The carbocyclic analog of cytidine,synthesis and antineoplastic activity

The carbocyclic analog (VI) of cytidine was prepared from the carbocyclic analog (I) of uridine. The intermediate stages were a tetrabenzoyl derivative of I, the tribenzoyl derivative of the uridine analog, and the tribenzoyl 4-chloropyrimidinone obtained from the latter derivative. The cytidine analog (VI) is active against KB cells in culture and against L1210 leukemia in mice. In the initial tests against L1210 leukemia, the highest dose (200 mg./kg./day, q.d. 1-9), of three active doses, increased lifespan by 82% and showed no evidence of toxicity.     

Destruction of carbonyl and hydroperoxide groups in oxidised polypropylene: Effect on photo-oxidation

The effect of destroying carbonyl and hydroperoxide groups in oxidised polypropylene on the subsequent rate of photo-oxidation has been examined using infra-red spectroscopy. The results show that carbonyl groups dominate the rate of photo-oxidation in severely oxidised polymer. In mildly oxidised polymer hydroperoxide groups control the rate, but to a much smaller extent. Destruction of the photo-active carbonyl and hydroperoxide groups in the unoxidised and oxidised polymers by prior photolysis in an inert atmosphere gave rise to some interesting and complex effects on subsequent photo-oxidation. The results indicate that although carbonyl and hydroperoxide groups may control the rates of photo-oxidation of thermally oxidised/processed polymer, their importance as primary photo-initiators is highly questionable. Oxygen-polymer charge transfer complexes appear to be the more likely photo-initiators.     

Thermodynamics of solids: Corrections from electron-phonon interactions

Anomalous room-temperature specific heats have been seen experimentally by Knapp and coworkers in highT _c superconductors. The measurements depart from 3N k _B + ₀ T by an amount of order ₀ T. We present a theory for this, based on the fact that electronphonon interactions cause both electron band energies _{k n} and phonon frequencies _{Q µ} to be weakly temperature-dependent. First an observation is made which we call Brook's Theorem: the shiftE _{k n} (Q µ) of the electron energy _{k n} due to adding one phonon in modeQ µ, is identical to the shift _{Q µ} (k n) of the phonon energy _Qµ due to adding one electron in the statek n. Second, we assert that to sufficient accuracy whenT> _D , entropy of the system of interacting electrons and phonons equals the entropy which would be calculated for non-interacting particles, except that theT-dependent energiesE _kn (T) and _{Q µ} (T) should be used. A proof to orderu ² (whereu is phonon displacement amplitude) was given in the thesis of one of us. Third, we use Brook's Theorem to show that the corrections C _el and C _ph to the specific heat due toT-dependence of electron and phonon energies respectively, are identically equal and have order of magnitude ₀ T. All these results are valid in adiabatic approximation to orderu ², and fail at low temperatures where non-adiabatic corrections are large.     

Nondiverging algebraically special ℋ-spaces

All nondiverging algebraically special -spaces are found by means of the complexified spin-coefficient formalism. The solutions are found to group naturally into two classes according to whether or not the optical-rotation spin coefficient vanishes.Research supported in part by a grant from the National Science Foundation.     

On the stabilizer subgroup of a fair of matrices

Let (F,G) be a pair of matrices defined over an arbitrary field, Fn × n, Gn × m. Consider the natural action of GL_n x GL_m on this pair given by (F,G) ? (gFg^-1,gGh^-1), where (g,h) ∈ GL_n × GL_m. This action is of interest in system theory as well as the representation theory of quivers. In this paper we study the stabilizer subgroup of this action stab(F,G), i.e.

$\text{{(g,h) ∈ GL}{}_{\mathrm{n}}\text{x GL}{}_{\mathrm{m}}\text{|gFg}{}^{-1}\text{= F,gGh}{}^{-1}\text{= G}}$

.     

An Integer Goal Programming Model for Determining Military Aircraft Expenditures

The decision-making process involved in the procurement of military weapon systems, although quite critical and complex, still encompasses the basic characteristics of a capital budgeting problem. Given a number of expenditure items and a limited budget, it is desired to procure those weapon systems that will achieve the goals and objectives of the government and/or military in the most efficient manner. Since these objectives are typically numerous and diverse, traditional decision-making techniques are not applicable. As such, integer goal programming is suggested as a technique to be employed to determine the number of military aircraft to be procured, given conflicting expenditure, budget and effectiveness goals. This method is demonstrated via a case example in which the solution results are presented.     

Effect of photochemical oxidation on polypropylene phosphorescence

Phosphorescence from polyolefins was studied from the aspects of excitation and emission wavelength and lifetime. Effects of photochemical oxidation on polypropylene phosphorescence are discussed in contrast to the effects of thermal oxidation.