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1.
The structure of aqueous solutions of two polyoxyethylene non-ionic amphiphiles, C10E5 and C8E4, is studied by small-angle neutron-scattering along isothermal paths crossing the isotropic single-phase region from 0% to 100% amphiphile volume fractions. The scattered intensityI(k) shows a peak at a valuek m , which grows monotonically as the amphiphile volume fraction increases. The interpretation of the scattering data lead to the following conclusion: as increases the micellar structure becomes less and less sharp, but some orientational correlations between neighboring amphiphile molecules are preserved even in the pure amphiphile phase.  相似文献   
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Photodynamic therapy (PDT) with porphyrins and red light is receiving increasing attention in the management of malignant tumours. At present PDT is primarily indicated for the treatment of superficial or early-stage lesions. At the Department of Radiotherapy and the First Institute of Surgery in Padova (Italy) more than 150 cases of tumours of different types have been treated using this technique. This paper briefly describes 21 cases of superficial oesophageal cancer. A complete response was observed in 11 of 21 cases. Radiation therapy appeared to be very effective as a salvage treatment of non-response patients.  相似文献   
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Chromatographic retention data and thermodynamic properties of six pine terpenes (α-pinene, β-pinene, camphene, limonene, α-phellandrene and p-cymene) on six different liquid phases, with a wide range of polarity, are reported at temperatures from 80 to 120 °C. The retention behaviour and selectivity of liquid phases for the separation of binary solute systems are discussed in terms of activity coefficients and specific interactions. Solubility parameters for the liquid phases are reported using the regular solution theory and the Takamiya equation and a good correlation between polarity and solubility parameters is observed.  相似文献   
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An extensive study has been carried out in order to evaluate the possible use of the perfluoropolyether fluids, obtained from HFP photooxidation and specially purified and selected, as lubricants or vacuum working fluids, in presence of UF6.Some physicochemical properties are reported and the results of the tests experienced on perfluoropolyether cuts put into contact with UF6, in different conditions for long aging time at high temperature in presence of some typical engineering materials.The results, shown in this work, allowed a verification of the long term compatibility of the perfluoropolyether special fractions against UF6 at temperatures up to 130°C.These results still offer a contribution in order to solve some technological problems on UF6 processing.  相似文献   
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Pugi  Luca  Reatti  Alberto  Corti  Fabio 《Meccanica》2019,54(1-2):321-331
Meccanica - Wireless recharge of electric vehicles is an important field of research. Design of inductive power transfer systems involves the optimization of resonant coils coupled through mutually...  相似文献   
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The ligand–macromolecule interaction is analysed in terms of selective (R1SE) and non-selective (R1NS) spin–lattice relaxation rates, considering the contribution arising from all possible specific and non-specific receptor sites. A linear relation between ΔR1SE and macromolecule concentration is demonstrated to exist under any coordination conditions. The slope of the straight line obtained is defined as the ‘affinity index' which is proposed as a general criterion for assessing the total ability of a ligand to interact with a macromolecule.  相似文献   
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The title refers to the nilcommutative or NC-schemes introduced by M. Kapranov in Noncommutative Geometry Based on Commutator Expansions, J. Reine Angew. Math 505 (1998) 73–118. The latter are noncommutative nilpotent thickenings of commutative schemes. We also consider the parallel theory of nil-Poisson or NP-schemes, which are nilpotent thickenings of commutative schemes in the category of Poisson schemes. We study several variants of de Rham cohomology for NC- and NP-schemes. The variants include nilcommutative and nil-Poisson versions of the de Rham complex as well as of the cohomology of the infinitesimal site introduced by Grothendieck in Crystals and the de Rham Cohomology of Schemes, Dix exposés sur la cohomologie des schémas, Masson, Paris (1968), pp. 306–358. It turns out that each of these noncommutative variants admits a kind of Hodge decomposition which allows one to express the cohomology groups of a noncommutative scheme Y as a sum of copies of the usual (de Rham, infinitesimal) cohomology groups of the underlying commutative scheme X (Theorems 6.1, 6.4, 6.7). As a byproduct we obtain new proofs for classical results of Grothendieck (Corollary 6.2) and of Feigin and Tsygan (Corollary 6.8) on the relation between de Rham and infinitesimal cohomology and between the latter and periodic cyclic homology.  相似文献   
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