Sulphur compounds in the kerosine boiling range of middle east distillates Occurrence of a bicyclic thiophene and a thienyl sulphide

A bicyclic thiophene, 1,4,4-trimethyl-4,5,6,7-tetrahydroisothianaphthene, and a thienyl sulphide, methyl 3, 4, 5-trimethyl-2-thienyl sulphide, have been isolated from a concentrate of sulphur compounds obtained in the refining of a Middle East kerosine. The structures of these compounds have been established.     

Isotherms of the rare gas solids

The experimental data of Anderson, Fugate and Swenson for the rare gas solids are recast in a dimensionless form which exhibits the close approach to the Lennard-Jones form except at the highest temperatures, and also in a form derived from the theory of finite elasticity. The latter is particularly useful when ultrasonic data furnish initial values of the modulus of compression. It also has the merit that no a priori assumptions concerning interatomic potentials are implicit, except that the strain-energy may be expanded in powers of the strain.     

Transition to Chaos in the Floating Half Zone Convection

The transition process from steady convection to chaos is experimentally studied in thermocapillary convections of floating half zone. The onset of temperature oscillations in the liquid bridge of floating half zone and further transitions of the temporal convective behaviour are detected by measuring the temperature in the liquid bridge. The fast Fourier transform reveals the frequency and amplitude characteristics of the flow transition. The experimental results indicate the existence of a sequence of period-doubling bifurcations that culminate in chaos. The measured Feigenbaum numbers are δ2 =4.69 and δ4 = 4.6, which are comparable with the theoretical asymptotic value δ=4.669.     

Optical resolution of tricarbonyl(1-carboxycyclohexa-1,3-diene) iron and the absolute configuration of the products

Resolution of the acid ($\text{1}$) (shown as the (+)-isomer) into its optically pure (+) and (?) isomers and reduction of the CO₂H yields the 2-Me derivative ($\text{2}$) (shown as the (?)-isomer). The absolute configuration of ($\text{2}$) is defined by conversion of the salt ($\text{3}$) of known configuration into ($\text{2}$) and ($\text{4}$). This is the first resolution leading to preparation of pure complexes of known absolute configuration.     

A new mild radical route to 3-substituted maleimides using organoboroles

A new, mild, radical route for the synthesis of 3-substituted maleimides has been developed. This new method incorporates alkene hydroboration, conjugate addition-aminoxylation and TEMPO-H elimination in a one-pot procedure, using cheap, readily available starting materials. A variety of 3-substituted maleimides have been prepared in good to excellent yield.     

Directional limits on persistent gravitational waves using LIGO S5 science data

The gravitational-wave (GW) sky may include nearby pointlike sources as well as stochastic backgrounds. We perform two directional searches for persistent GWs using data from the LIGO S5 science run: one optimized for pointlike sources and one for arbitrary extended sources. Finding no evidence to support the detection of GWs, we present 90% confidence level (C.L.) upper-limit maps of GW strain power with typical values between 2-20×10(-50) strain(2)?Hz(-1) and 5-35×10(-49) strain(2)?Hz(-1)?sr(-1) for pointlike and extended sources, respectively. The latter result is the first of its kind. We also set 90% C.L. limits on the narrow-band root-mean-square GW strain from interesting targets including Sco X-1, SN 1987A and the Galactic center as low as ≈7×10(-25) in the most sensitive frequency range near 160 Hz.