Evidence for spin fluctuations in the deep-inelastic reaction 165Ho + 165Ho at 8.5 MeVamu

Both the magnitude and alignment of the transferred angular momentum in the reaction ¹⁶⁵Ho + ¹⁶⁵Ho have been measured as a function of Q-value via continuum γ-ray multiplicity and anisotropy techniques. The spin transfer and the continuum γ-ray anisotropy increase throughout the quasi-elastic region. The spin transfer as a function of Q-value saturates at ~ 35?/fragment, the anisotropy peaks at a value of ~2 and then decreases to near unity for the largest Q-values. The observed anisotropies are in good agreement with predictions from an equilibrium statistical model in which thermal excitation of angular-momentum-bearing collective modes and neutron evaporation give rise to in-plane components of the angular momentum.     

A modified analytical method for total antioxidant potential assay using RP-HPLC with electrochemical detection and its application for pro- and antioxidative properties of dopamine measurement

Total antioxidant potential (TAP) is usually measured using photometric or fluorometric assays. Preliminary results of a reversed-phase high-performance liquid chromatography--electrochemical detection assay are given. The method is based on the generation of hydroxyl radicals in a Fenton reaction and analysis of the product of their interaction with p-hydroxybenzoic acid (3,4-dihydroxybenzoic acid). The method is applied to estimate the TAP of dopamine. As a result, depending on the concentration, dopamine is pro- or antioxidant. The results are compared with TAP measurements using a standard photometric method.     

Base‐Free Iron Catalyzed Transfer Hydrogenation of Esters Using EtOH as Hydrogen Source

Herein, we report on the use of the iron pincer complex Iron‐MACHO‐BH, in the base‐free transfer hydrogenation of esters with EtOH as a hydrogen source. More than 20 substrates including aromatic and aliphatic esters and lactones were reduced affording the desired primary alcohols and diols with moderate to excellent isolated yields. It is also possible to reduce polyesters to the diols with this method, enabling a novel way of plastic recycling. Reduction of the renewable substrate methyl levulinate proceeds to form 1,4‐pentanediol directly. The yields are largely governed by the equilibrium between the alcohol and the ethyl ester.     

Mass spectrometry analysis of in vitro nitration of a recombinant human IgG1 monoclonal antibody

Nitration of a recombinant human monoclonal antibody was carried out in vitro by incubating the antibody with the nitrating reagent tetranitromethane (TNM). The susceptible sites of nitration were identified using high-performance liquid chromatography/mass spectrometry (HPLC/MS). In general, tyrosine residues in the variable domains of the antibody are more susceptible to nitration, while tyrosine residues in the constant domains are relatively resistant to nitration. However, one tyrosine residue in the CH1 domain and one tyrosine residue in the CH2 domain are highly susceptible to nitration. Interestingly, the susceptible tyrosine residue in the CH2 domain is followed by the conserved asparagine residue that is glycosylated.     

Experimental Investigation of thermal convection in an inclined narrow gap II

In the past decade the development in micro technology has experienced great progress, what made the knowledge of the flow behavior in small cavities fundamentally interesting. Our experimental contribution describes the measured temperature and velocity fields in a fluid containing inclined cavity with the dimensions 17 × 6 × 24 mm³ (w × d × h). Using PIV/T, we can determine the velocity and temperature distribution in the cavity simultaneously. The chamber is illuminated with a white light sheet of 1 mm. A 20% glycerin-water mixture is examined. The lower side is heated to 46.2°C, while the upper side has a constant temperature of 26°C. In this work we present the measured velocity and temperature fields of the fluid at different angles of the cavity orientation with respect to the direction of gravity in the stationary state. This is a continuation of last years presentation [1] in the sense that the temperature difference has been substantially increased. (© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Stereodefined dinucleoside (3′,5′)-propionamidophosphonates and β-cyanoethylphosphonates and their incorporation into modified oligonucleotides

Base-catalyzed stereospecific anti-Markovnikov addition of dinucleoside (3′,5′)-H-phosphonates to the activated alkenes acrylamide and acrylonitrile resulting in the synthesis of P-chiral diastereomerically pure dinucleoside (3′,5′)-alkylphosphonates is reported.     

Sequential fission angular distributions from mass-asymmetric heavy-ion reactions

The angular distributions of sequential fission fragments have been measured for the reactions of ⁴⁰Ar with ¹⁹⁷Au and ²³⁸U as a function of reaction Q-value and charge transfer. These angular, distributions are used to study the angular momentum and alignment of the deep-inelastic products which undergo fission. All of the fission fragment angular distributions are strongly focused into the plane defined by the beam and the projectile-like fragment velocity vectors. The in-plane angular distributions from reactions with uranium are isotropic for small energy losses and become anisotropic as the energy loss increases. For large negative Q-values, the in-plane anisotropy increases as the deep-inelastic products become more symmetric. The variation of the in-plane anisotropy with mass asymmetry for the two systems in this work was compared to a compilation of previous work and a consistent pattern was found. These alignment data are compared to equilibrium statistical calculations.     

Mercury trifluoroacetate-catalyzed conversion of Se-alkyl phosphoroselenolates into the corresponding phosphates

The role of mercuric trifluoroacetate as reactive agent and activator in reactions of various Se-alkyl phosphoroselenoates with O- and N-nucleophiles is examined. The formation of mercury-complexed intermediates of putative mixed anhydride-like structure is indicated.