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1.
Nucleus (La Habana) ; (63): 9-11, Jan.-June 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-990200

RESUMEN

Abstract Heavy quark c c ¯ has been studied in the non relativistic framework using a quark-quark potential as a sum of power of the corresponding distance. The form of potential is based on phenomenological facts. The problem was solved numerically using a program written on C++. Mass spectra and the expectation value of the radius have been estimated for different quantum-mechanical states for c c ¯ system. The results have been compared with other similar and recent works. The mass spectra obtained is in acceptable agreement with the experimental data for c c ¯.


Resumen El sistema de quarks pesados c c ¯ ha sido estudiado en el marco no relativista usando un potencial quark-quark de la forma de la suma de potencias de la distancia entre las partículas. El problema se resolvió numéricamente usando un programa escrito en C++. Se estimaron el espectro de masa y el valor esperado del radio para diferentes estados de excitación. Los resultados fueron comparados con otros trabajos similares recientes. El espectro de masa obtenido concuerda de manera aceptable con los datos experimentales para el sistema c c ¯.

2.
Artículo en Inglés | IMSEAR | ID: sea-151588

RESUMEN

Quinazoline derivatives have been very well known for Antihypertensive activity. Seven new Quinazoline derivatives are synthesized by three steps. Purity of compound is checked by TLC monitoring. All synthesized compounds are confirmed by UV, IR, Mass and H1NMR. All synthesized compound were screened for α1-adrenergic receptor blocking activity. Amongst all synthesized compounds 4a & 4e showed better activity.

3.
Artículo en Chino | WPRIM | ID: wpr-680046

RESUMEN

Objective: To analyze the chemical constituents of the essential oil extracted from the seeds of Myristica fragrans Houtt.(nutmeg) in Indonesia and to provide qualities control scientific foundations.Methods: The essential oil was extracted by steam distillation and separated with GC capillary column.The relative content of every compound was determined by normalization method and the chemical compositions were evaluated by GC-MS.Results: Ninety-three chromatographic peaks were isolated and sixty-one compounds were identified,accounting for 97.62% of the total essential oil in nutmeg.Conclusion: The essential components of nutmeg in Indonesia is monoterpenoids and it's derivatives,accounting for 78.87% of the total essential oil.And phenolic compounds were the secondary composition,accounting for 16.79%.The essential oil contains safrole,which can induce genetoxicity and mutagenicity in animal,and myristicin and elemicin which can induce illusion.So,it must be careful when Myristica fragrans Houtt was used.

4.
Artículo en Chino | WPRIM | ID: wpr-548361

RESUMEN

Objective To develop a method for the determination to organochlorine pesticides by gas chromatography-mass spectra-mass spectra.Methods The temperature of inlet was 250 ℃,the injection volume was 1 ?l,without split injection.The temperature of EI source was 300 ℃,the ionization energy was 70 eV,solvent delay time was 3.75 min,transfer line temperature was 280 ℃.181,235,246(m/z)were selected as parent ion,and 145,165,176(m/z)were sub ion.Results In the range of 0-50 ?g/L,every component had a good linearity,r≥0.99,the limit of detection≤0.01 ?g/L.Its average rate of recovery was in the range of 86.1%-101.8%,and the relative standard deviations(RSDs) were between 4.41%-8.07%.Conclusion Gas chromatography-mass spectra-mass spectra is more precise for the qualitative and quantitative determination of trace organochlorine pesticides residues in drinking water.

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