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101.
de Oliveira Tamires D. Cabeza Natália A. da Silva Gelson T. S. T. Ruiz Ana L. T. G. Caires Anderson R. L. da Silveira Rafael G. Rodrigues Daniela C. M. Fiorucci Antônio R. dos Anjos Ademir 《Transition Metal Chemistry》2021,46(2):111-120
Transition Metal Chemistry - Lapachol is a natural naphthoquinone known for having a variety of biological properties, and in recent years, it has been used in the synthesis of metal complexes with... 相似文献
102.
M. C. Fujiwara G. Andresen W. Bertsche A. Boston P. D. Bowe C. L. Cesar S. Chapman M. Charlton M. Chartier A. Deutsch J. Fajans R. Funakoshi D. R. Gill K. Gomberoff J. S. Hangst W. N. Hardy R. S. Hayano R. Hydomako M. J. Jenkins L. V. Jørgensen L. Kurchaninov N. Madsen P. Nolan K. Olchanski A. Olin R. D. Page A. Povilus F. Robicheaux E. Sarid D. M. Silveira J. W. Storey R. I. Thompson D. P. van der Werf J. S. Wurtele Y. Yamazaki 《Hyperfine Interactions》2006,172(1-3):81-89
ALPHA is an international project that has recently begun experimentation at CERN’s Antiproton Decelerator (AD) facility.
The primary goal of ALPHA is stable trapping of cold antihydrogen atoms with the ultimate goal of precise spectroscopic comparisons
with hydrogen. We discuss the status of the ALPHA project and the prospects for antihydrogen trapping. 相似文献
103.
104.
P. P. Monteiro H. L. Castro J. Castro R. Luí s D. Fonseca J. Pedro L. Pellegrino M. Hajduczenia S. Pato N. Garcia C. Santiago T. Silveira A. Ferreira 《Fiber and Integrated Optics》2005,24(3):395-410
This article summarizes the research activities carried out by the R&D Optical Networks Communications group (COM RD1), at Siemens S.A., in collaboration with both universities and other research institutes. These activities cover various aspects of advanced modulation formats, all optical wavelength conversion, optical quality of signal monitoring in transparent WDM networks, routing, and wavelength assignment in optical networks. 相似文献
105.
A Soibel SS Banerjee Y Myasoedov ML Rapparort E Zeldov S Ooi T Tamegai 《Pramana》2002,58(5-6):893-898
Using a novel differential magneto-optical imaging technique we investigate the phenomenon of vortex lattice melting in crystals
of Bi2Sr2CaCu2O8 (BSCCO). The images of melting reveal complex patterns in the formation and evolution of the vortex solid-liquid interface
with varying field (H)/temperature (T). We believe that the complex melting patterns are due to a random distribution of material disorder/inhomogeneities across
the sample, which create fluctuations in the local melting temperature or field value. To study the fluctuations in the local
melting temperature/field, we have constructed maps of the melting landscape T
m(H, r), viz., the melting temperature (T
m) at a given location (r) in the sample at a given field (H). A study of these melting landscapes reveals an unexpected feature: the melting landscape is not fixed, but changes rather
dramatically with varying field and temperature along the melting line. It is concluded that the changes in both the scale
and shape of the landscape result from the competing contributions of different types of quenched disorder which have opposite
effects on the local melting transition. 相似文献
106.
A Gurtu P K Malhotra I S Mittra P M Sood SC Gupta VK Gupta GL Kaul LK Mangotra Y Prakash NK Rao ML Sharma 《Pramana》1974,3(5):311-322
This is a continuation of our earlier investigation (Gurtuet al 1974Phys. Lett. 50 B 391) on multiparticle production in proton-nucleus collisions based on an exposure of emulsion stack to 200 GeV/c beam at the NAL. It is found that the ratioR em = 〈n s〉/〈n ch〉, where 〈n ch〉 is the charged particle multiplicity in pp-collisions, increases slowly from about 1 at 10 GeV/c to 1·6 at 68 GeV/c and attains a constant value of 1·71 ± 0·04 in the region 200 to 8000 GeV/c. Furthermore,R em = 1·71 implies an effectiveA-dependence ofR A =A 0.18,i.e., a very weak dependence. Predictions ofR em on various models are discussed and compared with the emulsion data. Data seem to favour models of hadron-nucleon collisions in which production of particles takes place through adouble step mechanism,e.g., diffractive excitation, hydrodynamical and energy flux cascade as opposed to models which envisage instantaneous production. 相似文献
107.
