Studies on models synthesized by stereochemically controlled routes show that the central triene chromophore in the common cis isomer of phytoene has the irans,cis,trans configuration, and that the phytoene from Flavobacterium dehydrogenans consists mainly of the all-trans isomer. Capsorubin, with the natural configuration at all four chiral centres, has been synthesized from (+)-camphor. Sever...

Alkyldifluorophosphites, ROPF2 (R = ^-substituted benzyl group, neopentyl, 1-adamantyl) have been obtained by a new method, involving reaction of the appropriate alkyl trimethylsilylether, ROSiMe3 with chlorodifluorophosphine, PF2C1. Reactions of these difluorophosphites with platinum(II) complexes of the type [LaPtCla] (L = PEt3, PPI13) led to products such as irans-[L2PtCl(POF2)] and {[p-XC6H...

Empirical data and statistical models are used to answer the question of where the new highway routes are most likely to be located. High-quality land-use, population distribution and highway network GIS data for the Twin Cities Metropolitan Area from 1958 to 1990 are developed for this study. The highway system is classified into three levels, Interstate highways, divided highways, and seconda...

Operational speed is an index that represents drivers’ speeding behaviors and shows the comfort and safety levels they experience. Many models had been proposed to predict operational speed in tangent and curve segments of highways. Most of these works had used geometric, with few of them conducted using roadside variables to predict operational speed. Also, the operational speed study in multi...

Highways are an essential component of our society because they are critical to quality of life and to local and national economies. Under good conditions, highways provide a safe and efficient route for people and goods to reach their destinations. However, as a direct consequence of their use, traffic congestion is ever-increasing, undermining the ability of highways to adequately provide an ...

Through utilizing US state-level data at annual frequency from 1976 to 2008, this paper documents a causal effect of infrastructure investments, specifically public spending on highways, on income inequality. The number of seats in the US House of Representatives Committee On Appropriations serves as a valid instrument to identify quasi-random variations in state-level spending on highways. Whe...