Thermal and chemical evolution of primordial gas clouds irradiated with farultraviolet (FUV; hν < 13.6 eV) radiation is investigated. In clouds irradiated by intense FUV radiation, sufficient hydrogen molecules to be important for cooling are never formed. However, even without molecular hydrogen, if the clouds are massive enough, they start collapsing via atomic hydrogen line cooling. Such clo...

The formation of water through hydrogenation of oxygen on platinum occurs at a surprisingly low reaction rate. The reaction rate limited process for this catalytic reaction is, however, yet to be settled. In the present work, the reaction rates of the first and the second hydrogen addition steps are compared when hydrogen is obtained through intense synchrotron radiation that induces proton pro...

The kinetics of propionate degradation, acetate splitting, and hydrogen consumption in digesting sludge were investigated in a lab-scale digester. At natural steady-state conditions, the acetate-splitting systems in well-digested sludge were about half saturated. Propionate-degrading systems were saturated to only 10 to 15%, and hydrogen removal was less than 1% of the maximum possible rate. It...

Isotopic effects on the formation and dissociation kinetics of hydrogen bonds are studied in real time with ultrafast chemical exchange spectroscopy. The dissociation time of hydrogen bond between phenol-OH and p-xylene (or mesitylene) is found to be identical to that between phenol-OD and p-xylene (or mesitylene) in the same solvents. The experimental results demonstrate that the isotope subst...

The next generation of experiments for making cold anti-hydrogen will attempt to trap them using multipole magnetic fields. We investigate the motion of the anti-protons through the combined electric and magnetic fields of this type of trap. The multipole fields that will prevent the anti-hydrogen from hitting the walls cause the anti-protons to have regions of regular motion and regions of cha...

hydrogenation of oils might be considered as the largest reaction in the edible oil industry. the reaction consists of the addition of hydrogen at the double bounds of fatty acids. although for some reasons this might be considered a desirable reaction but for some others it might create problems in the food and nutrition chain circle due to the formation of saturated and trans fatty acids. soy...

Symmetric oligothiophene derivatives containing hydrogen bond forming segments create self-supporting organogels consisting of self-assembled 1D nanostructures at low concentrations. Hydrogen bond formation and π-π stacking were both found to be crucial for the formation of conductive supramolecular networks of 1D nanostructures.

in this paper, a novel method of producing bi-metallic alloy nanoparticles at low temperatures using hydrogen bombardment of thin films, deposited on glass substrates, is introduced. optical and morphological characteristics of the nanoparticles were extensively studied for various conditions of plasma treatment, such as plasma power density, temperature, duration of hydrogen bombardment, thick...

High quality ab initio computations and molecular spectroscopy of small hydrogen-bonded clusters in the vapor phase provide highly accurate data in general agreement with the theory of hydrogen bonds developed in the seventies. Hydrogen bonding is a major force determining energetics and structures of biopolymers. In addition to direct influence through the directionality hydrogen bonds set the...

effects of temperature and percentage of organic modifier were studied on retention and selectivity in rp-hplc using solvation parameter model. the system constants were determined by multiple linear regression analysis from experimental values in the retention factor for a group of different solutes with known descriptors by computer using the program spss/pc. the experimental results showed t...