to be configured as changes in demand occur. They are not provided as part of the facility.

  2. Optimal Experiment Design for Thermal Characterization of Functionally Graded Materials

    NASA Technical Reports Server (NTRS)

    Cole, Kevin D.

    2003-01-01

    The purpose of the project was to investigate methods to accurately verify that designed , materials meet thermal specifications. The project involved heat transfer calculations and optimization studies, and no laboratory experiments were performed. One part of the research involved study of materials in which conduction heat transfer predominates. Results include techniques to choose among several experimental designs, and protocols for determining the optimum experimental conditions for determination of thermal properties. Metal foam materials were also studied in which both conduction and radiation heat transfer are present. Results of this work include procedures to optimize the design of experiments to accurately measure both conductive and radiative thermal properties. Detailed results in the form of three journal papers have been appended to this report.

  3. Revisiting the Balazs thought experiment in the case of a left-handed material: electromagnetic-pulse-induced displacement of a dispersive, dissipative negative-index slab.

    PubMed

    Chau, Kenneth J; Lezec, Henri J

    2012-04-23

    We propose a set of postulates to describe the mechanical interaction between a plane-wave electromagnetic pulse and a dispersive, dissipative slab having a refractive index of arbitrary sign. The postulates include the Abraham electromagnetic momentum density, a generalized Lorentz force law, and a model for absorption-driven mass transfer from the pulse to the medium. These opto-mechanical mechanisms are incorporated into a one-dimensional finite-difference time-domain algorithm that solves Maxwell's equations and calculates the instantaneous force densities exerted by the pulse onto the slab, the momentum-per-unit-area of the pulse and slab, and the trajectories of the slab and system center-of-mass. We show that the postulates are consistent with conservation of global energy, momentum, and center-of-mass velocity at all times, even for cases in which the refractive index of the slab is negative or zero. Consistency between the set of postulates and well-established conservation laws reinforces the Abraham momentum density as the one true electromagnetic momentum density and enables, for the first time, identification of the correct form of the electromagnetic mass density distribution and development of an explicit model for mass transfer due to absorption, for the most general case of a ponderable medium that is both dispersive and dissipative.

  4. Segmented molecular design of self-healing proteinaceous materials

    PubMed Central

    Sariola, Veikko; Pena-Francesch, Abdon; Jung, Huihun; Çetinkaya, Murat; Pacheco, Carlos; Sitti, Metin; Demirel, Melik C.

    2015-01-01

    Hierarchical assembly of self-healing adhesive proteins creates strong and robust structural and interfacial materials, but understanding of the molecular design and structure–property relationships of structural proteins remains unclear. Elucidating this relationship would allow rational design of next generation genetically engineered self-healing structural proteins. Here we report a general self-healing and -assembly strategy based on a multiphase recombinant protein based material. Segmented structure of the protein shows soft glycine- and tyrosine-rich segments with self-healing capability and hard beta-sheet segments. The soft segments are strongly plasticized by water, lowering the self-healing temperature close to body temperature. The hard segments self-assemble into nanoconfined domains to reinforce the material. The healing strength scales sublinearly with contact time, which associates with diffusion and wetting of autohesion. The finding suggests that recombinant structural proteins from heterologous expression have potential as strong and repairable engineering materials. PMID:26323335

  5. Soft computing in design and manufacturing of advanced materials

    NASA Technical Reports Server (NTRS)

    Cios, Krzysztof J.; Baaklini, George Y; Vary, Alex

    1993-01-01

    The potential of fuzzy sets and neural networks, often referred to as soft computing, for aiding in all aspects of manufacturing of advanced materials like ceramics is addressed. In design and manufacturing of advanced materials, it is desirable to find which of the many processing variables contribute most to the desired properties of the material. There is also interest in real time quality control of parameters that govern material properties during processing stages. The concepts of fuzzy sets and neural networks are briefly introduced and it is shown how they can be used in the design and manufacturing processes. These two computational methods are alternatives to other methods such as the Taguchi method. The two methods are demonstrated by using data collected at NASA Lewis Research Center. Future research directions are also discussed.

  6. Segmented molecular design of self-healing proteinaceous materials

    NASA Astrophysics Data System (ADS)

    Sariola, Veikko; Pena-Francesch, Abdon; Jung, Huihun; Çetinkaya, Murat; Pacheco, Carlos; Sitti, Metin; Demirel, Melik C.

    2015-09-01

    Hierarchical assembly of self-healing adhesive proteins creates strong and robust structural and interfacial materials, but understanding of the molecular design and structure-property relationships of structural proteins remains unclear. Elucidating this relationship would allow rational design of next generation genetically engineered self-healing structural proteins. Here we report a general self-healing and -assembly strategy based on a multiphase recombinant protein based material. Segmented structure of the protein shows soft glycine- and tyrosine-rich segments with self-healing capability and hard beta-sheet segments. The soft segments are strongly plasticized by water, lowering the self-healing temperature close to body temperature. The hard segments self-assemble into nanoconfined domains to reinforce the material. The healing strength scales sublinearly with contact time, which associates with diffusion and wetting of autohesion. The finding suggests that recombinant structural proteins from heterologous expression have potential as strong and repairable engineering materials.

  7. Segmented molecular design of self-healing proteinaceous materials.

    PubMed

    Sariola, Veikko; Pena-Francesch, Abdon; Jung, Huihun; Çetinkaya, Murat; Pacheco, Carlos; Sitti, Metin; Demirel, Melik C

    2015-09-01

    Hierarchical assembly of self-healing adhesive proteins creates strong and robust structural and interfacial materials, but understanding of the molecular design and structure-property relationships of structural proteins remains unclear. Elucidating this relationship would allow rational design of next generation genetically engineered self-healing structural proteins. Here we report a general self-healing and -assembly strategy based on a multiphase recombinant protein based material. Segmented structure of the protein shows soft glycine- and tyrosine-rich segments with self-healing capability and hard beta-sheet segments. The soft segments are strongly plasticized by water, lowering the self-healing temperature close to body temperature. The hard segments self-assemble into nanoconfined domains to reinforce the material. The healing strength scales sublinearly with contact time, which associates with diffusion and wetting of autohesion. The finding suggests that recombinant structural proteins from heterologous expression have potential as strong and repairable engineering materials.

  8. High-throughput theoretical design of lithium battery materials

    NASA Astrophysics Data System (ADS)

    Shi-Gang, Ling; Jian, Gao; Rui-Juan, Xiao; Li-Quan, Chen

    2016-01-01

    The rapid evolution of high-throughput theoretical design schemes to discover new lithium battery materials is reviewed, including high-capacity cathodes, low-strain cathodes, anodes, solid state electrolytes, and electrolyte additives. With the development of efficient theoretical methods and inexpensive computers, high-throughput theoretical calculations have played an increasingly important role in the discovery of new materials. With the help of automatic simulation flow, many types of materials can be screened, optimized and designed from a structural database according to specific search criteria. In advanced cell technology, new materials for next generation lithium batteries are of great significance to achieve performance, and some representative criteria are: higher energy density, better safety, and faster charge/discharge speed. Project supported by the National Natural Science Foundation of China (Grant Nos. 11234013 and 51172274) and the National High Technology Research and Development Program of China (Grant No. 2015AA034201).

  9. Concurrent materials and process selection in conceptual design

    SciTech Connect

    Kleban, Stephen D.; Knorovsky, Gerald A.

    2000-08-16

    A method for concurrent selection of materials and a joining process based on product requirements using a knowledge-based, constraint satisfaction approach facilitates the product design and manufacturing process. Using a Windows-based computer video display and a data base of materials and their properties, the designer can ascertain the preferred composition of two parts based on various operating/environmental constraints such as load, temperature, lifetime, etc. Optimum joinder of the two parts may simultaneously be determined using a joining process data base based upon the selected composition of the components as well as the operating/environmental constraints.

  10. Optimum weight design of functionally graded material gears

    NASA Astrophysics Data System (ADS)

    Jing, Shikai; Zhang, He; Zhou, Jingtao; Song, Guohua

    2015-11-01

    Traditional gear weight optimization methods consider gear tooth number, module, face width or other dimension parameters of gear as design variables. However, due to the complicated form and geometric features peculiar to the gear, there will be large amounts of design parameters in gear design, and the influences of gear parameters changing on gear trains, transmission system and the whole equipment have to be taken into account, which increases the complexity of optimization problem. This paper puts forward to apply functionally graded materials (FGMs) to gears and then conduct the optimization. According to the force situation of gears, the material distribution form of FGM gears is determined. Then based on the performance parameters analysis of FGMs and the practical working demands for gears, a multi-objective optimization model is formed. Finally by using the goal driven optimization (GDO) method, the optimal material distribution is achieved, which makes gear weight and the maximum deformation be minimum and the maximum bending stress do not exceed the allowable stress. As an example, the applying of FGM to automotive transmission gear is conducted to illustrate the optimization design process and the result shows that under the condition of keeping the normal working performance of gear, the method achieves in greatly reducing the gear weight. This research proposes a FGM gears design method that is able to largely reduce the weight of gears by optimizing the microscopic material parameters instead of changing the macroscopic dimension parameters of gears, which reduces the complexity of gear weight optimization problem.

  11. LUTE primary mirror materials and design study report

    NASA Technical Reports Server (NTRS)

    Ruthven, Greg

    1993-01-01

    The major objective of the Lunar Ultraviolet Telescope Experiment (LUTE) Primary Mirror Materials and Design Study is to investigate the feasibility of the LUTE telescope primary mirror. A systematic approach to accomplish this key goal was taken by first understanding the optical, thermal, and structural requirements and then deriving the critical primary mirror-level requirements for ground testing, launch, and lunar operations. After summarizing the results in those requirements which drove the selection of material and the design for the primary mirror are discussed. Most important of these are the optical design which was assumed to be the MSFC baseline (i.e. 3 mirror optical system), telescope wavefront error (WFE) allocations, the telescope weight budget, and the LUTE operational temperature ranges. Mechanical load levels, reflectance and microroughness issues, and options for the LUTE metering structure were discussed and an outline for the LUTE telescope sub-system design specification was initiated. The primary mirror analysis and results are presented. The six material substrate candidates are discussed and four distinct mirror geometries which are considered are shown. With these materials and configurations together with varying the location of the mirror support points, a total of 42 possible primary mirror designs resulted. The polishability of each substrate candidate was investigated and a usage history of 0.5 meter and larger precision cryogenic mirrors (the operational low end LUTE temperature of 60 K is the reason we feel a survey of cryogenic mirrors is appropriate) that were flown or tested are presented.

  12. LUTE primary mirror materials and design study report

    NASA Astrophysics Data System (ADS)

    Ruthven, Greg

    1993-02-01

    The major objective of the Lunar Ultraviolet Telescope Experiment (LUTE) Primary Mirror Materials and Design Study is to investigate the feasibility of the LUTE telescope primary mirror. A systematic approach to accomplish this key goal was taken by first understanding the optical, thermal, and structural requirements and then deriving the critical primary mirror-level requirements for ground testing, launch, and lunar operations. After summarizing the results in those requirements which drove the selection of material and the design for the primary mirror are discussed. Most important of these are the optical design which was assumed to be the MSFC baseline (i.e. 3 mirror optical system), telescope wavefront error (WFE) allocations, the telescope weight budget, and the LUTE operational temperature ranges. Mechanical load levels, reflectance and microroughness issues, and options for the LUTE metering structure were discussed and an outline for the LUTE telescope sub-system design specification was initiated. The primary mirror analysis and results are presented. The six material substrate candidates are discussed and four distinct mirror geometries which are considered are shown. With these materials and configurations together with varying the location of the mirror support points, a total of 42 possible primary mirror designs resulted. The polishability of each substrate candidate was investigated and a usage history of 0.5 meter and larger precision cryogenic mirrors (the operational low end LUTE temperature of 60 K is the reason we feel a survey of cryogenic mirrors is appropriate) that were flown or tested are presented.

  13. [The system of designation of surgical suture materials].

    PubMed

    Adamian, A A; Vinokurova, T I; Novikova, O A; Gavriliuk, N N; Sergeev, V P

    1990-12-01

    The authors suggest a unified system of designation of type--sizes of surgical suture materials of various nature and structure, which removes the existing discrepancy between the numbering of foreign and Soviet threads as well as of Soviet threads produced by different enterprises of the country. Introduction of the new system of metric sizes of the suture threads will allow surgeons to be properly orientated in the choice of the necessary suture material and make easier the work of services engaged in the development and realization of surgical suture materials. PMID:2079825

  14. Accelerating the design of biomimetic materials by integrating RNA-seq with proteomics and materials science.

    PubMed

    Guerette, Paul A; Hoon, Shawn; Seow, Yiqi; Raida, Manfred; Masic, Admir; Wong, Fong T; Ho, Vincent H B; Kong, Kiat Whye; Demirel, Melik C; Pena-Francesch, Abdon; Amini, Shahrouz; Tay, Gavin Z; Ding, Dawei; Miserez, Ali

    2013-10-01

    Efforts to engineer new materials inspired by biological structures are hampered by the lack of genomic data from many model organisms studied in biomimetic research. Here we show that biomimetic engineering can be accelerated by integrating high-throughput RNA-seq with proteomics and advanced materials characterization. This approach can be applied to a broad range of systems, as we illustrate by investigating diverse high-performance biological materials involved in embryo protection, adhesion and predation. In one example, we rapidly engineer recombinant squid sucker ring teeth proteins into a range of structural and functional materials, including nanopatterned surfaces and photo-cross-linked films that exceed the mechanical properties of most natural and synthetic polymers. Integrating RNA-seq with proteomics and materials science facilitates the molecular characterization of natural materials and the effective translation of their molecular designs into a wide range of bio-inspired materials. PMID:24013196

  15. Turning statistical physics models into materials design engines.

    PubMed

    Miskin, Marc Z; Khaira, Gurdaman; de Pablo, Juan J; Jaeger, Heinrich M

    2016-01-01

    Despite the success statistical physics has enjoyed at predicting the properties of materials for given parameters, the inverse problem, identifying which material parameters produce given, desired properties, is only beginning to be addressed. Recently, several methods have emerged across disciplines that draw upon optimization and simulation to create computer programs that tailor material responses to specified behaviors. However, so far the methods developed either involve black-box techniques, in which the optimizer operates without explicit knowledge of the material's configuration space, or require carefully tuned algorithms with applicability limited to a narrow subclass of materials. Here we introduce a formalism that can generate optimizers automatically by extending statistical mechanics into the realm of design. The strength of this approach lies in its capability to transform statistical models that describe materials into optimizers to tailor them. By comparing against standard black-box optimization methods, we demonstrate how optimizers generated by this formalism can be faster and more effective, while remaining straightforward to implement. The scope of our approach includes possibilities for solving a variety of complex optimization and design problems concerning materials both in and out of equilibrium.

  16. The Cam Shell: An Innovative Design With Materials and Manufacturing

    NASA Technical Reports Server (NTRS)

    Chung, W. Richard; Larsen, Frank M.; Kornienko, Rob

    2003-01-01

    Most of the personal audio and video recording devices currently sold on the open market all require hands to operate. Little consideration was given to designing a hands-free unit. Such a system once designed and made available to the public could greatly benefit mobile police officers, bicyclists, adventurers, street and dirt motorcyclists, horseback riders and many others. With a few design changes water sports and skiing activities could be another large area of application. The cam shell is an innovative design in which an audio and video recording device (such as palm camcorder) is housed in a body-mounted protection system. This system is based on the concept of viewing and recording at the same time. A view cam is attached to a helmet wired to a recording unit encased in a transparent body-mounted protection system. The helmet can also be controlled by remote. The operator will have full control in recording everything. However, the recording unit will be operated completely hands-free. This project will address the design considerations and their effects on material selection and manufacturing. It will enhance the understanding of the structure of materials, and how the structure affects the behavior of the material, and the role that processing play in linking the relationship between structure and properties. A systematic approach to design feasibility study, cost analysis and problem solving will also be discussed.

  17. Material considerations in the STEREO solar array design

    NASA Astrophysics Data System (ADS)

    Tanzman, Jennifer R.

    2008-12-01

    Solar TErrestrial RElations Observatory (STEREO), the third mission in NASA's Solar Terrestrial Probes program, launched aboard a single Delta II 7925 launch vehicle on October 25, 2006 from Cape Canaveral. This two-year mission employs two nearly-identical, space-based observatories, one ahead of the Earth in its orbit, and the other trailing behind, to provide the first stereoscopic measurements of the sun and its coronal mass ejections, or CMEs. The STEREO observatories utilize four sets of solar arrays, each of which experienced a two-stage deployment on-orbit. This paper illustrates material considerations in the solar array subsystem design. It first focuses on the solar array substrate, considering material coefficient of thermal expansion (CTE) concerns when choosing a substrate laminate to which the solar cells will adhere. It then explores a similar issue when choosing a substrate insert material. Next, the focus shifts to material considerations in the solar array hinge design. This design was driven not just by function, but by a host of different material considerations, ranging from mass savings to fabrication time and cost.

  18. Structural Design Elements in Biological Materials: Application to Bioinspiration.

    PubMed

    Naleway, Steven E; Porter, Michael M; McKittrick, Joanna; Meyers, Marc A

    2015-10-01

    Eight structural elements in biological materials are identified as the most common amongst a variety of animal taxa. These are proposed as a new paradigm in the field of biological materials science as they can serve as a toolbox for rationalizing the complex mechanical behavior of structural biological materials and for systematizing the development of bioinspired designs for structural applications. They are employed to improve the mechanical properties, namely strength, wear resistance, stiffness, flexibility, fracture toughness, and energy absorption of different biological materials for a variety of functions (e.g., body support, joint movement, impact protection, weight reduction). The structural elements identified are: fibrous, helical, gradient, layered, tubular, cellular, suture, and overlapping. For each of the structural design elements, critical design parameters are presented along with constitutive equations with a focus on mechanical properties. Additionally, example organisms from varying biological classes are presented for each case to display the wide variety of environments where each of these elements is present. Examples of current bioinspired materials are also introduced for each element.

  19. Designing ICT Training Material for Chinese Language Arts Teachers.

    ERIC Educational Resources Information Center

    Lin, Janet Mei-Chuen; Wu, Cheng-Chih; Chen, Hsiu-Yen

    The purpose of this research is to tailor the design of information and communications technology (ICT) training material to the needs of Chinese language arts teachers such that the training they receive will be conducive to effective integration of ICT into instruction. Eighteen experienced teachers participated in a Delphi-like survey that…

  20. Designing ECM-mimetic Materials Using Protein Engineering

    PubMed Central

    Cai, Lei; Heilshorn, Sarah C.

    2014-01-01

    The natural extracellular matrix (ECM), with its multitude of evolved cell-instructive and cell-responsive properties, provides inspiration and guidelines for the design of engineered biomaterials. One strategy to create ECM-mimetic materials is the modular design of protein-based engineered ECM (eECM) scaffolds. This modular design strategy involves combining multiple protein domains with different functionalities into a single, modular polymer sequence, resulting in a multifunctional matrix with independent tunability of the individual domain functions. These eECMs often enable decoupled control over multiple material properties for fundamental studies of cell-matrix interactions. In addition, since the eECMs are frequently composed entirely of bioresorbable amino acids, these matrices have immense clinical potential for a variety of regenerative medicine applications. This brief review demonstrates how fundamental knowledge gained from structure-function studies of native proteins can be exploited in the design of novel protein-engineered biomaterials. While the field of protein-engineered biomaterials has existed for over 20 years, the community is only now beginning to fully explore the diversity of functional peptide modules that can be incorporated into these materials. We have chosen to highlight recent examples that either (1) demonstrate exemplary use as matrices with cell-instructive and cell-responsive properties or (2) demonstrate outstanding creativity in terms of novel molecular-level design and macro-level functionality. PMID:24365704

  1. Turning statistical physics models into materials design engines

    PubMed Central

    Miskin, Marc Z.; Khaira, Gurdaman; de Pablo, Juan J.; Jaeger, Heinrich M.

    2016-01-01

    Despite the success statistical physics has enjoyed at predicting the properties of materials for given parameters, the inverse problem, identifying which material parameters produce given, desired properties, is only beginning to be addressed. Recently, several methods have emerged across disciplines that draw upon optimization and simulation to create computer programs that tailor material responses to specified behaviors. However, so far the methods developed either involve black-box techniques, in which the optimizer operates without explicit knowledge of the material’s configuration space, or require carefully tuned algorithms with applicability limited to a narrow subclass of materials. Here we introduce a formalism that can generate optimizers automatically by extending statistical mechanics into the realm of design. The strength of this approach lies in its capability to transform statistical models that describe materials into optimizers to tailor them. By comparing against standard black-box optimization methods, we demonstrate how optimizers generated by this formalism can be faster and more effective, while remaining straightforward to implement. The scope of our approach includes possibilities for solving a variety of complex optimization and design problems concerning materials both in and out of equilibrium. PMID:26684770

  2. Neural-network-biased genetic algorithms for materials design

    NASA Astrophysics Data System (ADS)

    Patra, Tarak; Meenakshisundaram, Venkatesh; Simmons, David

    Machine learning tools have been progressively adopted by the materials science community to accelerate design of materials with targeted properties. However, in the search for new materials exhibiting properties and performance beyond that previously achieved, machine learning approaches are frequently limited by two major shortcomings. First, they are intrinsically interpolative. They are therefore better suited to the optimization of properties within the known range of accessible behavior than to the discovery of new materials with extremal behavior. Second, they require the availability of large datasets, which in some fields are not available and would be prohibitively expensive to produce. Here we describe a new strategy for combining genetic algorithms, neural networks and other machine learning tools, and molecular simulation to discover materials with extremal properties in the absence of pre-existing data. Predictions from progressively constructed machine learning tools are employed to bias the evolution of a genetic algorithm, with fitness evaluations performed via direct molecular dynamics simulation. We survey several initial materials design problems we have addressed with this framework and compare its performance to that of standard genetic algorithm approaches. We acknowledge the W. M. Keck Foundation for support of this work.

  3. CubeSat Material Limits For Design for Demise

    NASA Technical Reports Server (NTRS)

    Kelley, R. L.; Jarkey, D. R.

    2014-01-01

    The CubeSat form factor of nano-satellite (a satellite with a mass between one and ten kilograms) has grown in popularity due to their ease of construction and low development and launch costs. In particular, their use as student led payload design projects has increased due to the growing number of launch opportunities. CubeSats are often deployed as secondary or tertiary payloads on most US launch vehicles or they may be deployed from the ISS. The focus of this study will be on CubeSats launched from the ISS. From a space safety standpoint, the development and deployment processes for CubeSats differ significantly from that of most satellites. For large satellites, extensive design reviews and documentation are completed, including assessing requirements associated with reentry survivability. Typical CubeSat missions selected for ISS deployment have a less rigorous review process that may not evaluate aspects beyond overall design feasibility. CubeSat design teams often do not have the resources to ensure their design is compliant with reentry risk requirements. A study was conducted to examine methods to easily identify the maximum amount of a given material that can be used in the construction of a CubeSats without posing harm to persons on the ground. The results demonstrate that there is not a general equation or relationship that can be used for all materials; instead a limiting value must be defined for each unique material. In addition, the specific limits found for a number of generic materials that have been previously used as benchmarking materials for reentry survivability analysis tool comparison will be discussed.

  4. CubeSat Material Limits for Design for Demise

    NASA Technical Reports Server (NTRS)

    Kelley, R. L.; Jarkey, D. R.

    2014-01-01

    The CubeSat form factor of nano-satellite (a satellite with a mass between one and ten kilograms) has grown in popularity due to their ease of construction and low development and launch costs. In particular, their use as student led payload design projects has increased due to the growing number of launch opportunities. CubeSats are often deployed as secondary or tertiary payloads on most US launch vehicles or they may be deployed from the ISS. The focus of this study will be on CubeSats launched from the ISS. From a space safety standpoint, the development and deployment processes for CubeSats differ significantly from that of most satellites. For large satellites, extensive design reviews and documentation are completed, including assessing requirements associated with re-entry survivability. Typical CubeSat missions selected for ISS deployment have a less rigorous review process that may not evaluate aspects beyond overall design feasibility. CubeSat design teams often do not have the resources to ensure their design is compliant with re-entry risk requirements. A study was conducted to examine methods to easily identify the maximum amount of a given material that can be used in the construction of a CubeSats without posing harm to persons on the ground. The results demonstrate that there is not a general equation or relationship that can be used for all materials; instead a limiting value must be defined for each unique material. In addition, the specific limits found for a number of generic materials that have been previously used as benchmarking materials for re-entry survivability analysis tool comparison will be discussed.

  5. The design and modeling of periodic materials with novel properties

    NASA Astrophysics Data System (ADS)

    Berger, Jonathan Bernard

    Cellular materials are ubiquitous in our world being found in natural and engineered systems as structural materials, sound and energy absorbers, heat insulators and more. Stochastic foams made of polymers, metals and even ceramics find wide use due to their novel properties when compared to monolithic materials. Properties of these so called hybrid materials, those that combine materials or materials and space, are derived from the localization of thermomechanical stresses and strains on the mesoscale as a function of cell topology. The effects of localization can only be generalized in stochastic materials arising from their inherent potential complexity, possessing variations in local chemistry, microstructural inhomogeneity and topological variations. Ordered cellular materials on the other hand, such as lattices and honeycombs, make for much easier study, often requiring analysis of only a single unit-cell. Theoretical bounds predict that hybrid materials have the potential to push design envelopes offering lighter stiffer and stronger materials. Hybrid materials can achieve very low and even negative coefficients of thermal expansion (CTE) while retaining a relatively high stiffness -- properties completely unmatched by monolithic materials. In the first chapter of this thesis a two-dimensional lattice is detailed that possess near maximum stiffness, relative to the tightest theoretical bound, and low, zero and even appreciably negative thermal expansion. Its CTE and stiffness are given in closed form as a function of geometric parameters and the material properties. This result is confirmed with finite elements (FE) and experiment. In the second chapter the compressive stiffness of three-dimensional ordered foams, both closed and open cell, are predicted with FE and the results placed in property space in terms of stiffness and density. A novel structure is identified that effectively achieves theoretical bounds for Young's, shear and bulk modulus

  6. The radioactive materials packaging handbook: Design, operations, and maintenance

    SciTech Connect

    Shappert, L.B.; Bowman, S.M.; Arnold, E.D.

    1998-08-01

    As part of its required activities in 1994, the US Department of Energy (DOE) made over 500,000 shipments. Of these shipments, approximately 4% were hazardous, and of these, slightly over 1% (over 6,400 shipments) were radioactive. Because of DOE`s cleanup activities, the total quantities and percentages of radioactive material (RAM) that must be moved from one site to another is expected to increase in the coming years, and these materials are likely to be different than those shipped in the past. Irradiated fuel will certainly be part of the mix as will RAM samples and waste. However, in many cases these materials will be of different shape and size and require a transport packaging having different shielding, thermal, and criticality avoidance characteristics than are currently available. This Handbook provides guidance on the design, testing, certification, and operation of packages for these materials.

  7. Design of electro-active polymer gels as actuator materials

    NASA Astrophysics Data System (ADS)

    Popovic, Suzana

    Smart materials, alternatively called active or adaptive, differ from passive materials in their sensing and activation capability. These materials can sense changes in environment such as: electric field, magnetic field, UV light, pH, temperature. They are capable of responding in numerous ways. Some change their stiffness properties (electro-rheological fluids), other deform (piezos, shape memory alloys, electrostrictive materials) or change optic properties (electrochromic polymers). Polymer gels are one of such materials which can change the shape, volume and even optical properties upon different applied stimuli. Due to their low stiffness property they are capable of having up to 100% of strain in a short time, order of seconds. Their motion resembles the one of biosystems, and they are often seen as possible artificial muscle materials. Despite their delicate nature, appropriate design can make them being used as actuator materials which can form controllable surfaces and mechanical switches. In this study several different groups of polymer gel material were investigated: (a) acrylamide based gels are sensitive to pH and electric field and respond in volume change, (b) polyacrylonitrile (PAN) gel is sensitive to pH and electric field and responds in axial strain and bending, (c) polyvinylalcohol (PVA) gel is sensitive to electric field and responds in axial strain and bending and (d) perfluorinated sulfonic acid membrane, Nafion RTM, is sensitive to electric field and responds in bending. Electro-mechanical and chemo-mechanical behavior of these materials is a function of a variety of phenomena: polymer structure, affinity of polymer to the solvent, charge distribution within material, type of solvent, elasticity of polymer matrix, etc. Modeling of this behavior is a task aimed to identify what is driving mechanism for activation and express it in a quantitative way in terms of deformation of material. In this work behavior of the most promising material as

  8. Design of a Compact Fatigue Tester for Testing Irradiated Materials

    SciTech Connect

    Hartsell, Brian; Campbell, Michael; Fitton, Michael; Hurh, Patrick; Ishida, Taku; Nakadaira, Takeshi

    2015-06-01

    A compact fatigue testing machine that can be easily inserted into a hot cell for characterization of irradiated materials is beneficial to help determine relative fatigue performance differences between new and irradiated material. Hot cell use has been carefully considered by limiting the size and weight of the machine, simplifying sample loading and test setup for operation via master-slave manipulator, and utilizing an efficient design to minimize maintenance. Funded from a US-Japan collaborative effort, the machine has been specifically designed to help characterize titanium material specimens. These specimens are flat cantilevered beams for initial studies, possibly utilizing samples irradiated at other sources of beam. The option to test spherically shaped samples cut from the T2K vacuum window is also available. The machine is able to test a sample to $10^7$ cycles in under a week, with options to count cycles and sense material failure. The design of this machine will be presented along with current status.

  9. Bioinspiration from fish for smart material design and function

    NASA Astrophysics Data System (ADS)

    Lauder, G. V.; Madden, P. G. A.; Tangorra, J. L.; Anderson, E.; Baker, T. V.

    2011-09-01

    Fish are a potentially rich source of inspiration for the design of smart materials. Fish exemplify the use of flexible materials to generate forces during locomotion, and a hallmark of fish functional design is the use of body and fin deformation to power propulsion and maneuvering. As a result of nearly 500 million years of evolutionary experimentation, fish design has a number of interesting features of note to materials engineers. In this paper we first provide a brief general overview of some key features of the mechanical design of fish, and then focus on two key properties of fish: the bilaminar mechanical design of bony fish fin rays that allows active muscular control of curvature, and the role of body flexibility in propulsion. After describing the anatomy of bony fish fin rays, we provide new data on their mechanical properties. Three-point bending tests and measurement of force inputs to and outputs from the fin rays show that these fin rays are effective displacement transducers. Fin rays in different regions of the fin differ considerably in their material properties, and in the curvature produced by displacement of one of the two fin ray halves. The mean modulus for the proximal (basal) region of the fin rays was 1.34 GPa, but this varied from 0.24 to 3.7 GPa for different fin rays. The distal fin region was less stiff, and moduli for the different fin rays measured varied from 0.11 to 0.67 GPa. These data are similar to those for human tendons (modulus around 0.5 GPa). Analysis of propulsion using flexible foils controlled using a robotic flapping device allows investigation of the effect of altering flexural stiffness on swimming speed. Flexible foils with the leading edge moved in a heave show a distinct peak in propulsive performance, while the addition of pitch input produces a broad plateau where the swimming speed is relatively unaffected by the flexural stiffness. Our understanding of the material design of fish and the control of tissue

  10. Designed amyloid fibers as materials for selective carbon dioxide capture.

    PubMed

    Li, Dan; Furukawa, Hiroyasu; Deng, Hexiang; Liu, Cong; Yaghi, Omar M; Eisenberg, David S

    2014-01-01

    New materials capable of binding carbon dioxide are essential for addressing climate change. Here, we demonstrate that amyloids, self-assembling protein fibers, are effective for selective carbon dioxide capture. Solid-state NMR proves that amyloid fibers containing alkylamine groups reversibly bind carbon dioxide via carbamate formation. Thermodynamic and kinetic capture-and-release tests show the carbamate formation rate is fast enough to capture carbon dioxide by dynamic separation, undiminished by the presence of water, in both a natural amyloid and designed amyloids having increased carbon dioxide capacity. Heating to 100 °C regenerates the material. These results demonstrate the potential of amyloid fibers for environmental carbon dioxide capture.

  11. Photovoltaic module encapsulation design and materials selection. Volume II

    SciTech Connect

    Cuddihy, E.

    1984-06-01

    This is Volume II of Photovoltaic Module Encapsulation Design and Materials Selection: a periodically updated handbook of encapsulation technology, developed with the support of the Flat-Plate Solar Array Project (FSA), managed for the Department of Energy (DOE) by the Jet Propulsion Laboratory. Volume II describes FSA encapsulation technology developed between June 1, 1982, and January 1, 1984. Emphasis during this period shifted from materials development to demonstration of reliability and durability in an outdoor environment; the updated information in this volume reflects the developing technology base related to both reliability and encapsulation process improvements.

  12. Tunable structural color in organisms and photonic materials for design of bioinspired materials

    NASA Astrophysics Data System (ADS)

    Fudouzi, Hiroshi

    2011-12-01

    In this paper, the key topics of tunable structural color in biology and material science are overviewed. Color in biology is considered for selected groups of tropical fish, octopus, squid and beetle. It is caused by nanoplates in iridophores and varies with their spacing, tilting angle and refractive index. These examples may provide valuable hints for the bioinspired design of photonic materials. 1D multilayer films and 3D colloidal crystals with tunable structural color are overviewed from the viewpoint of advanced materials. The tunability of structural color by swelling and strain is demonstrated on an example of opal composites.

  13. Advanced aerospace composite material structural design using artificial intelligent technology

    SciTech Connect

    Sun, S.H.; Chen, J.L.; Hwang, W.C.

    1993-12-31

    Due to the complexity in the prediction of property and behavior, composite material has not substituted for metal widely yet, though it has high specific-strength and high specific-modulus that are more important in the aerospace industry. In this paper two artificial intelligent techniques, the expert systems and neural network technology, were introduced to the structural design of composite material. Expert System which has good ability in symbolic processing can helps us to solve problem by saving experience and knowledge. It is, therefore, a reasonable way to combine expert system technology to tile composite structural design. The development of a prototype expert system to help designer during the process of composite structural design is presented. Neural network is a network similar to people`s brain that can simulate the thinking way of people and has the ability of learning from the training data by adapting the weights of network. Because of the bottleneck in knowledge acquisition processes, the application of neural network and its learning ability to strength design of composite structures are presented. Some examples are in this paper to demonstrate the idea.

  14. System design considerations for free-fall materials processing

    NASA Technical Reports Server (NTRS)

    Seidensticker, R. G.

