Revised Robertson's test theory of special relativity: Space-time structure and dynamics

The experimental testing of the Lorentz transformations is based on a family of sets of coordinate transformations that do not comply in general with the principle of equivalence of the inertial frames. The Lorentz and Galilean sets of transformations are the only member sets of the family that satisfy this principle. In the neighborhood of regular points of space-time, all members in the family are assumed to comply with local homogeneity of space-time and isotropy of space in at least one free-falling elevator, to be denoted as Robertson'sab initio rest frame [H. P. Robertson,Rev. Mod. Phys. 21, 378 (1949)].Without any further assumptions, it is shown that Robertson's rest frame becomes a preferred frame for all member sets of the Robertson family except for, again, Galilean and Einstein's relativities. If one now assumes the validity of Maxwell-Lorentz electrodynamics in the preferred frame, a different electrodynamics spontaneously emerges for each set of transformations. The flat space-time of relativity retains its relevance, which permits an obvious generalization, in a Robertson context, of Dirac's theory of the electron and Einstein's gravitation. The family of theories thus obtained constitutes a covering theory of relativistic physics.A technique is developed to move back and forth between Einstein's relativity and the different members of the family of theories. It permits great simplifications in the analysis of relativistic experiments with relevant Robertson's subfamilies. It is shown how to adapt the Clifford algebra version of standard physics for use with the covering theory and, in particular, with the covering Dirac theory.Part of this work was done at the Department of Physics, Utah State University, Logan, Utah 84322.     

Determination of DNA structure in solution: enzymatic deuteration of the ribose 2' carbon

An enzymatic solution to the problem of obtaining 13C/15N-labeled nucleotides that are deuterated uniquely at the H2' ' position within the ribose ring is presented. Selective deuteration occurs with an overall yield of >80%. The deuteron at the H2' ' position allows measurement of the scalar and residual dipolar couplings for the bond vectors attached to the C2' carbon of each ribose sugar. These data allow the accurate determination of sugar conformation. Interesting DNA double helices of 2-3 turns are now within the reach of solution NMR spectroscopy. As an example, these labeled nucleotides are incorporated uniquely at positions 6-14 in a 20-bp DNA sequence containing the adenovirus major late promoter.     

Volatile phase profiling of mainstream smoke by glass capillary gas-chromatographic techniques

A heated injection system for a microprocessor-controlled GC has been developed for the (GC)² analysis of the volatile phase of whole smoke of a cigarette. Effects of injection port temperature and the presence of a Cambridge filter pad are demonstrated. Chromatograms are shown for smoke samples with and without a Cambridge Filter with the sample valve oven at 25°, 165° and 205°C. The use of a flame ionization and a nitrogen-phosphorous detector is illustrated.     

Reactions of metal carbonyl cluster complexes with multidentate phosphine ligands; reactions with bis(diphenylphosphino)methane

Reactions of Rh₆(CO)₁₆ with bis(diphenylphosphino)methane (dppm) gave Rh₆(CO)₁₄(dppm), Rh₆(CO)₁₂(dppm)₂, or Rh₆(CO)₁₀(dppm)₃, depending upon the reaction conditions. Rh₄(CO)₁₀(dppm) may be obtained from the reaction of Rh₄(CO)₁₂ with dppm, but this derivative rapidly decomposes in solution to give Rh₄(CO)₈(dppm)₂, Rh₆(CO)₁₄(dppm), and Rh₆(CO)₁₂(dppm)₂. Ir₄(CO)₁₀(dppm) and Ir₄(CO)₈(dppm)₂ have also been prepared, and their structures are discussed on the basis of infrared and ³¹P NMR spectroscopic data.     

Time-resolved fluorescence spectra using time-correlated photon counting: Picosecond fluorescence in aqueous solutions of Cr(III) complexes at room temperature

A new procedure for measuring time-resolved emission spectra has been implemented. This technique has subnanosecond time resolution combined with the sensitivity and dynamic range needed to cope with extremely weak luminescence. Using this method the emissions of Cr(NH₃)₂ (NCS)₄^? and Cr(NCS)₆^3- in aqueous solution at room temperature have each been analyzed into two components. The fast component has a broad spectrum and is assigned to prompt fluorescence with lifetime below 100 ps. The slow component is dominated by phosphorescence but may include some delayed fluorescence. The phosphorescence lifetime is 5.5 ± 0.5 ns in Cr(NH₃)₂ (NCS)₄^? and 1.65 ± 0.1 ns in Cr(NCS)₆^3-. Order of magnitude estimates have been derived for other photophysical parameters.     

