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1.
Z. B. Alfassi F. Groppi M. L. Bonardi O. Presler U. German 《Journal of Radioanalytical and Nuclear Chemistry》2006,268(3):639-640
Summary The paper deals with the common mistake of interpolating calculation of the efficiency of gamma-detectors by the inverse square
law of the distance of the source from the detector cap and suggests the use of the distance from the virtual point detector
instead. 相似文献
2.
M. L. Bonardi C. Birattari F. Groppi L. Gini H. S. C. Mainardi 《Journal of Radioanalytical and Nuclear Chemistry》2004,259(3):415-419
Radionuclides of very high specific activity A
S(t) have great relevance for applications in the life sciences. Updated definitions of A
S are given. The real A
S(t) must be measured by analytical and radioanalytical techniques. No-carrier-added (NCA) radionuclides have A
S(NCA) sometimes close to the carrier-free (CF) value A
S(CF). The accurate knowledge of excitation functions of nuclear reactions vs. ion beam energy is mandatory to maximize A
S(NCA); the minimization of isotopic dilution factor IDF(t) has been achieved too. A range of accelerator production and radioanalytical QC methods for A
S(NCA) optimization and determination is presented.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
3.
Fabien Tricoire 《4OR: A Quarterly Journal of Operations Research》2007,5(2):165-168
We present an overview of the author’s Ph.D. thesis, supervised by P. Dejax and N. Bostel, which was defended in February
2006 at école des Mines de Nantes, France. The thesis is written in French, and is available at . It was conducted in the context of a research contract with a water distribution company. In a first section, we define
multiperiod routing problems for service technicians. In a second section, we present some heuristics and a memetic algorithm
used to solve these problems. The third section introduces optimal and near-optimal approaches based on column generation.
Finally, we present some applications to the real-life case. The methods presented in Sects. 2, 3 and 4 were tested over several
sets of problems, based on real-life statistics provided by the company.
相似文献
4.
Moraes ML Bonardi C Mendonça CR Campana PT Lottersberger J Tonarelli G Oliveira ON Beltramini LM 《Colloids and surfaces. B, Biointerfaces》2005,41(1):15-20
The study of interactions between biological molecules and model membranes is essential for the understanding of a number of physiological mechanisms involved in viral infections and dissemination. In this paper, the analysis of the interaction between a peptide from the p24 protein of Human Immunodeficiency Virus type 1 (HIV-1) and a phospholipid monolayer has pointed to a cooperative response in which very small amounts of peptide p24-1 (e.g. 0.05 mol%) can lead to measurable effects. Monolayer surface pressure and surface potential isotherms were affected for peptide concentrations as low as 0.05 mol%, with saturation at 0.5 mol%. The expansion effect from p24-1 is confirmed by changes in morphology of the monolayers using Brewster angle microscopy. Even though p24-1 is disordered in aqueous solutions, the interaction with dipalmitoyl phosphatidylcholine (DPPC) causes it to adopt an alpha-helix structure, as shown by circular dichroism (CD) data for multilamellar vesicles (MLV). The expansion of the phospholipid monolayer in a cooperative way may imply that p24-1 has potential antiviral activity, by participating in the cell rupture, with no need of specific receptors in the membrane. 相似文献
5.
Justum Y Gatti F Lauvergnat D Nauts A Chapuisat X 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(4):649-661
For high values of the quantum number of the total angular momentum J (up to J = 20), quantum mechanical eigenstates (eigenvalues and eigenfunctions) are calculated by the method of Gatti et al. (J. Mol. Spectrosc. 181 (1997) 403) for the bending deformations of HCN and CNH. In particular, we have examined the l-type resonances in highly excited rovibrational states within the framework of a one-dimensional model, i.e. along the reaction pathway for the isomerization reaction HCN/CNH. The potential energy surface used is that of Bowman et al. (J. Chem. Phys. 99 (1993) 308). 相似文献
6.