    1974-01-01

    The design constraints for orbiting materials processing systems are dominated by the limitations of the flight vehicle/crew and not by the processes themselves. Although weight, size and power consumption are all factors in the design of normal laboratory equipment, their importance is increased orders of magnitude when the equipment must be used in an orbital facility. As a result, equipment intended for space flight may have little resemblance to normal laboratory apparatus although the function to be performed may be identical. The same considerations influence the design of the experiment itself. The processing requirements must be carefully understood in terms of basic physical parameters rather than defined in terms of equipment operation. Preliminary experiments and analysis are much more vital to the design of a space experiment than they are on earth where iterative development is relatively easy. Examples of these various considerations are illustrated with examples from the M518 and MA-010 systems. While these are specific systems, the conclusions apply to the design of flight materials processing systems both present and future.

  15. Exascale Co-design for Modeling Materials in Extreme Environments

    SciTech Connect

    Germann, Timothy C.

    2014-07-08

    Computational materials science has provided great insight into the response of materials under extreme conditions that are difficult to probe experimentally. For example, shock-induced plasticity and phase transformation processes in single-crystal and nanocrystalline metals have been widely studied via large-scale molecular dynamics simulations, and many of these predictions are beginning to be tested at advanced 4th generation light sources such as the Advanced Photon Source (APS) and Linac Coherent Light Source (LCLS). I will describe our simulation predictions and their recent verification at LCLS, outstanding challenges in modeling the response of materials to extreme mechanical and radiation environments, and our efforts to tackle these as part of the multi-institutional, multi-disciplinary Exascale Co-design Center for Materials in Extreme Environments (ExMatEx). ExMatEx has initiated an early and deep collaboration between domain (computational materials) scientists, applied mathematicians, computer scientists, and hardware architects, in order to establish the relationships between algorithms, software stacks, and architectures needed to enable exascale-ready materials science application codes within the next decade. We anticipate that we will be able to exploit hierarchical, heterogeneous architectures to achieve more realistic large-scale simulations with adaptive physics refinement, and are using tractable application scale-bridging proxy application testbeds to assess new approaches and requirements. Such current scale-bridging strategies accumulate (or recompute) a distributed response database from fine-scale calculations, in a top-down rather than bottom-up multiscale approach.

  16. Rational Design of Pathogen-Mimicking Amphiphilic Materials as Nanoadjuvants

    NASA Astrophysics Data System (ADS)

    Ulery, Bret D.; Petersen, Latrisha K.; Phanse, Yashdeep; Kong, Chang Sun; Broderick, Scott R.; Kumar, Devender; Ramer-Tait, Amanda E.; Carrillo-Conde, Brenda; Rajan, Krishna; Wannemuehler, Michael J.; Bellaire, Bryan H.; Metzger, Dennis W.; Narasimhan, Balaji

    2011-12-01

    An opportunity exists today for cross-cutting research utilizing advances in materials science, immunology, microbial pathogenesis, and computational analysis to effectively design the next generation of adjuvants and vaccines. This study integrates these advances into a bottom-up approach for the molecular design of nanoadjuvants capable of mimicking the immune response induced by a natural infection but without the toxic side effects. Biodegradable amphiphilic polyanhydrides possess the unique ability to mimic pathogens and pathogen associated molecular patterns with respect to persisting within and activating immune cells, respectively. The molecular properties responsible for the pathogen-mimicking abilities of these materials have been identified. The value of using polyanhydride nanovaccines was demonstrated by the induction of long-lived protection against a lethal challenge of Yersinia pestis following a single administration ten months earlier. This approach has the tantalizing potential to catalyze the development of next generation vaccines against diseases caused by emerging and re-emerging pathogens.

  17. A model for designing functionally gradient material joints

    SciTech Connect

    Messler, R.W. Jr.; Jou, M.; Orling, T.T.

    1995-05-01

    An analytical, thin-plate layer model was developed to assist research and development engineers in the design of functionally gradient material (FGM) joints consisting of discrete steps between end elements of dissimilar materials. Such joints have long been produced by diffusion bonding using intermediates or multiple interlayers; welding, brazing or soldering using multiple transition pieces; and glass-to-glass or glass-to-metal bonding using multiple layers to produce matched seals. More recently, FGM joints produced by self-propagating high-temperature synthesis (SHS) are attracting the attention of researchers. The model calculates temperature distributions and associated thermally induced stresses, assuming elastic behavior, for any number of layers of any thickness or composition, accounting for critically important thermophysical properties in each layer as functions of temperature. It is useful for assuring that cured-in fabrication stresses from thermal expansion mismatches will not prevent quality joint production. The model`s utility is demonstrated with general design cases.

  18. Solid-fluid mixture microstructure design of composite materials with application to tissue engineering scaffold design

    NASA Astrophysics Data System (ADS)

    Lin, Cheng-Yu

    The ability to design the material microstructure brings the use of composite materials into the next generation. In this paper, we report pioneering research to implement the computational material microstructure design into the internal architecture design for a tissue engineering scaffold. A tissue engineering design postulate is that scaffolds should match specified healthy tissue stiffness, while concurrently providing sufficient porosity for cell migration and tissue regeneration. Employing the inverse homogenization method and the adaptive topology optimization method, a complex 3D microstructure can be designed to perform with the anisotropic elastic stiffness and porosities analogous to a native bone specimen. Besides the elastic stiffness from its solid part, fluid in the porous region also plays an important role in tissue engineering. The flow of fluid through the pores brings nutrients to cells in the tissue matrix and also removes their waste. Fluid permeability of cylinderical trabecular bone grafts was found to predict clinical success. Deriving from Darcy's Law, we developed software to calculate the homogenized fluid permeability of 3D cancellous voxel models, which were directly reconstructed from micro-CT images. Furthermore, an Evolutionary Structural Optimization (ESO) algorithm was utilized to maximize fluid permeability in the microstructure. The fluid optimization scheme was then collaborated with solid phase optimization through Multidisciplinary Design Optimization (MDO) to create an integrated solid-fluid mixture microstructure design. In addition, to ensure the fabrication feasibility, we also implemented a post-optimization process to enhance design results by improving the dynamic stiffness to eliminate weak connections and checkerboard pattern. The design scaffolds were then built by an indirect solid freeform fabrication (SFF) technique using various bio-compatible materials and ready for further investment. This computational

  19. Thermo-magnetic materials for use in designing intelligent actuators

    SciTech Connect

    Ohtani, Yoshimutsu; Yoshimura, Fumikatsu; Hatakeyama, Iwao; Ishii, Yoshikazu

    1994-12-31

    The authors present the concept of an intelligent thermal actuator designed by using thermally sensitive magnetic materials. The use of the magnetic transition of FeRh alloy is very effective in increasing the actuator functions. These functions are freedom of direction, tuning temperature, and increasing both sensitivity and power. Two new types of actuator, a remote controlled optical driven thermo-magnetic motor and a temperature sensitive spring-less valve, are proposed and experimental results are shown.

  20. Module Design, Materials, and Packaging Research Team: Activities and Capabilities

    SciTech Connect

    McMahon, T. J.; del Cueto, J.; Glick, S.; Jorgensen, G.; Kempe, M.; Kennedy, C.; Pern, J.; Terwilliger, K

    2005-01-01

    Our team activities are directed at improving PV module reliability by incorporating new, more effective, and less expensive packaging materials and techniques. New and existing materials or designs are evaluated before and during accelerated environmental exposure for the following properties: (1) Adhesion and cohesion: peel strength and lap shear. (2) Electrical conductivity: surface, bulk, interface and transients. (3) Water vapor transmission: solubility and diffusivity. (4) Accelerated weathering: ultraviolet, temperature, and damp heat tests. (5) Module and cell failure diagnostics: infrared imaging, individual cell shunt characterization, coring. (6) Fabrication improvements: SiOxNy barrier coatings and enhanced wet adhesion. (7) Numerical modeling: Moisture ingress/egress, module and cell performance, and cell-to-frame leakage current. (8) Rheological properties of polymer encapsulant and sheeting materials. Specific examples will be described.

  1. Design of Responsive and Active (Soft) Materials Using Liquid Crystals.

    PubMed

    Bukusoglu, Emre; Bedolla Pantoja, Marco; Mushenheim, Peter C; Wang, Xiaoguang; Abbott, Nicholas L

    2016-06-01

    Liquid crystals (LCs) are widely known for their use in liquid crystal displays (LCDs). Indeed, LCDs represent one of the most successful technologies developed to date using a responsive soft material: An electric field is used to induce a change in ordering of the LC and thus a change in optical appearance. Over the past decade, however, research has revealed the fundamental underpinnings of potentially far broader and more pervasive uses of LCs for the design of responsive soft material systems. These systems involve a delicate interplay of the effects of surface-induced ordering, elastic strain of LCs, and formation of topological defects and are characterized by a chemical complexity and diversity of nano- and micrometer-scale geometry that goes well beyond that previously investigated. As a reflection of this evolution, the community investigating LC-based materials now relies heavily on concepts from colloid and interface science. In this context, this review describes recent advances in colloidal and interfacial phenomena involving LCs that are enabling the design of new classes of soft matter that respond to stimuli as broad as light, airborne pollutants, bacterial toxins in water, mechanical interactions with living cells, molecular chirality, and more. Ongoing efforts hint also that the collective properties of LCs (e.g., LC-dispersed colloids) will, over the coming decade, yield exciting new classes of driven or active soft material systems in which organization (and useful properties) emerges during the dissipation of energy. PMID:26979412

  2. Design of Responsive and Active (Soft) Materials Using Liquid Crystals.

    PubMed

    Bukusoglu, Emre; Bedolla Pantoja, Marco; Mushenheim, Peter C; Wang, Xiaoguang; Abbott, Nicholas L

    2016-06-01

    Liquid crystals (LCs) are widely known for their use in liquid crystal displays (LCDs). Indeed, LCDs represent one of the most successful technologies developed to date using a responsive soft material: An electric field is used to induce a change in ordering of the LC and thus a change in optical appearance. Over the past decade, however, research has revealed the fundamental underpinnings of potentially far broader and more pervasive uses of LCs for the design of responsive soft material systems. These systems involve a delicate interplay of the effects of surface-induced ordering, elastic strain of LCs, and formation of topological defects and are characterized by a chemical complexity and diversity of nano- and micrometer-scale geometry that goes well beyond that previously investigated. As a reflection of this evolution, the community investigating LC-based materials now relies heavily on concepts from colloid and interface science. In this context, this review describes recent advances in colloidal and interfacial phenomena involving LCs that are enabling the design of new classes of soft matter that respond to stimuli as broad as light, airborne pollutants, bacterial toxins in water, mechanical interactions with living cells, molecular chirality, and more. Ongoing efforts hint also that the collective properties of LCs (e.g., LC-dispersed colloids) will, over the coming decade, yield exciting new classes of driven or active soft material systems in which organization (and useful properties) emerges during the dissipation of energy.

  3. Design And Formability Of A New Composite Material

    NASA Astrophysics Data System (ADS)

    Bolay, C.; Liewald, M.

    2011-05-01

    Composite materials with metallic cover sheets have been established based on their low weight potential in industrial applications. Further requirements such as high stiffness of component, vibration damping and formability today are only partially met by these composites. For that reason, in current research work, great efforts are being made to develop materials which can be adapted to their later use and load in terms of improving noise, vibration and harshness. Thus, greater stiffness of component structure with a simultaneous reduction of weight can be achieved. This article presents a new composite material which consists of a plane sheet, a thin intermediate damping-layer and a sheet with formed elements to increase stiffness of component such as beads. The plane side can be used as the visible part side. The shape elements increase strength due to work hardening and can be used as design or functional elements. Thus, this composite material results in several advantages within the single layers. Possible flexibility in component design enables new semi-finished or tailored components.

  4. Design of Functional Materials based on Liquid Crystalline Droplets

    PubMed Central

    Miller, Daniel S.; Wang, Xiaoguang; Abbott, Nicholas L.

    2014-01-01

    This brief perspective focuses on recent advances in the design of functional soft materials that are based on confinement of low molecular weight liquid crystals (LCs) within micrometer-sized droplets. While the ordering of LCs within micrometer-sized domains has been explored extensively in polymer-dispersed LC materials, recent studies performed with LC domains with precisely defined size and interfacial chemistry have unmasked observations of confinement-induced ordering of LCs that do not follow previously reported theoretical predictions. These new findings, which are enabled in part by advances in the preparation of LCs encapsulated in polymeric shells, are opening up new opportunities for the design of soft responsive materials based on surface-induced ordering transitions. These materials are also providing new insights into the self-assembly of biomolecular and colloidal species at defects formed by LCs confined to micrometer-sized domains. The studies presented in this perspective serve additionally to highlight gaps in knowledge regarding the ordering of LCs in confined systems. PMID:24882944

  5. Textile materials for the design of wearable antennas: a survey.

    PubMed

    Salvado, Rita; Loss, Caroline; Gonçalves, Ricardo; Pinho, Pedro

    2012-11-15

    In the broad context of Wireless Body Sensor Networks for healthcare and pervasive applications, the design of wearable antennas offers the possibility of ubiquitous monitoring, communication and energy harvesting and storage. Specific requirements for wearable antennas are a planar structure and flexible construction materials. Several properties of the materials influence the behaviour of the antenna. For instance, the bandwidth and the efficiency of a planar microstrip antenna are mainly determined by the permittivity and the thickness of the substrate. The use of textiles in wearable antennas requires the characterization of their properties. Specific electrical conductive textiles are available on the market and have been successfully used. Ordinary textile fabrics have been used as substrates. However, little information can be found on the electromagnetic properties of regular textiles. Therefore this paper is mainly focused on the analysis of the dielectric properties of normal fabrics. In general, textiles present a very low dielectric constant that reduces the surface wave losses and increases the impedance bandwidth of the antenna. However, textile materials are constantly exchanging water molecules with the surroundings, which affects their electromagnetic properties. In addition, textile fabrics are porous, anisotropic and compressible materials whose thickness and density might change with low pressures. Therefore it is important to know how these characteristics influence the behaviour of the antenna in order to minimize unwanted effects. This paper presents a survey of the key points for the design and development of textile antennas, from the choice of the textile materials to the framing of the antenna. An analysis of the textile materials that have been used is also presented.

  6. Design and preparation of materials for advanced electrochemical storage.

    PubMed

    Melot, Brent C; Tarascon, J-M

    2013-05-21

    To meet the growing global demand for energy while preserving the environment, it is necessary to drastically reduce the world's dependence on non-renewable energy sources. At the core of this effort will be the ability to efficiently convert, store, transport and access energy in a variety of ways. Batteries for use in small consumer devices have saturated society; however, if they are ever to be useful in large-scale applications such as automotive transportation or grid-storage, they will require new materials with dramatically improved performance. Efforts must also focus on using Earth-abundant and nontoxic compounds so that whatever developments are made will not create new environmental problems. In this Account, we describe a general strategy for the design and development of new insertion electrode materials for Li(Na)-ion batteries that meet these requirements. We begin by reviewing the current state of the art of insertion electrodes and highlighting the intrinsic material properties of electrodes that must be re-engineered for extension to larger-scale applications. We then present a detailed discussion of the relevant criteria for the conceptual design and appropriate selection of new electrode chemical compositions. We describe how the open-circuit voltage of Li-ion batteries can be manipulated and optimized through structural and compositional tuning by exploiting differences in the electronegativity among possible electrode materials. We then discuss which modern synthetic techniques are most sustainable, allowing the creation of new materials via environmentally responsible reactions that minimize the use of energy and toxic solvents. Finally, we present a case study showing how we successfully employed these approaches to develop a large number of new, useful electrode materials within the recently discovered family of transition metal fluorosulfates. This family has attracted interest as a possible source of improved Li-ion batteries in larger

  7. Textile materials for the design of wearable antennas: a survey.

    PubMed

    Salvado, Rita; Loss, Caroline; Gonçalves, Ricardo; Pinho, Pedro

    2012-01-01

    In the broad context of Wireless Body Sensor Networks for healthcare and pervasive applications, the design of wearable antennas offers the possibility of ubiquitous monitoring, communication and energy harvesting and storage. Specific requirements for wearable antennas are a planar structure and flexible construction materials. Several properties of the materials influence the behaviour of the antenna. For instance, the bandwidth and the efficiency of a planar microstrip antenna are mainly determined by the permittivity and the thickness of the substrate. The use of textiles in wearable antennas requires the characterization of their properties. Specific electrical conductive textiles are available on the market and have been successfully used. Ordinary textile fabrics have been used as substrates. However, little information can be found on the electromagnetic properties of regular textiles. Therefore this paper is mainly focused on the analysis of the dielectric properties of normal fabrics. In general, textiles present a very low dielectric constant that reduces the surface wave losses and increases the impedance bandwidth of the antenna. However, textile materials are constantly exchanging water molecules with the surroundings, which affects their electromagnetic properties. In addition, textile fabrics are porous, anisotropic and compressible materials whose thickness and density might change with low pressures. Therefore it is important to know how these characteristics influence the behaviour of the antenna in order to minimize unwanted effects. This paper presents a survey of the key points for the design and development of textile antennas, from the choice of the textile materials to the framing of the antenna. An analysis of the textile materials that have been used is also presented. PMID:23202235

  8. Chalcogenide Glass Radiation Sensor; Materials Development, Design and Device Testing

    SciTech Connect

    Mitkova, Maria; Butt, Darryl; Kozicki, Michael; Barnaby, Hugo

    2013-04-30

    studied the effect of x-rays and γ-rays, on thin film chalcogenide glasses and applied them in conjunction with film incorporating a silver source in a new type of radiation sensor for which we have an US patent application [3]. In this report, we give data about our studies regarding our designed radiation sensor along with the testing and performance at various radiation doses. These studies have been preceded by materials characterization research related to the compositional and structural characteristics of the active materials used in the radiation sensor design. During the work on the project, we collected a large volume of material since every experiment was repeated many times to verify the results. We conducted a comprehensive material research, analysis and discussion with the aim to understand the nature of the occurring effects, design different structures to harness these effects, generated models to aid in the understanding the effects, built different device structures and collected data to quantify device performance. These various aspects of our investigation have been detailed in previous quarterly reports. In this report, we present our main results and emphasize on the results pertaining to the core project goals materials development, sensor design and testing and with an emphasis on classifying the appropriate material and design for the optimal application. The report has three main parts: (i) Presentation of the main data; (ii) Bulleted summary of the most important results; (iii) List of the patent, journal publications, conference proceedings and conferences participation, occurring as a result of working on the project.

  9. Designs and Materials for Better Coronagraph Occulting Masks

    NASA Technical Reports Server (NTRS)

    Balasubramanian, Kunjithapatham

    2010-01-01

    New designs, and materials appropriate for such designs, are under investigation in an effort to develop coronagraph occulting masks having broad-band spectral characteristics superior to those currently employed. These designs and materials are applicable to all coronagraphs, both ground-based and spaceborne. This effort also offers potential benefits for the development of other optical masks and filters that are required (1) for precisely tailored spatial transmission profiles, (2) to be characterized by optical-density neutrality and phase neutrality (that is, to be characterized by constant optical density and constant phase over broad wavelength ranges), and/or (3) not to exhibit optical- density-dependent phase shifts. The need for this effort arises for the following reasons: Coronagraph occulting masks are required to impose, on beams of light transmitted through them, extremely precise control of amplitude and phase according to carefully designed transmission profiles. In the original application that gave rise to this effort, the concern has been to develop broad-band occulting masks for NASA s Terrestrial Planet Finder coronagraph. Until now, experimental samples of these masks have been made from high-energy-beam-sensitive (HEBS) glass, which becomes locally dark where irradiated with a high-energy electron beam, the amount of darkening depending on the electron-beam energy and dose. Precise mask profiles have been written on HEBS glass blanks by use of electron beams, and the masks have performed satisfactorily in monochromatic light. However, the optical-density and phase profiles of the HEBS masks vary significantly with wavelength; consequently, the HEBS masks perform unsatisfactorily in broad-band light. The key properties of materials to be used in coronagraph occulting masks are their extinction coefficients, their indices of refraction, and the variations of these parameters with wavelength. The effort thus far has included theoretical

  10. The application of composite materials to spaceborne radiometer instrument design

    NASA Astrophysics Data System (ADS)

    Hookman, Robert A.; Zurmehly, George E.

    1990-10-01

    The stability and coregistration requirements for future radiometric instrument designs spawn the need for a totally integrated instrument structure and thermal control scheme. To meet the requirements of the future Geostationary meteorological missions an Ultra Stable Instrument Structure (USIS) will be needed. An instrument structure of lightweight construction is described that takes advantage of composite materials that combine high stiffness, low density along with low Coefficient of Thermal Expansion (CTE). In addition, this paper will outline the mission objectives, the operating environment and stability requirements needed for future spaceborne radiometer structures. A conceptual design of a composite instrument structure along with its thermal control system will be outlined, and various design trade-offs will be presented.

  11. 14 CFR 23.613 - Material strength properties and design values.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Material strength properties and design... Design and Construction § 23.613 Material strength properties and design values. (a) Material strength properties must be based on enough tests of material meeting specifications to establish design values on...

  12. 14 CFR 23.613 - Material strength properties and design values.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Material strength properties and design... Design and Construction § 23.613 Material strength properties and design values. (a) Material strength properties must be based on enough tests of material meeting specifications to establish design values on...

  13. Interfacial properties and design of functional energy materials.

    PubMed

    Sumpter, Bobby G; Liang, Liangbo; Nicolaï, Adrien; Meunier, Vincent

    2014-11-18

    CONSPECTUS: The vital importance of energy to society continues to demand a relentless pursuit of energy responsive materials that can bridge fundamental chemical structures at the molecular level and achieve improved functionality and performance. This demand can potentially be realized by harnessing the power of self-assembly, a spontaneous process where molecules or much larger entities form ordered aggregates as a consequence of predominately noncovalent (weak) interactions. Self-assembly is the key to bottom-up design of molecular devices, because the nearly atomic-level control is very difficult to realize in a top-down, for example, lithographic, approach. However, while function in simple systems such as single crystals can often be evaluated a priori, predicting the function of the great variety of self-assembled molecular architectures is complicated by the lack of understanding and control over nanoscale interactions, mesoscale architectures, and macroscale order. To establish a foundation toward delivering practical solutions, it is critical to develop an understanding of the chemical and physical mechanisms responsible for the self-assembly of molecular and hybrid materials on various support substrates. Typical molecular self-assembly involves noncovalent intermolecular and substrate-molecule interactions. These interactions remain poorly understood, due to the combination of many-body interactions compounded by local or collective influences from the substrate atomic lattice and electronic structure. Progress toward unraveling the underlying physicochemical processes that control the structure and macroscopic physical, chemical, mechanical, electrical, and transport properties of materials increasingly requires tight integration of theory, modeling, and simulation with precision synthesis, advanced experimental characterization, and device measurements. Theory, modeling, and simulation can accelerate the process of materials understanding and design

  14. Interfacial properties and design of functional energy materials.

    PubMed

    Sumpter, Bobby G; Liang, Liangbo; Nicolaï, Adrien; Meunier, Vincent

    2014-11-18

    CONSPECTUS: The vital importance of energy to society continues to demand a relentless pursuit of energy responsive materials that can bridge fundamental chemical structures at the molecular level and achieve improved functionality and performance. This demand can potentially be realized by harnessing the power of self-assembly, a spontaneous process where molecules or much larger entities form ordered aggregates as a consequence of predominately noncovalent (weak) interactions. Self-assembly is the key to bottom-up design of molecular devices, because the nearly atomic-level control is very difficult to realize in a top-down, for example, lithographic, approach. However, while function in simple systems such as single crystals can often be evaluated a priori, predicting the function of the great variety of self-assembled molecular architectures is complicated by the lack of understanding and control over nanoscale interactions, mesoscale architectures, and macroscale order. To establish a foundation toward delivering practical solutions, it is critical to develop an understanding of the chemical and physical mechanisms responsible for the self-assembly of molecular and hybrid materials on various support substrates. Typical molecular self-assembly involves noncovalent intermolecular and substrate-molecule interactions. These interactions remain poorly understood, due to the combination of many-body interactions compounded by local or collective influences from the substrate atomic lattice and electronic structure. Progress toward unraveling the underlying physicochemical processes that control the structure and macroscopic physical, chemical, mechanical, electrical, and transport properties of materials increasingly requires tight integration of theory, modeling, and simulation with precision synthesis, advanced experimental characterization, and device measurements. Theory, modeling, and simulation can accelerate the process of materials understanding and design

  15. New approach to design of ceramic/polymer material compounds

    NASA Astrophysics Data System (ADS)

    Todt, A.; Nestler, D.; Trautmann, M.; Wagner, G.

    2016-03-01

    The damage tolerance of carbon fibre-reinforced ceramic-matrix composite materials depends on their porosity and can be rather significant. Complex structures are difficult to produce. The integration of simple geometric structures of ceramic-matrix composite materials in complex polymer-based hybrid structures is a possible approach of realising those structures. These hybrid material compounds, produced in a cost-efficient way, combine the different advantages of the individual components in one hybrid material compound. In addition the individual parts can be designed to fit a specific application and the resulting forces. All these different advantages result in a significant reduction of not only the production costs and the production time, but also opens up new areas of application, such as the large-scale production of wear-resistant and chemically inert, energy dampening components for reactors or in areas of medicine. The low wettability of the ceramic component however is a disadvantage of this approach. During the course of this contribution, different C/C composite materials with a specific porosity were produced, while adjusting the resin/hardening agent-ratio, as well as the processing parameters. After the production, different penetration tests were conducted with a polymer component. The final part of the article is comprised of the microstructural analysis and the explanation of the mechanical relationships.

  16. Design Molecular Recognition Materials for Chiral Sensors, Separtations and Catalytic Materials

    SciTech Connect

    Jia, S.; Nenoff, T.M.; Provencio, P.; Qiu, Y.; Shelnutt, J.A.; Thoma, S.G.; Zhang, J.

    1998-11-01

    The goal is the development of materials that are highly sensitive and selective for chid chemicals and biochemical (such as insecticides, herbicides, proteins, and nerve agents) to be used as sensors, catalysts and separations membranes. Molecular modeling methods are being used to tailor chiral molecular recognition sites with high affinity and selectivity for specified agents. The work focuses on both silicate and non-silicate materials modified with chirally-pure fictional groups for the catalysis or separations of enantiomerically-pure molecules. Surfactant and quaternary amine templating is being used to synthesize porous frameworks, containing mesopores of 30 to 100 angstroms. Computer molecukw modeling methods are being used in the design of these materials, especially in the chid surface- modi~ing agents. Molecular modeling is also being used to predict the catalytic and separations selectivities of the modified mesoporous materials. The ability to design and synthesize tailored asymmetric molecular recognition sites for sensor coatings allows a broader range of chemicals to be sensed with the desired high sensitivity and selectivity. Initial experiments target the selective sensing of small molecule gases and non-toxic model neural compounds. Further efforts will address designing sensors that greatly extend the variety of resolvable chemical species and forming a predictive, model-based method for developing advanced sensors.

  17. System design for safe robotic handling of nuclear materials

    SciTech Connect

    Drotning, W.; Wapman, W.; Fahrenholtz, J.; Kimberly, H.; Kuhlmann, J.

    1996-03-01

    Robotic systems are being developed by the Intelligent Systems and Robotics Center at Sandia National Laboratories to perform automated handling tasks with radioactive nuclear materials. These systems will reduce the occupational radiation exposure to workers by automating operations which are currently performed manually. Because the robotic systems will handle material that is both hazardous and valuable, the safety of the operations is of utmost importance; assurance must be given that personnel will not be harmed and that the materials and environment will be protected. These safety requirements are met by designing safety features into the system using a layered approach. Several levels of mechanical, electrical and software safety prevent unsafe conditions from generating a hazard, and bring the system to a safe state should an unexpected situation arise. The system safety features include the use of industrial robot standards, commercial robot systems, commercial and custom tooling, mechanical safety interlocks, advanced sensor systems, control and configuration checks, and redundant control schemes. The effectiveness of the safety features in satisfying the safety requirements is verified using a Failure Modes and Effects Analysis. This technique can point out areas of weakness in the safety design as well as areas where unnecessary redundancy may reduce the system reliability.

  18. Advanced composite structures. [metal matrix composites - structural design criteria for spacecraft construction materials

    NASA Technical Reports Server (NTRS)

    1974-01-01

    A monograph is presented which establishes structural design criteria and recommends practices to ensure the design of sound composite structures, including composite-reinforced metal structures. (It does not discuss design criteria for fiber-glass composites and such advanced composite materials as beryllium wire or sapphire whiskers in a matrix material.) Although the criteria were developed for aircraft applications, they are general enough to be applicable to space vehicles and missiles as well. The monograph covers four broad areas: (1) materials, (2) design, (3) fracture control, and (4) design verification. The materials portion deals with such subjects as material system design, material design levels, and material characterization. The design portion includes panel, shell, and joint design, applied loads, internal loads, design factors, reliability, and maintainability. Fracture control includes such items as stress concentrations, service-life philosophy, and the management plan for control of fracture-related aspects of structural design using composite materials. Design verification discusses ways to prove flightworthiness.

  19. Test model designs for advanced refractory ceramic materials

    NASA Technical Reports Server (NTRS)

    Tran, Huy Kim

    1993-01-01

    The next generation of space vehicles will be subjected to severe aerothermal loads and will require an improved thermal protection system (TPS) and other advanced vehicle components. In order to ensure the satisfactory performance system (TPS) and other advanced vehicle materials and components, testing is to be performed in environments similar to space flight. The design and fabrication of the test models should be fairly simple but still accomplish test objectives. In the Advanced Refractory Ceramic Materials test series, the models and model holders will need to withstand the required heat fluxes of 340 to 817 W/sq cm or surface temperatures in the range of 2700 K to 3000 K. The model holders should provide one dimensional (1-D) heat transfer to the samples and the appropriate flow field without compromising the primary test objectives. The optical properties such as the effective emissivity, catalytic efficiency coefficients, thermal properties, and mass loss measurements are also taken into consideration in the design process. Therefore, it is the intent of this paper to demonstrate the design schemes for different models and model holders that would accommodate these test requirements and ensure the safe operation in a typical arc jet facility.

  20. The design, synthesis, and characterization of novel electronic organic materials

    NASA Astrophysics Data System (ADS)

    Walker, Wesley Thomas

    pi-conjugated organic molecules have proven to be valuable tools for organic electronics and engineered materials. The ability to manipulate the structure and energy levels of these materials allows them to be tailored to meet the electronic and physical demands of a variety of devices. One particular interest in this field is low band gap organic polymers, specifically those with band gaps below 1.5 eV; these are typically designed by constructing polymers with alternating donor and acceptor moieties in the conjugated backbone of the molecule. An additional area of interest for pi-conjugated organic molecules has been the search for solution-processable small molecules for use in organic solar cells and organic light emitting diodes. Owing to poor film morphologies resulting from solution casting, small molecules are largely thermally deposited, thus limiting the scope to which they can be utilized in devices. This dissertation will outline the design, synthesis, and characterization of a series of low band gap organic polymers with a design motif of alternating thiophene-cyclopentadienone units, resulting in polymers that are shown to have absorptions throughout the visible spectrum and into the infrared, as well as the synthesis and characterization of two classes of small solution processable conjugated molecules: dinaphthocarbazoles and triphenylfluoranthenes.

  1. A model for designing functionally gradient material joints

    SciTech Connect

    Jou, M.; Messler, R.W.; Orling, T.T.

    1994-12-31

    Joining of dissimilar materials into hybrid structures to meet severe design and service requirements is becoming more necessary and common. Joints between heat-resisting or refractory metals and refractory or corrosion resistant ceramics and intermetallics are especially in demand. Before resorting to a more complicated but versatile finite element analysis (FEA) model, a simpler, more user-friendly analytical layer-model based on a thin plate assumption was developed and tested. The model has been successfully used to design simple FGM joints between Ni-base superalloys or Mo and SiC, Ni{sub 3}Al or Al{sub 2}O{sub 3} using self-propagating high-temperature or pressurized composition synthesis for joining. Cases are presented to demonstrate capability for: (1) varying processing temperature excursions or service gradients; (2) varying overall joint thickness for a fixed number of uniform composition steps; (3) varying the number of uniform steps for a particular overall joint thickness; (4) varying the thickness and/or composition of individual steps for a constant overall thickness; and (5) altering the constitutive law for mixed-material composition steps. The model provides a useful joint design tool for process R&D.

  2. Acentric lattice electro-optic materials by rational design

    NASA Astrophysics Data System (ADS)

    Dalton, Larry; Robinson, Bruce; Jen, Alex; Ried, Philip; Eichinger, Bruce; Sullivan, Philip; Akelaitis, Andrew; Bale, Denise; Haller, Marnie; Luo, Jingdong; Liu, Sen; Liao, Yi; Firestone, Kimberly; Bhatambrekar, Nishant; Bhattacharjee, Sanchali; Sinness, Jessica; Hammond, Scott; Buker, Nicholas; Snoeberger, Robert; Lingwood, Mark; Rommel, Harry; Amend, Joe; Jang, Sei-Hum; Chen, Antao; Steier, William

    2005-08-01

    Quantum and statistical mechanical calculations have been used to guide the improvement of the macroscopic electro-optic activity of organic thin film materials to values greater than 300 pm/V at telecommunication wavelengths. Various quantum mechanical methods (Hartree-Fock, INDO, and density functional theory) have been benchmarked and shown to be reliable for estimating trends in molecular first hyperpolarizability, β, for simple variation of donor, bridge, and acceptor structures of charge-transfer (dipolar) chromophores. β values have been increased significantly over the past five years and quantum mechanical calculations suggest that they can be further significantly improved. Statistical mechanical calculations, including pseudo-atomistic Monte Carlo calculations, have guided the design of the super/supramolecular structures of chromophores so that they assemble, under the influence of electric field poling, into macroscopic lattices with high degrees of acentric order. Indeed, during the past year, chromophores doped into single- and multi-chromophore-containing dendrimer materials to form binary glasses have yielded thin films that exhibit electro-optic activities at telecommunication wavelengths of greater than 300 pm/V. Such materials may be viewed as intermediate between chromophore/polymer composites and crystalline organic chromophore materials. Theory suggests that further improvements of electro-optic activity are possible. Auxiliary properties of these materials, including optical loss, thermal and photochemical stability, and processability are discussed. Such organic electro-optic materials have been incorporated into silicon photonic circuitry for active wavelength division multiplexing, reconfigurable optical add/drop multiplexing, and high bandwidth optical rectification. A variety of all-organic devices, including stripline, cascaded prism, Fabry-Perot etalon, and ring microresonator devices, have been fabricated and evaluated.

