The world distribution of commercial energy consumption

Inequality in the world distribution of income has been widely studied. A related problem is the worldwide maldistribution of per capita energy consumption. This article examines trends in the international distribution of energy use over the period 1950–1975. Lorenz curves are used to show that during this 25-year period inequalities in energy consumption have decreased slowly. Most of this redistribution has however occurred among countries in the top 30% of energy consumers. Of the remaining countries only China has significantly increased its per capita consumption. If China is excluded 60% of the world's population accounts for only 10% of total world consumption. This imbalance has remained unaltered since 1950.     

The Influence of C60 Powders On Cultured Human Leukocytes

In order to check its possible acute toxicity, C₆₀ was incorporated into living human phagocytes. It was observed that C₆₀ has no influence on the survival of human leukocytes.     

Potentiometric study of poly(l-glutamic acid) in water-dioxane mixtures

The potentiometric behaviour of poly(l-glutamic acid) (PLGA) has been studied in several water-dioxane mixtures and 0.2 M NaCl/dioxane mixtures. The intrinsic ionization constant pK₀ was found to increase with dioxane content and decreasing temperature. This variation of pK₀ with dioxane content can be explained by the variation of the dielectric constant, ? of the solvent. The free energy change ΔF° associated with the helix-coil transition for the uncharged conformers has been determined. At 25°C, the absolute value of ΔF° increases when decreasing the dielectric constant (i.e. when increasing the dioxane content) but the comparison with the experimental results of other authors show that a change in ? is not sufficient to explain the variations of ΔF° in all solvent mixtures. The temperature dependence of ΔF° in different 0.2 M NaCl/dioxane mixtures was determined between 3° and 55°C. The experimental results show that the stabilization of the α helix by dioxane has an entropic origin as it was already found for a 0.1 M KCl/ethanol/PLGA system. In the absence of salt, a sharp change in the variation of ΔF° is observed for the solvent composition at which a solvent induced conformational transition occurs, along with a change in the absolute adsorption of dioxane on the PLGA molecule. The free energy change involved in the adsorption of a molecule of dioxane on a PLGA residue has been evaluated.     

Neuromuscular blocking drugs and heart rate changes after direct nerve stimulation and during classical conditioning in cats.

2 experiments investigated cardiovascular responses to several common neuromuscular blocking compounds. Exp I, employing 16 male cats, assessed ganglionic transmission in sympathetic and parasympathetic systems controlling heart rate and blood pressure after dextrotubocurarine chloride (TC), dimethyl dextrotubocurarine iodide (DTI), succinylcholine chloride (SC), or saline. Cardiovascular responses to sympathetic stimulation were essentially unaffected at drug levels that blocked evoked electromyograms; however, vagally evoked bradycardia and corresponding blood pressure decrease were blocked by TC and reduced by DTI and SC. Exp II compared heart responses of 12 male cats under the same blocking compounds during differential classical aversive conditioning. Differential conditioned responses and unconditioned responses occurred under DTI, less under SC, but not under TC. However, Ss trained under TC and tested under DTI showed differential conditioned responses. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Grafted polymers from poly(4-vinylpyridinium) salts

4-Vinyl pyridine can be added via its vinylic double bond to the quaternary nitrogen atom of poly(4-vinylpyridinium chloride). When this reaction is carried out successively, model grafted polymers with grafts of a constant length with a known number of electric charges, have been obtained. Potentiometric measurements, infra-red and ¹H n.m.r. spectroscopic studies confirm the structure of the polymers.     

Electrochemical behaviour of lead chloride (PbCl2) in dimethylsulphoxide (DMSO)—II. a chronopotentiometric study

In our earlier electrode kinetic studies (chronopotentiometric) of lead chloride (PbCl₂) in dimethylsulfoxide (DMSO), the points in the plot of E, vs log (τ^1/2 ? t^1/2) were linear in the form of a wave. This situation was similar to that observed by Delahay in the chronopotentionmetric reduction of chromate ion (aqueous medium) and thought to be due to a prekinetic step. To verify the presence of a prekinetic step in our case a survey of iτ^1/2vs i for a wider range of lead chloride concentration was started. But a distortion observed in the initial part of the curve (from 4·0 mM PbCl₂) was another point of similarity with that of chromate ion. This led us to consider the polarographic and chronopotentiometric reduction behaviour of CrO^2?₄ in two different electrolytes sodium hydroxide and sodium carbonate. Such considerations justify the presence of a prekinetic step in electrochemical reduction of chromate. Such a prekinetic step, probably the dissociation of PbCl₂, is verified and Kk^1/2₂ values for this coupled chemical reaction are determined according to the transition time expressions of Delahay and Dracka.     

Robust control of a class of non-linear systems and applications to robotics

This paper addresses the problems of designing and analysing a set of stable and robust controls for nonlinear systems whose equations are representative of mechanical systems such as robot manipulators. When applied to robotics, this theoretical analysis proves that most of the control schemes which are used in practice or proposed in the literature, ranging from the simplest PD control to more complex controls such as adaptive controls or controls based on the so-called ‘computed torque method’, are liable to perform equally well if the manipulator is perfectly rigid and ideal sensors are used. Consequently, it appears that the main justification for using elaborate schemes is to avoid the need for including large constant control gains when high performance is demanded. At this stage, the analysis suggests the possibility of using more flexible non-linear control gains as a way of improving all schemes.     

Copper doped zinc oxide Y2BaZnO5: ERS and optical investigation

In copper doped Y₂BaZnO₅ oxides, copper exhibits a distorted square pyramidal coordination which is consistant with the values of g and A tensors obtained from O band ERS spectrum for a sample containing about 1 % Cu. Three values for g and A are observed, g₁ = 2.049₅, g₂ = 2.051₅, g₃ = 2.275, $\text{¦}\text{A}{}_1\text{¦ = 13 10}{}^{\mathrm{?4}}\text{cm}{}^{\mathrm{?1}}$, $\text{¦}\text{A}{}_2\text{¦ = 10 10}{}^{\mathrm{?4}}\text{cm}{}^{\mathrm{?1}}$ and $\text{¦}\text{A}{}_3\text{¦ = 147.5 10}{}^{\mathrm{?4}}\text{cm}{}^{\mathrm{?1}}$. Since $\text{g}{}_1\text{?}\text{g}{}_2$ an approximate C_4v point symmetry can be assumed for copper. The electronic spectrum shows three bands at 11700, 14500 and 20500 cm^?1 which can be assigned to the transitions A₁ → B₁, B₂ → B₁ and E → B₁ respectively. The orbital reduction parameters are calculated and the bonding covalency is discussed.     

Effects of adrenal demedullation on the conditioned emotional response and on the memory improving action of glucose.

Results of previous experiments have demonstrated that posttraining, noncontingent ingestion of sucrose solutions, or injection of glucose solutions improve retention of various learning tasks. In the present experiment, we tested the hypothesis that this effect is due to a glucose-stimulated release of epinephrine from the adrenal medulla by testing the effect of posttraining glucose injections on retention of a conditioned response (CER) in demedullated rats. In a preliminary experiment, demedullated rats were found to be deficient at acquiring the CER, but a similar deficit in sham-operated animals suggested that this was due to the surgical procedure rather than to the absence of the adrenal medulla. When appropriate shock parameters were used, posttraining glucose improved retention of the CER in a manner parallel to the effect of this treatment in normal rats. It was concluded that the memory improving effect of posttraining glucose does not involve an effect of this substance on the adrenal medulla. (PsycINFO Database Record (c) 2010 APA, all rights reserved)