A lower limit for the grain size of nanocrystalline solids obtained by crystallization of the glass and its dependency on the crystallization temperature are thermodynamically considered. It is found that the nanocrystalline materials have the smallest grain size when the crystallization temperature is roughly half of the melting temperature. At this temperature, the Gibbs free energy differenc...

Below the melting temperature Tm, crystals are the stable phase of typical elemental or molecular systems. However, cooling down a liquid below Tm, crystallization is anything but inevitable. The liquid can be supercooled, eventually forming a glass below the glass transition temperature Tg. Despite their long lifetimes and the presence of strong barriers that produces an apparent stability, su...

The asymmetric unit of the solvated title salt, 2C(3)H(7)N(6) (+)·C(4)H(4)O(4) (2-)·C(4)H(6)O(4)·2H(2)O, contains one essentially planar melaminium (2,4,6-triamino-1,3,5-triazin-1-ium) cation (r.m.s. deviation of the non-H atoms = 0.0097 Å), one-half of a succinate anion, one-half of a succinic acid solvent mol-ecule and one water molecule of crystallization; full mol-ecules are generated by in...

The structure of the title compound, (C7H10N)4[H2V10O28]·2H2O, was solved from a non-merohedrally twinned crystal (ratio of twin components ∼0.6:0.4). The asymmetric unit consists of one-half deca-vanadate anion (the other half completed by inversion symmetry), two 2,6-di-methyl-pyridinium cations and one water mol-ecule of crystallization. In the crystal, the components are connected by strong...

G protein-coupled receptors (GPCRs) represent the largest family of transmembrane signaling proteins and are the target of approximately half of all therapeutic agents. Agonist ligands bind their cognate GPCRs stabilizing the active conformation that is competent to bind G proteins, thus initiating a cascade of intracellular signaling events leading to modification of the cell activity. Despite...

To synthesize optically active 2-amino-2-methyl-3-phenylpropanoic acid (1), (RS)-2-benzoylamino-2-benzyl-3-hydroxypropanoic acid [(RS)-2] was first optically resolved using cinchonidine as a resolving agent to yield optically pure (S)- and (R)-2 in yields of about 70%, based on half of the starting amount of (RS)-2. Next, the racemic structure of (RS)-2 was examined based on melting point, solu...

The asymmetric unit of title hydrated salt, C22H46N4 (2+)·2Cl(-)·4H2O, comprises half a centrosymmetric dication, one Cl(-) anion and two water mol-ecules of crystallization. The structure determination reveals that protonation has occurred at diagonally opposite amine N atoms, and that the dication features intra-molecular N-H⋯N hydrogen bonds. In the crystal, a three-dimensional artchitecture...

Procedures for the isolation, purification, and crystallization of wheat germ agglutinin are described. The agglutinin was purified 184-fold to homogeneity from commercial wheat germ lipase. A molecular weight of 23,500 was estimated for the protein by means of sedimentation equilibrium and sodium dodecyl sulfate gel electrophoresis. The agghxtinin is a glycoprotein. Amino acid and carbohydrate...

Thin films of GeTe2 were deposited on glass substrates using radio-frequency magnetron sputtering with various hydrogen flow rates in the growth chamber. Transmission data of deposited films were taken and used to determine optical constants refractive index n , extinction coefficient , and absorption coefficient and the energies corresponding to absorption coefficients of 104 and 103 cm−1 E04,...

We have found that treatment of the photosynthetic membranes of green plants, or thylakoids, with the nonionic detergent Triton X-114 at a 10:1 ratio has three effects: (a) photosystem I and coupling factor are solubilized, so that the membranes retain only photosystem II (PS II) and its associated light-harvesting apparatus (LHC-II); (b) LHC-II is crystallized, and so is removed from its norma...