  3. Molecular Design of Benzodithiophene-Based Organic Photovoltaic Materials.

    PubMed

    Yao, Huifeng; Ye, Long; Zhang, Hao; Li, Sunsun; Zhang, Shaoqing; Hou, Jianhui

    2016-06-22

    Advances in the design and application of highly efficient conjugated polymers and small molecules over the past years have enabled the rapid progress in the development of organic photovoltaic (OPV) technology as a promising alternative to conventional solar cells. Among the numerous OPV materials, benzodithiophene (BDT)-based polymers and small molecules have come to the fore in achieving outstanding power conversion efficiency (PCE) and breaking 10% efficiency barrier in the single junction OPV devices. Remarkably, the OPV device featured by BDT-based polymer has recently demonstrated an impressive PCE of 11.21%, indicating the great potential of this class of materials in commercial photovoltaic applications. In this review, we offered an overview of the organic photovoltaic materials based on BDT from the aspects of backbones, functional groups, alkyl chains, and device performance, trying to provide a guideline about the structure-performance relationship. We believe more exciting BDT-based photovoltaic materials and devices will be developed in the near future. PMID:27251307

  4. Molecular Design of Benzodithiophene-Based Organic Photovoltaic Materials.

    PubMed

    Yao, Huifeng; Ye, Long; Zhang, Hao; Li, Sunsun; Zhang, Shaoqing; Hou, Jianhui

    2016-06-22

    Advances in the design and application of highly efficient conjugated polymers and small molecules over the past years have enabled the rapid progress in the development of organic photovoltaic (OPV) technology as a promising alternative to conventional solar cells. Among the numerous OPV materials, benzodithiophene (BDT)-based polymers and small molecules have come to the fore in achieving outstanding power conversion efficiency (PCE) and breaking 10% efficiency barrier in the single junction OPV devices. Remarkably, the OPV device featured by BDT-based polymer has recently demonstrated an impressive PCE of 11.21%, indicating the great potential of this class of materials in commercial photovoltaic applications. In this review, we offered an overview of the organic photovoltaic materials based on BDT from the aspects of backbones, functional groups, alkyl chains, and device performance, trying to provide a guideline about the structure-performance relationship. We believe more exciting BDT-based photovoltaic materials and devices will be developed in the near future.

  5. Testing and design life analysis of polyurea liner materials

    NASA Astrophysics Data System (ADS)

    Ghasemi Motlagh, Siavash

    Certainly, water pipes, as part of an underground infrastructure system, play a key role in maintaining quality of life, health, and wellbeing of human kind. As these potable water pipes reach the end of their useful life, they create high maintenance costs, loss of flow capacity, decreased water quality, and increased dissatisfaction. There are several different pipeline renewal techniques available for different applications, among which linings are most commonly used for the renewal of water pipes. Polyurea is a lining material applied to the interior surface of the deteriorated host pipe using spray-on technique. It is applied to structurally enhance the host pipe and provide a barrier coating against further corrosion or deterioration. The purpose of this study was to establish a relationship between stress, strain and time. The results obtained from these tests were used in predicting the strength of the polyurea material during its planned 50-year design life. In addition to this, based on the 10,000 hours experimental data, curve fitting and Findley power law models were employed to predict long-term behavior of the material. Experimental results indicated that the tested polyurea material offers a good balance of strength and stiffness and can be utilized in structural enhancement applications of potable water pipes.

  6. Designed amyloid fibers as materials for selective carbon dioxide capture

    PubMed Central

    Li, Dan; Furukawa, Hiroyasu; Deng, Hexiang; Liu, Cong; Yaghi, Omar M.; Eisenberg, David S.

    2014-01-01

    New materials capable of binding carbon dioxide are essential for addressing climate change. Here, we demonstrate that amyloids, self-assembling protein fibers, are effective for selective carbon dioxide capture. Solid-state NMR proves that amyloid fibers containing alkylamine groups reversibly bind carbon dioxide via carbamate formation. Thermodynamic and kinetic capture-and-release tests show the carbamate formation rate is fast enough to capture carbon dioxide by dynamic separation, undiminished by the presence of water, in both a natural amyloid and designed amyloids having increased carbon dioxide capacity. Heating to 100 °C regenerates the material. These results demonstrate the potential of amyloid fibers for environmental carbon dioxide capture. PMID:24367077

  7. Multiscale modeling for materials design: Molecular square catalysts

    NASA Astrophysics Data System (ADS)

    Majumder, Debarshi

    In a wide variety of materials, including a number of heterogeneous catalysts, the properties manifested at the process scale are a consequence of phenomena that occur at different time and length scales. Recent experimental developments allow materials to be designed precisely at the nanometer scale. However, the optimum design of such materials requires capabilities to predict the properties at the process scale based on the phenomena occurring at the relevant scales. The thesis research reported here addresses this need to develop multiscale modeling strategies for the design of new materials. As a model system, a new system of materials called molecular squares was studied in this research. Both serial and parallel multiscale strategies and their components were developed as parts of this work. As a serial component, a parameter estimation tool was developed that uses a hierarchical protocol and consists of two different search elements: a global search method implemented using a genetic algorithm that is capable of exploring large parametric space, and a local search method using gradient search techniques that accurately finds the optimum in a localized space. As an essential component of parallel multiscale modeling, different standard as well as specialized computational fluid dynamics (CFD) techniques were explored and developed in order to identify a technique that is best suited to solve a membrane reactor model employing layered films of molecular squares as the heterogeneous catalyst. The coupled set of non-linear partial differential equations (PDEs) representing the continuum model was solved numerically using three different classes of methods: a split-step method using finite difference (FD); domain decomposition in two different forms, one involving three overlapping subdomains and the other involving a gap-tooth scheme; and the multiple-timestep method that was developed in this research. The parallel multiscale approach coupled continuum

  8. Designing thin film materials — Ternary borides from first principles

    PubMed Central

    Euchner, H.; Mayrhofer, P.H.

    2015-01-01

    Exploiting the mechanisms responsible for the exceptional properties of aluminum based nitride coatings, we apply ab initio calculations to develop a recipe for designing functional thin film materials based on ternary diborides. The combination of binary diborides, preferring different structure types, results in supersaturated metastable ternary systems with potential for phase transformation induced effects. For the exemplary cases of MxW1 − xB2 (with M = Al, Ti, V) we show by detailed ab initio calculations that the respective ternary solid solutions are likely to be experimentally accessible by modern depositions techniques. PMID:26082562

  9. Hybrid materials science: a promised land for the integrative design of multifunctional materials

    NASA Astrophysics Data System (ADS)

    Nicole, Lionel; Laberty-Robert, Christel; Rozes, Laurence; Sanchez, Clément

    2014-05-01

    For more than 5000 years, organic-inorganic composite materials created by men via skill and serendipity have been part of human culture and customs. The concept of ``hybrid organic-inorganic'' nanocomposites exploded in the second half of the 20th century with the expansion of the so-called ``chimie douce'' which led to many collaborations between a large set of chemists, physicists and biologists. Consequently, the scientific melting pot of these very different scientific communities created a new pluridisciplinary school of thought. Today, the tremendous effort of basic research performed in the last twenty years allows tailor-made multifunctional hybrid materials with perfect control over composition, structure and shape. Some of these hybrid materials have already entered the industrial market. Many tailor-made multiscale hybrids are increasingly impacting numerous fields of applications: optics, catalysis, energy, environment, nanomedicine, etc. In the present feature article, we emphasize several fundamental and applied aspects of the hybrid materials field: bioreplication, mesostructured thin films, Lego-like chemistry designed hybrid nanocomposites, and advanced hybrid materials for energy. Finally, a few commercial applications of hybrid materials will be presented.

  10. Hybrid materials science: a promised land for the integrative design of multifunctional materials.

    PubMed

    Nicole, Lionel; Laberty-Robert, Christel; Rozes, Laurence; Sanchez, Clément

    2014-06-21

    For more than 5000 years, organic-inorganic composite materials created by men via skill and serendipity have been part of human culture and customs. The concept of "hybrid organic-inorganic" nanocomposites exploded in the second half of the 20th century with the expansion of the so-called "chimie douce" which led to many collaborations between a large set of chemists, physicists and biologists. Consequently, the scientific melting pot of these very different scientific communities created a new pluridisciplinary school of thought. Today, the tremendous effort of basic research performed in the last twenty years allows tailor-made multifunctional hybrid materials with perfect control over composition, structure and shape. Some of these hybrid materials have already entered the industrial market. Many tailor-made multiscale hybrids are increasingly impacting numerous fields of applications: optics, catalysis, energy, environment, nanomedicine, etc. In the present feature article, we emphasize several fundamental and applied aspects of the hybrid materials field: bioreplication, mesostructured thin films, Lego-like chemistry designed hybrid nanocomposites, and advanced hybrid materials for energy. Finally, a few commercial applications of hybrid materials will be presented. PMID:24866174

  11. Hybrid materials science: a promised land for the integrative design of multifunctional materials.

    PubMed

    Nicole, Lionel; Laberty-Robert, Christel; Rozes, Laurence; Sanchez, Clément

    2014-06-21

    For more than 5000 years, organic-inorganic composite materials created by men via skill and serendipity have been part of human culture and customs. The concept of "hybrid organic-inorganic" nanocomposites exploded in the second half of the 20th century with the expansion of the so-called "chimie douce" which led to many collaborations between a large set of chemists, physicists and biologists. Consequently, the scientific melting pot of these very different scientific communities created a new pluridisciplinary school of thought. Today, the tremendous effort of basic research performed in the last twenty years allows tailor-made multifunctional hybrid materials with perfect control over composition, structure and shape. Some of these hybrid materials have already entered the industrial market. Many tailor-made multiscale hybrids are increasingly impacting numerous fields of applications: optics, catalysis, energy, environment, nanomedicine, etc. In the present feature article, we emphasize several fundamental and applied aspects of the hybrid materials field: bioreplication, mesostructured thin films, Lego-like chemistry designed hybrid nanocomposites, and advanced hybrid materials for energy. Finally, a few commercial applications of hybrid materials will be presented.

  12. ATRP in the design of functional materials for biomedical applications

    PubMed Central

    Siegwart, Daniel J.; Oh, Jung Kwon; Matyjaszewski, Krzysztof

    2013-01-01

    Atom Transfer Radical Polymerization (ATRP) is an effective technique for the design and preparation of multifunctional, nanostructured materials for a variety of applications in biology and medicine. ATRP enables precise control over macromolecular structure, order, and functionality, which are important considerations for emerging biomedical designs. This article reviews recent advances in the preparation of polymer-based nanomaterials using ATRP, including polymer bioconjugates, block copolymer-based drug delivery systems, cross-linked microgels/nanogels, diagnostic and imaging platforms, tissue engineering hydrogels, and degradable polymers. It is envisioned that precise engineering at the molecular level will translate to tailored macroscopic physical properties, thus enabling control of the key elements for realized biomedical applications. PMID:23525884

  13. Taguchi method of experimental design in materials education

    NASA Technical Reports Server (NTRS)

    Weiser, Martin W.

    1993-01-01

    Some of the advantages and disadvantages of the Taguchi Method of experimental design as applied to Materials Science will be discussed. This is a fractional factorial method that employs the minimum number of experimental trials for the information obtained. The analysis is also very simple to use and teach, which is quite advantageous in the classroom. In addition, the Taguchi loss function can be easily incorporated to emphasize that improvements in reproducibility are often at least as important as optimization of the response. The disadvantages of the Taguchi Method include the fact that factor interactions are normally not accounted for, there are zero degrees of freedom if all of the possible factors are used, and randomization is normally not used to prevent environmental biasing. In spite of these disadvantages it is felt that the Taguchi Method is extremely useful for both teaching experimental design and as a research tool, as will be shown with a number of brief examples.

  14. Advances in design and modeling of porous materials

    NASA Astrophysics Data System (ADS)

    Ayral, André; Calas-Etienne, Sylvie; Coasne, Benoit; Deratani, André; Evstratov, Alexis; Galarneau, Anne; Grande, Daniel; Hureau, Matthieu; Jobic, Hervé; Morlay, Catherine; Parmentier, Julien; Prelot, Bénédicte; Rossignol, Sylvie; Simon-Masseron, Angélique; Thibault-Starzyk, Frédéric

    2015-07-01

    This special issue of the European Physical Journal Special Topics is dedicated to selected papers from the symposium "High surface area porous and granular materials" organized in the frame of the conference "Matériaux 2014", held on November 24-28, 2014 in Montpellier, France. Porous materials and granular materials gather a wide variety of heterogeneous, isotropic or anisotropic media made of inorganic, organic or hybrid solid skeletons, with open or closed porosity, and pore sizes ranging from the centimeter scale to the sub-nanometer scale. Their technological and industrial applications cover numerous areas from building and civil engineering to microelectronics, including also metallurgy, chemistry, health, waste water and gas effluent treatment. Many emerging processes related to environmental protection and sustainable development also rely on this class of materials. Their functional properties are related to specific transfer mechanisms (matter, heat, radiation, electrical charge), to pore surface chemistry (exchange, adsorption, heterogeneous catalysis) and to retention inside confined volumes (storage, separation, exchange, controlled release). The development of innovative synthesis, shaping, characterization and modeling approaches enables the design of advanced materials with enhanced functional performance. The papers collected in this special issue offer a good overview of the state-of-the-art and science of these complex media. We would like to thank all the speakers and participants for their contribution to the success of the symposium. We also express our gratitude to the organization committee of "Matériaux 2014". We finally thank the reviewers and the staff of the European Physical Journal Special Topics who made the publication of this special issue possible.

  15. From molecular design and materials construction to organic nanophotonic devices.

    PubMed

    Zhang, Chuang; Yan, Yongli; Zhao, Yong Sheng; Yao, Jiannian

    2014-12-16

    CONSPECTUS: Nanophotonics has recently received broad research interest, since it may provide an alternative opportunity to overcome the fundamental limitations in electronic circuits. Diverse optical materials down to the wavelength scale are required to develop nanophotonic devices, including functional components for light emission, transmission, and detection. During the past decade, the chemists have made their own contributions to this interdisciplinary field, especially from the controlled fabrication of nanophotonic molecules and materials. In this context, organic micro- or nanocrystals have been developed as a very promising kind of building block in the construction of novel units for integrated nanophotonics, mainly due to the great versatility in organic molecular structures and their flexibility for the subsequent processing. Following the pioneering works on organic nanolasers and optical waveguides, the organic nanophotonic materials and devices have attracted increasing interest and developed rapidly during the past few years. In this Account, we review our research on the photonic performance of molecular micro- or nanostructures and the latest breakthroughs toward organic nanophotonic devices. Overall, the versatile features of organic materials are highlighted, because they brings tunable optical properties based on molecular design, size-dependent light confinement in low-dimensional structures, and various device geometries for nanophotonic integration. The molecular diversity enables abundant optical transitions in conjugated π-electron systems, and thus brings specific photonic functions into molecular aggregates. The morphology of these micro- or nanostructures can be further controlled based on the weak intermolecular interactions during molecular assembly process, making the aggregates show photon confinement or light guiding properties as nanophotonic materials. By adoption of some active processes in the composite of two or more

  16. From molecular design and materials construction to organic nanophotonic devices.

    PubMed

    Zhang, Chuang; Yan, Yongli; Zhao, Yong Sheng; Yao, Jiannian

    2014-12-16

    CONSPECTUS: Nanophotonics has recently received broad research interest, since it may provide an alternative opportunity to overcome the fundamental limitations in electronic circuits. Diverse optical materials down to the wavelength scale are required to develop nanophotonic devices, including functional components for light emission, transmission, and detection. During the past decade, the chemists have made their own contributions to this interdisciplinary field, especially from the controlled fabrication of nanophotonic molecules and materials. In this context, organic micro- or nanocrystals have been developed as a very promising kind of building block in the construction of novel units for integrated nanophotonics, mainly due to the great versatility in organic molecular structures and their flexibility for the subsequent processing. Following the pioneering works on organic nanolasers and optical waveguides, the organic nanophotonic materials and devices have attracted increasing interest and developed rapidly during the past few years. In this Account, we review our research on the photonic performance of molecular micro- or nanostructures and the latest breakthroughs toward organic nanophotonic devices. Overall, the versatile features of organic materials are highlighted, because they brings tunable optical properties based on molecular design, size-dependent light confinement in low-dimensional structures, and various device geometries for nanophotonic integration. The molecular diversity enables abundant optical transitions in conjugated π-electron systems, and thus brings specific photonic functions into molecular aggregates. The morphology of these micro- or nanostructures can be further controlled based on the weak intermolecular interactions during molecular assembly process, making the aggregates show photon confinement or light guiding properties as nanophotonic materials. By adoption of some active processes in the composite of two or more

  17. Materials Design for Joinable, High Performance Aluminum Alloys

    NASA Astrophysics Data System (ADS)

    Glamm, Ryan James

    An aluminum alloy compatible with friction stir welding is designed for automotive and aerospace structural applications. Current weldable automotive aluminum alloys do not possess the necessary strength to meet safety standards and therefore are not able to replace steel in the automotive body. Significant weight savings could be achieved if steel components are replaced with aluminum. Current aerospace alloys are not weldable, requiring machining of large pieces that are then riveted together. If an aerospace alloy could be friction stir welded, smaller pieces could be welded, reducing material waste. Using a systems approach for materials design, property goals are set from performance objectives. From previous research and computational predictions, a structure is designed for a prototype alloy containing dynamic precipitates to readily dissolve and re-precipitate and high stability precipitates to resist dissolution and coarsening in the weld region. It is found that a Ag modified Al-3.9Mg-0.04Cu (at. %) alloy enhanced the rate and magnitude of hardening during ageing, both beneficial effects for dynamic precipitation. In the same alloy, ageing at 350°C results in hardening from Al 3(Sc,Zr) precipitates. Efforts to effectively precipitate both populations simultaneously are unsuccessful. The Al3(Sc,Zr) precipitation hardened prototype is friction stir processed and no weak zones are found in the weld hardness profile. An aerospace alloy design is proposed, utilizing the dual precipitate structure shown in the prototype. The automotive alloy is designed using a basic strength model with parameters determined from the initial prototype alloy analysis. After ageing to different conditions, the alloy is put through a simulated heat affected zone thermal cycle with a computer controlled induction heater. The aged samples lose hardness from the weld cycle but recover hardness from a post weld heat treatment. Atom probe tomography and transmission electron

  18. 14 CFR 29.613 - Material strength properties and design values.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Material strength properties and design... § 29.613 Material strength properties and design values. (a) Material strength properties must be based on enough tests of material meeting specifications to establish design values on a statistical...

  19. 14 CFR 27.613 - Material strength properties and design values.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Material strength properties and design....613 Material strength properties and design values. (a) Material strength properties must be based on enough tests of material meeting specifications to establish design values on a statistical basis....

  20. 14 CFR 29.613 - Material strength properties and design values.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Material strength properties and design... § 29.613 Material strength properties and design values. (a) Material strength properties must be based on enough tests of material meeting specifications to establish design values on a statistical...

  1. 14 CFR 27.613 - Material strength properties and design values.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Material strength properties and design....613 Material strength properties and design values. (a) Material strength properties must be based on enough tests of material meeting specifications to establish design values on a statistical basis....

  2. 14 CFR 29.613 - Material strength properties and design values.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Material strength properties and design... § 29.613 Material strength properties and design values. (a) Material strength properties must be based on enough tests of material meeting specifications to establish design values on a statistical...

  3. 14 CFR 29.613 - Material strength properties and design values.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Material strength properties and design... § 29.613 Material strength properties and design values. (a) Material strength properties must be based on enough tests of material meeting specifications to establish design values on a statistical...

  4. 14 CFR 27.613 - Material strength properties and design values.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Material strength properties and design....613 Material strength properties and design values. (a) Material strength properties must be based on enough tests of material meeting specifications to establish design values on a statistical basis....

  5. 14 CFR 27.613 - Material strength properties and design values.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Material strength properties and design....613 Material strength properties and design values. (a) Material strength properties must be based on enough tests of material meeting specifications to establish design values on a statistical basis....

  6. Evolutionary design of bone scaffolds with reference to material selection.

    PubMed

    Heljak, M K; Swięszkowski, W; Lam, C X F; Hutmacher, D W; Kurzydłowski, K J

    2012-01-01

    The favourable scaffold for bone tissue engineering should have desired characteristic features, such as adequate mechanical strength and three-dimensional open porosity, which guarantee a suitable environment for tissue regeneration. In fact, the design of such complex structures like bone scaffolds is a challenge for investigators. One of the aims is to achieve the best possible mechanical strength-degradation rate ratio. In this paper we attempt to use numerical modelling to evaluate material properties for designing bone tissue engineering scaffold fabricated via the fused deposition modelling technique. For our studies the standard genetic algorithm was used, which is an efficient method of discrete optimization. For the fused deposition modelling scaffold, each individual strut is scrutinized for its role in the architecture and structural support it provides for the scaffold, and its contribution to the overall scaffold was studied. The goal of the study was to create a numerical tool that could help to acquire the desired behaviour of tissue engineered scaffolds and our results showed that this could be achieved efficiently by using different materials for individual struts. To represent a great number of ways in which scaffold mechanical function loss could proceed, the exemplary set of different desirable scaffold stiffness loss function was chosen.

  7. Computational design of surfaces, nanostructures and optoelectronic materials

    NASA Astrophysics Data System (ADS)

    Choudhary, Kamal

    Properties of engineering materials are generally influenced by defects such as point defects (vacancies, interstitials, substitutional defects), line defects (dislocations), planar defects (grain boundaries, free surfaces/nanostructures, interfaces, stacking faults) and volume defects (voids). Classical physics based molecular dynamics and quantum physics based density functional theory can be useful in designing materials with controlled defect properties. In this thesis, empirical potential based molecular dynamics was used to study the surface modification of polymers due to energetic polyatomic ion, thermodynamics and mechanics of metal-ceramic interfaces and nanostructures, while density functional theory was used to screen substituents in optoelectronic materials. Firstly, polyatomic ion-beams were deposited on polymer surfaces and the resulting chemical modifications of the surface were examined. In particular, S, SC and SH were deposited on amorphous polystyrene (PS), and C2H, CH3, and C3H5 were deposited on amorphous poly (methyl methacrylate) (PMMA) using molecular dynamics simulations with classical reactive empirical many-body (REBO) potentials. The objective of this work was to elucidate the mechanisms by which the polymer surface modification took place. The results of the work could be used in tailoring the incident energy and/or constituents of ion beam for obtaining a particular chemistry inside the polymer surface. Secondly, a new Al-O-N empirical potential was developed within the charge optimized many body (COMB) formalism. This potential was then used to examine the thermodynamic stability of interfaces and mechanical properties of nanostructures composed of aluminum, its oxide and its nitride. The potentials were tested for these materials based on surface energies, defect energies, bulk phase stability, the mechanical properties of the most stable bulk phase, its phonon properties as well as with a genetic algorithm based evolution theory of

  8. Failure modes and materials design for biomechanical layer structures

    NASA Astrophysics Data System (ADS)

    Deng, Yan

    ) and strength (400--1400MPa): Y-TZP zirconia, InCeram alumina and Empress II glass-ceramic. Explicit relations for the critical loads P to produce these different damage modes in bilayer and trilayer structures are developed in terms of basic material properties (modulus E, strength, hardness H and toughness T) and geometrical variables (thickness d and contact sphere radius r). These experimentally validated relations are used to design of optimal material combinations for improved fracture resistance and to predict mechanical performance of current dental materials.

  9. Harvesting bioenergy with rationally designed complex functional materials

    NASA Astrophysics Data System (ADS)

    Kuang, Liangju

    A key challenge in renewable energy is to capture, convert and store solar power with earth-abundant materials and environmentally benign technologies. The goal of this thesis is to develop rationally designed complex functional materials for bio-renewable energy applications. On one hand, photoconversion membrane proteins (MPs) are nature's nanoengineering feats for renewable energy management. Harnessing their functions in synthetic systems could help understand, predict, and ultimately control matter and energy at the nanoscale. This is particularly enticing in the post-genome era as recombinant or cell-free expression of many MPs with high yields becomes possible. However, the labile nature of lipid bilayers renders them unsuitable for use in a broad range of engineered systems. A knowledge gap exists about how to design robust synthetic nanomembranes as lipid-bilayer-mimics to support MP functions and how to direct hierarchical MP reconstitution into those membranes to form 2-D or 3-D ordered proteomembrane arrays. Our studies on proteorhodopsin (PR) and bacterial reaction center (BRC), the two light-harvesting MPs, reveal that a charge-interaction-directed reconstitution (CIDR) mechanism induces spontaneous reconstitution of detergent-solubilized MPs into various amphiphilic block copolymer membranes, many of which have far superior stability than lipid bilayers. Our preliminary data also suggest MPs are not enslaved by the biological membranes they derive from; rather, the chemically nonspecific material properties of MP-supporting membranes may act as allosteric regulators. Versatile chemical designs are possible to modulate the conformational energetics of MPs, hence their transport performance in synthetic systems. On the other hand, microalgae are widely regarded as a sustainable feedstock for biofuel production. Microalgae-derived biofuels have not been commercialized yet because current technologies for microalgae dewatering add a huge cost to the

  10. Optimal Design of Honeycomb Material Used to Mitigate Head Impact

    PubMed Central

    Caccese, Vincent; Ferguson, James R.; Edgecomb, Michael

    2013-01-01

    This paper presents a study of the impact resistance of honeycomb structure with the purpose to mitigate impact forces. The objective is to aid in the choice of optimal parameters to minimize the thickness of the honeycomb structure while providing adequate protection to prevent injury due to head impact. Studies are presented using explicit finite element analysis representing the case of an unprotected drop of a rigid impactor onto a simulated floor consisting of vinyl composition tile and concrete. Analysis of honeycomb material to reduce resulting accelerations is also presented where parameters such as honeycomb material modulus, wall thickness, cell geometry and structure depth are compared to the unprotected case. A simplified analysis technique using a genetic algorithm is presented to demonstrate the use of this method to select a minimum honeycomb depth to achieve a desired acceleration level at a given level of input energy. It is important to select a minimum material depth in that smaller dimensions lead toward more aesthetic design that increase the likelihood of that the device is used. PMID:23976812

  11. Micro-/nanostructured multicomponent molecular materials: design, assembly, and functionality.

    PubMed

    Yan, Dongpeng

    2015-03-23

    Molecule-based micro-/nanomaterials have attracted considerable attention because their properties can vary greatly from the corresponding macro-sized bulk systems. Recently, the construction of multicomponent molecular solids based on crystal engineering principles has emerged as a promising alternative way to develop micro-/nanomaterials. Unlike single-component materials, the resulting multicomponent systems offer the advantages of tunable composition, and adjustable molecular arrangement, and intermolecular interactions within their solid states. The study of these materials also supplies insight into how the crystal structure, molecular components, and micro-/nanoscale effects can influence the performance of molecular materials. In this review, we describe recent advances and current directions in the assembly and applications of crystalline multicomponent micro-/nanostructures. Firstly, the design strategies for multicomponent systems based on molecular recognition and crystal engineering principles are introduced. Attention is then focused on the methods of fabrication of low-dimensional multicomponent micro-/nanostructures. Their new applications are also outlined. Finally, we briefly discuss perspectives for the further development of these molecular crystalline micro-/nanomaterials.

  12. Materials for Consideration in Standardized Canister Design Activities.

    SciTech Connect

    Bryan, Charles R.; Ilgen, Anastasia Gennadyevna; Enos, David George; Teich-McGoldrick, Stephanie; Hardin, Ernest

    2014-10-01

    This document identifies materials and material mitigation processes that might be used in new designs for standardized canisters for storage, transportation, and disposal of spent nuclear fuel. It also addresses potential corrosion issues with existing dual-purpose canisters (DPCs) that could be addressed in new canister designs. The major potential corrosion risk during storage is stress corrosion cracking of the weld regions on the 304 SS/316 SS canister shell due to deliquescence of chloride salts on the surface. Two approaches are proposed to alleviate this potential risk. First, the existing canister materials (304 and 316 SS) could be used, but the welds mitigated to relieve residual stresses and/or sensitization. Alternatively, more corrosion-resistant steels such as super-austenitic or duplex stainless steels, could be used. Experimental testing is needed to verify that these alternatives would successfully reduce the risk of stress corrosion cracking during fuel storage. For disposal in a geologic repository, the canister will be enclosed in a corrosion-resistant or corrosion-allowance overpack that will provide barrier capability and mechanical strength. The canister shell will no longer have a barrier function and its containment integrity can be ignored. The basket and neutron absorbers within the canister have the important role of limiting the possibility of post-closure criticality. The time period for corrosion is much longer in the post-closure period, and one major unanswered question is whether the basket materials will corrode slowly enough to maintain structural integrity for at least 10,000 years. Whereas there is extensive literature on stainless steels, this evaluation recommends testing of 304 and 316 SS, and more corrosion-resistant steels such as super-austenitic, duplex, and super-duplex stainless steels, at repository-relevant physical and chemical conditions. Both general and localized corrosion testing methods would be used to

  13. Process design of press hardening with gradient material property influence

    SciTech Connect

    Neugebauer, R.; Schieck, F.; Rautenstrauch, A.

    2011-05-04

    Press hardening is currently used in the production of automotive structures that require very high strength and controlled deformation during crash tests. Press hardening can achieve significant reductions of sheet thickness at constant strength and is therefore a promising technology for the production of lightweight and energy-efficient automobiles. The manganese-boron steel 22MnB5 have been implemented in sheet press hardening owing to their excellent hot formability, high hardenability, and good temperability even at low cooling rates. However, press-hardened components have shown poor ductility and cracking at relatively small strains. A possible solution to this problem is a selective increase of steel sheet ductility by press hardening process design in areas where the component is required to deform plastically during crash tests. To this end, process designers require information about microstructure and mechanical properties as a function of the wide spectrum of cooling rates and sequences and austenitizing treatment conditions that can be encountered in production environments. In the present work, a Continuous Cooling Transformation (CCT) diagram with corresponding material properties of sheet steel 22MnB5 was determined for a wide spectrum of cooling rates. Heating and cooling programs were conducted in a quenching dilatometer. Motivated by the importance of residual elasticity in crash test performance, this property was measured using a micro-bending test and the results were integrated into the CCT diagrams to complement the hardness testing results. This information is essential for the process design of press hardening of sheet components with gradient material properties.

  14. Interfacing materials science and biology for drug carrier design.

    PubMed

    Such, Georgina K; Yan, Yan; Johnston, Angus P R; Gunawan, Sylvia T; Caruso, Frank

    2015-04-01

    Over the last ten years, there has been considerable research interest in the development of polymeric carriers for biomedicine. Such delivery systems have the potential to significantly reduce side effects and increase the bioavailability of poorly soluble therapeutics. The design of carriers has relied on harnessing specific variations in biological conditions, such as pH or redox potential, and more recently, by incorporating specific peptide cleavage sites for enzymatic hydrolysis. Although much progress has been made in this field, the specificity of polymeric carriers is still limited when compared with their biological counterparts. To synthesize the next generation of carriers, it is important to consider the biological rationale for materials design. This requires a detailed understanding of the cellular microenvironments and how these can be harnessed for specific applications. In this review, several important physiological cues in the cellular microenvironments are outlined, with a focus on changes in pH, redox potential, and the types of enzymes present in specific regions. Furthermore, recent studies that use such biologically inspired triggers to design polymeric carriers are highlighted, focusing on applications in the field of therapeutic delivery.

  15. A new design concept for multifunctional fasteners using smart materials

    NASA Astrophysics Data System (ADS)

    Yoon, Hwan-Sik

    2009-03-01

    In this paper, a new design concept for multifunctional fasteners using smart materials is presented. The proposed piezoelectric devices, named 'smart fasteners,' can be fabricated by modifying the design of ordinary fasteners such that they have a piezoelectric element and a control unit embedded in their body. These smart fasteners can not only clamp structural members like ordinary fasteners but also measure the response of the structure and generate forces to enhance the dynamic performance of the structure. Due to their fastener-type design, they are more convenient to install onto or remove from structures compared to conventional piezoceramic patch actuators for which a bonding epoxy layer needs to be applied. In order to demonstrate their applicability in active vibration controls, a simulation study was conducted on a fixed-fixed beam structure. Since the control force is applied at the boundary of the structure where the smart fasteners are attached, a new control algorithm called Active Boundary Control (ABC) was developed using the Lyapunov's direct method. The simulation results show that smart fasteners can be used to suppress vibration of the beam by applying the Lyapunov-based Active Boundary Control algorithm.

  16. Design of Functional Materials with Hydrogen-Bonded Host Frameworks

    NASA Astrophysics Data System (ADS)

    Soegiarto, Airon Cosanova

    The properties of molecular crystals are governed by the attributes of their molecular constituents and their solid-state arrangements, making control of crystal packing paramount when designing new materials with targeted functions. One effective strategy involves the use of robust host frameworks that encapsulate functional guests in molecular-scale cavities with tailored shapes, sizes, and chemical environments that enable systematic regulation of solid state properties. This approach promises to simplify the synthesis of molecular materials by decoupling the design of structure, provided by the host framework, from function, introduced by the guests. This thesis has reported a series of crystalline, structurally robust hosts based on guanidinium cations (G = (C(NH2) 3 +) and the sulfonate moieties of organodisulfonate anions (DS; S = -O3S-R-SO3 -). The host framework is based on layers of 2-D GS sheet, which are interconnected by the organic residues (pillars) of the disulfonates, thereby producing a lamellar architecture with inclusion cavities, occupied by guest molecules, between the sheets. Notably, the GDS inclusion compounds exhibit numerous architectures such as bilayer, simple brick, and zigzag brick -- each endowed with uniquely sized and shaped cavities, suggesting that the aggregation motifs of the included guests can be controlled within the host lattice. Furthermore, the selectivity toward different architectures is governed by the relative size of the pillars and guests, allowing the construction of a "structural phase diagram" which can be used to predict the solid-state architecture of untested host-guest combination. Consequently, a variety of functional molecules have been included in order to exploit these features. Chapter 3 reports the inclusion of polyconjugated molecules within the GDS hosts, generating various guest aggregation motifs -- edge-to-edge to face-to-edge to end-to-end. The effects of the various host and/or guest aggregation

  17. Harnessing the Big Data Paradigm for ICME: Shifting from Materials Selection to Materials Enabled Design

    NASA Astrophysics Data System (ADS)

    Broderick, Scott R.; Santhanam, Ganesh Ram; Rajan, Krishna

    2016-08-01

    As the size of databases has significantly increased, whether through high throughput computation or through informatics-based modeling, the challenge of selecting the optimal material for specific design requirements has also arisen. Given the multiple, and often conflicting, design requirements, this selection process is not as trivial as sorting the database for a given property value. We suggest that the materials selection process should minimize selector bias, as well as take data uncertainty into account. For this reason, we discuss and apply decision theory for identifying chemical additions to Ni-base alloys. We demonstrate and compare results for both a computational array of chemistries and standard commercial superalloys. We demonstrate how we can use decision theory to select the best chemical additions for enhancing both property and processing, which would not otherwise be easily identifiable. This work is one of the first examples of introducing the mathematical framework of set theory and decision analysis into the domain of the materials selection process.

