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1.
J Chem Phys ; 126(16): 164710, 2007 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-17477627

RESUMO

Integral and angle resolved thermal desorption spectroscopies were used to study methanol adsorption and oxidation on clean and oxygen covered Cu(110) surfaces. Special emphasis was put on the Cu-CuO stripe phase, which forms when the Cu(110) surface is covered with 0.25 ML of oxygen. In the temperature regime between 200 and 300 K associative desorption of methanol and water takes place, showing a normal desorption character with peaks shifting to lower temperature with increasing coverage and with a nearly cosine angular desorption distribution. In the temperature range of about 350 K formaldehyde, hydrogen, and again methanol desorb nearly concomitantly in the form of a very narrow peak (full width at half maximum=10 K), with peaks shifting to higher temperature with increasing methanol coverage. The angular distribution of these peaks is strongly forward focused, indicating activation barriers being involved. In the case of the Cu-CuO stripe phase the angular distribution of the desorption products is clearly different in the [110] and [001] azimuthal directions, demonstrating the influence of the border lines between the copper and the copper oxide stripes on the desorption process.

2.
Phys Rev Lett ; 96(24): 246101, 2006 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-16907255

RESUMO

Direct in situ x-ray surface scattering studies of growth at a solid-liquid interface are demonstrated using the homoepitaxial electrodeposition on Au(100) as an example. With decreasing potential transitions from step-flow to layer-by-layer growth, manifested by layering oscillations in the x-ray intensity, then to multilayer growth, and finally back to layer-by-layer growth were observed. This complex growth behavior can be explained by the effect of anion coadsorbates and the potential-dependent Au surface reconstruction on the Au surface mobility.

3.
Phys Rev Lett ; 95(25): 256104, 2005 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-16384477

RESUMO

We have determined the dispersion of acoustic and optical surface phonon modes 2H-NbSe2 at the by inelastic x-ray scattering under grazing incidence conditions. Already, at room temperature, an anomaly is observed close to the charge density wave -vector position located at about one-third along the Gamma-M direction of the Brillouin zone. Our results indicate that the anomaly for the surface mode occurs at a lower energy than that measured in bulk sensitive geometry in the same experiment, showing evidence of a modified behavior in the uppermost layers. We demonstrate that inelastic x-ray scattering in grazing incidence conditions provides a unique tool to selectively study either surface or bulk lattice dynamics in a single experiment.

4.
Phys Rev Lett ; 94(6): 066106, 2005 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-15783756

RESUMO

In situ grazing-incidence x-ray diffraction studies of reconstructed Au(111) electrodes in aqueous electrolyte solutions are presented, which reveal a significantly increased compression of the Au surface layer during Au electrodeposition as compared to Au(111) surfaces under ultrahigh vacuum conditions or in the Au-free electrolyte. The compression increases towards more negative potentials, reaching 5.3% at the most negative potentials studied. It may be explained within a simple thermodynamic model by a release of potential-induced surface stress.

5.
Phys Rev E Stat Nonlin Soft Matter Phys ; 64(6 Pt 1): 061508, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11736192

RESUMO

The surfaces of polystyrene (PS) films decorated with gold nanoclusters were investigated by x-ray reflectivity measurements. The thicknesses of the films are much larger than the radii of gyration of the different PS samples. By annealing the films above the glass transition temperature T(g) an embedding process of the clusters into the polymer is detected which is accompanied by a substantial increase in the cluster layer thickness due to Brownian motion. These processes start at a sufficiently low viscosity and may be regarded as a probe of the glass transition in the near surface region of the PS films. Simultaneously the thermal expansion of the entire film and hence its approximate bulk behavior were monitored. Two samples of different molecular weight do not show a significant difference between the surface and bulk T(g) values.

6.
Ginekol Pol ; 71(5): 419-26, 2000 May.
Artigo em Polonês | MEDLINE | ID: mdl-10943042

RESUMO

The aim of the study is to define the systemic prognostic factors in the neoplasm according to thermodynamic theory of cancer a the self-organising dissipative structure. As the local, so called "specific" factors seem to be not adequate one should look for more general ones. It is shown, that such general factors as hormonal state of women' organism, preterm births, lactation, infertility treatment are important.


Assuntos
Neoplasias dos Genitais Femininos/terapia , Biomarcadores , Feminino , Neoplasias dos Genitais Femininos/diagnóstico , Humanos , Lactação/fisiologia , Imageamento por Ressonância Magnética , Prognóstico
10.
Blutalkohol ; 31(5): 273-314, 1994 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-7986482

RESUMO

Several thousand blood samples were taken from alcoholized drivers at the Blood Alcohol Examination Centre of the Institute of legal Medicine at Cologne University. These samples showed blood alcohol contents (BAC) as well as GGT, CDT, methanol, acetone and isopropanol levels which indicated alcohol addiction. The blood samples were selected by the drivers' ages and their BAC, but in some cases the GGT also played a role. In the majority of cases 1 or 2 parameters were measured. In 200 cases all four indicators were determined. The four parameters characterize a different problematic drinking behaviour. GGT characterizes chronic, long-term misuse, CDT characterizes occasional misuse, methanol characterizes current addicted drinking and acetone and isopropanol characterize metabolic disorders caused by alcohol. The importance of parameters is thoroughly discussed, also in relation to incorrectly measured positive values and the relation between alcohol consumption and -problems. Methanol values above 10 mg/kg, GGT activities above 100 U/l and CDT levels above 60 U/l provide sufficient proof of there being an alcohol problem which requires treatment. The levels of other indicators need not be above normal to determine this. The proportion of drivers under the influence of alcohol with problematic alcohol levels increases significantly when the BAC is above 2.0 per mille. However, there have been drivers with alcohol problems with lower BAC levels. DUI offenders addicted to alcohol are quite frequently over 40 years old. A correlation between the single indicators and the BAC is rarely found. If a correlation is to be found, it would be most likely with drivers whose BAC lies above 2.0 per mille. The mentioned indicators would detect an alcohol problem from the blood sample taken for the blood alcohol test. Alcohol problems may be detected and treated shortly after the DUI offence. This method is comparatively cheaper than medical-psychological-examinations as well as being based on objective and verifiable parameters.


Assuntos
1-Propanol/farmacocinética , Acetona/farmacocinética , Intoxicação Alcoólica/diagnóstico , Alcoolismo/diagnóstico , Condução de Veículo/legislação & jurisprudência , Metanol/farmacocinética , Transferrina/análogos & derivados , gama-Glutamiltransferase/sangue , Adolescente , Adulto , Consumo de Bebidas Alcoólicas/legislação & jurisprudência , Intoxicação Alcoólica/enzimologia , Alcoolismo/enzimologia , Etanol/farmacocinética , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Transferrina/metabolismo
11.
West J Med ; 137(5): 442, 1982 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18749253
12.
J Relig Health ; 13(1): 62-4, 1974 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24408293
13.
J Relig Health ; 13(4): 229-38, 1974 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24408630
14.
J Relig Health ; 12(3): 211-22, 1973 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24415071
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