Has Bell's inequality a general meaning for hidden-variable theories?

We analyze the proof given by J. S. Bell of an inequality between mean values of measurement results which, according to him, would be characteristic of any local hidden-parameter theory. It is shown that Bell's proof is based upon a hypothesis already contained in von Neumann's famous theorem: It consists in the admission that hidden values of parameters must obey the same statistical laws as observed values. This hypothesis contradicts in advance well-known and certainly correct statistical relations in measurement results: One must therefore reject the type of theory considered by Bell, and his inequality has no general meaning.     

BaSnF4 fast ion conductor: Variations versus the method of preparation and anomalous temperature variation of the quadrupole splitting

A new method of preparation of high performance fluoride ion conductor, BaSnF₄, by water leaching of newly discovered barium tin(II) chloride fluorides, has been designed, and the materials have been studied and compared to the solid prepared by the usual dry method. The unit-cell parameters and crystallite dimensions were found to vary with the method of preparation. In addition, the crystallite dimensions were found to be highly anisotropic for the samples obtained by the wet method. The Mössbauer spectrum is made of a large tin(II) quadrupole doublet, and a broad tin(IV) oxide peak due to surface oxidation. The tin(II) spectrum is in agreement with covalently bonded tin(II) having a strongly stereoactive lone pair. An unusually high dependence of the quadrupole splitting at low temperatures was observed (5.8 times larger than for α-SnF₂).     

Understanding the importance of the viscosity contrast between the sample solvent plug and the mobile phase and its potential consequence in two-dimensional high-performance liquid chromatography

The effect of solvent viscosity mismatch on elution performance in reversed-phase HPLC was studied using moment analysis. Two conditions were tested: (1) the mobile phase viscosity was less than the injection plug viscosity, and (2) the mobile phase viscosity was greater than the injection plug viscosity. Under the first condition, retention time and elution performance decreased as the viscosity contrast between the mobile phase and injection plug increased. The effect on performance was more marked as the injection volume increased. A decrease in performance of 12% for compounds with retention factors up to 2.8 was apparent even when the viscosity contrast was only 0.165 cP. In the second set of conditions, elution performance was actually observed to increase, by as much as 25% for a 40 μL injection, as the viscosity contrast between the mobile phase and the solute plug increased. No change in the retention factor was observed. This behaviour was attributed to the shape of an injection plug as it enters into the column, whereby a low viscosity plug permeates away from the wall when the column contains a higher viscosity mobile phase, and vice a versa for a high viscosity plug entering a low viscosity mobile phase. At no stage was either a band splitting or shoulders observed with viscosity contrasts up to 1.283 cP, as could have been expected.     

High peak capacity separations of peptides in reversed-phase gradient elution liquid chromatography on columns packed with porous shell particles

The performance of 5 and 15 cm long columns packed with shell particles (Halo, AMT) is compared in gradient elution separations of the tryptic digests of myoglobin and bovine serum albumin. The influences of the temperature and the mobile phase flow rate on the column efficiency for two peptides are discussed. The influences of this flow rate, of the temperature, and of the gradient slopes on the peak capacities are also considered. Peak capacities in excess of 400 were achieved in 6h with the longer column. Peak capacities of 200 could be achieved in 30 min with the shorter column.     

Investigation of the thermal lens effect in water-ethanol mixtures: composition dependence of the refractive index gradient, the enhancement factor and the Soret effect.

The thermal lens effect produced in binary mixtures of water and ethanol has been investigated. It is shown that the sensitivity of the thermal lens method upon the addition of ethanol in water varies as the temperature-dependent refractive index gradient to thermal conductivity ratio of the mixture. The dependence of k and dn/dT upon the ethanol volume fraction follows a second-order and fourth-order polynomial, respectively, and cannot be precisely predicted using the additive rule. Moreover, depending on the experimental conditions and the mixture composition, the temperature gradient produced subsequently to relaxation of the excited species induces mutual migration of the solvent molecules and the formation of a concentration gradient in the irradiated area. This effect, known as the Soret effect, can locally change the thermo-optical properties of the solution and produce an additional signal, especially when steady-state experiments are done. This may result in errors as large as 20% when quantitative informations have to be derived from experimental data.     

Repeatability and reproducibility of retention data and band profiles on six batches of monolithic columns

Chromatographic data were acquired for eight different mixtures, under five different sets of experimental conditions, for a total of 30 neutral, acidic and basic test compounds, on a series of six Chromolith Performance columns from Merck. These columns are made of a C₁₈ chemically bonded silica monolith. Each column belonged to a different production batch, so the data reported here characterize their batch-to-batch reproducibility. The parameters studied in this work were the retention times, the retention and separation factors, the hydrophobic and the steric selectivities, the column efficiencies, and the tailing factors for all 30 compounds.     

6,6-dimethyl-1-oxa-spiro[2.5]octane. Conformational equilibrium in the gas phase as studied by microwave spectroscopy and molecular mechanics calculations

The gas-phase molecular structure of 6,6-dimethyl-1-oxa-spiro[2.5]octane has been investigated by joint analysis of the microwave spectrum and molecular mechanics calculations. Both experimental and theoretical data concur showing the presence of two stable conformational isomers having a chair cyclohexane ring. A set of structural parameters which reproduce the ground state rotational constants has been derived. The influence of 1,4 disubstitution is discussed in terms of deformations of the cyclohexane ring.     

Crystal structures and physico-chemical properties of Zn(II) and Co(II) tetraaqua(3-nitro-4-hydroxybenzoato) complexes: Their anticonvulsant activities as well as related (5-nitrosalicylato)–metal complexes

Purposes of these studies were to synthesize Zn(II) and Co(II) complexes of 3-nitro-4-hydroxybenzoic acid, determine their structures through X-ray crystallography, and obtain their anticonvulsant activities. Thermogravimetric, differential scanning calorimetry, impedance of aqueous solutions and magnetic properties analyses were also determined. Anticonvulsant and related activities of these complexes as well as Zn(II), Co(II), Ni(II) and Mg(II) (5-nitrosalicylato) complexes were determined by the National Institutes of Health, Antiepileptic Development Program. Results of these analyses are presented to document unique bonding features and physical properties of these compounds and their anticonvulsant activities. It is concluded that these compounds have chemical and physical properties that can be used to account for their anticonvulsant activities.