  18. Harnessing the Big Data Paradigm for ICME: Shifting from Materials Selection to Materials Enabled Design

    NASA Astrophysics Data System (ADS)

    Broderick, Scott R.; Santhanam, Ganesh Ram; Rajan, Krishna

    2016-07-01

    As the size of databases has significantly increased, whether through high throughput computation or through informatics-based modeling, the challenge of selecting the optimal material for specific design requirements has also arisen. Given the multiple, and often conflicting, design requirements, this selection process is not as trivial as sorting the database for a given property value. We suggest that the materials selection process should minimize selector bias, as well as take data uncertainty into account. For this reason, we discuss and apply decision theory for identifying chemical additions to Ni-base alloys. We demonstrate and compare results for both a computational array of chemistries and standard commercial superalloys. We demonstrate how we can use decision theory to select the best chemical additions for enhancing both property and processing, which would not otherwise be easily identifiable. This work is one of the first examples of introducing the mathematical framework of set theory and decision analysis into the domain of the materials selection process.

  19. Interfacial Properties and Design of Functional Energy Materials

    SciTech Connect

    Sumpter, Bobby G; Liang, Liangbo; Nicolai, Adrien; Meunier, V.

    2014-01-01

    The vital importance of energy to society continues to demand a relentless pursuit of energy responsive materials that can bridge fundamental chemical structures at the molecular level and achieve improved functionality, such as efficient energy conversion/storage/transmission, over multiple length scales. This demand can potentially be realized by harnessing the power of self-assembly a spontaneous process where molecules or much larger entities form ordered aggregates as a consequence of predominately non-covalent (weak) interactions. Self-assembly is the key to bottom-up design of molecular devices, because the nearly atomic-level control is very difficult to realize in a top-down, e.g., lithographic approach. However, while function (e.g., charge mobility) in simple systems such as single crystals can often be predicted, predicting the function of the great variety of self-assembled molecular architectures is complicated by the lack of understanding and control over nanoscale interactions, mesoscale architectures, and macroscale (long-range) order. To establish a foundation toward delivering practical solutions, it is critical to develop an understanding of the chemical and physical mechanisms responsible for the self-assembly of molecular and hybrid materials on various substrates. Typically molecular self-assembly involves poorly understood non-covalent intermolecular and substrate-molecule interactions compounded by local and/or collective influences from the substrate atomic lattice (symmetry and/or topological features) and electronic structure. Thus, progress towards unraveling the underlying physicochemical processes that control the structure and macroscopic physical, mechanical, electrical, and transport properties of materials increasingly requires tight integration of theory, modeling and simulation with precision synthesis, advanced experimental characterization, and device measurements. In this mode, theory and simulation can greatly accelerate the

  20. Design, fabrication and fundamental studies of plasmonic materials

    NASA Astrophysics Data System (ADS)

    McLellan, Erin C.

    2007-12-01

    Nanoplasmonics is an emerging branch of photonics that studies the optical properties of noble metals. Nanostructured noble metal materials, which can strongly interact with light and support various plasmon modes, are exceptional candidates for nanophotonic devices. This work describes the latest advances in the fabrication of ordered silver nanoparticles or nanowell arrays using both nanosphere lithography (NSL) and electron beam lithography (EBL). More specifically, three types of new NSL-derived materials are addressed in this thesis: (1) the application of electrochemistry to "fine tune" the structure of silver nanotriangles and the wavelength of their localized surface plasmon resonance (LSPR), (2) the fabrication of ordered arrays of in-plane, triangular cross-section nanowells with the aid of reactive ion etching (RIE), and (3) the anchoring of the truncated tetrahedrons for a more stabile sensing surface. Futhermore, utilizing EBL, studies looking deeper into the fundamental coupling interactions in both one and two dimensional arrays were performed. All of these studies will allow for the logical design of novel plasmonic devices for an array of applications.

  1. Designing functionally graded materials with superior load-bearing properties.

    PubMed

    Zhang, Yu; Sun, Ming-Jie; Zhang, Denzil

    2012-03-01

    Ceramic prostheses often fail from fracture and wear. We hypothesize that these failures may be substantially mitigated by an appropriate grading of elastic modulus at the ceramic surface. In this study, we elucidate the effect of elastic modulus profile on the flexural damage resistance of functionally graded materials (FGMs), providing theoretical guidelines for designing FGMs with superior load-bearing property. The Young's modulus of the graded structure is assumed to vary in a power-law relation with a scaling exponent n; this is in accordance with experimental observations from our laboratory and elsewhere. Based on the theory for bending of graded beams, we examine the effect of n value and bulk-to-surface modulus ratio (E(b)/E(s)) on stress distribution through the graded layer. Theory predicts that a low exponent (0.15materials with various n values and E(b)/E(s) ratios can be fabricated by infiltrating alumina and zirconia with a low-modulus glass. Flexural tests show that graded alumina and zirconia with suitable values of these parameters exhibit superior load-bearing capacity, 20-50% higher than their homogeneous counterparts. Improving load-bearing capacity of ceramic materials could have broad impacts on biomedical, civil, structural, and an array of other engineering applications.

  2. Mechanical design of mussel byssus: material yield enhances attachment strength

    PubMed

    Bell; Gosline

    1996-01-01

    The competitive dominance of mussels in the wave-swept rocky intertidal zone is in part due to their ability to maintain a secure attachment. Mussels are tethered to the substratum by a byssus composed of numerous extracellular, collagenous threads secreted by the foot. Each byssal thread has three serially arranged parts: a corrugated proximal region, a smooth distal region and an adhesive plaque. This study examines the material and structural properties of the byssal threads of three mussel species: Mytilus californianus, M. trossulus, and M. galloprovincialis. Tensile tests in general reveal similar material properties among species: the proximal region has a lower initial modulus, a lower ultimate stress and a higher ultimate strain than the distal region. The distal region also yields at a stress well below its ultimate value. In whole thread tests, the proximal region and adhesive plaque are common sites of structural failure and are closely matched in strength, while the distal region appears to be excessively strong. We propose that the high strength of the distal region is the byproduct of a material designed to yield and extend before structural failure occurs. Experimental and theoretical evidence is presented suggesting that thread yield and extensibility provide two important mechanisms for increasing the overall attachment strength of the mussel: (1) the reorientation of threads towards the direction of applied load, and (2) the 'recruitment' of more threads into tension and the consequent distribution of applied load over a larger cross-sectional area, thereby reducing the stress on each thread. This distal region yield behavior is most striking for M. californianus and may be a key to its success in extreme wave-swept environments.

  3. EXPERIMENTAL STUDIES ON PARTICLE IMPACTION AND BOUNCE: EFFECTS OF SUBSTRATE DESIGN AND MATERIAL. (R825270)

    EPA Science Inventory

    This paper presents an experimental investigation of the effects of impaction substrate designs and material in reducing particle bounce and reentrainment. Particle collection without coating by using combinations of different impaction substrate designs and surface materials was...

  4. A domain-specific design architecture for composite material design and aircraft part redesign

    NASA Technical Reports Server (NTRS)

    Punch, W. F., III; Keller, K. J.; Bond, W.; Sticklen, J.

    1992-01-01

    Advanced composites have been targeted as a 'leapfrog' technology that would provide a unique global competitive position for U.S. industry. Composites are unique in the requirements for an integrated approach to designing, manufacturing, and marketing of products developed utilizing the new materials of construction. Numerous studies extending across the entire economic spectrum of the United States from aerospace to military to durable goods have identified composites as a 'key' technology. In general there have been two approaches to composite construction: build models of a given composite materials, then determine characteristics of the material via numerical simulation and empirical testing; and experience-directed construction of fabrication plans for building composites with given properties. The first route sets a goal to capture basic understanding of a device (the composite) by use of a rigorous mathematical model; the second attempts to capture the expertise about the process of fabricating a composite (to date) at a surface level typically expressed in a rule based system. From an AI perspective, these two research lines are attacking distinctly different problems, and both tracks have current limitations. The mathematical modeling approach has yielded a wealth of data but a large number of simplifying assumptions are needed to make numerical simulation tractable. Likewise, although surface level expertise about how to build a particular composite may yield important results, recent trends in the KBS area are towards augmenting surface level problem solving with deeper level knowledge. Many of the relative advantages of composites, e.g., the strength:weight ratio, is most prominent when the entire component is designed as a unitary piece. The bottleneck in undertaking such unitary design lies in the difficulty of the re-design task. Designing the fabrication protocols for a complex-shaped, thick section composite are currently very difficult. It is in

  5. Conceptual design report: Nuclear materials storage facility renovation. Part 1, Design concept. Part 2, Project management

    SciTech Connect

    1995-07-14

    The Nuclear Materials Storage Facility (NMSF) at the Los Alamos National Laboratory (LANL) was a Fiscal Year (FY) 1984 line-item project completed in 1987 that has never been operated because of major design and construction deficiencies. This renovation project, which will correct those deficiencies and allow operation of the facility, is proposed as an FY 97 line item. The mission of the project is to provide centralized intermediate and long-term storage of special nuclear materials (SNM) associated with defined LANL programmatic missions and to establish a centralized SNM shipping and receiving location for Technical Area (TA)-55 at LANL. Based on current projections, existing storage space for SNM at other locations at LANL will be loaded to capacity by approximately 2002. This will adversely affect LANUs ability to meet its mission requirements in the future. The affected missions include LANL`s weapons research, development, and testing (WRD&T) program; special materials recovery; stockpile survelliance/evaluation; advanced fuels and heat sources development and production; and safe, secure storage of existing nuclear materials inventories. The problem is further exacerbated by LANL`s inability to ship any materials offsite because of the lack of receiver sites for mate rial and regulatory issues. Correction of the current deficiencies and enhancement of the facility will provide centralized storage close to a nuclear materials processing facility. The project will enable long-term, cost-effective storage in a secure environment with reduced radiation exposure to workers, and eliminate potential exposures to the public. This document provides Part I - Design Concept which describes the selected solution, and Part II - Project Management which describes the management system organization, the elements that make up the system, and the control and reporting system.

  6. 46 CFR 160.170-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Davit..., or construction change. (a) Each change in design, material, or construction from the plans approved..., construction, and materials will be made by the Commandant only....

  7. 46 CFR 160.156-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... construction change. (a) Each change in design, material, or construction from the plans approved under 46 CFR... (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Rescue..., construction, and materials will be made by the Commandant only....

  8. 46 CFR 160.170-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Davit..., or construction change. (a) Each change in design, material, or construction from the plans approved..., construction, and materials will be made by the Commandant only....

  9. 46 CFR 160.156-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... construction change. (a) Each change in design, material, or construction from the plans approved under 46 CFR... (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Rescue..., construction, and materials will be made by the Commandant only....

  10. 46 CFR 160.133-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... construction change. (a) Each change in design, material, or construction from the plans approved under 46 CFR... (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Release..., material, or construction will be made by the Commandant only....

  11. 46 CFR 160.170-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Davit..., or construction change. (a) Each change in design, material, or construction from the plans approved..., construction, and materials will be made by the Commandant only....

  12. 46 CFR 160.133-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... construction change. (a) Each change in design, material, or construction from the plans approved under 46 CFR... (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Release..., material, or construction will be made by the Commandant only....

  13. 46 CFR 160.133-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... construction change. (a) Each change in design, material, or construction from the plans approved under 46 CFR... (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Release..., material, or construction will be made by the Commandant only....

  14. 46 CFR 160.156-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... construction change. (a) Each change in design, material, or construction from the plans approved under 46 CFR... (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Rescue..., construction, and materials will be made by the Commandant only....

  15. Design, synthesis, and evaluation of materials for microelectronics applications

    NASA Astrophysics Data System (ADS)

    Heath, William Hoy

    The advancement of the microelectronics industry is heavily dependent on the design, synthesis, and integration of new materials. Non-chemically amplified photoresists (NCAR) consist of a base resin and photoactive additive which inhibits the dissolution of the this resin. The robustness of NCARs has made them well suited to the unique material requirements of the photomask making industry for many years. However, smaller feature sizes now require mask makers to move to shorter wavelengths of light and thus a more transparent polymer and photoactive compound are needed for these applications. During the search for 157nm photoresists, it was found that polymers containing the hexafluoroisopropanol functionality are transparent well into the ultraviolet region and possess dissolution characteristics similar to the Novolak resins utilized in NCARs. A suitable photoactive compound (PAC) has been identified; the synthesis of the PAC and transparent polymers, as well as their formulation, dissolution properties, and lithographic evaluation will be presented. Additionally, the base catalyzed imidization of poly(amic acid ethyl ester) (PAETE) provides a good tool for developing a photosensitive polyimide insulator. However few base photogenerators (PBG) exist that absorb at the appropriate wavelength (>400nm) for use in these opaque films. Two sensitized systems were evaluated; their synthesis, photophysical evaluation, and attempted imaging in PAETE will be described. Additionally, the synthesis and photophysical evaluation of a red-shifted thiophene-based PBG will be described. Finally, step and flash imprint lithography exhibits a great promise as a cost effective alternative imaging solution to traditional optical lithography. A strippable resist is needed to preserve the templates used in this process should they become contaminated. The thermal reversibility of urethanes, specifically those derived from aromatic oximes, make them well suited for integration into a

  16. Eutectics as improved pharmaceutical materials: design, properties and characterization.

    PubMed

    Cherukuvada, Suryanarayan; Nangia, Ashwini

    2014-01-28

    Eutectics are a long known class of multi-component solids with important and useful applications in daily life. In comparison to other multi-component crystalline solids, such as salts, solid solutions, molecular complexes and cocrystals, eutectics are less studied in terms of molecular structure organization and bonding interactions. Classically, a eutectic is defined based on its low melting point compared to the individual components. In this article, we attempt to define eutectics not just based on thermal methods but from a structural organization view point, and discuss their microstructures and properties as organic materials vis-a-vis solid solutions and cocrystals. The X-ray crystal structure of a cocrystal is different from that of the individual components whereas the unit cell of a solid solution is similar to that of one of the components. Eutectics are closer to the latter species in that their crystalline arrangement is similar to the parent components but they are different with respect to the structural integrity. A solid solution possesses structural homogeneity throughout the structure (single phase) but a eutectic is a heterogeneous ensemble of individual components whose crystal structures are like discontinuous solid solutions (phase separated). Thus, a eutectic may be better defined as a conglomerate of solid solutions. A structural analysis of cocrystals, solid solutions and eutectics has led to an understanding that materials with strong adhesive (hetero) interactions between the unlike components will lead to cocrystals whereas those having stronger cohesive (homo/self) interactions will more often give rise to solid solutions (for similar structures of components) and eutectics (for different structures of components). We demonstrate that the same crystal engineering principles which have been profitably utilized for cocrystal design in the past decade can now be applied to make eutectics as novel composite materials, illustrated by

  17. Accelerated search for materials with targeted properties by adaptive design

    PubMed Central

    Xue, Dezhen; Balachandran, Prasanna V.; Hogden, John; Theiler, James; Xue, Deqing; Lookman, Turab

    2016-01-01

    Finding new materials with targeted properties has traditionally been guided by intuition, and trial and error. With increasing chemical complexity, the combinatorial possibilities are too large for an Edisonian approach to be practical. Here we show how an adaptive design strategy, tightly coupled with experiments, can accelerate the discovery process by sequentially identifying the next experiments or calculations, to effectively navigate the complex search space. Our strategy uses inference and global optimization to balance the trade-off between exploitation and exploration of the search space. We demonstrate this by finding very low thermal hysteresis (ΔT) NiTi-based shape memory alloys, with Ti50.0Ni46.7Cu0.8Fe2.3Pd0.2 possessing the smallest ΔT (1.84 K). We synthesize and characterize 36 predicted compositions (9 feedback loops) from a potential space of ∼800,000 compositions. Of these, 14 had smaller ΔT than any of the 22 in the original data set. PMID:27079901

  18. Accelerated search for materials with targeted properties by adaptive design

    NASA Astrophysics Data System (ADS)

    Xue, Dezhen; Balachandran, Prasanna V.; Hogden, John; Theiler, James; Xue, Deqing; Lookman, Turab

    2016-04-01

    Finding new materials with targeted properties has traditionally been guided by intuition, and trial and error. With increasing chemical complexity, the combinatorial possibilities are too large for an Edisonian approach to be practical. Here we show how an adaptive design strategy, tightly coupled with experiments, can accelerate the discovery process by sequentially identifying the next experiments or calculations, to effectively navigate the complex search space. Our strategy uses inference and global optimization to balance the trade-off between exploitation and exploration of the search space. We demonstrate this by finding very low thermal hysteresis (ΔT) NiTi-based shape memory alloys, with Ti50.0Ni46.7Cu0.8Fe2.3Pd0.2 possessing the smallest ΔT (1.84 K). We synthesize and characterize 36 predicted compositions (9 feedback loops) from a potential space of ~800,000 compositions. Of these, 14 had smaller ΔT than any of the 22 in the original data set.

  19. Accelerated search for materials with targeted properties by adaptive design.

    PubMed

    Xue, Dezhen; Balachandran, Prasanna V; Hogden, John; Theiler, James; Xue, Deqing; Lookman, Turab

    2016-01-01

    Finding new materials with targeted properties has traditionally been guided by intuition, and trial and error. With increasing chemical complexity, the combinatorial possibilities are too large for an Edisonian approach to be practical. Here we show how an adaptive design strategy, tightly coupled with experiments, can accelerate the discovery process by sequentially identifying the next experiments or calculations, to effectively navigate the complex search space. Our strategy uses inference and global optimization to balance the trade-off between exploitation and exploration of the search space. We demonstrate this by finding very low thermal hysteresis (ΔT) NiTi-based shape memory alloys, with Ti50.0Ni46.7Cu0.8Fe2.3Pd0.2 possessing the smallest ΔT (1.84 K). We synthesize and characterize 36 predicted compositions (9 feedback loops) from a potential space of ∼800,000 compositions. Of these, 14 had smaller ΔT than any of the 22 in the original data set. PMID:27079901

  20. Accelerated search for materials with targeted properties by adaptive design.

    PubMed

    Xue, Dezhen; Balachandran, Prasanna V; Hogden, John; Theiler, James; Xue, Deqing; Lookman, Turab

    2016-04-15

    Finding new materials with targeted properties has traditionally been guided by intuition, and trial and error. With increasing chemical complexity, the combinatorial possibilities are too large for an Edisonian approach to be practical. Here we show how an adaptive design strategy, tightly coupled with experiments, can accelerate the discovery process by sequentially identifying the next experiments or calculations, to effectively navigate the complex search space. Our strategy uses inference and global optimization to balance the trade-off between exploitation and exploration of the search space. We demonstrate this by finding very low thermal hysteresis (ΔT) NiTi-based shape memory alloys, with Ti50.0Ni46.7Cu0.8Fe2.3Pd0.2 possessing the smallest ΔT (1.84 K). We synthesize and characterize 36 predicted compositions (9 feedback loops) from a potential space of ∼800,000 compositions. Of these, 14 had smaller ΔT than any of the 22 in the original data set.

  1. A demonstration of simple airfoils: Structural design and materials choices

    SciTech Connect

    Bunnell, L.R.; Piippo, S.W.

    1993-01-01

    An educational unit is presented for building and evaluating simple wing structures, in order to learn about materials choice and lightweight construction. This unit is appropriate for a high school materials science class or lower-division college courses in structural engineering, materials science, or aeronautical engineering.

  2. Functionally Graded Designer Viscoelastic Materials Tailored to Perform Prescribed Tasks with Probabilistic Failures and Lifetimes

    SciTech Connect

    Hilton, Harry H.

    2008-02-15

    Protocols are developed for formulating optimal viscoelastic designer functionally graded materials tailored to best respond to prescribed loading and boundary conditions. In essence, an inverse approach is adopted where material properties instead of structures per se are designed and then distributed throughout structural elements. The final measure of viscoelastic material efficacy is expressed in terms of failure probabilities vs. survival time000.

  3. 46 CFR 160.135-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Lifeboats § 160.135-23 Procedure for approval of design, material, or construction change. (a) Each change in design, material, or construction from the plans approved under 46 CFR 159.005-13 and §...

  4. 46 CFR 160.135-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Lifeboats (SOLAS) § 160.135-23 Procedure for approval of design, material, or construction change. (a) Each change in design, material, or construction from the plans approved under 46 CFR 159.005-13 and §...

  5. 46 CFR 160.135-23 - Procedure for approval of design, material, or construction change.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Lifeboats (SOLAS) § 160.135-23 Procedure for approval of design, material, or construction change. (a) Each change in design, material, or construction from the plans approved under 46 CFR 159.005-13 and §...

  6. Role of dislocation theory in the design of engineering materials

    SciTech Connect

    Morris, J.W. Jr.

    1980-06-01

    The science of materials development has progressed to a stage in which it is possible to compose a recipe for new materials. The recipe has three steps: given a desirable set of properties and material constraints, one identifies a composition and microstructure to achieve them; given a desirable composition and microstructure, one identifies a processing sequence to achieve them; given a trial alloy, one conducts analytical testing to identify its shortcomings and overcomes them. In effecting each stage of this recipe, it is usually necessary to be aware of and understand the role of the dislocations which determine material properties, define material microstructure, and control its evolution. The role of dislocations is discussed. The text contains examples of particular alloy development efforts, and suggestions for research in dislocation theory which might contribute to the solution of significant problems in materials development.

  7. Technologists Talk: Making the Links between Design, Problem-Solving and Experiences with Hard Materials

    ERIC Educational Resources Information Center

    Potter, Patricia

    2013-01-01

    Design and problem-solving is a key learning focus in technology education and remains a distinguishing factor that separates it from other subject areas. This research investigated how two expert designers considered experiences with hard materials contributed to their learning design and problem-solving with these materials. The research project…

  8. 46 CFR 164.019-9 - Procedure for acceptance of revisions of design, process, or materials.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 6 2010-10-01 2010-10-01 false Procedure for acceptance of revisions of design, process... Device Components § 164.019-9 Procedure for acceptance of revisions of design, process, or materials. (a) The manufacturer shall not change the design, material, manufacturing process, or construction of...

  9. Design Considerations of Help Options in Computer-Based L2 Listening Materials Informed by Participatory Design

    ERIC Educational Resources Information Center

    Cárdenas-Claros, Mónica Stella

    2015-01-01

    This paper reports on the findings of two qualitative exploratory studies that sought to investigate design features of help options in computer-based L2 listening materials. Informed by principles of participatory design, language learners, software designers, language teachers, and a computer programmer worked collaboratively in a series of…

  10. A strategy for designing effective patient education materials.

    PubMed

    McCabe, B J; Tysinger, J W; Kreger, M; Currwin, A C

    1989-09-01

    Health care professionals have long voiced a concern about the mismatch between patients' reading skills and the readability of printed educational materials. The gap between patients' reading levels and the readability of diet education materials has not been closed in the past 20 years. This article details a strategy for developing effective printed educational materials that was used to develop and revise dietetic materials for patients at a university medical center. The process includes the use of a computerized readability software program to assess reading levels. Three major steps are to (a) analyze patient education needs, (b) develop the instructional plan and materials, and (c) evaluate the materials. Examples are given of the application of the readability program in the development of one diet booklet and in the simplification of four other booklets. Without the readability formulas, the reading level of the materials would have remained above the stated educational levels of the target population, and the objectives of the booklets would not have been achieved. Cautions against overreliance on the readability formulas without other assessment steps are given. A systematic approach including readability assessment is needed to ensure the effectiveness of dietetic educational materials.

  11. Materials by Design-A Perspective From Atoms to Structures.

    PubMed

    Buehler, Markus J

    2013-02-01

    Biological materials are effectively synthesized, controlled, and used for a variety of purposes-in spite of limitations in energy, quality, and quantity of their building blocks. Whereas the chemical composition of materials in the living world plays a some role in achieving functional properties, the way components are connected at different length scales defines what material properties can be achieved, how they can be altered to meet functional requirements, and how they fail in disease states and other extreme conditions. Recent work has demonstrated this by using large-scale computer simulations to predict materials properties from fundamental molecular principles, combined with experimental work and new mathematical techniques to categorize complex structure-property relationships into a systematic framework. Enabled by such categorization, we discuss opportunities based on the exploitation of concepts from distinct hierarchical systems that share common principles in how function is created, linking music to materials science. PMID:24163499

  12. Materials by Design-A Perspective From Atoms to Structures.

    PubMed

    Buehler, Markus J

    2013-02-01

    Biological materials are effectively synthesized, controlled, and used for a variety of purposes-in spite of limitations in energy, quality, and quantity of their building blocks. Whereas the chemical composition of materials in the living world plays a some role in achieving functional properties, the way components are connected at different length scales defines what material properties can be achieved, how they can be altered to meet functional requirements, and how they fail in disease states and other extreme conditions. Recent work has demonstrated this by using large-scale computer simulations to predict materials properties from fundamental molecular principles, combined with experimental work and new mathematical techniques to categorize complex structure-property relationships into a systematic framework. Enabled by such categorization, we discuss opportunities based on the exploitation of concepts from distinct hierarchical systems that share common principles in how function is created, linking music to materials science.

  13. Towards intelligent microstructural design of Nanocomposite Materials. Lightweight, high strength structural/armor materials for service in extreme environments

    SciTech Connect

    Mara, Nathan Allan; Bronkhorst, Curt Allan; Beyerlein, Irene Jane

    2015-12-21

    The intent of this research effort is to prove the hypothesis that: Through the employment of controlled processing parameters which are based upon integrated advanced material characterization and multi-physics material modeling, bulk nanolayered composites can be designed to contain high densities of preferred interfaces that can serve as supersinks for the defects responsible for premature damage and failure.

  14. 46 CFR 128.220 - Class II non-vital systems-materials and pressure design.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... materials and pressure design of subchapter F of this chapter. (b) Piping for salt-water service must be of a corrosion-resistant material and, if ferrous, be hot-dip galvanized or be at least of...

  15. 46 CFR 128.220 - Class II non-vital systems-materials and pressure design.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... materials and pressure design of subchapter F of this chapter. (b) Piping for salt-water service must be of a corrosion-resistant material and, if ferrous, be hot-dip galvanized or be at least of...

  16. 46 CFR 128.220 - Class II non-vital systems-materials and pressure design.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... materials and pressure design of subchapter F of this chapter. (b) Piping for salt-water service must be of a corrosion-resistant material and, if ferrous, be hot-dip galvanized or be at least of...

  17. 46 CFR 128.220 - Class II non-vital systems-materials and pressure design.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... materials and pressure design of subchapter F of this chapter. (b) Piping for salt-water service must be of a corrosion-resistant material and, if ferrous, be hot-dip galvanized or be at least of...

  18. 46 CFR 128.220 - Class II non-vital systems-materials and pressure design.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... materials and pressure design of subchapter F of this chapter. (b) Piping for salt-water service must be of a corrosion-resistant material and, if ferrous, be hot-dip galvanized or be at least of...

  19. Computational Design of Novel, Radiation Resistant Fusion Materials

    SciTech Connect

    Kubota, A; Caturla, M J; Wirth, B D; Latkowski, J

    2003-02-01

    The promise of fusion as a viable 21st century energy source requires the development of advanced structural (MFE and IFE) and optical (IFE) materials that are capable of withstanding the harsh radiation environment that leads to the degradation of physical and mechanical properties. Materials in fusion environments must be able to handle 14 MeV neutrons produced from Deuterium-Tritium nuclear reactions, as well as the insoluble He and reactive H gases that lead to swelling and embrittlement. Additionally, with the requirement of very high thermal loads makes the development of new advanced materials a formidable challenge. The scope of this study was to determine the feasibility of using atomistic simulations to predict the radiation response of novel materials engineered with potentially self-healing properties to survive in radiation environments over very long time-scales. The class of materials that shows promise is what is called a nanocrystalline material. Nanocrystalline materials are defined as those having very fine grains on the order of several to tens of nanometers in size, and consequently very high grain-boundary to volume ratio. Experimental observations [1] suggests that these grain-boundary networks can act as sinks for defects and hence promote self-repair.

  20. Fabrication of a novel micron scale Y-structure-based chiral metamaterial: Simulation and experimental analysis of its chiral and negative index properties in the terahertz and microwave regimes.

    PubMed

    Wongkasem, Nantakan; Akyurtlu, Alkim; Marx, Kenneth A; Goodhue, William D; Li, Jin; Dong, Qi; Ada, Earl T

    2007-06-01

    In this report, we describe the fabrication of a chiral metamaterial based on a periodic array of Y-shaped Al structures on a dielectric Mylar substrate. The unit cell dimensions of the Y-structure are approximately 100 microm on a side with 8 microm linewidths. The fabricated Y-structure elements are characterized using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Quantitative elemental analyses were carried out on both the Y-structure, comprised of Al and its oxide, as well as adjacent regions of the underlying mylar substrate using the energy dispersive X-ray spectroscopy (EDS) capability of the SEM. Finite-Difference Time-Domain (FDTD) calculations of the negative index of refraction for a 3D wedge of multiple layers of the 2D metamaterials showed that these metamaterials possess double negative (-mu,-epsilon) electromagnetic bulk properties at THz frequencies. The same negative index of refraction was determined for a wedge comprised of appropriately scaled larger Y-structures simulated in the microwave region. This double negative property was confirmed experimentally by microwave measurements on a 3D wedge comprised of stacked and registered Y-structure sheets.

  1. Mechanical design engineering. NASA/university advanced design program: Lunar Bulk Material Transport Vehicle

    NASA Astrophysics Data System (ADS)

    Daugherty, Paul; Griner, Stewart; Hendrix, Alan; Makarov, Chris; Martiny, Stephen; Meyhoefer, Douglas Ralph; Platt, Cody Claxton; Sivak, John; Wheeler, Elizabeth Fitch

    1988-06-01

    The design of a Lunar Bulk Material Transport Vehicle (LBMTV) is discussed. Goals set in the project include a payload of 50 cubic feet of lunar soil with a lunar of approximately 800 moon-pounds, a speed of 15 mph, and the ability to handle a grade of 20 percent. Thermal control, an articulated steering mechanism, a dump mechanism, a self-righting mechanism, viable power sources, and a probable control panel are analyzed. The thermal control system involves the use of small strip heaters to heat the housing of electronic equipment in the absence of sufficient solar radiation and multi-layer insulation during periods of intense solar radiation. The entire system uses only 10 W and weighs about 60 pounds, or 10 moon-pounds. The steering mechanism is an articulated steering joint at the center of the vehicle. It utilizes two actuators and yields a turning radius of 10.3 feet. The dump mechanism rotates the bulk material container through an angle of 100 degree using one actuator. The self-righting mechanism consists of two four bar linkages, each of which is powered by the same size actuator as the other linkages. The LBMTV is powered by rechargeable batteries. A running time of at least two hours is attained under a worst case analysis. The weight of the batteries is 100 pounds. A control panel consisting of feedback and control instruments is described. The panel includes all critical information necessary to control the vehicle remotely. The LBMTV is capable of handling many types of cargo. It is able to interface with many types of removable bulk material containers. These containers are made to interface with the three-legged walker, SKITTER. The overall vehicle is about 15 feet in length and has a weight of about 1000 pounds, or 170 lunar pounds.

  2. Mechanical design engineering. NASA/university advanced design program: Lunar Bulk Material Transport Vehicle

    NASA Technical Reports Server (NTRS)

    Daugherty, Paul; Griner, Stewart; Hendrix, Alan; Makarov, Chris; Martiny, Stephen; Meyhoefer, Douglas Ralph; Platt, Cody Claxton; Sivak, John; Wheeler, Elizabeth Fitch

    1988-01-01

    The design of a Lunar Bulk Material Transport Vehicle (LBMTV) is discussed. Goals set in the project include a payload of 50 cubic feet of lunar soil with a lunar of approximately 800 moon-pounds, a speed of 15 mph, and the ability to handle a grade of 20 percent. Thermal control, an articulated steering mechanism, a dump mechanism, a self-righting mechanism, viable power sources, and a probable control panel are analyzed. The thermal control system involves the use of small strip heaters to heat the housing of electronic equipment in the absence of sufficient solar radiation and multi-layer insulation during periods of intense solar radiation. The entire system uses only 10 W and weighs about 60 pounds, or 10 moon-pounds. The steering mechanism is an articulated steering joint at the center of the vehicle. It utilizes two actuators and yields a turning radius of 10.3 feet. The dump mechanism rotates the bulk material container through an angle of 100 degree using one actuator. The self-righting mechanism consists of two four bar linkages, each of which is powered by the same size actuator as the other linkages. The LBMTV is powered by rechargeable batteries. A running time of at least two hours is attained under a worst case analysis. The weight of the batteries is 100 pounds. A control panel consisting of feedback and control instruments is described. The panel includes all critical information necessary to control the vehicle remotely. The LBMTV is capable of handling many types of cargo. It is able to interface with many types of removable bulk material containers. These containers are made to interface with the three-legged walker, SKITTER. The overall vehicle is about 15 feet in length and has a weight of about 1000 pounds, or 170 lunar pounds.

  3. 30 CFR 27.20 - Quality of material, workmanship, and design.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS METHANE-MONITORING SYSTEMS Construction and Design... its opinion, is constructed of suitable materials, is of good workmanship, is based on...

  4. 30 CFR 27.20 - Quality of material, workmanship, and design.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS METHANE-MONITORING SYSTEMS Construction and Design... its opinion, is constructed of suitable materials, is of good workmanship, is based on...

  5. First Materials Science Research Rack Capabilities and Design Features

    NASA Technical Reports Server (NTRS)

    Schaefer, D.; King, R.; Cobb, S.; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    The first Materials Science Research Rack (MSRR-1) will accommodate dual Experiment Modules (EM's) and provide simultaneous on-orbit processing operations capability. The first international Materials Science Experiment Module for the MSRR-1 is an international cooperative research activity between NASA's Marshall Space Flight Center (MSFC) and the European Space Agency's (ESA) European Space Research and Technology Center. (ESTEC). This International Standard Payload Rack (ISPR) will contain the Materials Science Laboratory (MSL) developed by ESA as an Experiment Module. The MSL Experiment Module will accommodate several on-orbit exchangeable experiment-specific Module Inserts. Module Inserts currently planned are a Quench Module Insert, Low Gradient Furnace, Solidification with Quench Furnace, and Diffusion Module Insert. The second Experiment Module for the MSRR-1 configuration is a commercial device supplied by MSFC's Space Products Department (SPD). It includes capabilities for vapor transport processes and liquid metal sintering. This Experiment Module will be replaced on-orbit with other NASA Materials Science EMs.

  6. Borderline Issues: Social and Material Aspects of Design.

    ERIC Educational Resources Information Center

    Brown, John Seely; Duguid, Paul

    1994-01-01

    Argues that the shared use of artifacts is supported by latent border resources that lie beyond the canonical artifact. Designers must understand the role border resources play and work more directly to help users develop them. This will require designers to change their understanding of artifacts and users. (Contains 69 references.) (KRN)

  7. Synthesis and design of intermetallic materials - molybdenum disilicide

    SciTech Connect

    Petrovic, J.J.; Castro, R.G.; Butt, D.P.

