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Non cylinder composite typ: prestressed concrete pipes extensively used in India for high pressure water supply lines are being designed at present by the conventional ‘analysis’ type structural design process. Geometric properties are assumed and then analysis is carried out, for checking accepted design behaviour or safe pressure carrying capacity. The authors here, have considered design behaviour at various loading stages and pressures, as an input in the design process called ‘synthesis’ and geometric properties are generated as an output. Optimal design solution is found using well known linear programming technique. Illustrative design example considering Veeranam Lake—Madras 230 km pipe line, shows substantial economy over conventionally designed pipes.

A new interatomic potential (MIST) which incorporates theoretical short-range repulsions and the entire long-range dispersion series is proposed. It is shown that MIST, which contains only one free parameter, retains all the advantages and overcomes some of the shortcomings of the Morse-6 hybrid potential. 15 sets of parameters for krypton are determined using second virail coefficient data to fix the free parameter. The sets of dispersion coefficients used include one set we have computed from relativistic wavefunctions. Independent tests of these potentials are made by comparing calculated and experimental viscosity and spectroscopic data. Agreement with experiment is found to be good.

Argon second and third virial coefficients for the recently proposed 14–12–8–6 potential are calculated and compared with experiment. The influence of the coefficients in the longrange dispersion energy on both of the virial coefficients is discussed.

This paper describes a new scheme for the protection of short transmission lines equipped with pilot wires. Tho relay scheme described employs semiconductor devices and works on impedance measurement. The effect of the complex nature of relaying current distribution factor ami attenuation and phase shift of the relayed signal are taken into consideration in the analysis. The expression for power swing is developed and swing loci are plotted. Finally the protection characteristics to cover the internal faults are suggested and two schematic arrangements to realize the necessary characteristics are described.

Argon viscosity coefficients and spectroscopic constants are calculated for the three-parameter potential of Smith and Thakkar. Good agreement with experiment is found. Parameters for krypton and xenon are determined by fitting to semi-empirical dispersion coefficients and experimental second virial coefficients. Viscosity coefficients for krypton and xenon are calculated as an independent test of the potentials so determined. Agreement with experiment is found to be good. The vibrational structure of the ground state of the krypton and xenon dimers is predicted from these potentials. It is concluded that this potential function is adequate for simultaneous correlation of dispersion, viscosity and second virial coefficients of the Noble gases and the vibrational energy levels of their dimers.

A representation of the long-range dispersion series proposed by Smith and Thakkar (1972) and rediscovered by LeRoy (1974) requires a choice of n or equivalently chi =C10C6/(C8)2. chi is nearly constant for interactions between pairs of S-state atoms. This constancy is explained in terms of the single oscillator model, the hydrogenic model and the Starkschall-Gordon model.

Calorimetric heats of solution in water and in 0·1 M-hydrochloric acid are presented for the 20 methyl and ethyl substituted hydrazines. Their difference is given as the heat of neutralization of each hydrazine. The base strengths (pKa) of these hydrazines were determined at five temperatures between 10 and 40° and at several ionic strengths, permitting extrapolation to values at zero ionic strength (pKa0) and calculation of the heats of ionization. An equation is presented by means of which the pKa0 data are correlated with a root mean square deviation ca. 0·15 pK unit in terms of inductive substituent constants (Taft σ*) and hydration parameters dependent on the number of hydrogens on each nitrogen of a hydrazinium ion. It is shown how the equation can be used to calculate heats of ionization, changes in heat capacity on ionization of amines and hydrazines, and equilibrium constants for tautomerization of hydrazinium ions. The changes in heat capacity appear to be only a function of the difference between the σ* constants for hydrogen and the substituents replacing it. Calculated equilibrium constants for the tautomerization: R1R2NHNR3R4⇌ R1R2NNHR3R4 are presented for 26 unsymmetrical hydrazines, including phenylhydrazine. Published pKa0 data for six oxyamines are correlated with a root mean square deviation of 0·08 pK unit.

