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1.
J Chem Phys ; 157(5): 054301, 2022 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-35933208

RESUMEN

Uranium nitride-oxide cations [NUO]+ and their complexes with equatorial N2 ligands, [NUO·(N2)n]+ (n = 1-7), were synthesized in the gas phase. Mass-selected infrared photodissociation spectroscopy and quantum chemical calculations confirm [NUO·(N2)5]+ to be a sterically fully coordinated cation, with electronic singlet ground state of 1A1, linear [NUO]+ core, and C5v structure. The presence of short N-U bond distances and high stretching modes, with slightly elongated U-O bond distances and lowered stretching modes, is rationalized by attributing them to cooperative covalent and dative [ǀN≡U≡Oǀ]+ triple bonds. The mutual trans-interaction through flexible electronic U-5f6d7sp valence shell and the linearly increasing perturbation with increase in the number of equatorial dative N2 ligands has also been explained, highlighting the bonding characteristics and distinct features of uranium chemistry.

2.
Chemistry ; 22(6): 2085-2091, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26748785

RESUMEN

The co-adsorption of O2 and CO on anionic sites of gold species is considered as a crucial step in the catalytic CO oxidation on gold catalysts. In this regard, the [Au2 O2 (CO)n ]- (n=2-6) complexes were prepared by using a laser vaporization supersonic ion source and were studied by using infrared photodissociation spectroscopy in the gas phase. All the [Au2 O2 (CO)n ]- (n=2-6) complexes were characterized to have a core structure involving one CO and one O2 molecule co-adsorbed on Au2- with the other CO molecules physically tagged around. The CO stretching frequency of the [Au2 O2 (CO)]- core ion is observed around ν˜ =2032-2042 cm-1 , which is about 200 cm-1 higher than that in [Au2 (CO)2 ]- . This frequency difference and the analyses based on density functional calculations provide direct evidence for the synergy effect of the chemically adsorbed O2 and CO. The low lying structures with carbonate group were not observed experimentally because of high formation barriers. The structures and the stability (i.e., the inertness in a sense) of the co-adsorbed O2 and CO on Au2- may have relevance to the elementary reaction steps on real gold catalysts.

3.
Zhongguo Zhen Jiu ; 42(3): 333-6, 2022 Mar 12.
Artículo en Zh | MEDLINE | ID: mdl-35272415

RESUMEN

To analyze the application feasibility of Tiaoshen Jianpi acupuncture and moxibustion in hospice care for terminal cancer patients. Tiaoshen Jianpi acupuncture and moxibustion adjusts the spirit to regulate emotions and fortifies the spleen to supplement and boost foundation of acquired (postnatal) constitution. And it could relieve adverse reactions after radiotherapy and chemotherapy, alleviate pain and regulate emotions in hospice care for terminal cancer patients, so as to promote the progress of hospice care for terminal cancer patients.


Asunto(s)
Terapia por Acupuntura , Cuidados Paliativos al Final de la Vida , Moxibustión , Neoplasias , Humanos , Neoplasias/terapia , Bazo
4.
J Phys Chem A ; 115(32): 9014-21, 2011 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-21721549

RESUMEN

The formation and structure of a novel species, a disuperoxo-cobalt dioxide complex (CoO(6)), has been investigated using matrix isolation in solid neon and argon, coupled to infrared spectroscopy and by quantum chemical methods. It is found that CoO(6) can be formed by successive complexation of cobalt dioxide by molecular oxygen without activation energy by diffusion of ground state O(2) molecules at 9K in the dark. The IR data on one combination and seven fundamentals, isotopic effects, and quantum chemical calculations are both consistent with an asymmetrical structure with two slightly nonequivalent oxygen ligands complexing a cobalt dioxide subunit. Evidence for other, metastable states is also presented, but the data are not complete. The electronic structure and formation pathway of this unique, formally +VI oxidation state, complex has been investigated using several functionals of current DFT within the broken-symmetry unrestricted formalism. It has been shown that the M06L pure local functional well reproduce the experimental observations. The ground electronic state is predicted to be an open shell (2)A'' doublet with the quartet states above by more than 9 kcal/mol and the sextet lying even higher in energy. The ground state has a strong and complex multireference character that hinders the use of more precise multireference approaches and requires caution in the methodology to be used. The geometrical, energetic, and vibrational properties have been computed.


Asunto(s)
Cobalto/química , Óxidos/química , Isótopos de Oxígeno/química , Oxígeno/química , Teoría Cuántica , Argón/química , Simulación por Computador , Estructura Molecular , Neón , Sales (Química)/química , Espectrofotometría Infrarroja/métodos , Vibración
5.
Ying Yong Sheng Tai Xue Bao ; 29(9): 2808-2818, 2018 Sep.
Artículo en Zh | MEDLINE | ID: mdl-30411555

RESUMEN

Thermal comfort is one of the ways assessing heat changes in climate change scenarios. Based on the daily observation data of 84 meteorological stations from Guizhou Province, the universal thermal climate index (UTCI) was used to examine the spatio-temporal variations and main influencing factors of thermal comfort at different elevations under the scenarios of climate change. Moreover, the impacts of different climatic factors on UTCI at different elevations were quantitatively analyzed. The results showed that the spatial distribution of annual UTCI in Guizhou Province had a strong consistency with that of annual temperature, which was decreasing with the increased elevation. The number of thermally comfortable days in most parts of the province was between 180 d and 240 d. UTCI increased with the increases of elevation, with the overall trends of UTCI [-0.58-1.38 ℃·(10 a)-1] being higher than the trends of temperature [-0.36-0.45 ℃·(10 a)-1] from 1984 to 2013. In general, the correlation coefficients between UTCI and climatic factors air tempe-rature, wind speed, atmosphere pressure, relative humidity and cloud cover were 0.899, -0.855, 0.818, -0.373, and -0.042, respectively. The correlations between climatic factors and UTCI varied across different elevations. The UTCI was affected lightly by air temperature and heavily by wind speed with increasing elevation.


Asunto(s)
Altitud , Cambio Climático , Sensación Térmica , Calor , Análisis Espacio-Temporal , Temperatura , Viento
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