    1995-05-01

    The objective of this program is to develop structural silicide-based composite materials with optimum combinations of elevated temperature strength/creep resistance, low temperature fracture toughness, and high temperature oxidation resistance for applications of importance to the U.S. processing industry. A further objective is to develop silicide-based prototype industrial components. The ultimate aim of the program is to work with industry to transfer the structural silicide materials technology to the private sector in order to promote international competitiveness in the area of advanced high temperature composite materials and important applications in major energy-intensive U.S. processing industries. The program presently has a number of developing industrial connections, including a CRADA with the advanced materials company Advanced Refractory Technologies Inc. and interactions targeted at developing industrial gas burner and metal and glass melting/processing applications. Current experimental emphasis is on the development and characterization of SiC reinforced-MoSi{sub 2} matrix composites, plasma sprayed MoSi{sub 2}-based materials and microlaminate composites, and MoSi{sub 2} reinforced-Si{sub 3}N{sub 4} matrix composites. We are developing processing methods for MoSi{sub 2{minus}}based materials and microlaminate composites, and MoSi{sub 2} reinforced-Si{sub 3}N{sub 4} matrix composites. We are developing processing methods for MoSi{sub 2{minus}} based materials, such as plasma spraying/spray forming and electrophoretic deposition. We are also pursuing the fabrication of prototype industrial gas burner and injection tube components of these materials, as well as prototype components for glass processing.

  8. Bioreceptivity evaluation of cementitious materials designed to stimulate biological growth.

    PubMed

    Manso, Sandra; De Muynck, Willem; Segura, Ignacio; Aguado, Antonio; Steppe, Kathy; Boon, Nico; De Belie, Nele

    2014-05-15

    Ordinary Portland cement (OPC), the most used binder in construction, presents some disadvantages in terms of pollution (CO2 emissions) and visual impact. For this reason, green roofs and façades have gain considerable attention in the last decade as a way to integrate nature in cities. These systems, however, suffer from high initial and maintenance costs. An alternative strategy to obtain green facades is the direct natural colonisation of the cementitious construction materials constituting the wall, a phenomenon governed by the bioreceptivity of such material. This work aims at assessing the suitability of magnesium phosphate cement (MPC) materials to allow a rapid natural colonisation taking carbonated OPC samples as a reference material. For that, the aggregate size, the w/c ratio and the amount of cement paste of mortars made of both binders were modified. The assessment of the different bioreceptivities was conducted by means of an accelerated algal fouling test. MPC samples exhibited a faster fouling compared to OPC samples, which could be mainly attributed to the lower pH of the MPC binder. In addition to the binder, the fouling rate was governed by the roughness and the porosity of the material. MPC mortar with moderate porosity and roughness appears to be the most feasible material to be used for the development of green concrete walls. PMID:24602907

  9. Bioreceptivity evaluation of cementitious materials designed to stimulate biological growth.

    PubMed

    Manso, Sandra; De Muynck, Willem; Segura, Ignacio; Aguado, Antonio; Steppe, Kathy; Boon, Nico; De Belie, Nele

    2014-05-15

    Ordinary Portland cement (OPC), the most used binder in construction, presents some disadvantages in terms of pollution (CO2 emissions) and visual impact. For this reason, green roofs and façades have gain considerable attention in the last decade as a way to integrate nature in cities. These systems, however, suffer from high initial and maintenance costs. An alternative strategy to obtain green facades is the direct natural colonisation of the cementitious construction materials constituting the wall, a phenomenon governed by the bioreceptivity of such material. This work aims at assessing the suitability of magnesium phosphate cement (MPC) materials to allow a rapid natural colonisation taking carbonated OPC samples as a reference material. For that, the aggregate size, the w/c ratio and the amount of cement paste of mortars made of both binders were modified. The assessment of the different bioreceptivities was conducted by means of an accelerated algal fouling test. MPC samples exhibited a faster fouling compared to OPC samples, which could be mainly attributed to the lower pH of the MPC binder. In addition to the binder, the fouling rate was governed by the roughness and the porosity of the material. MPC mortar with moderate porosity and roughness appears to be the most feasible material to be used for the development of green concrete walls.

  10. Advanced algorithms for radiographic material discrimination and inspection system design

    NASA Astrophysics Data System (ADS)

    Gilbert, Andrew J.; McDonald, Benjamin S.; Deinert, Mark R.

    2016-10-01

    X-ray and neutron radiography are powerful tools for non-invasively inspecting the interior of objects. However, current methods are limited in their ability to differentiate materials when multiple materials are present, especially within large and complex objects. Past work has demonstrated that the spectral shift that X-ray beams undergo in traversing an object can be used to detect and quantify nuclear materials. The technique uses a spectrally sensitive detector and an inverse algorithm that varies the composition of the object until the X-ray spectrum predicted by X-ray transport matches the one measured. Here we show that this approach can be adapted to multi-mode radiography, with energy integrating detectors, and that the Cramér-Rao lower bound can be used to choose an optimal set of inspection modes a priori. We consider multi-endpoint X-ray radiography alone, or in combination with neutron radiography using deuterium-deuterium (DD) or deuterium-tritium (DT) sources. We show that for an optimal mode choice, the algorithm can improve discrimination between high-Z materials, specifically between tungsten and plutonium, and estimate plutonium mass within a simulated nuclear material storage system to within 1%.

  11. A database to enable discovery and design of piezoelectric materials

    PubMed Central

    de Jong, Maarten; Chen, Wei; Geerlings, Henry; Asta, Mark; Persson, Kristin Aslaug

    2015-01-01

    Piezoelectric materials are used in numerous applications requiring a coupling between electrical fields and mechanical strain. Despite the technological importance of this class of materials, for only a small fraction of all inorganic compounds which display compatible crystallographic symmetry, has piezoelectricity been characterized experimentally or computationally. In this work we employ first-principles calculations based on density functional perturbation theory to compute the piezoelectric tensors for nearly a thousand compounds, thereby increasing the available data for this property by more than an order of magnitude. The results are compared to select experimental data to establish the accuracy of the calculated properties. The details of the calculations are also presented, along with a description of the format of the database developed to make these computational results publicly available. In addition, the ways in which the database can be accessed and applied in materials development efforts are described. PMID:26451252

  12. A database to enable discovery and design of piezoelectric materials.

    PubMed

    de Jong, Maarten; Chen, Wei; Geerlings, Henry; Asta, Mark; Persson, Kristin Aslaug

    2015-01-01

    Piezoelectric materials are used in numerous applications requiring a coupling between electrical fields and mechanical strain. Despite the technological importance of this class of materials, for only a small fraction of all inorganic compounds which display compatible crystallographic symmetry, has piezoelectricity been characterized experimentally or computationally. In this work we employ first-principles calculations based on density functional perturbation theory to compute the piezoelectric tensors for nearly a thousand compounds, thereby increasing the available data for this property by more than an order of magnitude. The results are compared to select experimental data to establish the accuracy of the calculated properties. The details of the calculations are also presented, along with a description of the format of the database developed to make these computational results publicly available. In addition, the ways in which the database can be accessed and applied in materials development efforts are described.

  13. A Computational Method for Materials Design of New Interfaces

    NASA Astrophysics Data System (ADS)

    Kaminski, Jakub; Ratsch, Christian; Weber, Justin; Haverty, Michael; Shankar, Sadasivan

    2015-03-01

    We propose a novel computational approach to explore the broad configurational space of possible interfaces formed from known crystal structures to find new heterostructure materials with potentially interesting properties. In a series of steps with increasing complexity and accuracy, the vast number of possible combinations is narrowed down to a limited set of the most promising and chemically compatible candidates. This systematic screening encompasses (i) establishing the geometrical compatibility along multiple crystallographic orientations of two materials, (ii) simple functions eliminating configurations with unfavorable interatomic steric conflicts, (iii) application of empirical and semi-empirical potentials estimating approximate energetics and structures, (iv) use of DFT based quantum-chemical methods to ascertain the final optimal geometry and stability of the interface in question. For efficient high-throughput screening we have developed a new method to calculate surface energies, which allows for fast and systematic treatment of materials terminated with non-polar surfaces. We show that our approach leads to a maximum error around 3% from the exact reference. The representative results from our search protocol will be presented for selected materials including semiconductors and oxides.

  14. Design for a 1 MHz soft magnetic material hysteresisgraph (abstract)

    NASA Astrophysics Data System (ADS)

    Dennison, Eric

    1993-05-01

    Until recently, high frequency (1 MHz) testing of magnetically soft materials has been typically limited to measurement of core loss and peak or inductive ac permeability. A high frequency hysteresisgraph allows direct examination of the hysteresis loop and calculation of values for magnetic parameters such as coercivity (Hc), peak permeability (μp), remanence (Br), core loss (Pc,Pcv,Pcm), bias drive field strength (Hbias), maximum H drive (Hmax) and maximum or saturation induction (Bmax). This paper describes the methods used to construct and calibrate a commercial high frequency magnetic hysteresisgraph which is capable of recording the primary current and secondary voltage waveforms of magnetic cores driven at up to 1 MHz. A system accuracy of 2% (for B and H parameter values) and 5% (for core loss) was achieved through careful control and calibration of signal phase shifts within the circuitry. System calibration, magnetic field calculations, and use of FFT post-processing of the acquired waveforms are discussed. The ability to accurately record the hysteresis loop of a material at 1 MHz allows high frequency core materials to be characterized not only by core loss and permeability, but by their hysteresis loop shape, coercivity, and remanence, both under pure ac and dc biased ac drive conditions. Changes in material characteristics due to dc biasing, temperature variations, defects, or mechanical stresses can be readily observed and described in terms of changes to the hysteresis curve shape.

  15. Performance of pavements designed with low-cost materials

    NASA Astrophysics Data System (ADS)

    Grau, R. W.; Yrjanson, W. A.; Packard, R. G.; Barksdale, R. D.; Potts, C. F.; Ruth, B. E.; Smith, L. L.; Huddleston, I. J.; Vinson, T. S.; Hicks, R. G.

    1980-04-01

    The following areas are discussed. Utilization of marginal aggregate materials for secondary road surface layers; econocrete pavements; current practices; construction and performance of sand-asphalt bases and performance of sand-asphalt and limerock pavements in Florida. Cement stabilization of degrading aggregates use of crushed stone screenings in highway construction (abridgement); and sulfur-asphalt pavement technology are also reviewed.

  16. The Empirical Attitude, Material Practice and Design Activities

    ERIC Educational Resources Information Center

    Apedoe, Xornam; Ford, Michael

    2010-01-01

    This article is an argument about something that is both important and severely underemphasized in most current science curricula. The empirical attitude, fundamental to science since Galileo, is a habit of mind that motivates an active search for feedback on our ideas from the material world. Although more simple views of science manifest the…

  17. Photovoltaic module encapsulation design and materials section, volume 2

    NASA Technical Reports Server (NTRS)

    Cuddihy, E. F.

    1984-01-01

    Tests for chemical structure, material properties, water absorption, aging and curing agent of Ethylene Vinyl Acetate (EVA) and UV absorption studies are carried out. A computer model was developed for thermal optical modeling, to investigate dependence between module operating temperature and solar insolation, and heat dissapation behavior. Structural analyses were performed in order to determine the stress distribution under wind and heat conditions. Curves are shown for thermal loading conditions. An electrical isolation was carried out to investigate electrical stress aging of non-metallic encapsulation materials and limiting material flaws, and to develop a computer model of electrical fields and stresses in encapsulation materials. In addition, a mathematical model was developed and tests were conducted to predict hygroscopic and thermal expansion and contraction on a plastic coated wooden substrate. Thermal cycle and humidity freezing cycle tests, partial discharge tests, and hail impact tests were also carried out. Finally, the effects of soiling on the surface of photovoltaic modules were investigated. Two antisoiling coatings, a fluorinated silane and perflourodecanoic acid were considered.

  18. Designing Competency-Based Materials for the Automotive Mechanics Curriculum

    ERIC Educational Resources Information Center

    Richardson, Roger L.

    1977-01-01

    Describes the Career Education Center's (Florida State University) development of the "Automotive Mechanics Catalog" (a job inventory noting performance objectives for specific occupational programs), using the Vocational-Technical Education Consortium of States (V-TECS) model. Also describes the development of curriculum materials using the…

  19. Design of a scientific probe for obtaining Mars surface material

    NASA Technical Reports Server (NTRS)

    1990-01-01

    With the recent renewed interest in interplanetary and deep space exploratory missions, the Red Planet, Mars, which has captured people's imagination for centuries, has again become a center of attention. In the late 1960s and early 1970s, a series of Mariner missions performed fly-by investigations of the Mars surface and atmosphere. Later, in the mid 1970s, the data gathered by these earlier Mariner missions provided the basis of the much-publicized Viking missions, whose main objective was to determine the possibility of extraterrestrial life on Mars. More recently, with the dramatic changes in international politics, ambitious joint manned missions between the United States and the Soviet Union have been proposed to be launched in the early 21st century. In light of these exciting developments, the Spacecraft Design course, which was newly established at UCLA under NASA/USRA sponsorship, has developed its curriculum around a design project: the synthesis of an unmanned Martian landing probe. The students are required to conceive a preliminary design of a small spacecraft that is capable of landing at a designated site, collecting soil samples, and then returning the samples to orbit. The goal of the project is to demonstrate the feasibility of such a mission. This preliminary study of an interplanetary exploration mission has shown the feasibility of such a mission. The students have learned valuable lessons about the complexity of spacecraft design, even though the mission is relatively simple.

  20. Designing for time-dependent material response in spacecraft structures

    NASA Technical Reports Server (NTRS)

    Hyer, M. W.; Oleksuk, Lynda L. S.; Bowles, D. E.

    1992-01-01

    To study the influence on overall deformations of the time-dependent constitutive properties of fiber-reinforced polymeric matrix composite materials being considered for use in orbiting precision segmented reflectors, simple sandwich beam models are developed. The beam models include layers representing the face sheets, the core, and the adhesive bonding of the face sheets to the core. A three-layer model lumps the adhesive layers with the face sheets or core, while a five-layer model considers the adhesive layers explicitly. The deformation response of the three-layer and five-layer sandwich beam models to a midspan point load is studied. This elementary loading leads to a simple analysis, and it is easy to create this loading in the laboratory. Using the correspondence principle of viscoelasticity, the models representing the elastic behavior of the two beams are transformed into time-dependent models. Representative cases of time-dependent material behavior for the facesheet material, the core material, and the adhesive are used to evaluate the influence of these constituents being time-dependent on the deformations of the beam. As an example of the results presented, if it assumed that, as a worst case, the polymer-dominated shear properties of the core behave as a Maxwell fluid such that under constant shear stress the shear strain increases by a factor of 10 in 20 years, then it is shown that the beam deflection increases by a factor of 1.4 during that time. In addition to quantitative conclusions, several assumptions are discussed which simplify the analyses for use with more complicated material models. Finally, it is shown that the simpler three-layer model suffices in many situations.

  1. Nonstoichiometric Laser Materials: Designer Wavelengths in Neodymium Doped Garnets

    NASA Technical Reports Server (NTRS)

    Walsh, Brian M.; Barnes, Norman P.

    2008-01-01

    The tunable nature of lasers provides for a wide range of applications. Most applications rely on finding available laser wavelengths to meet the needs of the research. This article presents the concept of compositional tuning, whereby the laser wavelength is designed by exploiting nonstoichiometry. For research where precise wavelengths are required, such as remote sensing, this is highly advantageous. A theoretical basis for the concept is presented and experimental results in spectroscopic measurements support the theoretical basis. Laser operation nicely demonstrates the validity of the concept of designer lasers.

  2. Structural design methodologies for ceramic-based material systems

    NASA Technical Reports Server (NTRS)

    Duffy, Stephen F.; Chulya, Abhisak; Gyekenyesi, John P.

    1991-01-01

    One of the primary pacing items for realizing the full potential of ceramic-based structural components is the development of new design methods and protocols. The focus here is on low temperature, fast-fracture analysis of monolithic, whisker-toughened, laminated, and woven ceramic composites. A number of design models and criteria are highlighted. Public domain computer algorithms, which aid engineers in predicting the fast-fracture reliability of structural components, are mentioned. Emphasis is not placed on evaluating the models, but instead is focused on the issues relevant to the current state of the art.

  3. Structural design methodologies for ceramic-based material systems

    NASA Technical Reports Server (NTRS)

    Duffy, Stephen F.; Chulya, Abhisak; Gyekenyesi, John P.

    1992-01-01

    One of the primary pacing items for realizing the full potential of ceramic-based structural components is the development of new design methods and protocols. The focus here is on low temperature, fast-fracture analysis of monolithic, whisker-toughened, laminated, and woven ceramic composites. A number of design models and criteria are highlighted. Public domain computer algorithms, which aid engineers in predicting the fast-fracture reliability of structural components, are mentioned. Emphasis is not placed on evaluating the models, but instead is focused on the issues relevant to the current state of the art.

  4. 14 CFR 27.613 - Material strength properties and design values.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Material strength properties and design values. 27.613 Section 27.613 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction General § 27.613 Material strength properties...

  5. 14 CFR 29.613 - Material strength properties and design values.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Material strength properties and design values. 29.613 Section 29.613 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Design and Construction General § 29.613 Material strength properties...

  6. Designing Web-Based Educative Curriculum Materials for the Social Studies

    ERIC Educational Resources Information Center

    Callahan, Cory; Saye, John; Brush, Thomas

    2013-01-01

    This paper reports on a design experiment of web-based curriculum materials explicitly created to help social studies teachers develop their professional teaching knowledge. Web-based social studies curriculum reform efforts, human-centered interface design, and investigations into educative curriculum materials are reviewed, as well as…

  7. 36 CFR 401.5 - Control and supervision of materials, design, and building.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true Control and supervision of materials, design, and building. 401.5 Section 401.5 Parks, Forests, and Public Property AMERICAN BATTLE MONUMENTS COMMISSION MONUMENTS AND MEMORIALS § 401.5 Control and supervision of materials, design,...

  8. 36 CFR 401.5 - Control and supervision of materials, design, and building.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Control and supervision of materials, design, and building. 401.5 Section 401.5 Parks, Forests, and Public Property AMERICAN BATTLE MONUMENTS COMMISSION MONUMENTS AND MEMORIALS § 401.5 Control and supervision of materials, design,...

  9. 36 CFR 401.5 - Control and supervision of materials, design, and building.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false Control and supervision of materials, design, and building. 401.5 Section 401.5 Parks, Forests, and Public Property AMERICAN BATTLE MONUMENTS COMMISSION MONUMENTS AND MEMORIALS § 401.5 Control and supervision of materials, design,...

  10. 36 CFR 401.5 - Control and supervision of materials, design, and building.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Control and supervision of materials, design, and building. 401.5 Section 401.5 Parks, Forests, and Public Property AMERICAN BATTLE MONUMENTS COMMISSION MONUMENTS AND MEMORIALS § 401.5 Control and supervision of materials, design,...

  11. 36 CFR 401.5 - Control and supervision of materials, design, and building.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Control and supervision of materials, design, and building. 401.5 Section 401.5 Parks, Forests, and Public Property AMERICAN BATTLE MONUMENTS COMMISSION MONUMENTS AND MEMORIALS § 401.5 Control and supervision of materials, design,...

  12. A Tutorial Design Process Applied to an Introductory Materials Engineering Course

    ERIC Educational Resources Information Center

    Rosenblatt, Rebecca; Heckler, Andrew F.; Flores, Katharine

    2013-01-01

    We apply a "tutorial design process", which has proven to be successful for a number of physics topics, to design curricular materials or "tutorials" aimed at improving student understanding of important concepts in a university-level introductory materials science and engineering course. The process involves the identification…

  13. 46 CFR 128.230 - Penetrations of hulls and watertight bulkheads-materials and pressure design.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (CONTINUED) OFFSHORE SUPPLY VESSELS MARINE ENGINEERING: EQUIPMENT AND SYSTEMS Materials and Pressure Design § 128.230 Penetrations of hulls and watertight bulkheads—materials and pressure design. (a) Each piping... 46 Shipping 4 2010-10-01 2010-10-01 false Penetrations of hulls and watertight...

  14. 46 CFR 128.240 - Hydraulic or pneumatic power and control-materials and pressure design.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard piping component... 46 Shipping 4 2012-10-01 2012-10-01 false Hydraulic or pneumatic power and control-materials and pressure design. 128.240 Section 128.240 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY...

  15. 46 CFR 128.240 - Hydraulic or pneumatic power and control-materials and pressure design.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard piping component... 46 Shipping 4 2013-10-01 2013-10-01 false Hydraulic or pneumatic power and control-materials and pressure design. 128.240 Section 128.240 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY...

  16. 46 CFR 128.240 - Hydraulic or pneumatic power and control-materials and pressure design.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard piping component... 46 Shipping 4 2014-10-01 2014-10-01 false Hydraulic or pneumatic power and control-materials and pressure design. 128.240 Section 128.240 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY...

  17. The Effectiveness of Scaffolding Design in Training Writing Skills Physics Teaching Materials

    ERIC Educational Resources Information Center

    Sinaga, Parlindungan; Suhandi, Andi; Liliasari

    2015-01-01

    Result of field studies showed low writing skill of teachers in teaching material. The root of the problem lies in their inability on translating description of teaching material into writing. This research focused on the effectiveness of scaffolding design. The scaffolding design was tested in the selected topics of physics courses for…

  18. Material Development to Raise Awareness of Using Smart Boards: An Example Design and Development Research

    ERIC Educational Resources Information Center

    Günaydin, Serpil; Karamete, Aysen

    2016-01-01

    This study aims to develop training material that will help raise awareness in prospective teachers regarding the benefits of using smart boards in the classroom. In this study, a Type 2 design and development research method (DDR) was used. The material was developed by applying phases of ADDIE--an instructional systems design model. The…

  19. Materials technology assessment for a 1050 K Stirling Space Engine design

    SciTech Connect

    Scheuermann, C.M.; Dreshfield, R.L.; Gaydosh, D.J.; Kiser, J.D.; MacKay, R.A.; McDanels, D.L.; Petrasek, D.W.; Vannucci, R.D.; Bowles, K.J.; Watson, G.K.

    1988-10-01

    An assessment of materials technology and proposed materials selection was made for the 1050 K (superalloy) Stirling Space Engine design. The objectives of this assessment were to evaluate previously proposed materials selections, evaluate the current state-of-the-art materials, propose potential alternate materials selections and identify research and development efforts needed to provide materials that can meet the stringent system requirements. This assessment generally reaffirmed the choices made by the contractor; however, in many cases alternative choices were described and suggestions for needed materials and fabrication research and development were made.

  20. Materials technology assessment for a 1050 K Stirling space engine design

    NASA Technical Reports Server (NTRS)

    Scheuermann, Coulson M.; Dreshfield, Robert L.; Gaydosh, Darrell J.; Kiser, James D.; Mackay, Rebecca A.; Mcdaniels, David L.; Petrasek, Donald W.; Vannucci, Raymond D.; Bowles, Kenneth J.; Watson, Gordon K.

    1988-01-01

    An assessment of materials technology and proposed materials selection was made for the 1050 K (superalloy) Stirling Space Engine design. The objectives of this assessment were to evaluate previously proposed materials selections, evaluate the current state-of-the-art materials, propose potential alternate materials selections and identify research and development efforts needed to provide materials that can meet the stringent system requirements. This assessment generally reaffirmed the choices made by the contractor. However, in many cases alternative choices were described and suggestions for needed materials and fabrication research and development were made.

  1. Mapping Chemical Selection Pathways for Designing Multicomponent Alloys: an informatics framework for materials design.

    PubMed

    Srinivasan, Srikant; Broderick, Scott R; Zhang, Ruifeng; Mishra, Amrita; Sinnott, Susan B; Saxena, Surendra K; LeBeau, James M; Rajan, Krishna

    2015-12-18

    A data driven methodology is developed for tracking the collective influence of the multiple attributes of alloying elements on both thermodynamic and mechanical properties of metal alloys. Cobalt-based superalloys are used as a template to demonstrate the approach. By mapping the high dimensional nature of the systematics of elemental data embedded in the periodic table into the form of a network graph, one can guide targeted first principles calculations that identify the influence of specific elements on phase stability, crystal structure and elastic properties. This provides a fundamentally new means to rapidly identify new stable alloy chemistries with enhanced high temperature properties. The resulting visualization scheme exhibits the grouping and proximity of elements based on their impact on the properties of intermetallic alloys. Unlike the periodic table however, the distance between neighboring elements uncovers relationships in a complex high dimensional information space that would not have been easily seen otherwise. The predictions of the methodology are found to be consistent with reported experimental and theoretical studies. The informatics based methodology presented in this study can be generalized to a framework for data analysis and knowledge discovery that can be applied to many material systems and recreated for different design objectives.

  2. Mapping Chemical Selection Pathways for Designing Multicomponent Alloys: an informatics framework for materials design.

    PubMed

    Srinivasan, Srikant; Broderick, Scott R; Zhang, Ruifeng; Mishra, Amrita; Sinnott, Susan B; Saxena, Surendra K; LeBeau, James M; Rajan, Krishna

    2015-01-01

    A data driven methodology is developed for tracking the collective influence of the multiple attributes of alloying elements on both thermodynamic and mechanical properties of metal alloys. Cobalt-based superalloys are used as a template to demonstrate the approach. By mapping the high dimensional nature of the systematics of elemental data embedded in the periodic table into the form of a network graph, one can guide targeted first principles calculations that identify the influence of specific elements on phase stability, crystal structure and elastic properties. This provides a fundamentally new means to rapidly identify new stable alloy chemistries with enhanced high temperature properties. The resulting visualization scheme exhibits the grouping and proximity of elements based on their impact on the properties of intermetallic alloys. Unlike the periodic table however, the distance between neighboring elements uncovers relationships in a complex high dimensional information space that would not have been easily seen otherwise. The predictions of the methodology are found to be consistent with reported experimental and theoretical studies. The informatics based methodology presented in this study can be generalized to a framework for data analysis and knowledge discovery that can be applied to many material systems and recreated for different design objectives. PMID:26681142

  3. Mapping Chemical Selection Pathways for Designing Multicomponent Alloys: an informatics framework for materials design

    NASA Astrophysics Data System (ADS)

    Srinivasan, Srikant; Broderick, Scott R.; Zhang, Ruifeng; Mishra, Amrita; Sinnott, Susan B.; Saxena, Surendra K.; Lebeau, James M.; Rajan, Krishna

    2015-12-01

    A data driven methodology is developed for tracking the collective influence of the multiple attributes of alloying elements on both thermodynamic and mechanical properties of metal alloys. Cobalt-based superalloys are used as a template to demonstrate the approach. By mapping the high dimensional nature of the systematics of elemental data embedded in the periodic table into the form of a network graph, one can guide targeted first principles calculations that identify the influence of specific elements on phase stability, crystal structure and elastic properties. This provides a fundamentally new means to rapidly identify new stable alloy chemistries with enhanced high temperature properties. The resulting visualization scheme exhibits the grouping and proximity of elements based on their impact on the properties of intermetallic alloys. Unlike the periodic table however, the distance between neighboring elements uncovers relationships in a complex high dimensional information space that would not have been easily seen otherwise. The predictions of the methodology are found to be consistent with reported experimental and theoretical studies. The informatics based methodology presented in this study can be generalized to a framework for data analysis and knowledge discovery that can be applied to many material systems and recreated for different design objectives.

  4. Mapping Chemical Selection Pathways for Designing Multicomponent Alloys: an informatics framework for materials design

    PubMed Central

    Srinivasan, Srikant; Broderick, Scott R.; Zhang, Ruifeng; Mishra, Amrita; Sinnott, Susan B.; Saxena, Surendra K.; LeBeau, James M.; Rajan, Krishna

    2015-01-01

    A data driven methodology is developed for tracking the collective influence of the multiple attributes of alloying elements on both thermodynamic and mechanical properties of metal alloys. Cobalt-based superalloys are used as a template to demonstrate the approach. By mapping the high dimensional nature of the systematics of elemental data embedded in the periodic table into the form of a network graph, one can guide targeted first principles calculations that identify the influence of specific elements on phase stability, crystal structure and elastic properties. This provides a fundamentally new means to rapidly identify new stable alloy chemistries with enhanced high temperature properties. The resulting visualization scheme exhibits the grouping and proximity of elements based on their impact on the properties of intermetallic alloys. Unlike the periodic table however, the distance between neighboring elements uncovers relationships in a complex high dimensional information space that would not have been easily seen otherwise. The predictions of the methodology are found to be consistent with reported experimental and theoretical studies. The informatics based methodology presented in this study can be generalized to a framework for data analysis and knowledge discovery that can be applied to many material systems and recreated for different design objectives. PMID:26681142

  5. Biochemically designed polymers as self-organized materials

    NASA Astrophysics Data System (ADS)

    Alva, Shridhara; Sarma, Rupmoni; Marx, Kenneth A.; Kumar, Jayant; Tripathy, Sukant K.; Akkara, Joseph A.; Kaplan, David L.

    1997-02-01

    Self assembled molecular systems are a focus of attention for material scientists as they provide an inherent molecular level organization responsible for enhanced material properties. We have developed polymeric molecular systems with interesting optical properties by biochemical engineering, which can be self assembled to thin films. Horseradish peroxidase catalyzed polymerizations of phenolic monomers: 9-hydroxyquinoline-5-sulfonic acid, acid red and decyl ester (d&l isomers) of tyrosine, have been achieved in the presence of hydrogen peroxide. The polymer of 8- hydroxyquinoline-5-sulfonic acid acts as a polymeric ligand that can be used for metal ion sensing. The polymer of acid red, with azo functional groups in the polymer backbone, shows interesting optical properties. Amphiphilic derivatives of tyrosine self assemble into tubules from micelles in aqueous solutions. These tubules have been enzymatically polymerized to polymeric tubules. The tubules are of 5 micrometers average diameter and > 200 micrometers length. The formation and properties of these tubules are discussed.

  6. Computational Design of Materials for Monolithic Integration with Si

    NASA Astrophysics Data System (ADS)

    Moll, Nikolaj

    2000-03-01

    A novel class of semiconductors is introduced which is optically active and solves the problems with lattice-constant mismatches and polarity mismatches that normally are an issue in heteroepitaxial growth of III-V alloys on silicon substrates. Using ab initio total energy calculations and quasi-particle GW calculations the physical properties of various configurations of these novel materials are computed. A particular suitable configuration is identified. This configuration is lattice-constant matched to Si. Estimated thermal expansion coefficients indicate that the lattice constant continues to match at room temperature. This lattice-constant matched configuration also possesses a direct band gap which is very close to the operating wavelength of optical fibers. Therefore this novel class could lead to monolithic integration of optical materials and Si circuits. Further configurations are investigated and discussed which exhibit properties that could be useful for other technological applications such as far infrared detectors and emitters.

  7. Recent progress in supercapacitors: from materials design to system construction.

    PubMed

    Wang, Yonggang; Xia, Yongyao

    2013-10-01

    Supercapacitors are currently attracting intensive attention because they can provide energy density by orders of magnitude higher than dielectric capacitors, greater power density, and longer cycling ability than batteries. The main challenge for supercapacitors is to develop them with high energy density that is close to that of a current rechargeable battery, while maintaining their inherent characteristics of high power and long cycling life. Consequently, much research has been devoted to enhance the performance of supercapacitors by either maximizing the specific capacitance and/or increasing the cell voltage. The latest advances in the exploration and development of new supercapacitor systems and related electrode materials are highlighted. Also, the prospects and challenges in practical application are analyzed, aiming to give deep insights into the material science and electrochemical fields.

  8. Evolutionary Design of a Robotic Material Defect Detection System

    NASA Technical Reports Server (NTRS)

    Ballard, Gary; Howsman, Tom; Craft, Mike; ONeil, Daniel; Steincamp, Jim; Howell, Joe T. (Technical Monitor)

    2002-01-01

    During the post-flight inspection of SSME engines, several inaccessible regions must be disassembled to inspect for defects such as cracks, scratches, gouges, etc. An improvement to the inspection process would be the design and development of very small robots capable of penetrating these inaccessible regions and detecting the defects. The goal of this research was to utilize an evolutionary design approach for the robotic detection of these types of defects. A simulation and visualization tool was developed prior to receiving the hardware as a development test bed. A small, commercial off-the-shelf (COTS) robot was selected from several candidates as the proof of concept robot. The basic approach to detect the defects was to utilize Cadmium Sulfide (CdS) sensors to detect changes in contrast of an illuminated surface. A neural network, optimally designed utilizing a genetic algorithm, was employed to detect the presence of the defects (cracks). By utilization of the COTS robot and US sensors, the research successfully demonstrated that an evolutionarily designed neural network can detect the presence of surface defects.

  9. 30 CFR 18.92 - Quality of material and design.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Field... shall be designed to facilitate maintenance and inspection. (b) MSHA shall conduct field investigations and, where necessary, field test electric machinery only where such machinery is found to...

  10. 30 CFR 18.92 - Quality of material and design.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Field... shall be designed to facilitate maintenance and inspection. (b) MSHA shall conduct field investigations and, where necessary, field test electric machinery only where such machinery is found to...

  11. 30 CFR 18.92 - Quality of material and design.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Field... shall be designed to facilitate maintenance and inspection. (b) MSHA shall conduct field investigations and, where necessary, field test electric machinery only where such machinery is found to...

  12. 30 CFR 18.92 - Quality of material and design.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Field... shall be designed to facilitate maintenance and inspection. (b) MSHA shall conduct field investigations and, where necessary, field test electric machinery only where such machinery is found to...

  13. Design of a scientific probe for obtaining Mars surface material

    NASA Technical Reports Server (NTRS)

    Baker, Miles; Deyerl, Eric; Gibson, Tim; Langberg, Bob; Yee, Terrance (Editor)

    1990-01-01

    The objective is to return a 1 Kg Martian soil sample from the surface of Mars to a mothership in a 60 km Mars orbit. Given here is information on the mission profile, the structural design and component placement, thermal control and guidance, propulsion systems, orbital mechanics, and specialized structures.

  14. Investigating Preservice Mathematics Teachers' Manipulative Material Design Processes

    ERIC Educational Resources Information Center

    Sandir, Hakan

    2016-01-01

    Students use concrete manipulatives to form an imperative affiliation between conceptual and procedural knowledge (Balka, 1993). Hence, it is necessary to design specific mathematics manipulatives that focus on different mathematical concepts. Preservice teachers need to know how to make and use manipulatives that stimulate students' thinking as…

  15. 30 CFR 18.92 - Quality of material and design.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Field... shall be designed to facilitate maintenance and inspection. (b) MSHA shall conduct field investigations and, where necessary, field test electric machinery only where such machinery is found to...