The equation of motion of cylindrical shells is written using Donnell-Karman-Jenkins (DKJ) theory; and a Levy-type solution is used for computing their natural frequencies and model shapes. The method is applicable to shells simply supported on rigid traverses on the curved edges which have arbitrary support conditions along the longitudinal edges. Five cases of characteristic roots arise depending on the value of the natural frequency. Complete expressions for forces and displacements are presented for all the cases. The method has been used to compute the natural frequencies of a shell simply supported on all edges. Values are obtained that are identical with those obtained by the Navier type solution. A shell with edge beams has been analyzed. Its frequencies observed on a reinforced concrete shell roof model have been compared with theoretical values and found to agree closely.

Since two recent investigations revealed different structures for the one-electron reduced-density matrix (one matrix) of the Weiss wave function of the lowest ($^{2}P$) state of lithium, we have reanalyzed the Weiss wave functions for both the lowest $^{2}S$ and $^{2}P$ states of the three-electron ions. Although Weiss employed "$^{2}S$ restrictions" in the construction of his $^{2}P$ wave functions, their natural spin orbitals are not as spatially symmetry adapted as they are for the $^{2}S$ states.

(1973). ETHYLHYDRAZINE. THE FISCHER SYNTHESIS REVISITED. Organic Preparations and Procedures International: Vol. 5, No. 5, pp. 219-224.

A procedure is presented for determining the optimum arrangements of components in a system under weight or reliability constraints. It is based on reliability improvement through the use of functional redundancy. The mathematical background is briefly presented. General steps of the procedure are logically deduced and then applied to the components of an aerospace system.

Surface tension and light-scattering studies on aqueous solutions of sodium glycocholate gave CMC values of 0.0129 and 0.0138 mole/1., respectively. Light-scattering studies in 0.1 M NaCl gave a weight-average micellar weight of about 1950, indicating that four monomers of glycocholate aggregate to form the primary micelle. Preferential broadening of the angular methyl signals in the NMR spectra suggests that glycocholate micelles are formed by back-to-back hydrophobic association of the steroid nuclei. The signal due to the glycine methylene protons in the hydrophilic region of the molecule showed little broadening. Solubility studies showed that testosterone is solubilized by glycocholate below the apparent binary CMC. The solubilizing capacity is quite low. The complex association between testosterone and glycocholate suggests mixed micelle formation.

The solubility of testosterone in aqueous solutions of partially purified polysorbate 20, 40, and 60 was determined by measuring the area under the ultraviolet spectral peaks. There was solubilization below the critical micelle concentration. A linear relationship was observed between the amount of testosterone solubilized and the per cent polysorbate concentration. Polysorbate 60 exhibited the greatest solubilizing capacity and polysorbate 20 the least. The Z-value method for determining solvent polarity was employed to investigate the polarity of the environment in which testosterone was solubilized. At low polysorbate concentrations the Z-value was similar to that in water. As the polysorbate concentration increased, the Z-value decreased. This decrease in Z-value paralleled the increase in solubility of testosterone.

This note presents the solution to the problem of the absolute minimum volume of reinforcement for strength criterion. It is for the case of clamped square reinforced concrete slabs, using Hillerborg’s strip method and the necessary and sufficient conditions for an absolute minimum to exist as proposed by Rozvany and Charret based on the Prager and Shield hypothesis, for uncurtailed and curtailed reinforcement layouts.

The solution behavior of testosterone was studied with a view toward explaining an anomalous initial supersaturation observed in solubilized systems containing testosterone. This anomalous behavior was related to the conversion of an anhydrous crystal form of testosterone to a hydrate crystal form. The solution behavior of the anhydrous form was studied in several concentrations of polysorbate 20, dodecyltrimethylammonium bromide, and potassium laurate. In low concentrations of polysorbate 20 and potassium laurate, the time required to attain the solubility peak was less than that in distilled water. An increase in surfactant concentration resulted in a decrease in the solubility peak time. At higher concentrations, dodecyltrimethylammonium bromide exhibited a pattern similar to that of polysorbate 20 and potassium laurate; at a low concentration, however, a prolongation of the peak solubility time was noted.

Because presstressed concrete Vierendeel-type poles are cheaper than other types in India, millions are required to provide rural electrification. Using an optimal design for these repetitive-type components, considerable savings can be realized. The paper presents an optimal design using the Selected Active Constraints Technique (SACT), and a systematic synthesis. The direct design procedure is generated. Design behavior and loadings are treated as input and geometrical properties are systematically derived. The design procedure, based on SACT, requires extensive experience on the part of the design engineer, however, the calculations are simple. A design example is presented using physical data obtained from the Gujaret State Electricity Board (GEB), India, for a 8.53 m, 204 kg pole. Cost analysis is made, using prevailing prices in India, to show the economic gain obtained by the optimal design. The optimal design shows an economy of 18% in material cost per pole and 35% in high tensile wire weight, for the example considered.

