Entanglement Between Demand and Supply in Markets with Bandwagon Goods

Whenever customers’ choices (e.g. to buy or not a given good) depend on others choices (cases coined ‘positive externalities’ or ‘bandwagon effect’ in the economic literature), the demand may be multiply valued: for a same posted price, there is either a small number of buyers, or a large one—in which case one says that the customers coordinate. This leads to a dilemma for the seller: should he sell at a high price, targeting a small number of buyers, or at low price targeting a large number of buyers? In this paper we show that the interaction between demand and supply is even more complex than expected, leading to what we call the curse of coordination: the pricing strategy for the seller which aimed at maximizing his profit corresponds to posting a price which, not only assumes that the customers will coordinate, but also lies very near the critical price value at which such high demand no more exists. This is obtained by the detailed mathematical analysis of a particular model formally related to the Random Field Ising Model and to a model introduced in social sciences by T.C. Schelling in the 70’s.     

Multinuclear NMR spectra and GIAO/DFT calculations of N-benzylazoles and N-benzylbenzazoles

The ¹H, ¹³C, and ¹⁵N chemical shifts of almost the whole series of N-benzyl azoles and benzazoles, with the exception of the unknown 1-benzyl-1H-pentazole (10) and the very unstable 2-benzyl-2H-isoindole (12), have been measured. In addition, the X-ray crystal structure of 1-benzyl-1H-indazole (14) was solved (monoclinic, space group P2₁/n), its geometry being very close to that used for the calculations. The absolute chemical shieldings were calculated at the gauge-independent atomic orbital (GIAO)/Becke, 3-parameter, Lee-Yang-Parr (B3LYP)/6-311++G(d,p) level and then transformed with very robust empirical equations into chemical shifts of the three nuclei showing an excellent agreement with the 313 experimental values.

     

Biological and Medical Applications of Calcium Phosphate Nanoparticles

Calcium phosphate nanoparticles have a high biocompatibility and biodegradability due to their chemical similarity to human hard tissue, for example, bone and teeth. They can be used as efficient carriers for different kinds of biomolecules such as nucleic acids, proteins, peptides, antibodies, or drugs, which alone are not able to enter cells where their biological effect is required. They can be loaded with cargo molecules by incorporating them, unlike solid nanoparticles, and also by surface functionalization. This offers protection, for example, against nucleases, and the possibility for cell targeting. If such nanoparticles are functionalized with fluorescing dyes, they can be applied for imaging in vitro and in vivo. Synthesis, functionalization and cell uptake mechanisms of calcium phosphate nanoparticles are discussed together with applications in transfection, gene silencing, imaging, immunization, and bone substitution. Biodistribution data of calcium phosphate nanoparticles in vivo are reviewed.     

A new tetragonal structure type for Li2B2C

The ternary dilithium diboron carbide, Li₂B₂C (tetragonal, space group Pm2, tP10), crystallizes as a new structure type and consists of structural fragments which are typical for structures of elemental lithium and boron or binary borocarbide B₁₃C₂. The symmetries of the occupied sites are .m. and 2mm. for the B and C atoms, and m2 and 2mm. for the Li atoms. The coordination polyhedra around the Li atoms are cuboctahedra and 15‐vertex distorted pseudo‐Frank–Kasper polyhedra. The environment of the B atom is a ten‐vertex polyhedron. The nearest neighbours of the C atom are two B atoms, and this group is surrounded by a deformed cuboctahedron with one centred lateral facet. Electronic structure calculations using the TB–LMTO–ASA method reveal strong B...C and B...B interactions.     

Two-phase wacker oxidation of alkenes catalyzed by water-soluble macromolecular complexes of palladium

New water-soluble macromolecular palladium complexes with phase transfer ability were used for two-phase Wacker oxidation of higher alkenes. Macromolecular metal complexes have been prepared employing as ligands monobutyl ether of polyethylene oxide and copolymers of ethylene oxide and propylene oxide functionalized by β,β'-iminodipropionitrile and acetodinitrile. Macromolecular metal complexes exhibited high activity and selectivity as catalysts for Wacker oxidation of different alkenes: octene-1, dodecene-1, hexadecene-1, styrene, propenylbenzene, cyclooctadiene-1,5. The complexes based on β,β'-iminodipropionitrile ligands showed the highest activity. All catalysts can be easily separated from product and used repeatedly without decrease of activity.     

Photodissociation of hydrogen halide molecules on free ice nanoparticles

Photodissociation of water clusters doped with HX(X=Br,Cl), molecules has been studied in a molecular beam experiment. The HX(H2O)n clusters are dissociated with 193 nm laser pulses, and the H fragments are ionized at 243.07 nm and their time-of-flight distributions are measured. Experiments with deuterated species DBr(H2O)n and HBr(D2O)n suggest that the photodissociation signal originates from the presence of the HX molecule on the water cluster, but does not come directly from a photolysis of the HX molecule. The H fragment is proposed to originate from the hydronium molecule H3O. Possible mechanisms of the H3O production are discussed. Experimental evidence suggests that acidic dissociation takes place in the cluster, but the H3O+ ion remains rather immobile.     

Photophysical and electrochemical properties of the outer-sphere associate of [Ru(bipy)<Subscript>3</Subscript>]<Superscript>2+</Superscript> with <Emphasis Type="Italic">p</Emphasis>-sulfonatothiacalix[4]arene

¹H NMR titration and X-ray diffraction analysis revealed that [Ru(bipy)₃]²⁺ forms an outer-sphere inclusion complex with p-sulfonatothiacalix[4]arene in a ratio of 1: 1 in both aqueous solutions and the solid state. According to cyclic voltammograms and fluorimetric data, the outer-sphere association of [Ru(bipy)₃]²⁺ with p-sulfonatothiacalix[4]arene changes the reversible character of the electrochemical oxidation of [Ru(bipy)₃]²⁺ and lowers its emission intensity. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1863–1870, September, 2008.