PHOTOSENSITIZATION BY ANTIMALARIAL DRUGS

Abstract The antimalarial drugs, chloroquine, hydroxychloroquine, quinine, quinacrine, amodiaquine and primaquine and the local anaesthetic, dibucaine, were tested for in vitro photosensitizing capability by irradiation with 365 nm UV light in aqueous solutions. The ability of these compounds to photosensitize the oxidation of 2,5-dimethylfuran, histidine, tryptophan or xanthine, and to initiate the free radical polymerization of acrylamide was examined in the pH range 2-12. Chloroquine and hydroxychloroquine show maximal photooxidative behaviour when in the monocation form at pH 9, in contrast to quinine which is extremely efficient as the dication below pH 4. This pattern appears to relate to the fluorescence yield as a function of pH. Chloroquine in the monocation or neutral form was found to undergo dechlorination upon irradiation, and this correlates directly with its ability to initiate photo-polymerization of acrylamide. Quinine also gives rise to small polymerization rates, attributed to photo-ionization in the quinoline ring, yielding a cation radical. Amodiaquine, primaquine and quinacrine do not have significant photochemical activity in aqueous solution. Dibucaine exhibits a strong photosensitizing capability at low pH, similar to quinine.     

Adsorption of water molecules in slit pores

We report molecular dynamics (MD) simulations on the adsorption of water in attractive and repulsive slit pores, where the slit and a bulk region are in contact with each other. Water structure, surface force and adsorption behavior are investigated as a function of the overall density in the bulk region. The gas–liquid transition in both types of pores occurs at similar densities of the bulk region.     

N-butyl-,N-iso-butyl-andN-sec-butyl-2-picolinamineN-oxide complexes derived from copper(II) salts of polyatomic anions

Summary N-butyl-,N-iso-butyl- andN-sec-butyl-2-picolinamineN- oxide complexes have been prepared from copper(II) perchlorate, tetrafluoroborate and nitrate. Violet solids were isolated from the first two salts while complexes isolated from the nitrate salt were blue green or blue. The ligands coordinatevia both theN-oxide oxygen and the amine nitrogen to give bis (ligand) complexes and only in the case of the nitrate solids is there interaction between the copper(II) centre and the polyatomic anion. Resolution of the g feature in the powder spectra of several of these complexes results from the bulkiness of the butyl groups and therefore dilution of the copper(II) centers. In comparison to the previously studied 2 picolinamineN-oxides with lower alkyl substituents, the complexes have stronger in-plane bonding by the ligands.NATO Fellow on leave from Istanbul Medical Faculty, Istanbul University.     

Superexchange in copper(II) Dimers. 3. Synthesis and characterization of binuclear adducts of copper(II) halides with some α,β-dione dioximes

Copper(II) halides, CuX₂ (X = Br^?, Cl^?), have been combined in non-aqueous medium with various α,-β-dione dioxime (α,β-dodoH) ligands to produce new 1:1 adducts, the di-μ-halo-bis[halo(α,β-dodoH)copper(II)] dimers. These are: Di-μ-bromo-bis[bromo(ethanedialdioxime)copper(II)]; di-μ-bromo-bis[bromo(diphenylethanedione dioxime)copper(II)]; di-μ-bromo-bis-[bromo(9,10phenanthrenedione dioxime)copper(II)]; di-μ-chloro-bis-[chloro(9,10-phenanthrenedione dioxime)copper(II)]. The materials were characterized by conventional methods. The results clearly indicate that the compounds crystallize in discrete dimers, quite consistent with the results of closely related dimers studied earlier.     

On resolvable Golomb rulers,symmetric configurations and progressive dinner parties

Journal of Algebraic Combinatorics - We define a new type of Golomb ruler, which we term a resolvable Golomb ruler. These are Golomb rulers that satisfy an additional “resolvability”...