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61.
Tito Chella 《Annali di Matematica Pura ed Applicata》1924,1(1):199-218
Nel presentare ai Lettori questo lavoro, annunciamo con vivo rammarico che l'autore prof.Tito Chella è mancato ai vivi nell'ottobre scorso (1923) a soli 42 anni. Il Chella percorse gli stud? Universitarii in Pisa come allievo
della R. Scuola Normale Superiore, presso cui si abilitò con una tesi:Sugli invarianti integrali, pubblicata nel Vol. XI (1908) degli Annali di questa Scuola. Fu valoroso insegnante di matematiche, prima nella Scuola Tecnica
di Spezia, poi negli Istituti Tecnici di Foggia, Bari, Firenze e da ultimo in quello di Pisa. Pure aggravato dall'insegnamento
secondario, e di salute mal ferma, Egli ha continuato ad occuparsi di studi e ricerche proprie. Il presente lavoro è soltanto
un primo saggio di ricerche sulla teoria dei numeri algebrici, che egli aveva avviato con promettente successo, e che vennero
malauguratamente interrotte dalla morte.La Direzione 相似文献
62.
Nagarajan Amirtha Seshaiyer Viswanathan Ramachandran Ganesan 《Monatshefte für Chemie / Chemical Monthly》1984,115(1):35-43
The kinetics of the addition of iodine monochloride (ICl) to some vinyl compounds in nitrobenzene solvent was investigated. In all cases the reaction follows second order dependence on ICl and first order on the substrate, making the total order three. Rate constants were measured for each substrate at 20°, 30°, 40° and 50°C.Arrhenius plots were made from which activation energies were evaluated. Other kinetic and thermodynamic parameters are reported. A suitable mechanism is proposed for the reaction and based on this, the various parameters are discussed. Solvent effects are discussed and the data with nitrobenzene and acetic acid solvents are compared.
Kinetik und Mechanismus der Addition vonICl zu einigen Alkenen in Nitrobenzol als Lösungsmittel. Effekt der Polarität des Lösungsmittels
Zusammenfassung Die Kinetik der Addition von ICl zu einigen Vinylverbindungen in Nitrobenzol als Lösungsmittel wurde untersucht. In allen Fällen ist die Reaktion von zweiter Ordnung hinsichtlich ICl und von erster Ordnung hinsichtlich des Substrats, d. h. mit einer Gesamtordnung von drei. Geschwindigkeitskonstanten wurden für jedes Substrat bei 20°, 30°, 40° und 50°C gemessen. AusArrhenius-Diagrammen wurden Aktivierungsenergien ermittelt und auch andere kinetische und thermodynamische Parameter wurden bestimmt. Ein Mechanismus wird vorgeschlagen, wobei die verschiedenen Parameter diskutiert werden. Lösungsmitteleffekte werden ebenfalls diskutiert und die Daten mit Nitrobenzol und Essigsäure als Lösungsmittel miteinander verglichen.相似文献
63.
64.
A.R. Sweedler S. Moehlecke R.H. Jones R. Viswanathan D.C. Johnston 《Solid State Communications》1977,21(11):1007-1009
The effect of high energy neutron irradiation (E>1 MeV) on the superconducting transition temperature, Tc, of the A-15 compound Mo3Os is reported. Tc was found to decrease with increasing neutron dose, but at a rate considerably less than observed in other A-15 compounds composed of non-transition metals. The results lend support to the idea that the effect of ordering on Tc is smaller for A-15 compounds composed only of transition metals than those composed of transition and non-transition metals. 相似文献
65.
66.
S Y Su G K Shiu J Simmons C T Viswanathan J P Skelly 《Biomedical chromatography : BMC》1992,6(6):265-268
Six estrogens-estrone, equilin, estradiol, sodium estrone sulphate, sodium equilin sulphate and sodium 17-alpha-dihydroequilin sulphate in dog serum were successfully separated and quantified by a high performance liquid chromatographic method developed in our laboratories. The mobile phase was optimized by studying the effects of an organic modifier (acetonitrile) and an ion pairing reagent (tetrabutylammonium hydroxide). The serum sample work-up procedure was designed to recover both conjugated and unconjugated estrogens. The optimum method involved acetonitrile to precipitate serum proteins/peptides and extract estrogens. Residues were reconstituted in 50% acetonitrile in water for injection. The detection limits for these six estrogens via UV detection ranged from 0.5 to 5 ng on-column with a signal-to-noise ratio (S/N) of 10 for a 20 microL injection and via fluorescence 0.1 ng on-column for 17-beta-estradiol. Validation data are included for all six estrogens. 相似文献
67.
An emission system of I2 in Ar in the region 2830–2890 Å is examined under high resolution and found to display fine violet-degraded band structure. This system is interpreted as a charge-transfer transition originating from an ion-pair state near 47 000 cm?1 and terminating on a weakly bound state which dissociates to two ground-state atoms. This interpretation is supported by spectral simulations employing a bound-free model. The transition is tentatively assigned as , according to which the excited state becomes the fourth ion-pair state near 47 000 cm?1 to be experimentally characterized, and the lower state is the last component of the lowest 3Π state to be identified. The vibrational assignments include about 45 bands in 127I2 and 129I2, spanning v′ = 0–4 and v″ = 6–19, but with the numbering of the lower state remaining uncertain by several units. The main spectroscopic constants for the excited state are Te = 47 070 cm?1, ?e = 105.7 cm?1, ?exe = 0.49 cm?1. The spectral simulations place the lower state's potential curve 34 650 cm?1 below the upper state at R = R′e, with slope ?850 cm?1/Å. For our “best” numbering of the lower state, ?e = 20.5 cm?1, ?exe = 0.29 cm?1, Te = 12 190 cm?1, and De = 360 cm?1. 相似文献
68.
We show that certain known singular solutions for pure SU(3) Yang-Mills theory carry magnetic charges with respect to both U(1) subgroups of SU(3). A topological characterisation in terms of monopoles is given to the SU(2) singular solutions of Wu and Yang. 相似文献
69.
The paper discusses the solution to an elastodynamic problem of an infinite medium excited by loads acting over a semi-infinite rectangular boundary whose height 2a is assumed small compared to the wavelengths of interest. The solution is developed using the method of matched-asymptotics in conjunction with an application of the Wiener-Hopf technique for the outer problems and the Muskhelishvili-Kolosov complex functions for the inner problems. The solutions are matched mutually and the resulting stress behaviour, as far as it is described by the inner limit to the outer solution, is also derived. 相似文献
70.
R. Viswanathan A.C. Lawson C.S. Pande 《Journal of Physics and Chemistry of Solids》1976,37(3):341-343
The low temperature heat capacity data of a small bulk sample of LaRu2 show that the structural transformation occurring at Tm ~ 29.5K is rather spread out. The electronic heat capacity coefficient, γ, and Debye temperature, θD, are found to be respectively . atom K2 and 164 K. The multiple anomalies below Tm and Tc (4.45 K) are discussed. 相似文献