The solubility of testosterone at 25° was determined in aqueous solutions containing varying concentrations of dodecyltrimethylammonium bromide (DTAB), hexadecyl-trimethylammonium bromide (HTAB), and potassium laurate (KL). After the initial stages of solubilization, a linear relationship was observed between the amount of testosterone solubilized and the molar concentration of the surfactant. The order of increasing solubilizing capacity was DTAB < HTAB < KL. The environment of solubilized testosterone, as investigated by the Z-value method, was found to be quite polar in all cases. At low concentrations of DTAB and HTAB the Z value was similar to that in water. As the concentration of the quaternary ammonium bromides increased, a precipitous drop in Z value, corresponding to a sudden decrease in environmental polarity, was observed in the region of the critical micelle concentration. With further increase in the concentration of DTAB and HTAB the Z value remained reasonably constant. In low KL concentrations the Z value of the testosterone environment was higher (more polar) than in water. With increasing concentrations of KL the Z value displayed behavior similar to that in DTAB and HTAB. In general, solutions of ionic surfactants showed higher Z values than those of the nonionic surfactants examined previously.

6- and 7-Nitro-2-benzyl-3H-4-ketoquinazolines and their 3-Me and 3-Ph derivatives were prepared by condensing the 6-nitro (III) and 7-nitro (XII) derivatives of -4H-3,1-benzoxazin-4-one with ammonia, methylamine and aniline, respectively. The compounds III and XII were formed on refluxing 5- and 4-nitro-N-phenylacetylanthranilic acids with acetic anhydride. 6- and 7-Nitro-2-benzyl-3H-4-ketoquinazolines (IV and XIII) were also prepared by condensing 5- and 4-nitro-N-phenylacetylanthranilic acids with formamide, respectively, in very low yields. The compounds IV and XIII yielded the corresponding 2-benzoyl derivatives on oxidation and the corresponding 2-(1-phenylstyryl) derivatives on reaction with benzaldehyde. 6- and 7-Nitro-2-styryl and 2-(1-phenylstyryl)-3H-4-ketoquinazolines were not oxidized by alkaline permanganate. UV spectra of these compounds have been studied.

Bei der Oxydation von gewissen β-Ketocarbonsaureestern und β-Diketonen in Chloroform mit Benzoepersaure entstehen Endiole, bzw. ihre tautomeren Carbonylformen, die wahrscheinlich aus primar gebildeten Epoxyden durch Umlagerung hervorgehen. So wurden aus Dibenzoylmethan Dibenzoylcarbinol bzw. 1-Phenyl-2-benzoyl-athen-1,2-diol, aus Acetessigsaureathylester 2,3-Dioxy-buten-(2)-saureathylester (III) und aus Benzoylessigsaureathylester α-Oxybenzoylessigsaure-athylester bzw. α, β-Dioxyzimtsaure-athylester (VIII) gebildet.

The dynamic behavior of cylindrical tanks in the empty or water-filled condition is analyzed. The equation of free vibration is derived for tanks fixed at the base and free at the top by using Lagrange’s equation in which the various energy expressions are worked out on the basis of assumed beam-type functions for the displacements of the shell. Equations are finally derived for natural time periods, mode shapes, and the virtual mass factor of water which may be used for obtaining the response of the tank to superimposed dynamic forces. The effects of length-radius ratio and varying water depth on the natural frequencies are studied by numerical examples.

The interaction of theophylline with sodium benzoate was examined by NMR to understand the mode of interaction. Chemical shifts of theophylline protons were determined as a function of sodium benzoate concentration in D2O at 30°. Several different concentrations of theophylline were used. Signals of both methyl groups undergo significant upfield shifts, indicating vertical or plane-to-plane stacking.

A new three-parameter intermolecular potential function with the correct asymptotic behaviour at large intermolecular separations is proposed. Preliminary parameters for argon are determined by fitting to the available semi-empirical values of the dispersion coefficients and to experimental second virial coefficients.