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1.
Inorg Chem ; 56(19): 11513-11523, 2017 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-28901753

RESUMO

Metal-rich, mixed copper-rhodium sulfide Cu3-δRh34S30 that represents a new Cu-filled variant of the Rh17S15 structure has been synthesized and structurally characterized. Copper content in the [CuRh8] cubic cluster was found to vary notably dependent on the chosen synthetic route. Full site occupancy was achieved only in nanoscaled Cu3Rh34S30 obtained by a rapid, microwave-assisted reaction of CuCl, Rh2(CH3CO2)4 and thiosemicarbazide at 300 °C in just 30 min; whereas merely Cu-deficient Cu3-δRh34S30 (2.0 ≥ δ ≥ 0.9) compositions were realized via conventional high-temperature ceramic synthesis from the elements at 950 °C. Although Cu3-δRh34S30 is metallic just like Rh17S15, the slightly enhanced metal content has a dramatic effect on the electronic properties. Whereas the Rh17S15 host undergoes a superconducting transition at 5.4 K, no signs of the latter were found for the Cu-derivatives at least down to 1.8 K. This finding is corroborated by the strongly reduced density of states at the Fermi level of the ternary sulfide and the disruption of long-range Rh-Rh interactions in favor of Cu-Rh interactions as revealed by quantum-chemical calculations.

2.
Soc Psychiatry Psychiatr Epidemiol ; 52(8): 989-1003, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28285452

RESUMO

PURPOSE: There is disregard in the scientific literature for the evaluation of psychiatric in-patient care as rated directly by patients. In this context, we aimed to explore satisfaction of people treated in mental health in-patient facilities. The project was a part of the Young Psychiatrist Program by the Association for the Improvement of Mental Health Programmes. METHODS: This is an international multicentre cross-sectional study conducted in 25 hospitals across 11 countries. The research team at each study site approached a consecutive target sample of 30 discharged patients to measure their satisfaction using the five-item study-specific questionnaire. Individual and institution level correlates of 'low satisfaction' were examined by comparisons of binary and multivariate associations in multilevel regression models. RESULTS: A final study sample consisted of 673 participants. Total satisfaction scores were highly skewed towards the upper end of the scale, with a median total score of 44 (interquartile range 38-48) out of 50. After taking clustering into account, the only independent correlates of low satisfaction were schizophrenia diagnosis and low psychiatrist to patient ratio. CONCLUSION: Further studies on patients' satisfaction should additionally pay attention to treatment expectations formed by the previous experience of treatment, service-related knowledge, stigma and patients' disempowerment, and power imbalance.


Assuntos
Hospitais Psiquiátricos , Transtornos Mentais/terapia , Satisfação do Paciente/estatística & dados numéricos , Adulto , Estudos Transversais , Feminino , Humanos , Internacionalidade , Masculino , Pessoa de Meia-Idade , Análise Multinível , Alta do Paciente , Inquéritos e Questionários
3.
Inorg Chem ; 55(9): 4498-503, 2016 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-27064595

RESUMO

We report the high-pressure high-temperature synthesis (P = 15 GPa, T = 1300 K) of BaGe3(tI32) adopting a CaGe3-type crystal structure. Bonding analysis reveals layers of covalently bonded germanium dumbbells being involved in multicenter Ba-Ge interactions. Physical measurements evidence metal-type electrical conductivity and a transition to a superconducting state at 6.5 K. Chemical bonding and physical properties of the new modification are discussed in comparison to the earlier described hexagonal form BaGe3(hP8) with a columnar arrangement of Ge3 triangles.

4.
J Chem Phys ; 145(15): 154107, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27782480

RESUMO

Plane waves are one of the most popular and efficient basis sets for electronic structure calculations of solids; however, their delocalized nature makes it difficult to employ for them classical orbital-based methods of chemical bonding analysis. The quantum chemical topology approach, introducing chemical concepts via partitioning of real space into chemically meaningful domains, has no difficulties with plane-wave-based basis sets. Many popular tools employed within this approach, for instance delocalization indices, need overlap integrals over these domains-the elements of the so called domain overlap matrices. This article reports an efficient algorithm for evaluation of domain overlap matrix elements for plane-wave-based calculations as well as evaluation of its implementation for one of the most popular projector augmented wave (PAW) methods on the small set of simple and complex solids. The stability of the obtained results with respect to PAW calculation parameters has been investigated, and the comparison of the results with the results from other calculation methods has also been made.

