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from article Affinity monolith chromatography

General format for producing a GMA/EDMA affinity monolith where the reactants are mixed and injected into a sealed column. Heating the reactant mixture within the column results in polymerization and column formation. After heating, the column is…

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from article Affinity monolith chromatography

(a) Representative chromatogram obtained for the fast analysis of human IgG on an affinity monolithic membrane containing immobilized protein A, where peak 1 represents nonretained components in a 10-fold diluted human serum sample and peak 2 is…

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from article Shape-memory polymers

Molecular mechanism of the thermally induced shape-memory effect of a polymer network Ttrans is the thermal transition temperature related to the switching phase. (Adapted from A. Lendlein and S. Kelch, Shape-memory polymers, Angew. Chem. Int. Ed.,…

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from article Shape-memory polymers

Magnetically induced shape-memory effect of a thermoplastic shape-memory composite from nanoparticles consisting of iron(III) oxide in a silica matrix and a poly(etherurethane) exposed to an alternating magnetic field (f = 258 kHz, H = 30 kA·m−1).…

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from article Shape-memory polymers

Series of photographs illustrating the triple-shape effect of an intelligent tube. The triple shape material is a polymer network containing poly(∊-caprolactone) segments and poly(ethylene glycol) side chains. The series shows the recovery of shapes…

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from article Electrospun polymer nanofibers

A typical setup for electrospinning. The inset shows the whipping process of a nanofiber during electrospinning, as captured using a high-speed camera. (Adapted from J. Xie et al., Electrospun nanofibers for neural tissue engineering, Nanoscale,…

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from article Electrospun polymer nanofibers

Scanning electron microscopy images showing electrospun nanofibers with different alignments. (a) A nonwoven mat of random nanofibers collected on a piece of aluminum foil. (b) A uniaxially aligned array of nanofibers deposited across a rectangular…

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from article Electrospun polymer nanofibers

Fluorescence micrograph revealing the aligned projection of neurites (green). The neurites can replicate the topography of the underlying nanofibers with a uniaxial alignment.

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from article Electrospun polymer nanofibers

Superimposed fluorescence and scanning electron micrographs showing the migration of cells from the periphery to the center, as guided by a scaffold of radially aligned nanofibers. (Adapted from J. Xie et al., Radially aligned electrospun nanofibers…

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from article Polymeric molecular magnets

The molecular linkers that hold polymeric molecular magnets together are typically neutral or anionic ligands. These molecules act as Lewis bases that form coordination bonds with Lewis acid transition-metal cations. Hybrid materials that possess…

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from article Polymeric molecular magnets

Polymeric molecular magnets are typically formed through solution techniques that involve combining solutions that contain cationic metal nodes with solutions of anionic or neutral ligands that act as molecular linkers. Crystals are typically grown…

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from article Polymeric molecular magnets

Dimensionalities of anionic dicyanamide polymeric molecular magnets. Metal nodes are illustrated as large balls and the 5-atom dicyanamide ligands. The nitrile nitrogen atoms of adjacent dicyanamide ligands that propagate the polymer are illustrated…

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from article Advanced batteries

Ragone plot of specific power density in W/kg versus specific energy density in Wh/kg of various electrochemical energy storage and conversion devices.

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from article Advanced batteries

Typical Li-ion cell indicating the processes occurring on charge.

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from article Advanced batteries

Steady-state charge curve of a Li-ion cell consisting of a graphite anode and a LiCoO2 cathode. The graph shows the half-cell potentials and the thermodynamic potentials for various side reactions.

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from article Hydrogen storage materials

Crystal structure of Li4BN3H10, illustrating BH4 and NH2 complexes.

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from article Two-photon absorption

Laser beam with various intensities demonstrating (a) localized excitation in 3D by two-photon excitation; (b) limited penetration depth of one-photon excitation in an absorbing medium; and (c) improved penetration depth through the use of…

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from article Two-photon absorption

Scanning laser exposure of a two-photon photopolymer resin 3D lithographic microfabrication.

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from article Two-photon absorption

Polymeric “stack-of-logs” photonic-bandgap-like structure made by 3D lithographic microfabrication. (a) Overall view; width of structure is comparable to that of a human hair. (b) Closeup side view showing 5-μm period.

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from article Phthalates in western Aleutian Island seabirds

Map of islands from which samples have been collected (2009–2014).

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from article Ultracold molecules

Schematic illustration of the temperature regimes (in a logarithmic scale) corresponding to the formation of cold and ultracold molecules compared to temperatures in normal and other extreme environments that exist nature.

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from article Ultracold molecules

Schematic illustrations of (a) a p-wave barrier in ultracold collisions, and (b) a barrierless reaction involving s-wave collisions. The intermolecular distance R and the interaction potential V(R) are in arbitrary units.

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from article Pulsar navigation

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from article Pulsar navigation

Crab Nebula and pulsar in the x-ray band, imaged by NASA's Chandra X-ray Observatory. (NASA, CXC, SAO)

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from article Pulsar navigation

ARGOS satellite with the USA experiment.

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from article Smart structures and materials

Futuristic intelligent bridge system.

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from article Smart structures and materials

Tubular transport system for goods. (Courtesy of William Vandersteel)

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from article Smart structures and materials

Dampers, (a) New York's World Trade Center, fitted with dampers. (b) Placement. (c) Damper. (3M Company)

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from article Nitrogen fixation reactions

Catalytic ammonia formation by a molybdenum-containing compound. R represents a large hydrocarbon group that protects the metal center. Electrons (e− from a reducing agent and protons (H+) from an acid are added to N2.

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from article Nitrogen fixation reactions

FeMoco, where molybdenum nitrogenase fixes N2. X is an unidentified atom (C, N, or O).

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from article Cyanocarbon

Reactions of tetracyanoethylene.

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from article Aircraft collision avoidance system

Surveillance with Mode A/C transponders. (Reprinted with permission of MIT Lincoln Laboratory, Lexington, MA)

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from article Aircraft collision avoidance system

TCAS pilot displays. (a) Traffic advisory (TA) display. (b) Vertical resolution advisory (RA) display. (Reprinted with permission of MIT Lincoln Laboratory)

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from article Laser photochemistry

Excitation scheme using intense infrared lasers. (a) Multiphoton. (b) Single photon. The black arrows represent the absorption of a photon.

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from article Laser photochemistry

Schematic representation of a photodissociation experiment where 210-nm light is used to excite bromoiodomethane, causing rupture of the strong C-Br bond in preference to the weaker C-I bond.

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from article Laser photochemistry

Schematic drawing of the reaction barrier for breaking either the O-H or the O-D bond in the reaction of H + HOD or Cl + HOD. The thick arrows represent vibrational overtone excitation of either the 4νOH or the 5νOD bonds of HOD. The thin arrows…

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from article Laser photochemistry

Mask repair by laser deposition using a low-power laser at 1-μm resolution. (After K. G. Ibbs and R. M. Osgood, eds., Laser Chemical Processing for Microelectronics, Cambridge University Press, 1989)

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from article Laser photochemistry

Diagram of the expansion of a gas in a supersonic jet. The gas cools as it expands into the low-pressure regions.

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from article Laser photochemistry

Potential energy diagram for the dissociation of ICN. (After A. H. Zewail, Chem. Eng. News, 66(42):24–42, 1988)

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from article Field theory (mathematics)

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from article Field theory (mathematics)

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from article Carbon

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from article Carbon

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from article Carbon

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from article Information theory (biology)

Human information processing. The estimates of channel capacity are based on the number of rods in the retina of the eye and the number of hair cells in the inner ear's organ of Corti.

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from article Information theory (biology)