Visible-light-driven 1,2-hydro(cyanomethylation) of alkenes with chloroacetonitrile.

A regioselective 1,2-hydro(cyanomethylation) of unactivated aliphatic alkenes is reported. A cyanomethyl radical is generated from haloacetonitriles. This radical adds onto alkenes to form alkyl radicals, which undergo hydrogen atom transfer from thiol to produce one-carbon-extended nitriles.

Acoustodynamic Covalent Materials Engineering for the Remote Control of Physical Properties Inside Materials.

Advances in vat photopolymerization (VP) 3D printing (3DP) technology enable the production of highly precise 3D objects. However, it is a major challenge to create dynamic functionalities and to manipulate the physical properties of the inherently insoluble and infusible cross-linked material generated from VP-3DP without reproduction. The fabrication of light- and high-intensity focused ultrasound (HIFU)-responsive cross-linked polymeric materials linked with hexaarylbiimidazole (HABI) in polymer chains based on VP-3DP is reported here.

Characterization of four arginine kinases in the ciliate Paramecium tetraurelia: Investigation on the substrate inhibition mechanism.

The ciliate Paramecium tetraurelia contains four arginine kinase genes (AK1-4). We detected cDNA for only three of the AKs (AK1-3) via PCR. Recombinant AK1-4 were expressed in Escherichia coli and their kinetics parameters determined.

Design and development of a novel nuclear magnetic resonance detection for the gas phase ions by magnetic resonance acceleration technique.

Nuclear magnetic resonance (NMR) technique is a well-established powerful tool to study the physical and chemical properties of a wide range of materials. However, presently, NMR applications are essentially limited to materials in the condensed phase. Although magnetic resonance was originally demonstrated in gas phase molecular beam experiments, no application to gas phase molecular ions has yet been demonstrated.

Solvation structure and stability of [(CH3)2NH]m(NH3)n-H hypervalent clusters: ionization potentials and switching of hydrogen-atom localized site.

Ionization potentials (IPs) of [(CH(3))(2)NH](m)(NH(3))(n)-H hypervalent radical clusters produced by an ArF excimer laser photolysis of dimethylamine (DMA)-ammonia mixed clusters are determined by the photoionization threshold measurements. The IPs of the DMA(1)(NH(3))(n)-H hypervalent radicals decrease rapidly with the number of ammonia up to n=4, and then its decrease rate becomes much slower for n ≥ 5. This trend is very similar to that found for NH(4)(NH(3))(n) clusters.

Infrared spectroscopy of jet-cooled tautomeric dimer of 7-azaindole: a model system for the ground-state double proton transfer reaction.

To investigate the ground-state double proton transfer (GSDPT) reaction, we carried out a laser spectroscopic study on the tautomeric dimer of 7-azaindole in a supersonic jet. We have recorded an infrared (IR) spectrum of the tautomeric dimer in the S(0) state. The NH band exhibits a broad and less-structured pattern.

Microsolvation and protonation effects on geometric and electronic structures of tryptophan and tryptophan-containing dipeptides.

Photodissociation spectroscopy of solvated clusters of protonated tryptophan (TrpH(+)) and dipeptides containing tryptophan (Val-TrpH(+), Ala-TrpH(+), and Gly-TrpH(+)) has been carried out at low temperature to investigate the protonation and solvation effects on the electronic spectrum. For the protonated dipeptides, the S(1)-S(0) transition exhibits a substantial red shift due to the stronger interaction between the NH(3)(+) group and the indole pi ring. The S(1)-S(0) spectra of TrpH(+)(CH(3)OH)(n) clusters exhibit a drastic change with the number of methanol molecules.

Photodissociation and spectroscopic study of cold protonated dipeptides.

A photodissociation spectrometer, containing a spray ionization source and a temperature-variable multipole ion trap, has been constructed to examine the structure and reactivity of gas phase biological molecular ions at various temperatures. Ultraviolet (UV) and infrared (IR) photodissociation spectra of protonated alanyltryptophan (Ala-TrpH+) and tryptophanylglycine (Trp-GlyH+) have been measured. In UV spectra, the S1-S0 band origin of Ala-TrpH+ exhibits a significant red shift with respect to those of protonated tryptophan (TrpH+) and Trp-GlyH+.

Hydration process of Na2- in small water clusters: photoelectron spectroscopy and theoretical study of Na2- (H2O)n.

Photoelectron spectroscopy (PES) of Na2- (H2O)n (n < or = 6) was investigated to examine the solvation of sodium aggregates in small water clusters. The PES bands for the transitions from the anion to the neutral ground and first excited states derived from Na2 (1(1)Sigmag+) and Na2 (1(3)Sigmau+) shifted gradually to the blue, and those to the higher-excited states correlated to the 3(2)S + 3(2)P asymptote dropped down rapidly to the red and almost degenerated on the 1(3)Sigmau+-type band at n = 4. Quantum chemical calculations for n up to 3 showed that the spectra can be ascribed to structures where one of the Na atoms is selectively hydrated.

Development of ELISA using recombinant antigens for specific detection of mouse parvovirus infection.

Nucleotide sequences of mouse parvovirus (MPV) isolate, named MPV/UT, and mouse minute virus (MMV) were analyzed and used for expressing recombinant proteins in E. coli. ELISA tests using recombinant major capsid protein (rVP2) and recombinant major non-structural protein (rNS1) as antigens were developed and their performance in serologic detection of rodent parvovirus infection was assessed.

Multiphoton ionization and oxidation processes of Mg-ammonia clusters.

Multiphoton ionization and oxidation processes of ammoniated magnesium clusters are investigated by the multiphoton ionization method with an intense femtosecond laser. In the photoionization of mass-selected Mg+ (NH3)n, evaporation dominates at lower laser intensity, while the oxidation reaction to produce H-atom elimination products, MgNH2+ (NH3)m, becomes predominant at higher intensity. In addition to these fragment ions, doubly-charged ions are observed for n > or = 2 at the laser intensity higher than 10(12) W cm(-2).

Apatite-forming ability and mechanical properties of PTMO-modified CaO-SiO2-TiO2 hybrids derived from sol-gel processing.

Hydrolysis and polycondensation of triethoxysilane end-capped Poly (tetramethylene oxide) (Si-PTMO), tetraethoxysilane (TEOS), tetraisopropyltitanate (TiPT) and calcium nitrate (Ca(NO(3))(2)) gave transparent monolithics of PTMO-modified CaO-SiO(2)-TiO(2) hybrids. The samples with (TiPT)/(TEOS+TiPT) molar ratios from 0 to 0.20 under constant ratio of (Si-PTMO)/(TEOS+TiPT) of 2/3 in weight were prepared.

Apatite-forming ability and mechanical properties of PTMO-modified CaO-SiO2 hybrids prepared by sol-gel processing: effect of CaO and PTMO contents.

Transparent monolithics of triethoxysilane end-capped poly(tetramethylene oxide) (Si-PTMO)-modified CaO-SiO2 hybrids were successfully synthesized by hydrolysis and polycondensation of Si-PTMO, tetraethoxysilane (TEOS) and calcium nitrate. As for the samples with varying (Ca(NO3)2)/(TEOS) molar ratios under constant ratio of (Si-PTMO)/(TEOS) of 2/3 in weight. the apatite-forming ability in a simulated body fluid (SBF) which is indicative of bioactivity.