5.
J Comput Chem ; 35(7): 565-85, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24436089

RESUMO

For the fully relativistic 4-component many-electron wavefunction six flavors of electron localizability indicators (ELI) have been proposed. Their counterparts, suitable for the application to the 2-component wavefunctions, have been also derived. Six proposed indicators have been tested on Ar and Rn atoms and one of them, the ELI-D for spatially antisymmetrized electron pairs, has been found to reveal atomic shell structures at quantitative level. Shell structures of all the atoms of periods 4-7 of the periodic table have been obtained using this indicator and compared with these obtained from the nonrelativistic limit calculations as well as from scalar-relativistic (zero-order regular approximation) calculations.

6.
Angew Chem Int Ed Engl ; 53(28): 7344-8, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-24866268

RESUMO

Nanoparticles of Bi3 Ir, obtained from a microwave-assisted polyol process, activate molecular oxygen from air at room temperature and reversibly intercalate it as oxide ions. The closely related structures of Bi3 Ir and Bi3 IrOx (x≤2) were investigated by X-ray diffraction, electron microscopy, and quantum-chemical modeling. In the topochemically formed metallic suboxide, the intermetallic building units are fully preserved. Time- and temperature-dependent monitoring of the oxygen uptake in an oxygen-filled chamber shows that the activation energy for oxide diffusion (84 meV) is one order of magnitude smaller than that in any known material. Bi3 IrOx is the first metallic oxide ion conductor and also the first that operates at room temperature.

7.
J Am Chem Soc ; 134(33): 13558-61, 2012 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-22845167

RESUMO

The new metastable binary silicides MSi(3) (M = Ca, Y, Lu) have been synthesized by high-pressure, high-temperature reactions at pressures between 12(2) and 15(2) GPa and temperatures from 900(100) to 1400(150) K. The atomic patterns comprise intricate silicon layers of condensed molecule-like Si(2) dimers. The alkaline-earth element adopts the oxidation state +2, while the rare-earth and transition metals realize +3. All of the compounds exhibit BCS-type superconductivity with weak electron-phonon coupling below critical temperatures of up to 7 K.

8.
J Chem Phys ; 137(21): 214109, 2012 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-23231219

RESUMO

The domain-averaged Fermi hole (DAFH) orbitals provide highly visual representation of bonding in terms of orbital-like functions with attributed occupation numbers. It was successfully applied on many molecular systems including those with non-trivial bonding patterns. This article reports for the first time the extension of the DAFH analysis to the realm of extended periodic systems. Simple analytical model of DAFH orbital for single-band solids is introduced which allows to rationalize typical features that DAFH orbitals for extended systems may possess. In particular, a connection between Wannier and DAFH orbitals has been analyzed. The analysis of DAFH orbitals on the basis of DFT calculations is applied to hydrogen lattices of different dimensions as well as to the solids diamond, graphite, Na, Cu and NaCl. In case of hydrogen lattices, remarkable similarity is found between the DAFH orbitals evaluated with both the analytical approach and DFT. In case of the selected ionic and covalent solids the DAFH orbitals deliver bonding descriptions, which are compatible with classical orbital interpretation. For metals the DAFH analysis shows essential multicenter nature of bonding.


Assuntos
Modelos Moleculares , Cobre/química , Diamante/química , Grafite/química , Hidrogênio/química , Conformação Molecular , Teoria Quântica , Sódio/química , Cloreto de Sódio/química
9.
J Comput Chem ; 32(10): 2064-76, 2011 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-21538404

RESUMO

The electron localization and delocalization indices obtained by the integration of exchange-correlation part of pair density over chemically meaningful regions of space, e.g., QTAIM atoms are valuable tools for the bonding analysis in molecular systems. However, among periodic systems only few simplest models were analyzed with this approach until now. This contribution reports implementation and evaluation of the localization and delocalization indices on the basis of solid state DFT calculations. A comparison with the results of simple analytical model of Ponec was made. In addition, a small set of compounds with ionic (NaCl), covalent (diamond, graphite), and metallic (Na, Cu) bonding interactions was characterized using this method. Typical features of different types of bonding were discussed using the delocalization indices.

