Ranking and unranking of B-trees

Algorithms are presented for the ranking, unranking, and generation of all B-trees of order m with n leaves. The algorithms take time proportional to the sizes of their output. It is shown how a search graph can be constructed to aid in the ranking and unranking of B-trees.     

Neutral current effects in the parity violating nuclear force

The measurements of the ΔI = 1 part of the parity violating nuclear force when combined with information on neutral current couplings from neutrino scattering and pion production experiments allow an estimate of the isoscalar admixture in the neutral current if it has a vector axial-vector structure has been shown.     

Modules with cyclic support

Periodica Mathematica Hungarica -     

Effect of shear rate on the rate of radical polymerization of methyl methacrylate

The effect of shear rate on the radical polymerization of methyl methacrylate at 50°, in bulk as well as in solution, has been studied. The rate of polymerization increases by as much as 15% at high shear rates. This increase is explained in terms of changes in the initiator efficiency with shear rate.     

An Indian form of third order Taylor series approximation of the sine

The paper describes an approximation formula for sine (x + h) that differs from the first four terms of the Taylor expansion only by having 4 in place of 6 in the denominator of the fourth term. It appears in Sanskrit stanzas quoted in a work of about the fifteenth century and given here with translation and explanation.     

Biosynthesis of tetrahydropalmatine and palmatine

The incorporation of (±)-norlaudanosoline, norprotosinomenine, nororientaline, norlaudanidine, reticuline and laudanosine into tetrahydropalmatine and palmatine has been studied, and specific utilization of reticuline demonstrated. Feeding of (±)-[N-methyl-¹⁴C] reticuline showed that C atom 8 of tetrahydropalmatine and palmatine are formed by oxidative cyclisation of the N-Me group of reticuline. Parallel experiments with (R)-; and (S)-, reticulines demonstrated specific incorporation of (R)- isomer into these bases. Feeding experiments also revealed that the plants can convert tetrahydropalmatine into palmatine with high efficiency.     

Die Wechselwirkung zwischen Chlorwasserstoffgas und Äthanol in flüssiger Phase unter den Einfluß von Wechselstromfeldern, 2. Mitt.

Zusammenfassung Während eine in einenSiemens-Ozonisator gefüllte Alkohol-HCl-Mischung auch nach 6stdg. Behandlung mit Wechselstrom von 50 bzw. 500 Hz und 12 bis 15 kV praktisch unverändert bleibt, bilden sich bei der Einwirkung von Wechselstrom auf Alkohol-HCl-Mischungen in U-förmigen oder zylindrischen Elektrolysenzellen chlorierte und nicht-chlorierte Oxydationsprodukte des Alkohols in Abhängigkeit vom Elektrodenmaterial (Platindraht und Kohlestäbchen). Die Abhängigkeit der Natur der Reaktionsprodukte vom Elektrodenmaterial wird diskutiert.1. Mitt.:P. C. Gupta, Naturwiss.46, 261 (1959).