108.
Cluster emission and chemical reactions in oxygen and nitrogen ices induced by fast heavy-ion impact
Ponciano CR Martinez R Farenzena LS Iza P Homem MG Naves de Brito A Wien K da Silveira EF 《Journal of mass spectrometry : JMS》2008,43(11):1521-1530
Two ices, O2 and a mixture of O2 and N2, are bombarded by 252Cf fission fragments (FF) (approximately 65 MeV at target surface); the emitted positive and negative secondary ions are analyzed by time-of-flight mass spectrometry (TOF-SIMS). These studies shall enlighten sputtering from planetary and interstellar ices. Three temperature regions in the 28-42-K range are analyzed: (1) before N2 sublimation, in which hybrid chemical species are formed, (2) before O2 sublimation, in which the TOF mass spectrum is dominated by low-mass (O2)p cluster ions and (3) after O2 sublimation, in which (N2)p or (O2)p cluster ions are practically inexistent. In the first region, four hybrid ion series are observed: NOn-1+, N2On-2(+/-), and N4On-4(-). In the second region, two positive and negative ion series are identified: (O2)pO(+/-) and (O2)pO2(+/-). Their yield distributions are fitted by the sum of two decreasing exponentials, whose decay constants are the same for all series. It is observed that the cluster ion desorption from solid oxygen is very similar to that of other frozen gases, but its yield distribution oscillates with a three- or six-atom periodicity, suggesting O3 or 3O2 units in the cluster structure, respectively. 相似文献
109.
da Silva VB Kawano DF Gomes Ada S Carvalho I Taft CA da Silva CH 《The journal of physical chemistry. A》2008,112(38):8902-8910
In this work, we have used molecular dynamics, density functional theory, virtual screening, ADMET predictions, and molecular interaction field studies to design and propose eight novel potential inhibitors of CDK2. The eight molecules proposed showed interesting structural characteristics that are required for inhibiting the CDK2 activity and show potential as drug candidates for the treatment of cancer. The parameters related to the Rule of Five were calculated, and only one of the molecules violated more than one parameter. One of the proposals and one of the drug-like compounds selected by virtual screening indicated to be promising candidates for CDK2-based cancer therapy. 相似文献
110.
Bode P Bueno MI Bortoleto GG Hoffmann G van den Ingh TS Rothuizen J 《Analytical and bioanalytical chemistry》2008,390(6):1653-1658
The heritability of chronic hepatitis in the Labrador Retriever is studied with the aim of identifying the related gene mutation.
Identification of cases and controls is largely based on instrumental neutron activation analysis (INAA) Cu determination
in liver biopsies. The burden for these companion animals may be reduced if nail clippings and hair (fur) could serve as a
noninvasive indicator for the hepatic Cu concentrations. No correlation was found between hepatic Cu concentrations and Cu
concentrations in hair and nail samples. However, hair and nail samples were also analyzed by X-ray tube excitation, taking
advantage of the X-ray Compton, Rayleigh, and Raman scattering which reflects the organic components such as the type of melanin.
Principal component analysis provided first indications that some differentiation between healthy and sick dogs could indeed
be obtained from hair and nail analysis.
Figure Principal component analysis of scattered region of x-ray fluorescence spectra of Labrador dog nails, demonstrating the differentiation
towards dogs with high and low Cu liver levels (respectively positive and negative PC2 values) reflecting hepatitis, as well
as gender (PC1: negative values for female and positive values for males) 相似文献