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91.
Several theories have been proposed to generalise the concept of analytic continuation to holomorphic functions of the disc for which the circle is a natural boundary. Elaborating on Breuer-Simon’s work on right limits of power series, Baladi-Marmi-Sauzin recently introduced the notion of renascent right limit and rrl-continuation. We discuss a few examples and consider particularly the classical example of Poincaré simple pole series in this light. These functions are represented in the disc as series of infinitely many simple poles located on the circle; they appear, for instance, in small divisor problems in dynamics. We prove that any such function admits a unique rrl-continuation, which coincides with the function obtained outside the disc by summing the simple pole expansion. We also discuss the relation with monogenic regularity in the sense of Borel. 相似文献
92.
Giulio Maier 《Meccanica》1968,3(4):265-273
Summary For elastic perfectly plastic discretized structures acted upon by given loads and dislocations, it is shown, under holonomic constitutive laws or no local unloading hypothesis, that the formulation of the analysis problem in terms of finite (not incremental) stresses, is amenable to the Kuhn-Tucker conditions of a quadratic program. Then it is readily derived a generalized form of the principle of Haar and Kármán, together with an extremum theorem for displacements and plastic strains, which is the dual of the preceding one. As special cases of this theorems known variational principles follow, which thus turn out to be related in pairs by the duality notion as understood in programming theory. Also the statical and kinematical theorems of limit analysis are proved by means of the unitary conceptual framework supplied by quadratic programming.
The results presented here form part of a series of studies supported by the C.N.R. (National Research Council). 相似文献
Sommario Con riferimento a strutture discretizzate idealmente elastoplastiche, soggette a dati carichi e distorsioni, si mostra che nell'ipotesi di olonomia dei legami costitutivi o di assenza di ritorni elastici, la formulazione del problema strutturale negli sforzi finiti (non incrementali) è riducibile alle condizioni di Kuhn e Tucker di un programma quadratico. Se ne deducono direttamente una forma generalizzata del principio di Haar e Kármán ed un teorema di estremo negli spostamenti e nelle deformazioni plastiche, duale al precedente. Dai due teoremi discendono come casi speciali noti principi variazionali, che cosi risultano collegati in coppie dalla nozione di dualitá propria della teoria delle ottimizzazioni.Si mostra come anche i teoremi statico e cinematico del calcolo a rottura trovano una nuova dimostrazione nell'inquadramento teorico unitario fondato sulla programmazione quadratica.
The results presented here form part of a series of studies supported by the C.N.R. (National Research Council). 相似文献
93.
Giulio Ballio 《Meccanica》1968,3(3):177-186
Summary An elastoplastic beam-column model with one degree of freedom subjected statically to an on-center or off-center axial compressive force is considered. Its dynamic behavior in the elastoplastic range, resulting from a transverse periodic acting force in resonance with the structure in the elastic range, is examined. The principal features are highlighted by a phase plane study.
Sommario Si considera il modello a un grado di libertà di un'asta elastoplastica sollecitata staticamente da una forza assiale di compressione centrata o eccentrica. Si esamina il suo comportamento dinamico in campo elastoplastico per effetto di una forza trasversale periodica e in risonanza con la struttura in campo elastico, evidenziandone le principali caratteristiche attraverso lo studio nel piano delle fasi.相似文献
94.
Summary This paper proposes expressions of the dynamic pressure and of the transfer functions (response factors) between the dynamic pressure amplitude and the wave amplitude and between the dynamic pressure and the vertical displacement of the wave profile, for irrotational progressive gravity waves to third order approximation (non-linear theory).Some characteristic behaviours of the dynamic pressure and of the response factors are examined and compared with those of waves to first order approximation (linear theory).
相似文献
Sommario Si ricavano le espressioni della pressione dinamica per onde irrotazionali progressive di gravità al terzo ordine di approssimazione (modello non lineare).Si individuano le funzioni di trasferimento (fattori di risposta) sia tra l'ampiezza della pressione dinamica e l'ampiezza d'onda, sia tra la pressione dinamica e lo spostamento verticale della superficie di ondulazione.Si esaminano comportamenti caratteristici della pressione dinamica e dei fattori di risposta e si confrontano tali comportamenti con quelli relativi alle onde al primo ordine di approssimazione (modello lineare).
相似文献
95.
Giovanni Alberti Guy Bouchitté Pierre Seppecher 《Archive for Rational Mechanics and Analysis》1998,144(1):1-46
We make the connection between the geometric model for capillarity with line tension and the Cahn‐Hilliard model of two‐phase
fluids. To this aim we consider the energies where u is a scalar density function and W and V are double‐well potentials. We show that the behaviour of F
ε
in the limit ε→0 and λ→∞ depends on the limit of ε log λ. If this limit is finite and strictly positive, then the singular limit of the energies F
ε
leads to a coupled problem of bulk and surface phase transitions, and under certain assumptions agrees with the relaxation
of the capillary energy with line tension. These results were announced in [ABS1] and [ABS2].
(Accepted November 5, 1997) 相似文献
96.
Giulio Peruginelli 《代数通讯》2015,43(1):197-211
We describe an algorithm to compute the different factorizations of a given image primitive integer-valued polynomial f(X) = g(X)/d ∈ ?[X], where g ∈ ?[X] and d ∈ ? is square-free, assuming that the factorizations of g(X) in ?[X] and d in ? are known. We translate this problem into a combinatorial one. 相似文献
97.