10.
Chemistry ; 17(23): 6382-8, 2011 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-21520305

RESUMO

Shiny black, air-insensitive crystals of tellurium-rich one-dimensional coordination polymers were synthesized by melting a mixture of the elements with TeCl(4). The compounds [Ru(Te(9))](InCl(4))(2) and [Ru(Te(8))]Cl(2) crystallize in the monoclinic space group type C2/c, whereas [Rh(Te(6))]Cl(3) adopts the trigonal space group type R ̅3c. In the crystal structures, linear, positively charged [M(m+) (Te(n)(±0))] (M=Ru, m=2; Rh, m=3) chains run parallel to the c axes. Each of the uncharged Te(n) molecules (n=6, 8, 9) coordinates two transition-metal atoms as a bridging bis-tridentate ligand. Because the coordinating tellurium atoms act as electron-pair donors, the 18-electron rule is fulfilled for the octahedrally coordinated transition-metal cations. Based on DFT calculations, the quantum theory of atoms in molecules (QTAIM) and the electron localizability indicator (ELI) provide insight into the principles of the polar donor bonding in these complexes. Comparison with optimized ring geometries reveals substantial tension in the coordinating tellurium molecules.

11.
Eur J Transl Myol ; 31(4)2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34911289

RESUMO

Arterial hypertension (AH) is a burning problem in the world. Antihypertensive pharmacological therapy combined by physical exercises is well-studied in patients with mild and moderate AH. However, studies that have investigated relaxation in patients with severe AH in addition to drug therapy are lacking. Optimization of a comprehensive treatment for patients with severe AH, by using a multicomponent rational antihypertensive pharmacotherapy (PT) with subsequent application of relaxation exercise therapy (RET). The study involved 32 male patients with severe AH. Initially, clinical-instrumental and laboratory examination, blood pressure registration and daily arterial blood pressure monitoring were carried out. Suitable PT was selected for all the patients. 3 months after starting PT the patients were divided in 2 groups. The patients of the 1st group were prescribed RET in addition to PT. The 2nd group of patients continued receiving PT alone. 3 months later, average daily blood pressure (ADBP)-syst and ADBP-diast were compared in both groups. Three months after PT both groups demonstrated a significant decrease in ADBP-syst and ADBP diast, but these indicators remained higher than normal and did not reach the target level. Three months after the inclusion of RET in the comprehensive treatment, the 1st group demonstrated a significant decrease in ADBP (systolic and diastolic), not only in comparison with the initial data, but also with the data observed three months after PT. After 6 months, ADBP-syst and ADBP-diast in the 1st group were significantly lower compared with those of patients in the 2nd group. The inclusion of RET in addition to a multicomponent antihypertensive PT is a promising treatment option for severe AH.

13.
Acta Crystallogr B Struct Sci Cryst Eng Mater ; 71(Pt 6): 777-87, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26634735

RESUMO

Binary vanadium borides are suitable model systems for a systematic analysis of the transferability concept in intermetallic compounds due to chemical intergrowth in their crystal structures. In order to underline this structural relationship, topological properties of the electron density in VB, V3B4 and VB2 reconstructed from high-resolution single-crystal X-ray diffraction data as well as derived from quantum chemical calculations, are analysed in terms of Bader's Quantum Theory of Atoms in Molecules [Bader (1990). Atoms in Molecules: A Quantum Theory, 1st ed. Oxford: Clarendon Press]. The compounds VB, V3B4 and VB2 are characterized by a charge transfer from the metal to boron together with two predominant atomic interactions, the shared covalent B-B interactions and the polar covalent B-M interactions. The resembling features of the crystal structures are well reflected by the respective B-B interatomic distances as well as by ρ(r) values at the B-B bond critical points. The latter decrease with an increase in the corresponding interatomic distances. The B-B bonds show transferable electron density properties at bond critical points depending on the respective bond distances.

14.
Inorg Chem ; 44(26): 9622-4, 2005 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-16363825

RESUMO

The first compounds, Hg(7)Ag(2)P(8)X(6) (X = Br, I) and Hg(6)Ag(4)P(8)Br(6), featuring the partial isoelectronic substitution of Hg(2+) for Ag(1+) in mercury-pnicogen frameworks have been obtained and structurally characterized. The new compounds are the supramolecular assemblies built of the covalently bonded metal-pnicogen frameworks trapping guests of different complexity. The frameworks feature the perfect ordering of Hg(2+) and Ag(1+) cations and contain P(2)(4)(-) and P(6)(6)(-) phosphorus clusters. The substitution of Hg(2+) with Ag(1+) leads to the reduction in charge of the host cluster-containing cationic matrix and concomitant replacement of the monatomic X(-) guest by a lesser amount of the AgBr(3)(2)(-) anions.

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