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... selective adsorption properties which might be attributable to the interaction between H2 molecules and the framework by multiple contacts with aromatic rings or the small aperture of channels in 2, which discriminates H2 (kinetic diameter 2.8 Å) from N2 (kinetic diameter 3.64 Å). In conclusion, we ...
... selective adsorption properties which might be attributable to the interaction between H2 molecules and the framework by multiple contacts with aromatic rings or the small aperture of channels in 2, which discriminates H2 (kinetic diameter 2.8 Å) from N2 (kinetic diameter 3.64 Å). In conclusion, we ...
NOBLE-GAS CHEMISTRY
... The chemical bonds between noble gas and other atoms are usually quite fragile due to various redox (electron-transfer) reactions. In consequence of that, the exploration of noble-gas chemistry constitutes a very good probe of the capabilities offered by low-temperature experimental techniques and a ...
... The chemical bonds between noble gas and other atoms are usually quite fragile due to various redox (electron-transfer) reactions. In consequence of that, the exploration of noble-gas chemistry constitutes a very good probe of the capabilities offered by low-temperature experimental techniques and a ...
BalanceEquationsetc
... • A mole is defined as the number of atoms in exactly 12 grams of carbon- 12 • The number is called Avogadro’s Number • One mole of carbon atoms has a mass of 12 grams ...
... • A mole is defined as the number of atoms in exactly 12 grams of carbon- 12 • The number is called Avogadro’s Number • One mole of carbon atoms has a mass of 12 grams ...
Investigation of the Hysteretic Phenomena in Surface Reconstruction
... fundamentally important. For the growth of low-dimensional nano structures it is vital to know the growth kinetics of the process. The MBE growth can be observed in-situ by monitoring the surface condition of the crystal (i.e. the surface reconstruction) by Reflection High-Energy Electron Diffractio ...
... fundamentally important. For the growth of low-dimensional nano structures it is vital to know the growth kinetics of the process. The MBE growth can be observed in-situ by monitoring the surface condition of the crystal (i.e. the surface reconstruction) by Reflection High-Energy Electron Diffractio ...
Introduction to Organic Electronics
... Thermal motion of free carriers can be seen as random collision (scattering) of the free carriers with the crystal lattice. A random motion of an electron or hole leads to zero net displacement of the free carrier over a sufficient long distance / period of time. The average distance between two col ...
... Thermal motion of free carriers can be seen as random collision (scattering) of the free carriers with the crystal lattice. A random motion of an electron or hole leads to zero net displacement of the free carrier over a sufficient long distance / period of time. The average distance between two col ...
Topological studies of three related MOFs of Gd(III) and 5
... in MOF5). The SBUs thus act as connection points and have their own geometry and connectivity. They are generally rigid and the reproducibility of SBU formation under specific reaction conditions make them useful in synthesis planning (Rowsell & Yaghi, 2004; Yaghi et al., 2003). 5-nitroisophthalic a ...
... in MOF5). The SBUs thus act as connection points and have their own geometry and connectivity. They are generally rigid and the reproducibility of SBU formation under specific reaction conditions make them useful in synthesis planning (Rowsell & Yaghi, 2004; Yaghi et al., 2003). 5-nitroisophthalic a ...
3Basic Polymer Chemistry
... vinyl acetate contains more than one variety of monomer and is thus a copolymer. ...
... vinyl acetate contains more than one variety of monomer and is thus a copolymer. ...
Carboxypeptidase A - Chemistry Courses: About
... pocket once substrate or inhibitor is bound.16 Specificity toward the C-terminal carboxylgte of substrates is provided by hydrogen-bond interactions with a triad of residues: a salt link with the positively charged guanidinium moiety of Arg-145, a hydrogen bond donated from Tyr-248, and a hydrogen b ...
... pocket once substrate or inhibitor is bound.16 Specificity toward the C-terminal carboxylgte of substrates is provided by hydrogen-bond interactions with a triad of residues: a salt link with the positively charged guanidinium moiety of Arg-145, a hydrogen bond donated from Tyr-248, and a hydrogen b ...
Auger electron spectroscopic study of the oxidation of oxygen-saturated polycrystalline... by Ramazan Kahraman
... The surfaces developed in this study were analyzed by Auger Electron Spectroscopy (AES). AES, together with ion etching equipment (sputtering), was utilized to measure the stoichiometry, thickness and compositional depth profiles of the ZrO2 surface layers formed on oxygen-saturated zirconium substr ...
... The surfaces developed in this study were analyzed by Auger Electron Spectroscopy (AES). AES, together with ion etching equipment (sputtering), was utilized to measure the stoichiometry, thickness and compositional depth profiles of the ZrO2 surface layers formed on oxygen-saturated zirconium substr ...
Self-assembled monolayer
Self-assembled monolayers (SAM) of organic molecules are molecular assemblies formed spontaneously on surfaces by adsorption and are organized into more or less large ordered domains. In some cases molecules that form the monolayer do not interact strongly with the substrate. This is the case for instance of the two-dimensional supramolecular networks of e.g. Perylene-tetracarboxylicacid-dianhydride (PTCDA) on gold or of e.g. porphyrins on highly oriented pyrolitic graphite (HOPG). In other cases the molecules possess a head group that has a strong affinity to the substrate and anchors the molecule to it. Such a SAM consisting of a head group, tail and functional end group is depicted in Figure 1. Common head groups include thiols, silanes, phosphonates, etc.SAMs are created by the chemisorption of ""head groups"" onto a substrate from either the vapor or liquid phase followed by a slow organization of ""tail groups"". Initially, at small molecular density on the surface, adsorbate molecules form either a disordered mass of molecules or form an ordered two-dimensional ""lying down phase"", and at higher molecular coverage, over a period of minutes to hours, begin to form three-dimensional crystalline or semicrystalline structures on the substrate surface. The ""head groups"" assemble together on the substrate, while the tail groups assemble far from the substrate. Areas of close-packed molecules nucleate and grow until the surface of the substrate is covered in a single monolayer.Adsorbate molecules adsorb readily because they lower the surface free-energy of the substrate and are stable due to the strong chemisorption of the ""head groups."" These bonds create monolayers that are more stable than the physisorbed bonds of Langmuir–Blodgett films. A Trichlorosilane based ""head group"", for example in a FDTS molecule reacts with an hydroxyl group on a substrate, and forms very stable, covalent bond [R-Si-O-substrate] with an energy of 452 kJ/mol. Thiol-metal bonds, that are on the order of 100 kJ/mol, making the bond a fairly stable in a variety of temperature, solvents, and potentials. The monolayer packs tightly due to van der Waals interactions, thereby reducing its own free energy. The adsorption can be described by the Langmuir adsorption isotherm if lateral interactions are neglected. If they cannot be neglected, the adsorption is better described by the Frumkin isotherm.