  16. A Computational Method for Materials Design of Interfaces

    NASA Astrophysics Data System (ADS)

    Kaminski, Jakub; Ratsch, Christian; Shankar, Sadasivan

    2014-03-01

    In the present work we propose a novel computational approach to explore the broad configurational space of possible interfaces formed from known crystal structures to find new hetrostructure materials with potentially interesting properties. In the series of subsequent steps with increasing complexity and accuracy, the vast number of possible combinations is narrowed down to a limited set of the most promising and chemically compatible candidates. This systematic screening encompasses (i) establishing the geometrical compatibility along multiple crystallographic orientations of two (or more) materials, (ii) simple functions eliminating configurations with unfavorable interatomic steric conflicts, (iii) application of empirical and semi-empirical potentials estimating approximate energetics and structures, (iv) use of DFT based quantum-chemical methods to ascertain the final optimal geometry and stability of the interface in question. We also demonstrate the flexibility and efficiency of our approach depending on the size of the investigated structures and size of the search space. The representative results from our search protocol will be presented for selected materials including semiconductors, transition metal systems, and oxides.

  17. Digital Alchemy for Materials Design: Colloids and Beyond

    NASA Astrophysics Data System (ADS)

    van Anders, Greg; Klotsa, Daphne; Karas, Andrew; Dodd, Paul; Glotzer, Sharon

    Starting with the early alchemists, a holy grail of science has been to make desired materials by manipulating basic building blocks. Building blocks that show promise for assembling new complex materials can be synthesized at the nanoscale with attributes that would astonish the ancient alchemists in their versatility. However, this versatility means that connecting building-block attributes to bulk structure is both necessary for rationally engineering materials and difficult because building block attributes can be altered in many ways. We show how to exploit the malleability of colloidal nanoparticle ``elements'' to quantitatively link building-block attributes to bulk structure through a statistical thermodynamic framework we term ``digital alchemy''. We use this framework to optimize building blocks for a given target structure and to determine which building-block attributes are most important to control for self-assembly, through a set of novel thermodynamic response functions. We thereby establish direct links between the attributes of colloidal building blocks and the bulk structures they form. Moreover, our results give concrete solutions to the more general conceptual challenge of optimizing emergent behaviors in nature and can be applied to other types of matter.

  18. Digital Alchemy for Materials Design: Colloids and Beyond.

    PubMed

    van Anders, Greg; Klotsa, Daphne; Karas, Andrew S; Dodd, Paul M; Glotzer, Sharon C

    2015-10-27

    Starting with the early alchemists, a holy grail of science has been to make desired materials by modifying the attributes of basic building blocks. Building blocks that show promise for assembling new complex materials can be synthesized at the nanoscale with attributes that would astonish the ancient alchemists in their versatility. However, this versatility means that making a direct connection between building-block attributes and bulk structure is both necessary for rationally engineering materials and difficult because building block attributes can be altered in many ways. Here we show how to exploit the malleability of the valence of colloidal nanoparticle "elements" to directly and quantitatively link building-block attributes to bulk structure through a statistical thermodynamic framework we term "digital alchemy". We use this framework to optimize building blocks for a given target structure and to determine which building-block attributes are most important to control for self-assembly, through a set of novel thermodynamic response functions, moduli, and susceptibilities. We thereby establish direct links between the attributes of colloidal building blocks and the bulk structures they form. Moreover, our results give concrete solutions to the more general conceptual challenge of optimizing emergent behaviors in nature and can be applied to other types of matter. As examples, we apply digital alchemy to systems of truncated tetrahedra, rhombic dodecahedra, and isotropically interacting spheres that self-assemble diamond, fcc, and icosahedral quasicrystal structures, respectively. Although our focus is on colloidal systems, our methods generalize to any building blocks with adjustable interactions. PMID:26401754

  19. Digital Alchemy for Materials Design: Colloids and Beyond.

    PubMed

    van Anders, Greg; Klotsa, Daphne; Karas, Andrew S; Dodd, Paul M; Glotzer, Sharon C

    2015-10-27

    Starting with the early alchemists, a holy grail of science has been to make desired materials by modifying the attributes of basic building blocks. Building blocks that show promise for assembling new complex materials can be synthesized at the nanoscale with attributes that would astonish the ancient alchemists in their versatility. However, this versatility means that making a direct connection between building-block attributes and bulk structure is both necessary for rationally engineering materials and difficult because building block attributes can be altered in many ways. Here we show how to exploit the malleability of the valence of colloidal nanoparticle "elements" to directly and quantitatively link building-block attributes to bulk structure through a statistical thermodynamic framework we term "digital alchemy". We use this framework to optimize building blocks for a given target structure and to determine which building-block attributes are most important to control for self-assembly, through a set of novel thermodynamic response functions, moduli, and susceptibilities. We thereby establish direct links between the attributes of colloidal building blocks and the bulk structures they form. Moreover, our results give concrete solutions to the more general conceptual challenge of optimizing emergent behaviors in nature and can be applied to other types of matter. As examples, we apply digital alchemy to systems of truncated tetrahedra, rhombic dodecahedra, and isotropically interacting spheres that self-assemble diamond, fcc, and icosahedral quasicrystal structures, respectively. Although our focus is on colloidal systems, our methods generalize to any building blocks with adjustable interactions.

  20. First Materials Science Research Facility Rack Capabilities and Design Features

    NASA Technical Reports Server (NTRS)

    Cobb, S.; Higgins, D.; Kitchens, L.; Curreri, Peter (Technical Monitor)

    2002-01-01

    The first Materials Science Research Rack (MSRR-1) is the primary facility for U.S. sponsored materials science research on the International Space Station. MSRR-1 is contained in an International Standard Payload Rack (ISPR) equipped with the Active Rack Isolation System (ARIS) for the best possible microgravity environment. MSRR-1 will accommodate dual Experiment Modules and provide simultaneous on-orbit processing operations capability. The first Experiment Module for the MSRR-1, the Materials Science Laboratory (MSL), is an international cooperative activity between NASA's Marshall Space Flight Center (MSFC) and the European Space Agency's (ESA) European Space Research and Technology Center (ESTEC). The MSL Experiment Module will accommodate several on-orbit exchangeable experiment-specific Module Inserts which provide distinct thermal processing capabilities. Module Inserts currently planned for the MSL are a Quench Module Insert, Low Gradient Furnace, and a Solidification with Quench Furnace. The second Experiment Module for the MSRR-1 configuration is a commercial device supplied by MSFC's Space Products Development (SPD) Group. Transparent furnace assemblies include capabilities for vapor transport processes and annealing of glass fiber preforms. This Experiment Module is replaceable on-orbit. This paper will describe facility capabilities, schedule to flight and research opportunities.

  1. Design elements for the development of cancer education print materials for a Latina/o audience.

    PubMed

    Buki, Lydia P; Salazar, Silvia I; Pitton, Viviana O

    2009-10-01

    Health educators can help reduce cancer disparities in Latino populations through the creation of effective print materials. In this effort, the National Cancer Institute conducted a comprehensive needs assessment to identify key design elements of cancer education programs and create a cost-effective process that would ensure consistency in the development of materials. This article introduces the Checklist of Design Elements for the Development of Cancer Education Print Materials for Latina/o Audiences (CEMLA), which includes a total of 10 design elements related to the process of developing materials and content. Using social learning theory as a theoretical framework, design elements are included that reflect cultural sensitivity at the surface and deep structure levels. This is the most comprehensive effort to date to integrate and synthesize theory and application in the design of materials for this audience.

  2. Elementary Students' Learning of Materials Science Practices through Instruction Based on Engineering Design Tasks

    ERIC Educational Resources Information Center

    Wendell, Kristen Bethke; Lee, Hee-Sun

    2010-01-01

    Materials science, which entails the practices of selecting, testing, and characterizing materials, is an important discipline within the study of matter. This paper examines how third grade students' materials science performance changes over the course of instruction based on an engineering design challenge. We conducted a case study of nine…

  3. 7 CFR 1717.605 - Design standards, plans and specifications, construction standards, and RUS accepted materials.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., construction standards, and RUS accepted materials. 1717.605 Section 1717.605 Agriculture Regulations of the... standards, plans and specifications, construction standards, and RUS accepted materials. All borrowers... system design, construction standards, and the use of RUS accepted materials. Borrowers must comply...

  4. Materials design and processings for industrial high-strain-rate superplastic forming

    SciTech Connect

    Hosokawa, H.; Higashi, K.

    2000-07-01

    The optimum materials design in microstructural control could be developed for the high-strain-rate superplastic materials in the industrial scale. In the present work, it is reported that the high-performance-engine pistons with near-net-shape can be fabricated by the superplastic forging technology in the high-strain-rate superplastic PM Al-Si based alloy, which is produced by using this optimum materials design.

  5. Robotic Materials Handling in Space: Mechanical Design of the Robot Operated Materials Processing System HitchHiker Experiment

    NASA Technical Reports Server (NTRS)

    Voellmer, George

    1997-01-01

    The Goddard Space Flight Center has developed the Robot Operated Materials Processing System (ROMPS) that flew aboard STS-64 in September, 1994. The ROMPS robot transported pallets containing wafers of different materials from their storage racks to a furnace for thermal processing. A system of tapered guides and compliant springs was designed to deal with the potential misalignments. The robot and all the sample pallets were locked down for launch and landing. The design of the passive lockdown system, and the interplay between it and the alignment system are presented.

  6. Virtual Welded - Joint Design Integrating Advanced Materials and Processing Technology

    SciTech Connect

    Yang, Zhishang; Ludewig, Howard W.; Babu, S. Suresh

    2005-06-30

    Virtual Welede-Joint Design, a systematic modeling approach, has been developed in this project to predict the relationship of welding process, microstructure, properties, residual stress, and the ultimate weld fatique strength. This systematic modeling approach was applied in the welding of high strength steel. A special welding wire was developed in this project to introduce compressive residual stress at weld toe. The results from both modeling and experiments demonstrated that more than 10x fatique life improvement can be acheived in high strength steel welds by the combination of compressive residual stress from the special welding wire and the desired weld bead shape from a unique welding process. The results indicate a technology breakthrough in the design of lightweight and high fatique performance welded structures using high strength steels.

  7. Designing nacre-like materials for simultaneous stiffness, strength and toughness: Optimum materials, composition, microstructure and size

    NASA Astrophysics Data System (ADS)

    Barthelat, Francois

    2014-12-01

    Nacre, bone and spider silk are staggered composites where inclusions of high aspect ratio reinforce a softer matrix. Such staggered composites have emerged through natural selection as the best configuration to produce stiffness, strength and toughness simultaneously. As a result, these remarkable materials are increasingly serving as model for synthetic composites with unusual and attractive performance. While several models have been developed to predict basic properties for biological and bio-inspired staggered composites, the designer is still left to struggle with finding optimum parameters. Unresolved issues include choosing optimum properties for inclusions and matrix, and resolving the contradictory effects of certain design variables. Here we overcome these difficulties with a multi-objective optimization for simultaneous high stiffness, strength and energy absorption in staggered composites. Our optimization scheme includes material properties for inclusions and matrix as design variables. This process reveals new guidelines, for example the staggered microstructure is only advantageous if the tablets are at least five times stronger than the interfaces, and only if high volume concentrations of tablets are used. We finally compile the results into a step-by-step optimization procedure which can be applied for the design of any type of high-performance staggered composite and at any length scale. The procedure produces optimum designs which are consistent with the materials and microstructure of natural nacre, confirming that this natural material is indeed optimized for mechanical performance.

  8. Decoupling interrelated parameters for designing high performance thermoelectric materials.

    PubMed

    Xiao, Chong; Li, Zhou; Li, Kun; Huang, Pengcheng; Xie, Yi

    2014-04-15

    The world's supply of fossil fuels is quickly being exhausted, and the impact of their overuse is contributing to both climate change and global political unrest. In order to help solve these escalating problems, scientists must find a way to either replace combustion engines or reduce their use. Thermoelectric materials have attracted widespread research interest because of their potential applications as clean and renewable energy sources. They are reliable, lightweight, robust, and environmentally friendly and can reversibly convert between heat and electricity. However, after decades of development, the energy conversion efficiency of thermoelectric devices has been hovering around 10%. This is far below the theoretical predictions, mainly due to the interdependence and coupling between electrical and thermal parameters, which are strongly interrelated through the electronic structure of the materials. Therefore, any strategy that balances or decouples these parameters, in addition to optimizing the materials' intrinsic electronic structure, should be critical to the development of thermoelectric technology. In this Account, we discuss our recently developed strategies to decouple thermoelectric parameters for the synergistic optimization of electrical and thermal transport. We first highlight the phase transition, which is accompanied by an abrupt change of electrical transport, such as with a metal-insulator and semiconductor-superionic conductor transition. This should be a universal and effective strategy to optimize the thermoelectric performance, which takes advantage of modulated electronic structure and critical scattering across phase transitions to decouple the power factor and thermal conductivity. We propose that solid-solution homojunction nanoplates with disordered lattices are promising thermoelectric materials to meet the "phonon glass electron crystal" approach. The formation of a solid solution, coupled with homojunctions, allows for

  9. Photovoltaic Module Encapsulation Design and Materials Selection, Volume 1, Abridged

    NASA Technical Reports Server (NTRS)

    Cuddihy, E. F.

    1982-01-01

    A summary version of Volume 1, presenting the basic encapsulation systems, their purposes and requirements, and the characteristics of the most promising candidate systems and materials, as identified and evaluated by the Flat-Plate Solar Array Project is presented. In this summary version considerable detail and much supporting and experimental information has necessarily been omitted. A reader interested in references and literature citations, and in more detailed information on specific topics, should consult Reference 1, JPL Document No. 5101-177, JPL Publication 81-102, DOE/JPL-1012-60 (JPL), June 1, 1982.

  10. Bridging the Design-Manufacturing-Materials Data Gap: Material Properties for Optimum Design and Manufacturing Performance in Light Vehicle Steel-Intensive Body Structures

    NASA Astrophysics Data System (ADS)

    Zuidema, Blake K.

    2012-09-01

    As safety and fuel economy regulations become increasingly more challenging around the world, light vehicle manufacturers are facing increasing pressure to reduce the weight of their vehicles cost effectively while maintaining or improving safety performance. Optimum light vehicle steel body structure weight and performance are achieved when the constraints of design, manufacturing, and material properties are considered simultaneously. ArcelorMittal has invested heavily over the past several years to close the gap between material property knowledge and the inter-relation between material performance and design and manufacturing efficiency. Knowledge gained through this process is presented and the importance of achieving this simultaneous 3-way optimization is illustrated by a lightweight steel door design example from ArcelorMittal's S-in motion catalog of lightweight steel solutions.

  11. Rational Design of Molecular Ferroelectric Materials and Nanostructures

    SciTech Connect

    Ducharme, Stephen

    2012-09-25

    The purpose of this project was to gain insight into the properties of molecular ferroelectrics through the detailed study of oligomer analogs of polyvinylidene fluoride (PVDF). By focusing on interactions at both the molecular level and the nanoscale level, we expect to gain improved understanding about the fundamental mechanism of ferroelectricity and its key properties. The research consisted of three complementary components: 1) Rational synthesis of VDF oligomers by Prof. Takacs' group; 2) Detailed structural and electrical studies of thin by Prof. Ducharme's Group; and 3) First-principles computational studies by DOE Lab Partner Dr. Serge Nakhman-son at Argonne National Laboratory. The main results of the work was a detailed understanding of the relationships between the molecular interactions and macroscopic phenomenology of fer-roelectricity VDF oligomers. This is valuable information supporting the development of im-proved electromechanical materials for, e.g., sonar, ultrasonic imaging, artificial muscles, and compliant actuators. Other potential applications include nonvolatile ferroelectric memories, heat-sensing imaging arrays, photovoltaic devices, and functional biomimetic materials. The pro-ject contributed to the training and professional development of undergraduate students and graduate students, post-doctoral assistants, and a high-school teacher. Project personnel took part in several outreach and education activities each year.

  12. Master's Degree Learners' Use of Theory in Designing Instructional Materials

    ERIC Educational Resources Information Center

    Wojtecki, John A.

    2012-01-01

    Educational institutions offering a master's degree program in instructional design incorporate instructional design theory into the master's degree course offerings. The responsibility for the student is to develop coursework. Master's degree learners will use instructional design theory to develop course materials. This study…

  13. First principles materials design of novel functional oxides

    NASA Astrophysics Data System (ADS)

    Cooper, Valentino R.; Voas, Brian K.; Bridges, Craig A.; Morris, James R.; Beckman, Scott P.

    2016-05-01

    We review our efforts to develop and implement robust computational approaches for exploring phase stability to facilitate the prediction-to-synthesis process of novel functional oxides. These efforts focus on a synergy between (i) electronic structure calculations for properties predictions, (ii) phenomenological/empirical methods for examining phase stability as related to both phase segregation and temperature-dependent transitions and (iii) experimental validation through synthesis and characterization. We illustrate this philosophy by examining an inaugural study that seeks to discover novel functional oxides with high piezoelectric responses. Our results show progress towards developing a framework through which solid solutions can be studied to predict materials with enhanced properties that can be synthesized and remain active under device relevant conditions.

  14. First principles materials design of novel functional oxides

    DOE PAGESBeta

    Cooper, Valentino R.; Voas, Brian K.; Bridges, Craig A.; Morris, James R.; Beckman, Scott P.

    2016-05-31

    We review our efforts to develop and implement robust computational approaches for exploring phase stability to facilitate the prediction-to-synthesis process of novel functional oxides. These efforts focus on a synergy between (i) electronic structure calculations for properties predictions, (ii) phenomenological/empirical methods for examining phase stability as related to both phase segregation and temperature-dependent transitions and (iii) experimental validation through synthesis and characterization. We illustrate this philosophy by examining an inaugural study that seeks to discover novel functional oxides with high piezoelectric responses. Lastly, our results show progress towards developing a framework through which solid solutions can be studied to predictmore » materials with enhanced properties that can be synthesized and remain active under device relevant conditions.« less

  15. Molecular Designs for Enhancement of Polarity in Ferroelectric Soft Materials

    NASA Astrophysics Data System (ADS)

    Ohtani, Ryo; Nakaya, Manabu; Ohmagari, Hitomi; Nakamura, Masaaki; Ohta, Kazuchika; Lindoy, Leonard F.; Hayami, Shinya

    2015-11-01

    The racemic oxovanadium(IV) salmmen complexes, [VO((rac)-(4-X-salmmen))] (X = C12C10C5 (1), C16 (2), and C18 (3); salmmen = N,N‧-monomethylenebis-salicylideneimine) with “banana shaped” molecular structures were synthesized, and their ferroelectric properties were investigated. These complexes exhibit well-defined hysteresis loops in their viscous phases, moreover, 1 also displays liquid crystal behaviour. We observed a synergetic effect influenced by three structural aspects; the methyl substituents on the ethylene backbone, the banana shaped structure and the square pyramidal metal cores all play an important role in generating the observed ferroelectricity, pointing the way to a useful strategy for the creation of advanced ferroelectric soft materials.

  16. Molecular Designs for Enhancement of Polarity in Ferroelectric Soft Materials

    PubMed Central

    Ohtani, Ryo; Nakaya, Manabu; Ohmagari, Hitomi; Nakamura, Masaaki; Ohta, Kazuchika; Lindoy, Leonard F.; Hayami, Shinya

    2015-01-01

    The racemic oxovanadium(IV) salmmen complexes, [VO((rac)-(4-X-salmmen))] (X = C12C10C5 (1), C16 (2), and C18 (3); salmmen = N,N′-monomethylenebis-salicylideneimine) with “banana shaped” molecular structures were synthesized, and their ferroelectric properties were investigated. These complexes exhibit well-defined hysteresis loops in their viscous phases, moreover, 1 also displays liquid crystal behaviour. We observed a synergetic effect influenced by three structural aspects; the methyl substituents on the ethylene backbone, the banana shaped structure and the square pyramidal metal cores all play an important role in generating the observed ferroelectricity, pointing the way to a useful strategy for the creation of advanced ferroelectric soft materials. PMID:26568045

  17. Computational design of materials for solar hydrogen generation

    NASA Astrophysics Data System (ADS)

    Umezawa, Naoto

    Photocatalysis has a great potential for the production of hydrogen from aquerous solution under solar light. In this talk, two different approaches toward the computational materials desing for solar hydrogen generation will be presented. Tin (Sn), which has two major oxidation states, Sn2+ and Sn4+, is abundant on the earth's crust. Recently, visible-light responsive photocatalytc H2 evolution reaction was identified over a mixed valence tin oxide Sn3O4. We have carried out crystal structure prediction for mixed valence tin oxides in different atomic compositions under ambient pressure condition using advanced computational methods based on the evolutionary crystal-structure search and density-functional theory. The predicted novel crystal structures realize the desirable band gaps and band edge positions for H2 evolution under visible light irradiation. It is concluded that multivalent tin oxides have a great potential as an abundant, cheap and environmentally-benign solar-energy conversion photofunctional materials. Transition metal doping is effective for sensitizing SrTiO3 under visible light. We have theoretically investigated the roles of the doped Cr in STO based on hybrid density-functional calculations. Cr atoms are preferably substituting for Ti under any equilibrium growth conditions. The lower oxidation state Cr3+, which is stabilized under an n-type condition of STO, is found to be advantageous for the photocatalytic performance. It is firther predicted that lanthanum is the best codopant for stabilizing the favorable oxidation state, Cr3+. The prediction was validated by our experiments that La and Cr co-doped STO shows the best performance among examined samples. This work was supported by the Japan Science and Technology Agency (JST) Precursory Research for Embryonic Science and Technology (PRESTO) and International Research Fellow program of Japan Society for the Promotion of Science (JSPS) through project P14207.

  18. An advanced microcomputer design for processing of semiconductor materials

    NASA Technical Reports Server (NTRS)

    Bjoern, L.; Lindkvist, L.; Zaar, J.

    1988-01-01

    In the Get Away Special 330 payload two germanium samples doped with gallium will be processed. The aim of the experiments is to create a planar solid/liquid interface, and to study the breakdown of this interface as the crystal growth rate increases. For the experiments a gradient furnace was designed which is heated by resistive heaters. Cooling is provided by circulating gas from the atmosphere in the cannister through cooling channels in the furnace. The temperature along the sample are measured by platinum/rhodium thermocouples. The furnace is controlled by a microcomputer system, based upon the processor 80C88. A data acquisition system is integrated into the system. In order to synchronize the different actions in time, a multitask manager is used.

  19. Effects of Buckling Knockdown Factor, Internal Pressure and Material on the Design of Stiffened Cylinders

    NASA Technical Reports Server (NTRS)

    Lovejoy, Andrew E.; Hilburger, Mark W.; Chunchu, Prasad B.

    2010-01-01

    A design study was conducted to investigate the effect shell buckling knockdown factor (SBKF), internal pressure and aluminum alloy material selection on the structural weight of stiffened cylindrical shells. Two structural optimization codes were used for the design study to determine the optimum minimum-weight design for a series of design cases, and included an in-house developed genetic algorithm (GA) code and PANDA2. Each design case specified a unique set of geometry, material, knockdown factor combinations and loads. The resulting designs were examined and compared to determine the effects of SBKF, internal pressure and material selection on the acreage design weight and controlling failure mode. This design study shows that use of less conservative SBKF values, including internal pressure, and proper selection of material alloy can result in significant weight savings for stiffened cylinders. In particular, buckling-critical cylinders with integrally machined stiffener construction can benefit from the use of thicker plate material that enables taller stiffeners, even when the stiffness, strength and density properties of these materials appear to be inferior.

  20. Plutonium Immobilization Material Characterization: Milestone 1 Report - Initiate Design of Prototype Material Characterization System

    SciTech Connect

    Bannochie, C.J.

    1999-06-01

    The objective of this task is to analyze impure oxide materials exiting from front-end processing prior to storage for feed blending. There are three goals to be accomplished with this task: reduce reblending (currently projected at 7% with an optimized ordering of the incoming material streams), determine if impure feed prep operations are performing adequately, and reduce plant operating costs by replacing wet prep elemental analyses whether conducted in the immobilization facility or in existing laboratories. An additional potential application is the analysis of blended oxide prior to first-stage UO{sub 2} and precursor addition.

  1. Accelerated materials design of fast oxygen ionic conductors based on first principles calculations

    NASA Astrophysics Data System (ADS)

    He, Xingfeng; Mo, Yifei

    Over the past decades, significant research efforts have been dedicated to seeking fast oxygen ion conductor materials, which have important technological applications in electrochemical devices such as solid oxide fuel cells, oxygen separation membranes, and sensors. Recently, Na0.5Bi0.5TiO3 (NBT) was reported as a new family of fast oxygen ionic conductor. We will present our first principles computation study aims to understand the O diffusion mechanisms in the NBT material and to design this material with enhanced oxygen ionic conductivity. Using the NBT materials as an example, we demonstrate the computation capability to evaluate the phase stability, chemical stability, and ionic diffusion of the ionic conductor materials. We reveal the effects of local atomistic configurations and dopants on oxygen diffusion and identify the intrinsic limiting factors in increasing the ionic conductivity of the NBT materials. Novel doping strategies were predicted and demonstrated by the first principles calculations. In particular, the K doped NBT compound achieved good phase stability and an order of magnitude increase in oxygen ionic conductivity of up to 0.1 S cm-1 at 900 K compared to the experimental Mg doped compositions. Our results provide new avenues for the future design of the NBT materials and demonstrate the accelerated design of new ionic conductor materials based on first principles techniques. This computation methodology and workflow can be applied to the materials design of any (e.g. Li +, Na +) fast ion-conducting materials.

  2. Design and synthesis of inorganic/organic hybrid electrochemical materials

    NASA Astrophysics Data System (ADS)

    Harreld, John H.

    An ambient pressure method for drying sol-gel materials is developed to synthesize high porosity (80--90%), high surface area vanadium oxide and silica aerogel materials (150--300 and 1000 m2/g for vanadium pentoxide and silica, respectively). The synthesis approach uses liquid exchange to replace the pore fluid with a low surface tension, nonpolar solvent which reduces the capillary pressures developed during drying. The Good-Girifalco interaction parameter is used to calculate pore stresses resulting from drying silica gels from various liquids. Vanadium oxide/polypyrrole hybrid aerogels are prepared using three strategies. These approaches focus on either sequential or consecutive polymerization of the inorganic and organic networks. Microcomposite aerogels are synthesized by encapsulating a dispersion of preformed polypyrrole in a vanadium pentoxide gel. In the second approach, pyrrole is polymerized and doped within the pore volume of preformed vanadium pentoxide gel. When the inorganic and organic precursors are polymerized simultaneously, the resulting gels exhibited a nanometer scaled microstructure with homogeneous distributions of either phases. Through this route, a suitable microstructure and composition for a lithium secondary battery cathode is obtained. Lithiated aerogels of hydrated nickel, cobalt, and mixed nickel-cobalt oxides are synthesized from lithium hydroxide and transition metal acetate precursors. The XRD analyses indicate that the nickel containing gels exhibit a lithium deficiency (less than 1 Li/transition metal. By increasing the concentration of the lithium precursor the lithium content in nickel oxides is increased, and additional base solution is no longer required to catalyze gelation. A non-hydrolytic sol-gel approach is utilized to create tin oxide and tin-aluminum binary oxide aerogels with high porosity (90%) and high surface area (300 m2/g). XRD data from single phase tin oxide aerogel indicates the growth of SnO2 crystallites

  3. The influence of material and design on total knee replacement wear.

    PubMed

    Essner, Aaron; Herrera, Lizeth; Hughes, Phillip; Kester, Mark

    2011-03-01

    It is difficult for surgeons to make the decision on which design or material to use given the different options available. Marketing claims and direct-to-consumer advertising certainly complicate this further. One company may claim a higher percentage of wear reduction with their bearing surfaces compared with those of another manufacturer. If the percentage of wear reduction is lower, it is unclear as to whether this creates a more effective technology for reducing wear in the clinical situation. The relative contribution and relationship of design and materials to wear performance must be considered before making that important judgment. To examine the overall influence of implant design on wear reduction, a knee simulator study was undertaken. This simulator study compared the Oxinium Genesis II system with the Triathlon Conventional and Triathlon X3 knee systems under physiologic stair-climb loading and motion profiles. This allows a similar comparison of material effect within one design but also a global comparison across designs. Test results show the Triathlon Conventional and Triathlon X3 knee systems have superior wear resistance compared with that of the Genesis II Oxinium system under stair-climbing simulation. This finding indicates that implant design plays a more significant role in knee wear reduction than material. Although material technology may improve a given knee system's ability to wear, design geometry has a first-order effect and should be addressed before materials. This study represents an effort to differentiate design effect from two different approaches to material enhancement. The results of this study support the predominance of design in knee replacement wear performance. Ultimately, only clinical evidence such as published studies or outcomes reported in the available joint registries will establish whether any material or design can achieve a 30-year outcome. PMID:21618933

  4. Computational Design of Photovoltaic Materials with Self Organized Nano Structures

    NASA Astrophysics Data System (ADS)

    Sato, Kazunori; Katayama-Yoshida, Hiroshi

    2013-03-01

    Chalcopyrite and II-VI semiconductors, such as Cu(In, Ga)Se2, Cu2ZnSn(S, Se)4 and Cd(S, Te), are one of the most promising materials for low cost photovoltaic solar-cells. In this paper, based on first-principles calculations, we propose that self-organized nano-structures in these compounds will enhance the conversion efficiency. Our calculations are based on the KKR-CPA-LDA with the self-interaction correction. We also use VASP package for calculating mixing energy and effective interactions of the systems by using the cluster expansion method. For phase separating systems, we simulate nano-structure formation by using the Monte Carlo method. It is expected that the photo-generated electron-hole pairs are efficiently separated by the type-II interface and then effectively transferred along the quasi-one-dimensional structures. Moreover, we can expect multiplication of generated carriers due to the multi-exciton effects in nano-structures.

  5. Design of a curvature sensor using a flexoelectric material

    NASA Astrophysics Data System (ADS)

    Yan, X.; Huang, W. B.; Kwon, S. R.; Yang, S. R.; Jiang, X. N.; Yuan, F. G.

    2013-04-01

    A curvature sensor based on flexoelectricity using Ba0.64Sr0.36TiO3 (BST) material is proposed and developed in this paper. The working principle of the sensor is based on the flexoelectricity, exhibiting coupling between mechanical strain gradient and electric polarization. A BST curvature sensor is lab prepared using a conventional solid state processing method. The curvature sensing is demonstrated in four point bending tests of the beam under harmonic loads. BST sensors are attached on both side surfaces of an aluminum beam, located symmetrically with respect to its neutral axis. Analyses have shown that the epoxy bonding layer plays a critical role for curvature transfer. Consequently a shear lag effect is taken into account for extracting actual curvature from the sensor measurement. Experimental results demonstrated good linearity from the charge outputs under the frequencies tests and showed a sensor sensitivity of 30.78pC•m in comparison with 32.48pC•m from theoretical prediction. The BST sensor provides a direct curvature measure instead of using traditional strain gage through interpolation and may offer an optional avenue for on-line and in-situ structural health monitoring.

  6. Life Modeling and Design Analysis for Ceramic Matrix Composite Materials

    NASA Technical Reports Server (NTRS)

    2005-01-01

    The primary research efforts focused on characterizing and modeling static failure, environmental durability, and creep-rupture behavior of two classes of ceramic matrix composites (CMC), silicon carbide fibers in a silicon carbide matrix (SiC/SiC) and carbon fibers in a silicon carbide matrix (C/SiC). An engineering life prediction model (Probabilistic Residual Strength model) has been developed specifically for CMCs. The model uses residual strength as the damage metric for evaluating remaining life and is posed probabilistically in order to account for the stochastic nature of the material s response. In support of the modeling effort, extensive testing of C/SiC in partial pressures of oxygen has been performed. This includes creep testing, tensile testing, half life and residual tensile strength testing. C/SiC is proposed for airframe and propulsion applications in advanced reusable launch vehicles. Figures 1 and 2 illustrate the models predictive capabilities as well as the manner in which experimental tests are being selected in such a manner as to ensure sufficient data is available to aid in model validation.

  7. Materials modeling by design: applications to amorphous solids.

    PubMed

    Biswas, Parthapratim; Tafen, D N; Inam, F; Cai, Bin; Drabold, D A

    2009-02-25

    In this paper, we review a host of methods used to model amorphous materials. We particularly describe methods which impose constraints on the models to ensure that the final model meets a priori requirements (on structure, topology, chemical order, etc). In particular, we review work based on quench from the melt simulations, the 'decorate and relax' method, which is shown to be a reliable scheme for forming models of certain binary glasses. A 'building block' approach is also suggested and yields a pleading model for GeSe(1.5). We also report on the nature of vulcanization in an Se network cross-linked by As, and indicate how introducing H into an a-Si network develops into a-Si:H. We also discuss explicitly constrained methods including reverse Monte Carlo (RMC) and a novel method called 'Experimentally Constrained Molecular Relaxation'. The latter merges the power of ab initio simulation with the ability to impose external information associated with RMC. PMID:21817359

  8. Materials modeling by design: applications to amorphous solids

    NASA Astrophysics Data System (ADS)

    Biswas, Parthapratim; Tafen, D. N.; Inam, F.; Cai, Bin; Drabold, D. A.

    2009-02-01

    In this paper, we review a host of methods used to model amorphous materials. We particularly describe methods which impose constraints on the models to ensure that the final model meets a priori requirements (on structure, topology, chemical order, etc). In particular, we review work based on quench from the melt simulations, the 'decorate and relax' method, which is shown to be a reliable scheme for forming models of certain binary glasses. A 'building block' approach is also suggested and yields a pleading model for GeSe1.5. We also report on the nature of vulcanization in an Se network cross-linked by As, and indicate how introducing H into an a-Si network develops into a-Si:H. We also discuss explicitly constrained methods including reverse Monte Carlo (RMC) and a novel method called 'Experimentally Constrained Molecular Relaxation'. The latter merges the power of ab initio simulation with the ability to impose external information associated with RMC.

  9. TOPICAL REVIEW: Rational design of organic electro-optic materials

    NASA Astrophysics Data System (ADS)

    Dalton, L. R.

