In this work we report the chain length dependent behavior of the nonamphiphilic supramolecular building blocks based on the host-guest inclusion complexes of alkanes and β-cyclodextrins (β-CD). (1)H NMR, ESI-MS, and SAXS measurements verified that upon increasing the chain length of alkanes, the building blocks for vesicle formation changed from channel type 2alkane@2β-CD via channel type alka...

The pentacyclic triterpene 17 beta(H),21 beta(H)-hop-22(29)-ene (diploptene) occurs in sediments throughout the Columbia River drainage basin and off the southern coast of Washington state in concentrations comparable to long-chain plantwax n-alkanes. The same relationship is evident for diploptene and long-chain n-alkanes in soils from the Willamette Valley. Microorganisms indigenous to soil...

Short-chain chlorinated paraffins (SCCPs) are highly complex technical mixtures of polychlorinated n-alkanes with carbon-chain lengths from C10-C13 and chlorine content between 49 and 70%. They are produced by chlorination of n-alkanes and do not occur naturally. Because of their physical properties (viscosity, flame resistance) they are used in many different applications, such as lubricant ad...

A new strain of Prototheca zopfii Krüger was grown on acetate or on pure n-alkanes. A maximum acetate-supported exponential growth of 12 divisions day occurred at pH 5 and 30 degrees C. At 25 degrees C, growth on n-alkanes was almost as fast, but no growth occurred at 30 degrees C. After 4 days at 25 degrees C, 34 to 45% of the n-alkanes had been removed, whereas at 21 degrees C and slower grow...

A highly-integrated experimental system for plasma decomposition of fuels was built. Experiments were conducted and confirmed that macromolecular chain hydrocarbons were cracked by large-gap dielectric barrier discharge under the excitation of a microsecond-pulse power supply. Alkanes and olefins with a C atom number smaller than 10 as well as hydrogen were found in the cracked products of n-de...

the aim of this research was to optimize bioremediation of seawater samples spiked with 1000 mg/l crude oil for removal of n-alkanes (c12h26 to c34h70). bioaugmentation experiments were performed at laboratory scale: each bioreactor contained 250 ml dispersed crude-oil-contaminated seawater, indigenous acclimatized microorganism and nitrogen and phosphorus at concentrations based on central com...

One of the difficulties in reporting accurate radiocarbon results from compoundspecific radiocarbon analysis (CSRA) is the lack of suitable process standard materials to correct for the amount and C content of carbon added during extensive sample processing. We evaluated the use of n-alkanes extracted from modern grass material (1.224 ±0.006 fraction modern) as process standards for CSRA. The n...

Environmental microbes utilize four degradation pathways for the oxidation of n-alkanes. Although the enzymes degrading n-alkanes in different microbes may vary, enzymes functioning in the first step in the aerobic degradation of alkanes all belong to the alkane hydroxylases. Alkane hydroxylases are a class of enzymes that insert oxygen atoms derived from molecular oxygen into different sites o...