RESUMO
In Europe, REACH legislation encourages the use of alternative in silico methods such as (Q)SAR models. According to the recent progress of Chemical Substances Control Law (CSCL) in Japan, (Q)SAR predictions are also utilized as supporting evidence for the assessment of bioaccumulation potential of chemicals along with read across. Currently, the effective use of read across and QSARs is examined for other hazards, including biodegradability. This paper describes the results of external validation and improvement of CATALOGIC 301C model based on more than 1000 tested new chemical substances of the publication schedule under CSCL. CATALOGIC 301C model meets all REACH requirements to be used for biodegradability assessment. The model formalism built on scientific understanding for the microbial degradation of chemicals has a well-defined and transparent applicability domain. The model predictions are adequate for the evaluation of the ready degradability of chemicals.
Assuntos
Biodegradação Ambiental , Poluentes Ambientais/química , Substâncias Perigosas/química , Modelos Biológicos , Análise da Demanda Biológica de Oxigênio , Bases de Dados de Compostos Químicos , Poluentes Ambientais/metabolismo , Substâncias Perigosas/metabolismo , Japão , Relação Quantitativa Estrutura-Atividade , Reprodutibilidade dos TestesRESUMO
We report periodic pulse oscillation in an intracavity-doubled Nd:YVO(4) laser. The pulse oscillation is caused by alternate oscillation between two modes. We investigated improvement of green-light power with the pulse oscillation in a Nd:YVO(4) laser. The pulse oscillation gave a factor of approximately 2 higher average green-light power than that for cw oscillation at the same pumping power.
RESUMO
Diosgenin[(25R)-spirost-5-en-3 beta-ol] and cholesterol were detected as trimethylsilyl derivatives by gas chromatography-mass spectrometry in an alkaline lysate of a new hypotensive phospholipid from the lipid fraction of bovine brain. These steroids seemed to be present in the hypotensive phospholipid fraction in some bound forms.
Assuntos
Química Encefálica , Diosgenina/análise , Proteínas do Tecido Nervoso/análise , Fosfolipídeos/análise , Sapogeninas/análise , Animais , Bovinos , Colesterol/análise , Cromatografia Gasosa-Espectrometria de MassasRESUMO
We use a magnetic field applied along the axis of a semiconductor superlattice (SL) as a controllable means of creating a one-dimensional band structure. We demonstrate that the current flow through the SL is strongly suppressed when the electron motion perpendicular to the SL axis is strongly confined by the quantizing magnetic field. By modeling this behavior using semiclassical and nonequilibrium Green's function methods, we show that the observed quenching arises from a qualitative change in electron dynamics caused by increasing quantum confinement.