    2003-05-01

    Quantum mechanical calculations are used to optimize the molecular first hyperpolarizability of organic chromophores and statistical mechanical calculations are used to optimize the translation of molecular hyperpolarizability to macroscopic electro-optic activity (to values of greater than 100 pm V-1 at telecommunications wavelengths). Macroscopic material architectures are implemented exploiting new concepts in nanoscale architectural engineering. Multi-chromophore-containing dendrimers and dendronized polymers not only permit optimization of electro-optic activity but also of auxiliary properties including optical loss (both absorption and scattering), thermal and photochemical stability and processability. New reactive ion etching and photolithographic techniques permit the fabrication of three-dimensional optical circuitry and the integration of that circuitry with semiconductor very-large-scale integration electronics and silica fibre optics. Electro-optic devices have been fabricated exploiting stripline, cascaded prism and microresonator device structures. Sub-1 V drive voltages and operational bandwidths of greater than 100 GHz have been demonstrated. Both single-and double-ring microresonators have been fabricated for applications such as active wavelength division multiplexing. Free spectral range values of 1 THz and per channel modulation bandwidths of 15 GHz have been realized permitting single-chip data rates of 500 Gb s-1. Other demonstrated devices include phased array radar, optical gyroscopes, acoustic spectrum analysers, ultrafast analog/digital converters and ultrahigh bandwidth signal generators.

  10. Ranking the stars: a refined Pareto approach to computational materials design.

    PubMed

    Lejaeghere, Kurt; Cottenier, Stefaan; Van Speybroeck, Veronique

    2013-08-16

    We propose a procedure to rank the most interesting solutions from high-throughput materials design studies. Such a tool is becoming indispensable due to the growing size of computational screening studies and the large number of criteria involved in realistic materials design. As a proof of principle, the binary tungsten alloys are screened for both large-weight and high-impact materials, as well as for fusion reactor applications. Moreover, the concept is generally applicable to any design problem where multiple competing criteria have to be optimized.

  11. Research Update: Towards designed functionalities in oxide-based electronic materials

    SciTech Connect

    Rondinelli, James M.; Poeppelmeier, Kenneth R.; Zunger, Alex

    2015-08-01

    One of the grand challenges facing materials-by-design approaches for complex oxide deployment in electronic devices is how to balance transformative first-principles based predictions with experimental feasibility. Here, we briefly review the functionality-driven approach (inverse design) for materials discovery, encapsulated in three modalities for materials discovery (m{sup 3}D) that integrate experimental feedback. We compare it to both traditional theoretical and high-throughput database-directed approaches aimed at advancing oxide-based materials into technologies.

  12. Materials study supporting thermochemical hydrogen cycle sulfuric acid decomposer design

    NASA Astrophysics Data System (ADS)

    Peck, Michael S.

    Increasing global climate change has been driven by greenhouse gases emissions originating from the combustion of fossil fuels. Clean burning hydrogen has the potential to replace much of the fossil fuels used today reducing the amount of greenhouse gases released into the atmosphere. The sulfur iodine and hybrid sulfur thermochemical cycles coupled with high temperature heat from advanced nuclear reactors have shown promise for economical large-scale hydrogen fuel stock production. Both of these cycles employ a step to decompose sulfuric acid to sulfur dioxide. This decomposition step occurs at high temperatures in the range of 825°C to 926°C dependent on the catalysis used. Successful commercial implementation of these technologies is dependent upon the development of suitable materials for use in the highly corrosive environments created by the decomposition products. Boron treated diamond film was a potential candidate for use in decomposer process equipment based on earlier studies concluding good oxidation resistance at elevated temperatures. However, little information was available relating the interactions of diamond and diamond films with sulfuric acid at temperatures greater than 350°C. A laboratory scale sulfuric acid decomposer simulator was constructed at the Nuclear Science and Engineering Institute at the University of Missouri-Columbia. The simulator was capable of producing the temperatures and corrosive environments that process equipment would be exposed to for industrialization of the sulfur iodide or hybrid sulfur thermochemical cycles. A series of boron treated synthetic diamonds were tested in the simulator to determine corrosion resistances and suitability for use in thermochemical process equipment. These studies were performed at twenty four hour durations at temperatures between 600°C to 926°C. Other materials, including natural diamond, synthetic diamond treated with titanium, silicon carbide, quartz, aluminum nitride, and Inconel

  13. Materials design and properties of nitride phosphors for LEDs

    NASA Astrophysics Data System (ADS)

    Schmidt, Peter; Tuecks, Andreas; Meyer, Joerg; Bechtel, Helmut; Wiechert, Detlef; Mueller-Mach, Regina; Mueller, Gerd; Schnick, Wolfgang

    2007-09-01

    We have studied structure-property relations of Eu(II) doped nitridosilicates M IISi 5N 8 and MSi 7N 10 (M = Sr, Ba). For both systems that are described as being efficient LED phosphors, we show that a detailed examination of the local activator environment in combination with net positive charge calculations for Eu with the EHTB-MO method allows a qualitative prediction of the luminescence properties of nitridosilicate LED phosphors. The non-linear shift of the amber to red emission of solid solutions Ba 2-xSr xSi 5N 8:Eu is explained by a non-statistical distribution of Eu over the available lattice sites. The Stokes shift differences between the two available Eu sites are significantly larger for Ba IISi 5N 8:Eu than for Sr IISi 5N 8:Eu. In contradiction to literature data, BaSi 7N 10:Eu shows emission in the cyan spectral region and a large Stokes shift, in accordance with the host lattice geometry and the electronic structure calculations that were carried out. SiAlON formation as an additional design tool to tune nitridosilicate phosphor emission properties is demonstrated for Sr IISi 5 -xAl xO xN 8-x:Eu. (Al,O) incorporation leads to anisotropic changes of lattice constants and a red shift and broadening of the Eu emission.

  14. Soft materials design via self assembly of functionalized icosahedral particles

    NASA Astrophysics Data System (ADS)

    Muthukumar, Vidyalakshmi Chockalingam

    In this work we simulate self assembly of icosahedral building blocks using a coarse grained model of the icosahedral capsid of virus 1m1c. With significant advancements in site-directed functionalization of these macromolecules [1], we propose possible application of such self-assembled materials for drug delivery. While there have been some reports on organization of viral particles in solution through functionalization, exploiting this behaviour for obtaining well-ordered stoichiometric structures has not yet been explored. Our work is in well agreement with the earlier simulation studies of icosahedral gold nanocrystals, giving chain like patterns [5] and also broadly in agreement with the wet lab works of Finn, M.G. et al., who have shown small predominantly chain-like aggregates with mannose-decorated Cowpea Mosaic Virus (CPMV) [22] and small two dimensional aggregates with oligonucleotide functionalization on the CPMV capsid [1]. To quantify the results of our Coarse Grained Molecular Dynamics Simulations I developed analysis routines in MATLAB using which we found the most preferable nearest neighbour distances (from the radial distribution function (RDF) calculations) for different lengths of the functional groups and under different implicit solvent conditions, and the most frequent coordination number for a virus particle (histogram plots further using the information from RDF). Visual inspection suggests that our results most likely span the low temperature limits explored in the works of Finn, M.G. et al., and show a good degree of agreement with the experimental results in [1] at an annealing temperature of 4°C. Our work also reveals the possibility of novel stoichiometric N-mer type aggregates which could be synthesized using these capsids with appropriate functionalization and solvent conditions.

  15. Perspective: NanoMine: A material genome approach for polymer nanocomposites analysis and design

    NASA Astrophysics Data System (ADS)

    Zhao, He; Li, Xiaolin; Zhang, Yichi; Schadler, Linda S.; Chen, Wei; Brinson, L. Catherine

    2016-05-01

    Polymer nanocomposites are a designer class of materials where nanoscale particles, functional chemistry, and polymer resin combine to provide materials with unprecedented combinations of physical properties. In this paper, we introduce NanoMine, a data-driven web-based platform for analysis and design of polymer nanocomposite systems under the material genome concept. This open data resource strives to curate experimental and computational data on nanocomposite processing, structure, and properties, as well as to provide analysis and modeling tools that leverage curated data for material property prediction and design. With a continuously expanding dataset and toolkit, NanoMine encourages community feedback and input to construct a sustainable infrastructure that benefits nanocomposite material research and development.

  16. The design and application of effective written instructional material: a review of published work

    PubMed Central

    Mayberry, John F

    2007-01-01

    This review will consider the evidence base for the format of educational material drawing on academic papers and the practice of the design industry. The core issues identified from the review are drawn together in guidelines for educational posters, text and web based material. The review deals with the design of written material both for use in leaflets and books as well as the impact of factors such as font type and size as well as colour on poster design. It sets these aspects of educational material within a research framework, which looks at impact on learning and subsequent change in practice. These issues are examined through a practical example of a poster designed for a regional gastroenterology meeting. PMID:17823226

  17. Design finalization and material qualification towards procurement of the ITER vacuum vessel

    NASA Astrophysics Data System (ADS)

    Ioki, K.; Barabash, V.; Bachmann, C.; Chappuis, P.; Choi, C. H.; Cordier, J.-J.; Giraud, B.; Gribov, Y.; Heitzenroeder, Ph.; Her, N.; Johnson, G.; Jones, L.; Jun, C.; Kim, B. C.; Kuzmin, E.; Loesser, D.; Martin, A.; Merola, M.; Pathak, H.; Readman, P.; Sugihara, M.; Terasawa, A.; Utin, Yu.; Wang, X.; Wu, S.; Yu, J.; ITER Organization; ITER Parties

    2011-10-01

    Procurement arrangements for ITER key components including the vacuum vessel (VV) have been signed and the ITER activities are now fully devoted towards construction. Final design reviews have been carried out for the main vessel and ports. One of the design review topics is the selection of materials, material procurement, and assessment of material performance during operation. The width of the inner shell splice plates was increased from 120 mm to 160 mm to minimize risk during the assembly of the Thermal shields and the VV. Instead of facet shaping, 3D shaping was introduced for the outboard inner shell. The material qualification procedures have been started for VV structural materials such as 316L(N) IG for licensing as a nuclear pressure equipment component. In accordance with the regulatory requirements and quality requirements for operation, common material specifications have been prepared in collaboration with the domestic agencies.

  18. Dedication to Degradation: The Beauty of Materials Designed to Lay in Ruin

    NASA Astrophysics Data System (ADS)

    Nychka, John A.; Kruzic, Jaime

    2014-04-01

    Degradation of materials is typically perceived to be a negative response in service. Many designs, and materials, have been and are ruined due to corrosion, fatigue, weathering, ultraviolet light, fungal attack, bacterial attack, erosion, wear, electromigration… and on the list goes. However, the carefully controlled and purposeful degradation of materials is a prerequisite for success for some designs—and such ability is a beautiful necessity when it comes to many regenerative biomaterials. In other instances, we must seek first to understand the degradation mechanisms before we can achieve degradation prevention—and the resistance of some materials to degradation is also beautiful. Regardless of whether we try to prevent or elicit degradation, our dedication to degradation of materials is ever present in materials design.

  19. Experimental design and theoretical analysis on the proof experiment of the inverse Doppler effect at optical frequencies

    NASA Astrophysics Data System (ADS)

    Jiang, Qiang; Liang, Binming; Hu, Aiqing

    2013-08-01

    The proof experiment of inverse Doppler effect is simulated by idealizing optical field distribution of laser as fundamental mode Gaussian beam. Two key factors, the detecting area and the angle from light to normal of detecting surface, are analyzed. The proof experiment conducted recently by our research team successfully shows that the experimental data are consistent with theoretical data. Our work lays a solid foundation for the design of experimental system and the coming experiments on the mechanism of inverse Doppler effect in negative index materials.

  20. Learning to Design and Analyze Materials Handling Systems: Developing Multimedia Tools

    ERIC Educational Resources Information Center

    Heragu, Sunderesh; Jennings, Sybillyn

    2003-01-01

    In this paper, we describe aspects related to learning and learning assessment including pedagogy, cognition, pilot study and results from the study. This study is conducted for an educational module on "10 Principles of Materials Handling". This module along with another on "Analysis and Design of Integrated Materials Handling Systems" constitute…

  1. An Annotated Bibliography of Materials Designed and Organized for Adult Use in Discussion Groups.

    ERIC Educational Resources Information Center

    Ellison, John W.

    This first annotated bibliography of materials designed and organized for adult use in disucssion groups includes both book and nonbook material. Areas dealt with are: art, censorship, change, child guidance, communication, crime, democracy, economics, education, evolution, food, foreign affairs, forgetting, generation gap, gold, good and evil,…

  2. Multimedia and Cognition: Examining the Effect of Applying Cognitive Principles to the Design of Instructional Materials

    ERIC Educational Resources Information Center

    Thompson, Nik; McGill, Tanya Jane

    2008-01-01

    The human cognitive system possesses a finite processing capacity, which is split into channels for various modalities, and learning can be inhibited if any of the cognitive channels is overloaded. However, although the amount of e-learning materials is increasing steadily, the design of instructional material has been largely based on intuition…

  3. 46 CFR 128.240 - Hydraulic or pneumatic power and control-materials and pressure design.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Hydraulic or pneumatic power and control-materials and... Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard piping component (such as pipe runs, fittings, flanges, and standard valves) for hydraulic or pneumatic power and...

  4. The Use of Schema Theory in the Design of Instructional Materials: A Physics Example.

    ERIC Educational Resources Information Center

    Hewson, Peter, W.; Posner, George J.

    1984-01-01

    Describes development of a generative schema based on the concept of change for inclusion in instructional materials for a college physics course to help students integrate all of the physics content. Psychological basis for these materials is discussed, a design approach is described, and questions are posed for further investigation. (MBR)

  5. 46 CFR 160.077-7 - Procedure for approval of design or material revision.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 6 2013-10-01 2013-10-01 false Procedure for approval of design or material revision. 160.077-7 Section 160.077-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Hybrid...

  6. 46 CFR 160.077-7 - Procedure for approval of design or material revision.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 6 2010-10-01 2010-10-01 false Procedure for approval of design or material revision. 160.077-7 Section 160.077-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Hybrid...

  7. 46 CFR 160.077-7 - Procedure for approval of design or material revision.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 6 2011-10-01 2011-10-01 false Procedure for approval of design or material revision. 160.077-7 Section 160.077-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Hybrid...

  8. 46 CFR 160.077-7 - Procedure for approval of design or material revision.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 6 2012-10-01 2012-10-01 false Procedure for approval of design or material revision. 160.077-7 Section 160.077-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Hybrid...

  9. 46 CFR 160.077-7 - Procedure for approval of design or material revision.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 6 2014-10-01 2014-10-01 false Procedure for approval of design or material revision. 160.077-7 Section 160.077-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT, CONSTRUCTION, AND MATERIALS: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Hybrid...

  10. Curriculum Design for Inquiry: Preservice Elementary Teachers' Mobilization and Adaptation of Science Curriculum Materials

    ERIC Educational Resources Information Center

    Forbes, Cory T.; Davis, Elizabeth A.

    2010-01-01

    Curriculum materials are crucial tools with which teachers engage students in science as inquiry. In order to use curriculum materials effectively, however, teachers must develop a robust capacity for pedagogical design, or the ability to mobilize a variety of personal and curricular resources to promote student learning. The purpose of this study…

  11. 46 CFR 128.240 - Hydraulic or pneumatic power and control-materials and pressure design.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Hydraulic or pneumatic power and control-materials and... Hydraulic or pneumatic power and control—materials and pressure design. (a) Each standard piping component (such as pipe runs, fittings, flanges, and standard valves) for hydraulic or pneumatic power and...

  12. Materials design considerations and selection for a large rad waste incinerator

    SciTech Connect

    Vormelker, P.R.; Jenkins, C.F.; Burns, H.H.

    1997-01-01

    A new incinerator has been built to process self-generated, low level radioactive wastes at the Department of Energy`s Savannah River Site. Wastes include protective clothing and other solid materials used during the handling of radioactive materials, and liquid chemical wastes resulting from chemical and waste management operations. The basic design and materials of construction selected to solve the anticipated corrosion problems from hot acidic gases are reviewed. Problems surfacing during trial runs prior to radioactive operations are discussed.

  13. James C. McGroddy Prize for New Materials Talk: From discovery to design of new materials

    NASA Astrophysics Data System (ADS)

    Kanatzidis, Mercouri G.

    The design and discovery of new materials and their crystal growth is critical for continued scientific and technological progress far into the future. It is also a fundamental goal of condense matter science. We have been developing the chemistry of novel chalcogenide and intermetallic materials which define a remarkably broad set of structurally diverse compounds, associated with a wide range of physical properties and impacting a variety of physics and materials science issues. In contrast to solid-state methods, materials syntheses in liquid fluxes permit crystallization at lower temperatures due to facile diffusion and possible chemical reactions with the flux itself. These reactions can produce a wide range of materials, often metastable such as oxides, chalcogenides and intermetallics, but typically the formation paths are obscure or poorly understood. In this talk I will describe how we observe, understand, and engineer the formation of compounds from inorganic melts and an approach we call ``panoramic synthesis''. I will also highlight some of our recent results on the discovery of remarkable materials and crystal structures and how they can be leveraged for achieving unusual or enhanced properties of interest in a variety of fields such as thermoelectrics, γ ray detection, superconductivity, topological properties, nonlinear optics, etc.

  14. 75 FR 19311 - Ocean Dumping; Guam Ocean Dredged Material Disposal Site Designation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-14

    ... for formal designation through rulemaking published in the Federal Register (FR). Formal designation..., wetland creation, habitat restoration, landfill daily cover, and recycling into commercial products such... at the site--no dumping of toxic materials or industrial or municipal waste would be allowed....

  15. 14 CFR 23.613 - Material strength properties and design values.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... statistical basis. (b) Design values must be chosen to minimize the probability of structural failure due to... must be shown by selecting design values that ensure material strength with the following probability... failure of which would result in loss of structural integrity of the component; 99 percent...

  16. Transformation optical design of a bending waveguide by use of isotropic materials.

    PubMed

    Wu, Xiaojiong; Lin, Zhifang; Chen, Huanyang; Chan, C T

    2009-11-01

    Based on the effective medium theory, we designed a simplified transformation media bending waveguide by use of only three kinds of isotropic material in an alternating layered structure. The design can be used to guide incoming waves smoothly along the bending part of a waveguide with slight distortions. Numerical simulations are performed to illustrate its functionality.

  17. Representing Clarity: Using Universal Design Principles to Create Effective Hybrid Course Learning Materials

    ERIC Educational Resources Information Center

    Spiegel, Cheri Lemieux

    2012-01-01

    This article describes how the author applied principles of universal design to hybrid course materials to increase student understanding and, ultimately, success. Pulling the three principles of universal design--consistency, color, and icon representation--into the author's Blackboard course allowed her to change the types of reading skills…

  18. 14 CFR 23.613 - Material strength properties and design values.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Material strength properties and design values. 23.613 Section 23.613 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction § 23.613...

  19. 14 CFR 23.613 - Material strength properties and design values.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Material strength properties and design values. 23.613 Section 23.613 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction § 23.613...

  20. Solid state photochemistry. Subpanel A-2(a): Design of molecular precursors for electronic materials

    SciTech Connect

    Wells, R.L.

    1996-09-01

    Recent achievements of synthetic chemistry in the field of electronic materials are presented in three categories; viz, precursor design for improved processing, new chemistry for selective growth, and new growth techniques. This is followed by a discussion of challenges and opportunities in two general areas designated as composition and structure, and growth and processing.

  1. Review of accelerator conceptual design for the International Fusion Materials Irradiation Facility (IFMIF)

    SciTech Connect

    Berwald, D.H.; Rathke, J.W.; Bruhwiler, D.L.

    1996-12-31

    A Conceptual Design Activity (CDA) for the International Fusion Materials Irradiation Facility (IFMIF) will be completed in December 1996. The IFMIF accelerator system, comprising two 125 mA, 40 MeV deuterium accelerators is a key element of the IFMIF facility. This paper describes the status of the accelerator design as of June, 1996. 7 refs., 3 figs., 1 tab.

  2. Study of materials for the design of MEMS capacitive pressure sensor

    NASA Astrophysics Data System (ADS)

    Jindal, Sumit Kumar; Raghuwanshi, Sanjeev Kumar

    2016-04-01

    Highly sensitive MEMS capacitive pressure sensor is nowadays used for many different applications such as aerospace, automobile, Bio-MEMS etc. This paper deals with study and comparison of different types of materials that can be used in design of MEMS capacitive pressure sensor. Initially principle and design of basic MEMS capacitive pressure sensor is explained. In the next section the properties of different materials is elaborated. The centre deflection of the diaphragm is calculated using COMSOL Multiphysics and Capacitance is calculated using MATLAB simulation. From the capacitance calculated sensitivity of the materials can be interpreted. The analysis is carried out for a pressure range of 0 to 0.1 MPa.

  3. First wall and blanket module safety enhancement by material selection and design decision

    SciTech Connect

    Merrill, B.J.

    1980-01-01

    A thermal/mechanical study has been performed which illustrates the behavior of a fusion reactor first wall and blanket module during a loss of coolant flow event. The relative safety advantages of various material and design options were determined. A generalized first wall-blanket concept was developed to provide the flexibility to vary the structural material (stainless steel vs titanium), coolant (helium vs water), and breeder material (liquid lithium vs solid lithium aluminate). In addition, independent vs common first wall-blanket cooling and coupled adjacent module cooling design options were included in the study. The comparative analyses were performed using a modified thermal analysis code to handle phase change problems.

  4. Big-deep-smart data in imaging for guiding materials design.

    PubMed

    Kalinin, Sergei V; Sumpter, Bobby G; Archibald, Richard K

    2015-10-01

    Harnessing big data, deep data, and smart data from state-of-the-art imaging might accelerate the design and realization of advanced functional materials. Here we discuss new opportunities in materials design enabled by the availability of big data in imaging and data analytics approaches, including their limitations, in material systems of practical interest. We specifically focus on how these tools might help realize new discoveries in a timely manner. Such methodologies are particularly appropriate to explore in light of continued improvements in atomistic imaging, modelling and data analytics methods.

  5. Effects of Materials Parameters and Design Details on the Fatigue of Composite Materials for Wind Turbine Blades

    SciTech Connect

    Mandell, J.F.; Samborsky, D.D.; Sutherland, H.J.

    1999-03-04

    This paper presents an analysis of the results of nine years of fatigue testing represented in the USDOE/Montana State University (DOE/MSU) Composite Materials Fatigue Database. The focus of the program has been to explore a broad range of glass-fiber-based materials parameters encompassing over 4500 data points for 130 materials systems. Significant trends and transitions in fatigue resistance are shown as the fiber content and fabric architecture are varied. The effects of structural details including ply drops, bonded stiffeners, and other geometries that produce local variations in fiber packing and geometry are also described. Fatigue tests on composite beam structures are then discussed; these show generally good correlation with coupon fatigue data in the database. Goodman diagrams for fatigue design are presented, and their application to predicting the service lifetime of blades is described.

  6. Application of the ASME code in designing containment vessels for packages used to transport radioactive materials

    SciTech Connect

    Raske, D.T.; Wang, Z.

    1992-07-01

    The primary concern governing the design of shipping packages containing radioactive materials is public safety during transport. When these shipments are within the regulatory jurisdiction of the US Department of Energy, the recommended design criterion for the primary containment vessel is either Section III or Section VIII, Division 1, of the ASME Boiler and Pressure Vessel Code, depending on the activity of the contents. The objective of this paper is to discuss the design of a prototypic containment vessel representative of a packaging for the transport of high-level radioactive material.

  7. Materials, Processes and Manufacturing in Ares 1 Upper Stage: Integration with Systems Design and Development

    NASA Technical Reports Server (NTRS)

    Bhat, Biliyar N.

    2008-01-01

    Ares I Crew Launch Vehicle Upper Stage is designed and developed based on sound systems engineering principles. Systems Engineering starts with Concept of Operations and Mission requirements, which in turn determine the launch system architecture and its performance requirements. The Ares I-Upper Stage is designed and developed to meet these requirements. Designers depend on the support from materials, processes and manufacturing during the design, development and verification of subsystems and components. The requirements relative to reliability, safety, operability and availability are also dependent on materials availability, characterization, process maturation and vendor support. This paper discusses the roles and responsibilities of materials and manufacturing engineering during the various phases of Ares IUS development, including design and analysis, hardware development, test and verification. Emphasis is placed how materials, processes and manufacturing support is integrated over the Upper Stage Project, both horizontally and vertically. In addition, the paper describes the approach used to ensure compliance with materials, processes, and manufacturing requirements during the project cycle, with focus on hardware systems design and development.

  8. Critical materials: a reason for sustainable education of industrial designers and engineers

    NASA Astrophysics Data System (ADS)

    Köhler, Andreas R.; Bakker, Conny; Peck, David

    2013-08-01

    Developed economies have become highly dependent on a range of technology metals with names such as neodymium and terbium. Stakeholders have warned of the impending scarcity of these critical materials. Difficulties in materials supply can affect the high-tech industries as well as the success of sustainable innovation strategies that are based on sophisticated technology. Industrial designers and engineers should therefore increase their awareness of the limits in availability of critical materials. In this paper, it is argued that materials' criticality can give a fresh impetus to the higher education of industrial design engineers. It is important to train future professionals to apply a systems perspective to the process of technology innovation, enabling them to thrive under circumstances of constrained material choices. The conclusions outline ideas on how to weave the topic into existing educational programmes of future technology developers.

  9. Manufacturing process and material selection in concurrent collaborative design of MEMS devices

    NASA Astrophysics Data System (ADS)

    Zha, Xuan F.; Du, H.

    2003-09-01

    In this paper we present knowledge of an intensive approach and system for selecting suitable manufacturing processes and materials for microelectromechanical systems (MEMS) devices in concurrent collaborative design environment. In the paper, fundamental issues on MEMS manufacturing process and material selection such as concurrent design framework, manufacturing process and material hierarchies, and selection strategy are first addressed. Then, a fuzzy decision support scheme for a multi-criteria decision-making problem is proposed for estimating, ranking and selecting possible manufacturing processes, materials and their combinations. A Web-based prototype advisory system for the MEMS manufacturing process and material selection, WebMEMS-MASS, is developed based on the client-knowledge server architecture and framework to help the designer find good processes and materials for MEMS devices. The system, as one of the important parts of an advanced simulation and modeling tool for MEMS design, is a concept level process and material selection tool, which can be used as a standalone application or a Java applet via the Web. The running sessions of the system are inter-linked with webpages of tutorials and reference pages to explain the facets, fabrication processes and material choices, and calculations and reasoning in selection are performed using process capability and material property data from a remote Web-based database and interactive knowledge base that can be maintained and updated via the Internet. The use of the developed system including operation scenario, use support, and integration with an MEMS collaborative design system is presented. Finally, an illustration example is provided.

  10. The Halogen Bond in the Design of Functional Supramolecular Materials: Recent Advances

    PubMed Central

    2013-01-01

    Halogen bonding is an emerging noncovalent interaction for constructing supramolecular assemblies. Though similar to the more familiar hydrogen bonding, four primary differences between these two interactions make halogen bonding a unique tool for molecular recognition and the design of functional materials. First, halogen bonds tend to be much more directional than (single) hydrogen bonds. Second, the interaction strength scales with the polarizability of the bond-donor atom, a feature that researchers can tune through single-atom mutation. In addition, halogen bonds are hydrophobic whereas hydrogen bonds are hydrophilic. Lastly, the size of the bond-donor atom (halogen) is significantly larger than hydrogen. As a result, halogen bonding provides supramolecular chemists with design tools that cannot be easily met with other types of noncovalent interactions and opens up unprecedented possibilities in the design of smart functional materials. This Account highlights the recent advances in the design of halogen-bond-based functional materials. Each of the unique features of halogen bonding, directionality, tunable interaction strength, hydrophobicity, and large donor atom size, makes a difference. Taking advantage of the hydrophobicity, researchers have designed small-size ion transporters. The large halogen atom size provided a platform for constructing all-organic light-emitting crystals that efficiently generate triplet electrons and have a high phosphorescence quantum yield. The tunable interaction strengths provide tools for understanding light-induced macroscopic motions in photoresponsive azobenzene-containing polymers, and the directionality renders halogen bonding useful in the design on functional supramolecular liquid crystals and gel-phase materials. Although halogen bond based functional materials design is still in its infancy, we foresee a bright future for this field. We expect that materials designed based on halogen bonding could lead to

  11. Meta-lens design with low permittivity dielectric materials through smart transformation optics

    NASA Astrophysics Data System (ADS)

    Kim, Junhyun; Shin, Dongheok; Choi, Seungjae; Yoo, Do-Sik; Seo, Ilsung; Kim, Kyoungsik

    2015-09-01

    We report here a design method based on smart transformation optics (STO) to control the range of the permittivity values of the materials required to manufacture transformation optics devices. In particular, we show that it is possible to reduce the maximum electric permittivity value required to realize a STO device with certain functionality by means of a simple conceptual elastic stretching process. We illustrate the design procedure with two types of collimator meta-lens designs, which we call warping space collimator meta-lens and half fisheye collimator meta-lens, respectively. We provide design examples of these two types of lenses with the help of COMSOL Multiphysics software. These two design examples are fabricated with commonly available dielectric materials by means of 3D printing technology. For the functional verification of these two collimator lenses, we provide measurement results obtained with transverse electric waves of frequency range 7-13GHz.

  12. Multiobjective control design including performance robustness for gust alleviation of a wing with adaptive material actuators

    NASA Astrophysics Data System (ADS)

    Layton, Jeffrey B.

    1997-06-01

    The goal of this paper is to examine the use of covariance control to directly design reduced-order multi-objective controllers for gust alleviation using adaptive materials as the control effector. It will use piezoelectric actuators as control effectors in a finite element model of a full-size wing model. More precisely, the finite element model is of the F-16 Agile Falcon/Active Flexible Wing that is modified to use piezoelectric actuators as control effectors. The paper will also examine the interacting roles of important control design constraints and objectives for designing an aeroservoelastic system. The paper will also present some results of multiobjective control design for the model, illustrating the benefits and complexity of modern practical control design for aeroservoelastic systems that use adaptive materials for actuation.

  13. Elementary Students' Learning of Materials Science Practices Through Instruction Based on Engineering Design Tasks

    NASA Astrophysics Data System (ADS)

    Wendell, Kristen Bethke; Lee, Hee-Sun

    2010-12-01

    Materials science, which entails the practices of selecting, testing, and characterizing materials, is an important discipline within the study of matter. This paper examines how third grade students' materials science performance changes over the course of instruction based on an engineering design challenge. We conducted a case study of nine students who participated in engineering design-based science instruction with the goal of constructing a stable, quiet, thermally comfortable model house. The learning outcome of materials science practices was assessed by clinical interviews conducted before and after the instruction, and the learning process was assessed by students' workbooks completed during the instruction. The interviews included two materials selection tasks for designing a sturdy stepstool and an insulated pet habitat. Results indicate that: (1) students significantly improved on both materials selection tasks, (2) their gains were significantly positively associated with the degree of completion of their workbooks, and (3) students who were highly engaged with the workbook's reflective record-keeping tasks showed the greatest improvement on the interviews. These findings suggest the important role workbooks can play in facilitating elementary students' learning of science through authentic activity such as engineering design.

  14. The effect of new priorities and new materials on residential refrigerator design

    SciTech Connect

    Benson, D.K.; Potter, T.F.

    1992-08-01

    Increasing energy-efficiency requirements, combined with environmental considerations, have resulted in designs for domestic refrigerators that incorporate new thermal insulating materials. The first series of tests of these materials have been sufficiently promising that incorporation of vacuum insulations if likely within the next several years. Initial designs will probably use a combination of vacuum insulations and foam; in future designs, major parts consolidation will be possible using structural and other characteristics of the new panel assemblies. Given optimization of the refrigerator thermal envelope according to life-cycle costs, energy use by refrigerators could be greatly reduced; refrigerators could lose their significance as a major component in residential energy-use. Possible forms in which these new materials will be used are discussed, including alternatives for composite assembly and requirements for reliability and durability.

  15. Study on Ply Orientation Optimum Design for Composite Material Structure Based on Genetic Algorithm

    NASA Astrophysics Data System (ADS)

    Liu, Lei; Ma, Ai-Jun

    2016-05-01

    To find the optimum design of ply orientation for composite material structure, we proposed a method based on genetic algorithm and executed on a composite frame case. Firstly we gave the descriptions of the structure including solid model and mechanical property of the material and then created the finite element model of composite frame and set a static load step to get the displacement of cared node. Then we created the optimization mathematical model and used genetic algorithm to find the global optimal solution of the optimization problem, and finally achieved the best layer angle of the composite material case. The ply orientation optimum design made a good performance as the results showed that the objective function dropped by 16.6%. This case can might provide a reference for ply orientation optimum design of similar composite structure.

  16. Analysis of the requirements on modern energetics and their impact on materials design

    NASA Astrophysics Data System (ADS)

    Foster, Joseph C., Jr.; Glumac, Nick; Stewart, D. Scott

    2012-03-01

    We characterized the "design" of explosive materials as represented by the complete suite of engineering specifications on ingredients and processes used in the manufacture of specific components used in various applications. The detonation of explosive materials and the associated high power density of this process have historically been accepted as essential elements of the design. Evolving requirements such as the desire for insensitive munitions and the broadened demands of controlling the power output are producing a new class on energetic materials whose thermo-chemical response to specific intentional trigger mechanisms result in reactive behavior far removed the classical detonation modeling represented by the physics and chemistry of Chapman-Jouguet [CJ] or Zel'dovich, VonNeuman, Doering [ZND] detonation models. Experimental studies of representative designs and analysis of the role of processes controlled by the mesostructure suggest functional paths to establishing the desired output.

  17. Analysis of the Requirements on Modern Energetics and Their Impact on Materials Design

    NASA Astrophysics Data System (ADS)

    Foster, Joseph C., Jr.; Glumac, Nick; Stewart, D. Scott

    2011-06-01

    We have characterized the ``design'' of explosive materials as represented by the complete suite of engineering specifications on ingredients and processes used in the manufacture of specific components used in various application. The detonation of explosive materials and the associated high power density of this process has historically been an essential element of the design. Evolving requirements such as the desire for insensitive munitions and broadened demands on the control of the power output are producing a new class on energetic materials whose thermo-chemical response to specific intentional trigger mechanisms result in reactive behavior far removed the classical detonation modeling represented by the physics and chemistry of Chapman-Jouguet [CJ] or Zel'dovich, VonNeuman, Doering [ZND] detonation model. Experimental studies of representative designs and analysis of the role of processes controlled by the mesostructure suggest functional paths to establishing the desired output.

