Valence characteristics and entry of a third party

This paper offers an explanation for the discrepancy between Downs' prediction of convergence to the median and the real world observations of nonconvergence. We modify Palfrey (1984) by introducing valence characteristics and show that there exist equilibria with entry in which the entrant may choose to be an extremist.Downsian model

Understanding the thermochemical conversion of biomass to overcome biomass recalcitrance

Thermochemical conversion technologies are promising pathways for producing environmentally benign, sustainable biofuels and value-added chemicals from biomass. However, reaction pathways and chemistry behind these technologies such as pyrolysis and solvolysis of biomass are very complex. Contributing to the complexity are the many factors that could affect the reaction mechanisms. This research focuses on an external effect on thermal decomposition and internal reaction chemistry to provide an insight into the biomass decomposition for better performance. First, the effect of low concentration of oxygen in sweep gas during biomass pyrolysis in fluidized bed was investigated for practical purpose. It was found that the partial oxidative pyrolysis can increase the yield of pyrolytic sugars. A continuation of the study was performed to produce sugar-rich bio-oil from the biomass passivation of alkali and alkaline earth metals. Partial oxidative pyrolysis of passivated biomass produced approximately 21 wt% hydrolyzable sugars in bio-oil. Additionally, partial oxidative pyrolysis also prevented clogging within the reactor by reducing char agglomerations ensuring continuous operation. Second, solvolytic conversion of lignin was studied using a micro reactor in the presence of a hydrogen donor solvent. The results showed that hydrogen donor solvents were effective in converting lignin into alkylphenols. It was found that a hydrogen donor solvent could suppress repolymerization reactions by stabilizing the primary products to alkyl-substituted phenols. Pyrolysis mechanisms of lignin were further studied using methoxy substituted α-O-4 dimeric model compounds. Pyrolysis of aryl-ether linkage primarily involved homolytic cleavage. It was discovered that methoxy group substitution on the aromatic ring increases the reactivity toward C - O homolysis. Additionally, free radicals in the condensed phase of the pyrolysis products were detected by electron paramagnetic resonance spectroscopy, providing information on the presence of oxygen-centered phenoxy and carbon-centered benzyl radicals. Furthermore, methoxy group substitution was revealed to promote oligomerization reactions to form large molecular weight compounds. Lastly, a quantitative investigation of free radicals in bio-oil and their potential role in condensed-phase polymerization was conducted. It was confirmed that both lignin and cellulose pyrolysis involve homolytic cleavage generating free radicals. Lignin bio-oil fractions contained a significant amount of radicals, which were found to be stable species due to highly delocalized in a pi system

Grain Quality Improvement in Japonica Rice : Achievements and Prospects

Several high grain quality rice varieties have been developed during the 2000\u27s. These varieties showed translucent, zero white-core, glossy and uniform milled-grain appearance, high palatability score of cooked rice and high percentage of whole grain after milling. The high eating quality variety group was lower in protein content, softer in gel consistency, and higher in breakdown and lower in consistency and setback viscosity measured by rapid visco-amylogram. In order to produce the low protein rice grain, the nitrogen fertilizer level has to be reduced to 90-110 kg per hectare with no nitrogen top dressing after heading. Rotational irrigation during rice growing season and delayed drainage after heading was found as effective in raising the whole grain yield and eating quality of cooked rice. Slow drying to 15-16% of grain moisture is recommended with air flow temperature below 50oC. Three hundred and ninety four native rice core collections were tested for their grain appearance, eating quality determining factors, and nutritional compounds. Health- enhancing potential and second metabolite contents were also evaluated. The native collections selected for high grain quality resources were used as cross parents and two new rice varieties having dark red pericarp color were developed from the crosses using Korean native varieties. The new variety had higher phenolic compounds in brown rice and the brown rice extract of this variety induced apoptotic cell deaths in H4II cells to a larger extent than the control rice extracts

Tetra(chlorido/iodido)(1,10-phenanthroline)platinum(IV) hemi[di(chlorine/iodine)]

The asymmetric unit of the title compound, [PtCl3.66I0.34(C12H8N2)]·0.5(Cl0.13I1.87), contains a neutral PtIV complex and one half of a halogen molecule. The PtIV ion is six-coordinated in a distorted octa­hedral environment by two N atoms of the 1,10-phenanthroline ligand and Cl or I atoms. The refinement of the structure and the EDX analysis indicate that the compound is a solid solution in which there is some substitution of Cl for I and vice versa. The chemical formula of the pure state of the compound would have been [PtCl4(C12H8N2)]·0.5I2. In the analysed crystal, two Cl atoms are partially (ca 25% and 9%) replaced by I atoms, and the I2 mol­ecule has a minor component modelled as ICl. As a result of the disorder, the different trans effects of the N and Cl/I atoms are not distinct. The complex displays inter­molecular π–π inter­actions between the six-membered rings, with a centroid–centroid distance of 3.771 (4) Å. There are also weak intra­molecular C—H⋯Cl hydrogen bonds

4,11-Diaza-1,8-diazo­niacyclo­tetra­decane bis­(pyridine-2-carboxyl­ate) dihydrate

The asymmetric unit of the title compound, C10H26N4 2+·2C6H4NO2 −·2H2O, consists of half of a doubly protonated 1,4,8,11-tetra­azacyclo­tetra­decane (cyclam) dication, a pyridine-2-carboxyl­ate anion and a solvent water mol­ecule. The complete dication is generated by a crystallographic centre and adopts an endodentate conformation which may be influenced by intra­molecular N—H⋯N hydrogen bonding. The carboxyl­ate group of the anion appears to be delocalized on the basis of the C—O bond lengths [1.257 (2) and 1.250 (2) Å]. In the crystal structure, the components are linked by inter­molecular N—H⋯O, N—H⋯N and O—H⋯O hydrogen bonds

6,12-Dihydro­dipyrido[1,2-a:1′,2′-d]pyrazinium bis­(perchlorate)

In the title compound, C12H12N2 2+·2ClO4 −, the dihedral angle between the two outer pyridine rings of the dication is 44.8 (1)°. In the crystal, weak intermolecular C—H⋯O hydrogen bonds occur