L. Goetz E. Sabbioni E. Marafante J. Edel-Rade C. Birattari M. Bonardi 《Journal of Radioanalytical and Nuclear Chemistry》1981,67(1):183-192
Carrier-free201+202Tl have been produced in the cyclotron by (p, xn) reactions on mercury targets and used as a trcer for thallium in metallobiochemistry
of heavy metal pollution. The separation of201+202Tl radioisotopes from Hg involved a solvent extraction method leading to labelled univalent Tl(I) ions. This radioactive solution
was used to prepare different201+202Tl labelled compounds such as inorganic Tl(III) ions and organic dimethylthallium. Quality controls have been applied directly
on the different radioactive solutions immediately before their administrations to rats in order to ensure that thallium had
the chemical form expected. A summary of the main results concerning different aspects of the metabolic investigations on
rats such as absorption, retention, excretion, transplacental transport and influence of the different chemical forms of thallium
on its metabolism is also reported. 相似文献
7.
D. Bagatti M. C. Cantone A. Giussani S. Ridone C. Birattari M. L. Bonardi F. Groppi A. Martinotti S. Morzenti M. Gallorini E. Rizzio 《Journal of Radioanalytical and Nuclear Chemistry》2005,263(2):515-520
Summary The nuclear properties of 186gRe make it a useful agent for radionuclide therapy and imaging. The coordination compound [186gRe]Re-HEDP has proved to be a successful bone seeking agent for palliation of metastatic bone pain. Chemical, radiochemical and radionuclidic purity of commercial radiopharmaceutical [186gRe]Re-HEDP have been checked by means by γ- and β-spectrometries, INAA and paper radio-chromatography. The results indicate a good radionuclidic purity, with levels of contamination from the short-lived 188Re well below the required specifications. After injection of the radiopharmaceutical, the radiochemical measurements conducted in vivo, on biological matrices, blood, plasma and urine, have shown that, entering the systemic circulation, 186gRe dissociates from the bis-phosphonate complex as hydrosoluble [186gRe]ReO4-, and the two chemical species follow different biokinetics. 相似文献
8.
Fabien Fontaine Evan Bolton Yulia Borodina Stephen H Bryant 《Chemistry Central journal》2007,1(1):12-14
Background
Large chemical databases require fast, efficient, and simple ways of looking for similar structures. Although such tasks are now fairly well resolved for graph-based similarity queries, they remain an issue for 3D approaches, particularly for those based on 3D shape overlays. Inspired by a recent technique developed to compare molecular shapes, we designed a hybrid methodology, alignment-recycling, that enables efficient retrieval and alignment of structures with similar 3D shapes. 相似文献9.
Excitation functions fornatZn (p, xn) and (p, pxn) nuclear reactions in the 5–45 MeV proton energy range were measured. Evaluations were made both of
target thickness and proton energy in order to optimize the67Ga production rate, at the same time minimizing contamination by the66Ga. Optimal irradiation conditions, depending both on the beam current available and on the power dissipated into the target
were determined. 相似文献
10.
Mangeney C Ferrage F Aujard I Marchi-Artzner V Jullien L Ouari O Rékaï el D Laschewsky A Vikholm I Sadowski JW 《Journal of the American Chemical Society》2002,124(20):5811-5821
Citrate-capped gold nanoparticles as well as planar gold surfaces can be efficiently grafted with a covalently attached polymer monolayer a few nanometers thick, by simple contact of the metal surface with dilute aqueous solutions of hydrophilic polymers that are end-capped with disulfide moieties, as shown by UV/vis absorption, dynamic light scattering, and surface plasmon resonance studies. The hydrophilic polymer-coated gold colloids can be freeze-dried and stored as powders that can be subsequently dissolved to yield stable aqueous dispersions, even at very large concentrations. They allow for applying filtrations, gel permeation chromatography, or centrifugation. They do not suffer from undesirable nonspecific adsorption of proteins while allowing the diffusion of small species within the hydrogel surface coating. In addition, specific properties of the original hydrophilic polymers are retained such as a lower critical solution temperature. The latter feature could be useful to enhance optical responses of functionalized gold surfaces toward interaction with various substrates. 相似文献