  18. Rational Design of Diketopyrrolopyrrole-Based Small Molecules as Donating Materials for Organic Solar Cells

    PubMed Central

    Jin, Ruifa; Wang, Kai

    2015-01-01

    A series of diketopyrrolopyrrole-based small molecules have been designed to explore their optical, electronic, and charge transport properties as organic solar cell (OSCs) materials. The calculation results showed that the designed molecules can lower the band gap and extend the absorption spectrum towards longer wavelengths. The designed molecules own the large longest wavelength of absorption spectra, the oscillator strength, and absorption region values. The optical, electronic, and charge transport properties of the designed molecules are affected by the introduction of different π-bridges and end groups. We have also predicted the mobility of the designed molecule with the lowest total energies. Our results reveal that the designed molecules are expected to be promising candidates for OSC materials. Additionally, the designed molecules are expected to be promising candidates for electron and/or hole transport materials. On the basis of our results, we suggest that molecules under investigation are suitable donors for [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and its derivatives as acceptors of OSCs. PMID:26343640

  19. Rational Design of Diketopyrrolopyrrole-Based Small Moleculesas Donating Materials for Organic Solar Cells.

    PubMed

    Jin, Ruifa; Wang, Kai

    2015-01-01

    A series of diketopyrrolopyrrole-based small molecules have been designed to explore their optical, electronic, and charge transport properties as organic solar cell(OSCs) materials. The calculation results showed that the designed molecules can lower the band gap and extend the absorption spectrum towards longer wavelengths.The designed molecules own the large longest wavelength of absorption spectra,the oscillator strength, and absorption region values. The optical, electronic, and charge transport properties of the designed molecules are affected by the introduction of different π-bridges and end groups. We have also predicted the mobility of the designed molecule with the lowest total energies. Our results reveal that the designed molecules are expected to be promising candidates for OSC materials. Additionally, the designed molecules are expected to be promising candidates for electron and/or hole transport materials. On the basis of our results, we suggest that molecules under investigation are suitable donors for[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and its derivatives as acceptors of OSCs. PMID:26343640

  20. Rational Design of Diketopyrrolopyrrole-Based Small Moleculesas Donating Materials for Organic Solar Cells.

    PubMed

    Jin, Ruifa; Wang, Kai

    2015-08-27

    A series of diketopyrrolopyrrole-based small molecules have been designed to explore their optical, electronic, and charge transport properties as organic solar cell(OSCs) materials. The calculation results showed that the designed molecules can lower the band gap and extend the absorption spectrum towards longer wavelengths.The designed molecules own the large longest wavelength of absorption spectra,the oscillator strength, and absorption region values. The optical, electronic, and charge transport properties of the designed molecules are affected by the introduction of different π-bridges and end groups. We have also predicted the mobility of the designed molecule with the lowest total energies. Our results reveal that the designed molecules are expected to be promising candidates for OSC materials. Additionally, the designed molecules are expected to be promising candidates for electron and/or hole transport materials. On the basis of our results, we suggest that molecules under investigation are suitable donors for[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and its derivatives as acceptors of OSCs.

  1. Design of advanced porous graphene materials: from graphene nanomesh to 3D architectures.

    PubMed

    Jiang, Lili; Fan, Zhuangjun

    2014-02-21

    In order to make full utilization of the high intrinsic surface area of graphene, recently, porous graphene materials including graphene nanomesh, crumpled graphene and graphene foam, have attracted tremendous attention and research interest, owing to their exceptional porous structure (high surface area, and high pore volume) in combination with the inherent properties of graphene, such as high electronic conductivity, good thermal stability, and excellent mechanical strength. Interestingly, porous graphene materials and their derivatives have been explored in a wide range of applications in the fields of electronic and photonic devices, energy storage, gas separation/storage, oil absorption and sensors. This article reviews recent progress in the synthesis, characterization, properties, and applications of porous graphene materials. We aim to highlight the importance of designing different porous structures of graphene to meet future challenges, and the trend on future design of porous graphene materials is analyzed.

  2. Materials and mechanical design analysis of boron carbide reactor safety rods

    SciTech Connect

    Marra, J.C.

    1992-04-01

    The purpose of this task was to analyze the materials and mechanical design bases for the new boron carbide safety rod. These analyses included examination of the irradiation response of the materials, chemical compatibility of component materials, moisture considerations for the boron carbide pellets and susceptibility of the rod to corrosion under reactor environmental conditions. A number of issues concerning the mechanical behavior were also addressed. These included: safety rod dynamic response in scram scenarios, flexibility and mishandling behavior, and response to thermal excursions associated with gamma heating. A surveillance program aimed at evaluating the integrity of the safety rods following actual operating conditions and justifying life extension for the rods was also proposed. Based on the experimental testing and analyses associated with this task, it is concluded that the boron carbide safety rod design meets the materials and mechanical criteria for successful operational performance.

  3. Materials and mechanical design analysis of boron carbide reactor safety rods. Final report

    SciTech Connect

    Marra, J.C.

    1992-04-01

    The purpose of this task was to analyze the materials and mechanical design bases for the new boron carbide safety rod. These analyses included examination of the irradiation response of the materials, chemical compatibility of component materials, moisture considerations for the boron carbide pellets and susceptibility of the rod to corrosion under reactor environmental conditions. A number of issues concerning the mechanical behavior were also addressed. These included: safety rod dynamic response in scram scenarios, flexibility and mishandling behavior, and response to thermal excursions associated with gamma heating. A surveillance program aimed at evaluating the integrity of the safety rods following actual operating conditions and justifying life extension for the rods was also proposed. Based on the experimental testing and analyses associated with this task, it is concluded that the boron carbide safety rod design meets the materials and mechanical criteria for successful operational performance.

  4. Data mining for materials design: A computational study of single molecule magnet

    SciTech Connect

    Dam, Hieu Chi; Pham, Tien Lam; Ho, Tu Bao; Nguyen, Anh Tuan; Nguyen, Viet Cuong

    2014-01-28

    We develop a method that combines data mining and first principles calculation to guide the designing of distorted cubane Mn{sup 4+} Mn {sub 3}{sup 3+} single molecule magnets. The essential idea of the method is a process consisting of sparse regressions and cross-validation for analyzing calculated data of the materials. The method allows us to demonstrate that the exchange coupling between Mn{sup 4+} and Mn{sup 3+} ions can be predicted from the electronegativities of constituent ligands and the structural features of the molecule by a linear regression model with high accuracy. The relations between the structural features and magnetic properties of the materials are quantitatively and consistently evaluated and presented by a graph. We also discuss the properties of the materials and guide the material design basing on the obtained results.

  5. Design of advanced porous graphene materials: from graphene nanomesh to 3D architectures

    NASA Astrophysics Data System (ADS)

    Jiang, Lili; Fan, Zhuangjun

    2014-01-01

    In order to make full utilization of the high intrinsic surface area of graphene, recently, porous graphene materials including graphene nanomesh, crumpled graphene and graphene foam, have attracted tremendous attention and research interest, owing to their exceptional porous structure (high surface area, and high pore volume) in combination with the inherent properties of graphene, such as high electronic conductivity, good thermal stability, and excellent mechanical strength. Interestingly, porous graphene materials and their derivatives have been explored in a wide range of applications in the fields of electronic and photonic devices, energy storage, gas separation/storage, oil absorption and sensors. This article reviews recent progress in the synthesis, characterization, properties, and applications of porous graphene materials. We aim to highlight the importance of designing different porous structures of graphene to meet future challenges, and the trend on future design of porous graphene materials is analyzed.

  6. Bioactive ceramic-based materials with designed reactivity for bone tissue regeneration

    PubMed Central

    Ohtsuki, Chikara; Kamitakahara, Masanobu; Miyazaki, Toshiki

    2009-01-01

    Bioactive ceramics have been used clinically to repair bone defects owing to their biological affinity to living bone; i.e. the capability of direct bonding to living bone, their so-called bioactivity. However, currently available bioactive ceramics do not satisfy every clinical application. Therefore, the development of novel design of bioactive materials is necessary. Bioactive ceramics show osteoconduction by formation of biologically active bone-like apatite through chemical reaction of the ceramic surface with surrounding body fluid. Hence, the control of their chemical reactivity in body fluid is essential to developing novel bioactive materials as well as biodegradable materials. This paper reviews novel bioactive materials designed based on chemical reactivity in body fluid. PMID:19158015

  7. Electron work function-a promising guiding parameter for material design.

    PubMed

    Lu, Hao; Liu, Ziran; Yan, Xianguo; Li, Dongyang; Parent, Leo; Tian, Harry

    2016-04-14

    Using nickel added X70 steel as a sample material, we demonstrate that electron work function (EWF), which largely reflects the electron behavior of materials, could be used as a guide parameter for material modification or design. Adding Ni having a higher electron work function to X70 steel brings more "free" electrons to the steel, leading to increased overall work function, accompanied with enhanced e(-)-nuclei interactions or higher atomic bond strength. Young's modulus and hardness increase correspondingly. However, the free electron density and work function decrease as the Ni content is continuously increased, accompanied with the formation of a second phase, FeNi3, which is softer with a lower work function. The decrease in the overall work function corresponds to deterioration of the mechanical strength of the steel. It is expected that EWF, a simple but fundamental parameter, may lead to new methodologies or supplementary approaches for metallic materials design or tailoring on a feasible electronic base.

  8. Virtual Welded-Joint Design Integrating Advanced Materials and Processing Technologies

    SciTech Connect

    Yang, Z.; Dong, P.; Liu, S.; Babu, S.; Olson, G.; DebRoy, T.

    2005-04-15

    The primary goal of this project is to increase the fatigue life of a welded-joint by 10 times and to reduce energy use by 25% through product performance and productivity improvements using an integrated modeling approach. The fatigue strength of a welded-joint is currently the bottleneck to design high performance and lightweight welded structures using advanced materials such as high strength steels. In order to achieve high fatigue strength in a welded-joint it is necessary to manage the weld bead shape for lower stress concentration, produce preferable residual stress distribution, and obtain the desired microstructure for improved material toughness and strength. This is a systems challenge that requires the optimization of the welding process, the welding consumable, the base material, as well as the structure design. The concept of virtual welded-joint design has been proposed and established in this project. The goal of virtual welded-joint design is to develop a thorough procedure to predict the relationship of welding process, microstructure, property, residual stress, and the ultimate weld fatigue strength by a systematic modeling approach. The systematic approach combines five sub-models: weld thermal-fluid model, weld microstructure model, weld material property model, weld residual stress model, and weld fatigue model. The systematic approach is thus based on interdisciplinary applied sciences including heat transfer, computational fluid dynamics, materials science, engineering mechanics, and material fracture mechanics. The sub-models are based on existing models with further development. The results from modeling have been validated with critical experiments. The systematic modeling approach has been used to design high fatigue resistant welds considering the combined effects of weld bead geometry, residual stress, microstructure, and material property. In particular, a special welding wire has been developed in this project to introduce

  9. Materials and fractal designs for 3D multifunctional integumentary membranes with capabilities in cardiac electrotherapy.

    PubMed

    Xu, Lizhi; Gutbrod, Sarah R; Ma, Yinji; Petrossians, Artin; Liu, Yuhao; Webb, R Chad; Fan, Jonathan A; Yang, Zijian; Xu, Renxiao; Whalen, John J; Weiland, James D; Huang, Yonggang; Efimov, Igor R; Rogers, John A

    2015-03-11

    Advanced materials and fractal design concepts form the basis of a 3D conformal electronic platform with unique capabilities in cardiac electrotherapies. Fractal geometries, advanced electrode materials, and thin, elastomeric membranes yield a class of device capable of integration with the entire 3D surface of the heart, with unique operational capabilities in low power defibrillation. Co-integrated collections of sensors allow simultaneous monitoring of physiological responses. Animal experiments on Langendorff-perfused rabbit hearts demonstrate the key features of these systems.

  10. Materials and design experience in a slurry-fed electric glass melter

    SciTech Connect

    Barnes, S.M.; Larson, D.E.

    1981-08-01

    The design of a slurry-fed electric gas melter and an examination of the performance and condition of the construction materials were completed. The joule-heated, ceramic-lined melter was constructed to test the applicability of materials and processes for high-level waste vitrification. The developmental Liquid-Fed Ceramic Melter (LFCM) was operated for three years with simulated high-level waste and was subjected to conditions more severe than those expected for a nuclear waste vitrification plant.

  11. Stress distributions in maxillary central incisors restored with various types of post materials and designs.

    PubMed

    Madfa, A A; Kadir, M R Abdul; Kashani, J; Saidin, S; Sulaiman, E; Marhazlinda, J; Rahbari, R; Abdullah, B J J; Abdullah, H; Abu Kasim, N H

    2014-07-01

    Different dental post designs and materials affect the stability of restoration of a tooth. This study aimed to analyse and compare the stability of two shapes of dental posts (parallel-sided and tapered) made of five different materials (titanium, zirconia, carbon fibre and glass fibre) by investigating their stress transfer through the finite element (FE) method. Ten three-dimensional (3D) FE models of a maxillary central incisor restored with two different designs and five different materials were constructed. An oblique loading of 100 N was applied to each 3D model. Analyses along the centre of the post, the crown-cement/core and the post-cement/dentine interfaces were computed, and the means were calculated. One-way ANOVAs followed by post hoc tests were used to evaluate the effectiveness of the post materials and designs (p=0.05). For post designs, the tapered posts introduced significantly higher stress compared with the parallel-sided post (p<0.05), especially along the centre of the post. Of the materials, the highest level of stress was found for stainless steel, followed by zirconia, titanium, glass fibre and carbon fibre posts (p<0.05). The carbon and glass fibre posts reduced the stress distribution at the middle and apical part of the posts compared with the stainless steel, zirconia and titanium posts. The opposite results were observed at the crown-cement/core interface.

  12. Stress distributions in maxillary central incisors restored with various types of post materials and designs.

    PubMed

    Madfa, A A; Kadir, M R Abdul; Kashani, J; Saidin, S; Sulaiman, E; Marhazlinda, J; Rahbari, R; Abdullah, B J J; Abdullah, H; Abu Kasim, N H

    2014-07-01

    Different dental post designs and materials affect the stability of restoration of a tooth. This study aimed to analyse and compare the stability of two shapes of dental posts (parallel-sided and tapered) made of five different materials (titanium, zirconia, carbon fibre and glass fibre) by investigating their stress transfer through the finite element (FE) method. Ten three-dimensional (3D) FE models of a maxillary central incisor restored with two different designs and five different materials were constructed. An oblique loading of 100 N was applied to each 3D model. Analyses along the centre of the post, the crown-cement/core and the post-cement/dentine interfaces were computed, and the means were calculated. One-way ANOVAs followed by post hoc tests were used to evaluate the effectiveness of the post materials and designs (p=0.05). For post designs, the tapered posts introduced significantly higher stress compared with the parallel-sided post (p<0.05), especially along the centre of the post. Of the materials, the highest level of stress was found for stainless steel, followed by zirconia, titanium, glass fibre and carbon fibre posts (p<0.05). The carbon and glass fibre posts reduced the stress distribution at the middle and apical part of the posts compared with the stainless steel, zirconia and titanium posts. The opposite results were observed at the crown-cement/core interface. PMID:24834856

  13. Process Materialization Using Templates and Rules to Design Flexible Process Models

    NASA Astrophysics Data System (ADS)

    Kumar, Akhil; Yao, Wen

    The main idea in this paper is to show how flexible processes can be designed by combining generic process templates and business rules. We instantiate a process by applying rules to specific case data, and running a materialization algorithm. The customized process instance is then executed in an existing workflow engine. We present an architecture and also give an algorithm for process materialization. The rules are written in a logic-based language like Prolog. Our focus is on capturing deeper process knowledge and achieving a holistic approach to robust process design that encompasses control flow, resources and data, as well as makes it easier to accommodate changes to business policy.

  14. Covalent organic frameworks: a materials platform for structural and functional designs

    NASA Astrophysics Data System (ADS)

    Huang, Ning; Wang, Ping; Jiang, Donglin

    2016-10-01

    Covalent organic frameworks (COFs) are a class of crystalline porous polymer that allows the atomically precise integration of organic units into extended structures with periodic skeletons and ordered nanopores. One important feature of COFs is that they are designable; that is, the geometry and dimensions of the building blocks can be controlled to direct the topological evolution of structural periodicity. The diversity of building blocks and covalent linkage topology schemes make COFs an emerging materials platform for structural control and functional design. Indeed, COF architectures offer confined molecular spaces for the interplay of photons, excitons, electrons, holes, ions and guest molecules, thereby exhibiting unique properties and functions. In this Review, we summarize the major progress in the field of COFs and recent achievements in developing new design principles and synthetic strategies. We highlight cutting-edge functional designs and identify fundamental issues that need to be addressed in conjunction with future research directions from chemistry, physics and materials perspectives.

  15. Analysis of Photothermal Characterization of Layered Materials: Design of Optimal Experiments

    NASA Technical Reports Server (NTRS)

    Cole, Kevin D.

    2003-01-01

    In this paper numerical calculations are presented for the steady-periodic temperature in layered materials and functionally-graded materials to simulate photothermal methods for the measurement of thermal properties. No laboratory experiments were performed. The temperature is found from a new Green s function formulation which is particularly well-suited to machine calculation. The simulation method is verified by comparison with literature data for a layered material. The method is applied to a class of two-component functionally-graded materials and results for temperature and sensitivity coefficients are presented. An optimality criterion, based on the sensitivity coefficients, is used for choosing what experimental conditions will be needed for photothermal measurements to determine the spatial distribution of thermal properties. This method for optimal experiment design is completely general and may be applied to any photothermal technique and to any functionally-graded material.

  16. [Design and Preparation of Plant Bionic Materials Based on Optical and Infrared Features Simulation].

    PubMed

    Jiang, Xiao-jun; Lu, Xu-liang; Pan, Jia-liang; Zhang, Shuan-qin

    2015-07-01

    Due to the life characteristics such as physiological structure and transpiration, plants have unique optical and infrared features. In the optical band, because of the common effects of chlorophyll and water, plant leafs show spectral reflectance characteristics change in 550, 680, 1400 and 1900 nm significantly. In the infrared wave band, driven by transpiration, plants could regulate temperature on their own initiative, which make the infrared characteristics of plants different from artificial materials. So palnt bionic materials were proposed to simulate optical and infrared characteristics of plants. By analyzing formation mechanism of optical and infrared features about green plants, the component design and heat-transfer process of plants bionic materials were studied, above these the heat-transfer control formulation was established. Based on water adsorption/release compound, optical pigments and other man-made materials, plant bionic materials preparation methods were designed which could simulate the optical and infrared features of green plants. By chemical casting methods plant bionic material films were prepared, which use polyvinyl alcohol as film forming and water adsorption/release compound, and use optical pigments like chrome green and macromolecule yellow as colouring materials. The research conclusions achieved by testings figured out: water adsorption/release testing showed that the plant bionic materials with a certain thickness could absorb 1.3 kg water per square meter, which could satisfy the water usage of transpiration simulation one day; the optical and infrared simulated effect tests indicated that the plant bionic materials could preferably simulate the spectral reflective performance of green plants in optical wave band (380-2500 nm, expecially in 1400 and 1900 nm which were water absorption wave band of plants), and also it had similar daily infrared radiation variations with green plants, daily average radiation temperature

  17. [Design and Preparation of Plant Bionic Materials Based on Optical and Infrared Features Simulation].

    PubMed

    Jiang, Xiao-jun; Lu, Xu-liang; Pan, Jia-liang; Zhang, Shuan-qin

    2015-07-01

    Due to the life characteristics such as physiological structure and transpiration, plants have unique optical and infrared features. In the optical band, because of the common effects of chlorophyll and water, plant leafs show spectral reflectance characteristics change in 550, 680, 1400 and 1900 nm significantly. In the infrared wave band, driven by transpiration, plants could regulate temperature on their own initiative, which make the infrared characteristics of plants different from artificial materials. So palnt bionic materials were proposed to simulate optical and infrared characteristics of plants. By analyzing formation mechanism of optical and infrared features about green plants, the component design and heat-transfer process of plants bionic materials were studied, above these the heat-transfer control formulation was established. Based on water adsorption/release compound, optical pigments and other man-made materials, plant bionic materials preparation methods were designed which could simulate the optical and infrared features of green plants. By chemical casting methods plant bionic material films were prepared, which use polyvinyl alcohol as film forming and water adsorption/release compound, and use optical pigments like chrome green and macromolecule yellow as colouring materials. The research conclusions achieved by testings figured out: water adsorption/release testing showed that the plant bionic materials with a certain thickness could absorb 1.3 kg water per square meter, which could satisfy the water usage of transpiration simulation one day; the optical and infrared simulated effect tests indicated that the plant bionic materials could preferably simulate the spectral reflective performance of green plants in optical wave band (380-2500 nm, expecially in 1400 and 1900 nm which were water absorption wave band of plants), and also it had similar daily infrared radiation variations with green plants, daily average radiation temperature

  18. Advanced composites structural concepts and materials technologies for primary aircraft structures: Design/manufacturing concept assessment

    NASA Technical Reports Server (NTRS)

    Chu, Robert L.; Bayha, Tom D.; Davis, HU; Ingram, J. ED; Shukla, Jay G.

    1992-01-01

    Composite Wing and Fuselage Structural Design/Manufacturing Concepts have been developed and evaluated. Trade studies were performed to determine how well the concepts satisfy the program goals of 25 percent cost savings, 40 percent weight savings with aircraft resizing, and 50 percent part count reduction as compared to the aluminum Lockheed L-1011 baseline. The concepts developed using emerging technologies such as large scale resin transfer molding (RTM), automatic tow placed (ATP), braiding, out-of-autoclave and automated manufacturing processes for both thermoset and thermoplastic materials were evaluated for possible application in the design concepts. Trade studies were used to determine which concepts carry into the detailed design development subtask.

  19. Microwave Nondestructive Evaluation of Dielectric Materials with a Metamaterial Lens

    NASA Technical Reports Server (NTRS)

    Shreiber, Daniel; Gupta, Mool; Cravey, Robin L.

    2008-01-01

    A novel microwave Nondestructive Evaluation (NDE) sensor was developed in an attempt to increase the sensitivity of the microwave NDE method for detection of defects small relative to a wavelength. The sensor was designed on the basis of a negative index material (NIM) lens. Characterization of the lens was performed to determine its resonant frequency, index of refraction, focus spot size, and optimal focusing length (for proper sample location). A sub-wavelength spot size (3 dB) of 0.48 lambda was obtained. The proof of concept for the sensor was achieved when a fiberglass sample with a 3 mm diameter through hole (perpendicular to the propagation direction of the wave) was tested. The hole was successfully detected with an 8.2 cm wavelength electromagnetic wave. This method is able to detect a defect that is 0.037 lambda. This method has certain advantages over other far field and near field microwave NDE methods currently in use.

  20. Accelerating the design of solar thermal fuel materials through high throughput simulations.

    PubMed

    Liu, Yun; Grossman, Jeffrey C

    2014-12-10

    Solar thermal fuels (STF) store the energy of sunlight, which can then be released later in the form of heat, offering an emission-free and renewable solution for both solar energy conversion and storage. However, this approach is currently limited by the lack of low-cost materials with high energy density and high stability. In this Letter, we present an ab initio high-throughput computational approach to accelerate the design process and allow for searches over a broad class of materials. The high-throughput screening platform we have developed can run through large numbers of molecules composed of earth-abundant elements and identifies possible metastable structures of a given material. Corresponding isomerization enthalpies associated with the metastable structures are then computed. Using this high-throughput simulation approach, we have discovered molecular structures with high isomerization enthalpies that have the potential to be new candidates for high-energy density STF. We have also discovered physical principles to guide further STF materials design through structural analysis. More broadly, our results illustrate the potential of using high-throughput ab initio simulations to design materials that undergo targeted structural transitions.

  1. APPLICATION FO FLOW FORMING FOR USE IN RADIOACTIVE MATERIAL PACKAGING DESIGNS

    SciTech Connect

    Blanton, P.; Eberl, K.; Abramczyk, G.

    2012-07-11

    This paper reports on the development and testing performed to demonstrate the use of flow forming as an alternate method of manufacturing containment vessels for use in radioactive material shipping packaging designs. Additionally, ASME Boiler and Pressure Vessel Code, Section III, Subsection NB compliance along with the benefits compared to typical welding of containment vessels will be discussed. SRNL has completed fabrication development and the testing on flow formed containment vessels to demonstrate the use of flow forming as an alternate method of manufacturing a welded 6-inch diameter containment vessel currently used in the 9975 and 9977 radioactive material shipping packaging. Material testing and nondestructive evaluation of the flow formed parts demonstrate compliance to the minimum material requirements specified in applicable parts of ASME Boiler and Pressure Vessel Code, Section II. Destructive burst testing shows comparable results to that of a welded design. The benefits of flow forming as compared to typical welding of containment vessels are significant: dimensional control is improved due to no weld distortion; less final machining; weld fit-up issues associated with pipes and pipe caps are eliminated; post-weld non-destructive testing (i.e., radiography and die penetrant tests) is not necessary; and less fabrication steps are required. Results presented in this paper indicate some of the benefits in adapting flow forming to design of future radioactive material shipping packages containment vessels.

  2. Accelerating the Design of Solar Thermal Fuel Materials through High Throughput Simulations

    SciTech Connect

    Liu, Y; Grossman, JC

    2014-12-01

    Solar thermal fuels (STF) store the energy of sunlight, which can then be released later in the form of heat, offering an emission-free and renewable solution for both solar energy conversion and storage. However, this approach is currently limited by the lack of low-cost materials with high energy density and high stability. In this Letter, we present an ab initio high-throughput computational approach to accelerate the design process and allow for searches over a broad class of materials. The high-throughput screening platform we have developed can run through large numbers of molecules composed of earth-abundant elements and identifies possible metastable structures of a given material. Corresponding isomerization enthalpies associated with the metastable structures are then computed. Using this high-throughput simulation approach, we have discovered molecular structures with high isomerization enthalpies that have the potential to be new candidates for high-energy density STF. We have also discovered physical principles to guide further STF materials design through structural analysis. More broadly, our results illustrate the potential of using high-throughput ab initio simulations to design materials that undergo targeted structural transitions.

  3. Accelerating the design of solar thermal fuel materials through high throughput simulations.

    PubMed

    Liu, Yun; Grossman, Jeffrey C

    2014-12-10

    Solar thermal fuels (STF) store the energy of sunlight, which can then be released later in the form of heat, offering an emission-free and renewable solution for both solar energy conversion and storage. However, this approach is currently limited by the lack of low-cost materials with high energy density and high stability. In this Letter, we present an ab initio high-throughput computational approach to accelerate the design process and allow for searches over a broad class of materials. The high-throughput screening platform we have developed can run through large numbers of molecules composed of earth-abundant elements and identifies possible metastable structures of a given material. Corresponding isomerization enthalpies associated with the metastable structures are then computed. Using this high-throughput simulation approach, we have discovered molecular structures with high isomerization enthalpies that have the potential to be new candidates for high-energy density STF. We have also discovered physical principles to guide further STF materials design through structural analysis. More broadly, our results illustrate the potential of using high-throughput ab initio simulations to design materials that undergo targeted structural transitions. PMID:25372463

  4. Taguchi statistical design and analysis of cleaning methods for spacecraft materials

    NASA Technical Reports Server (NTRS)

    Lin, Y.; Chung, S.; Kazarians, G. A.; Blosiu, J. O.; Beaudet, R. A.; Quigley, M. S.; Kern, R. G.

    2003-01-01

    In this study, we have extensively tested various cleaning protocols. The variant parameters included the type and concentration of solvent, type of wipe, pretreatment conditions, and various rinsing systems. Taguchi statistical method was used to design and evaluate various cleaning conditions on ten common spacecraft materials.

  5. Evaluation of critical materials in five additional advance design photovoltaic cells

    SciTech Connect

    Smith, S.A.; Watts, R.L.; Martin, P.; Gurwell, W.E.

    1981-02-01

    The objective of this study is to identify potential material supply constraints due to the large-scale deployment of five advanced photovoltaic (PV) cell designs, and to suggest strategies to reduce the impacts of these production capacity limitations and potential future material shortages. The Critical Materials Assessment Program (CMAP) screens the designs and their supply chains and identifies potential shortages which might preclude large-scale use of the technologies. The results of the screening of five advanced PV cell designs are presented: (1) indium phosphide/cadmium sulfide, (2) zinc phosphide, (3) cadmium telluride/cadmium sulfide, (4) copper indium selenium, and (5) cadmium selenide photoelectrochemical. Each of these five cells is screened individually assuming that they first come online in 1991, and that 25 Gwe of peak capacity is online by the year 2000. A second computer screening assumes that each cell first comes online in 1991 and that each cell has a 5 GWe of peak capacity by the year 2000, so that the total online capacity for the five cells is 25 GWe. Based on a review of the preliminary baseline screening results, suggestions were made for varying such parameters as the layer thickness, cell production processes, etc. The resulting PV cell characterizations were then screened again by the CMAP computer code. The CMAP methodology used to identify critical materials is described; and detailed characterizations of the advanced photovoltaic cell designs under investigation, descriptions of additional cell production processes, and the results are presented. (WHK)

  6. Nickel cadmium cell designs negative to positive material ratio and precharge levels

    NASA Technical Reports Server (NTRS)

    Gross, S.

    1977-01-01

    A review is made of the factors affecting the choices of negative-to-positive materials ratio and negative precharge in nickel-cadmium cells. The effects of these variables on performance are given, and the different methods for setting precharge are evaluated. The effects of special operating requirements on the design are also discussed.

  7. Exploring the Effect of Materials Designed with Augmented Reality on Language Learners' Vocabulary Learning

    ERIC Educational Resources Information Center

    Solak, Ekrem; Cakir, Recep

    2015-01-01

    The purpose of this study was to determine the motivational level of the participants in a language classroom towards course materials designed in accordance with augmented reality technology and to identify the correlation between academic achievement and motivational level. 130 undergraduate students from a state-run university in Turkey…

  8. Improving Transfer of Learning through Designed Context-Based Instructional Materials

    ERIC Educational Resources Information Center

    Bahtaji, Michael Allan A.

    2015-01-01

    This study investigates the outcome of designed source-text materials in context-based physics learning using validated test questions in mechanics. Two groups of students received context-based instruction (experimental group) and one group received content-based instruction (control group). These three groups of students are only different with…

  9. Design Guidelines for the Development of Digital Nutrigenomics Learning Material for Heterogeneous Target Groups

    ERIC Educational Resources Information Center

    Busstra, Maria C.; Hartog, Rob; Kersten, Sander; Muller, Michael

    2007-01-01

    Nutritional genomics, or nutrigenomics, can be considered as the combination of molecular nutrition and genomics. Students who attend courses in nutrigenomics differ with respect to their prior knowledge. This study describes digital nutrigenomics learning material suitable for students from various backgrounds and provides design guidelines for…

  10. Materials and optimized designs for human-machine interfaces via epidermal electronics.

    PubMed

    Jeong, Jae-Woong; Yeo, Woon-Hong; Akhtar, Aadeel; Norton, James J S; Kwack, Young-Jin; Li, Shuo; Jung, Sung-Young; Su, Yewang; Lee, Woosik; Xia, Jing; Cheng, Huanyu; Huang, Yonggang; Choi, Woon-Seop; Bretl, Timothy; Rogers, John A

    2013-12-17

    Thin, soft, and elastic electronics with physical properties well matched to the epidermis can be conformally and robustly integrated with the skin. Materials and optimized designs for such devices are presented for surface electromyography (sEMG). The findings enable sEMG from wide ranging areas of the body. The measurements have quality sufficient for advanced forms of human-machine interface.

  11. 75 FR 54497 - Ocean Dumping; Guam Ocean Dredged Material Disposal Site Designation

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-08

    ... Register (FR). Historically, dredged material generated around Guam by the Navy and the Port Authority of... will, wherever feasible, designate ocean dumping sites beyond the edge of the continental shelf and... continental land mass and does not have a continental shelf. In the ] absence of a shelf break,...

  12. Instructional Design Considerations in Converting Non-CBT Materials into CBT Courses.

    ERIC Educational Resources Information Center

    Ng, Raymond

    Instructional designers who are asked to convert existing training materials into computer-based training (CBT) must take special precautions to avoid making the product into a sophisticated page turner. Although conversion may save considerable time on subject research and analysis, courses to be delivered through microcomputers may require…

  13. 30 CFR 27.20 - Quality of material, workmanship, and design.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Quality of material, workmanship, and design. 27.20 Section 27.20 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS METHANE-MONITORING SYSTEMS Construction and...

  14. 30 CFR 27.20 - Quality of material, workmanship, and design.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Quality of material, workmanship, and design. 27.20 Section 27.20 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS METHANE-MONITORING SYSTEMS Construction and...

  15. Investigating Bandgap Energies, Materials, and Design of Light-Emitting Diodes

    ERIC Educational Resources Information Center

    Wagner, Eugene P., II

    2016-01-01

    A student laboratory experiment to investigate the intrinsic and extrinsic bandgaps, dopant materials, and diode design in light-emitting diodes (LEDs) is presented. The LED intrinsic bandgap is determined by passing a small constant current through the diode and recording the junction voltage variation with temperature. A second visible…

  16. Design, Implementation, and Evaluation of GIS-Based Learning Materials in an Introductory Geoscience Course.

    ERIC Educational Resources Information Center

    Hall-Wallace, Michelle K.; McAuliffe, Carla M.

    2002-01-01

    Investigates student learning that occurred with a Geographic Information Systems (GIS) based module on plate tectonics and geologic hazards. Examines factors in the design and implementation of the materials that impacted student learning. Reports positive correlations between student' spatial ability and performance. Includes 17 references.…

  17. Graphic Design: A Sustainable Solution to Manage the Contents of Teaching Materials

    ERIC Educational Resources Information Center

    Victor, Garcia Izaguirre; Luisa, Pier Castello Maria; Eduardo, Arvizu Sanchez

    2010-01-01

    There is a concern that the teaching of subjects is applied not only with support from a set of technological devices, but largely in the proper use of teaching and new technologies. Taking this idea, the authors develop a research and sustainable design that result in educational materials in solid content and technological innovation, also to…

  18. Wiki-Based Rapid Prototyping for Teaching-Material Design in E-Learning Grids

    ERIC Educational Resources Information Center

    Shih, Wen-Chung; Tseng, Shian-Shyong; Yang, Chao-Tung

    2008-01-01

    Grid computing environments with abundant resources can support innovative e-Learning applications, and are promising platforms for e-Learning. To support individualized and adaptive learning, teachers are encouraged to develop various teaching materials according to different requirements. However, traditional methodologies for designing teaching…

  19. Color Research and Its Application to the Design of Instructional Materials.

    ERIC Educational Resources Information Center

    Pett, Dennis; Wilson, Trudy

    1996-01-01

    Reviews color research and considers its implications for the design of instructional materials. Topics include physiological and psychological effects; color and learning, including attention, search tasks, retention and other objective measures, and non-objective measures; color and the cathode ray tube (CRT); and further research needs.…

  20. Design for Cataloging Non-Book Materials: Adaptable to Computer Use.

    ERIC Educational Resources Information Center

    Genesee Valley School Development Association, Rochester, NY.

    This design was developed in response to a need for cataloging non-book materials compatible to schools in a nine-county region. Cataloging procedures are outlined for charts, disc recordings, filmloops, filmstrips, flash cards, games, kits, maps and globes, picture slides, audio and video tapes, and transparencies. (AB)