Geninatti-Crich S Alberti D Szabo I Deagostino A Toppino A Barge A Ballarini F Bortolussi S Bruschi P Protti N Stella S Altieri S Venturello P Aime S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(30):8479-8486
The upregulation of low-density lipoprotein (LDL) transporters in tumour cells has been exploited to deliver a sufficient amount of gadolinium/boron/ligand (Gd/B/L) probes for neutron capture therapy, a binary chemio-radiotherapy for cancer treatment. The Gd/B/L probe consists of a carborane unit (ten B atoms) bearing an aliphatic chain on one side (to bind LDL particles), and a Gd(III)/1,4,7,10-tetraazacyclododecane monoamide complex on the other (for detection by magnetic resonance imaging (MRI)). Up to 190 Gd/B/L probes were loaded per LDL particle. The uptake from tumour cells was initially assessed on cell cultures of human hepatoma (HepG2), murine melanoma (B16), and human glioblastoma (U87). The MRI assessment of the amount of Gd/B/L taken up by tumour cells was validated by inductively coupled plasma-mass-spectrometric measurements of the Gd and B content. Measurements were undertaken in vivo on mice bearing tumours in which B16 tumour cells were inoculated at the base of the neck. From the acquisition of magnetic resonance images, it was established that after 4-6 hours from the administration of the Gd/B/L-LDL particles (0.1 and 1 mmol kg(-1) of Gd and (10)B, respectively) the amount of boron taken up in the tumour region is above the threshold required for successful NCT treatment. After neutron irradiation, tumour growth was followed for 20 days by MRI. The group of treated mice showed markedly lower tumour growth with respect to the control group. 相似文献
98.
Alberti A Fuochi P Guerra M Macciantelli D Torri G Valerio A Vismara E 《Organic & biomolecular chemistry》2011,9(9):3199-3204
Irradiation of a number of different sutures largely employed in the clinical practice with either high energy electrons or with γ-rays followed by quenching with glycidyl methacrylate (GMA) conveniently led to derivatization through a radical-based process. The radicals involved were detected by means of ESR spectroscopy and were characterized on the basis of their ESR spectral parameters which were also found to be consistent with the hfs constants predicted by DFT calculations. Evidence of the GMA derivatization of the sutures was obtained via(13)C CP-MAS NMR spectroscopy, while its extent was evaluated gravimetrically. 相似文献
99.
Capriotti AL Caracciolo G Cavaliere C Crescenzi C Pozzi D Laganà A 《Analytical and bioanalytical chemistry》2011,401(4):1195-1202
The knowledge about the interaction between plasma proteins and nanocarriers employed for in vivo delivery is fundamental
to understand their biodistribution. Protein adsorption onto nanoparticle surface (protein corona) is strongly affected by
vector surface characteristics. In general, the primary interaction is thought to be electrostatic, thus surface charge of
carrier is supposed to play a central role in protein adsorption. Because protein corona composition can be critical in modifying
the interactive surface that is recognized by cells, characterizing its formation onto lipid particles may serve as a fundamental
predictive model for the in vivo efficiency of a lipidic vector. In the present work, protein coronas adsorbed onto three
differently charged cationic liposome formulations were compared by a shotgun proteomic approach based on nano-liquid chromatography–high-resolution
mass spectrometry. About 130 proteins were identified in each corona, with only small differences between the different cationic
liposome formulations. However, this study could be useful for the future controlled design of colloidal drug carriers and
possibly in the controlled creation of biocompatible surfaces of other devices that come into contact with proteins into body
fluids. 相似文献
100.
Pettinari C Marchetti F Lupidi G Quassinti L Bramucci M Petrelli D Vitali LA da Silva MF Martins LM Smoleński P Pombeiro AJ 《Inorganic chemistry》2011,50(21):11173-11183
Five new silver(I) complexes of formulas [Ag(Tpms)] (1), [Ag(Tpms)(PPh(3))] (2), [Ag(Tpms)(PCy(3))] (3), [Ag(PTA)][BF(4)] (4), and [Ag(Tpms)(PTA)] (5) {Tpms = tris(pyrazol-1-yl)methanesulfonate, PPh(3) = triphenylphosphane, PCy(3) = tricyclohexylphosphane, PTA = 1,3,5-triaza-7-phosphaadamantane} have been synthesized and fully characterized by elemental analyses, (1)H, (13)C, and (31)P NMR, electrospray ionization mass spectrometry (ESI-MS), and IR spectroscopic techniques. The single crystal X-ray diffraction study of 3 shows the Tpms ligand acting in the N(3)-facially coordinating mode, while in 2 and 5 a N(2)O-coordination is found, with the SO(3) group bonded to silver and a pendant free pyrazolyl ring. Features of the tilting in the coordinated pyrazolyl rings in these cases suggest that this inequivalence is related with the cone angles of the phosphanes. A detailed study of antimycobacterial and antiproliferative properties of all compounds has been carried out. They were screened for their in vitro antimicrobial activities against the standard strains Enterococcus faecalis (ATCC 29922), Staphylococcus aureus (ATCC 25923), Streptococcus pneumoniae (ATCC 49619), Streptococcus pyogenes (SF37), Streptococcus sanguinis (SK36), Streptococcus mutans (UA159), Escherichia coli (ATCC 25922), and the fungus Candida albicans (ATCC 24443). Complexes 1-5 have been found to display effective antimicrobial activity against the series of bacteria and fungi, and some of them are potential candidates for antiseptic or disinfectant drugs. Interaction of Ag complexes with deoxyribonucleic acid (DNA) has been studied by fluorescence spectroscopic techniques, using ethidium bromide (EB) as a fluorescence probe of DNA. The decrease in the fluorescence of DNA-EB system on addition of Ag complexes shows that the fluorescence quenching of DNA-EB complex occurs and compound 3 is particularly active. Complexes 1-5 exhibit pronounced antiproliferative activity against human malignant melanoma (A375) with an activity often higher than that of AgNO(3), which has been used as a control, following the same order of activity inhibition on DNA, i.e., 3 > 2 > 1 > 5 > AgNO(3)? 4. 相似文献