A comparative evaluation of crumb rubber and devulcanized rubber modified binders

One of the most prominent uses of ground tire rubber (GTR) is in rubber-modified asphalt industry. Besides improving performance properties of binders, GTR induces some drawbacks like weak storage stability and inferior low temperature (LT) performance. This study sought to rectify these shortcomings through using devulcanized rubber (DVR) in place of common GTR. Binder performance grading, multiple stress creep and recovery, and storage stability tests were conducted. More resistance against traffic loads at high temperatures was observed as DVR's advantages over GTR, while its weaker LT characteristics and lower storage stability can prevent it from being a viable alternative.     

Unfolding the frequency spectrum for undersampled wideband data

In this letter, we discuss the problem of unfolding the frequency spectrum for undersampled wideband data. The problem is of relevance to state-of-the-art radio frequency measurement systems, which capture repetitive waveform based on a sampling rate that violates the Nyquist constraint. The problem is presented in a compact form by the inclusion of a complex operator called the CN operator. The ease-of-use problem formulation eliminates the ambiguity caused by folded frequency spectra, in particular those with lines standing on multiples of the Nyquist frequency that are captured with erroneous amplitude and phase values.     

Computational platform for the integrated life-cycle management of highway bridges

Throughout their service life, highway bridges are subject to progressive deterioration in performance; an issue that may render the use of these facilities unsafe at some point in time. Over the last few decades, there has been successful research towards developing procedures for establishing the various vital elements required in the life-cycle management of civil infrastructure. It is noted, however, that frameworks for integrating these elements together are lacking. The objective of this paper is to present an integrated framework for the life-cycle management of highway bridges in the form of a detailed computational platform. The elements integrated into the framework include the advanced assessment of life-cycle performance, analysis of system and component performance interaction, advanced maintenance optimization, and updating the life-cycle performance by information obtained from structural health monitoring and controlled testing.     

(PEG) x NH4ClO4: a new polymeric fast proton conductor

A new polymer electrolyte (PEG) _x NH₄ClO₄(x = 5, 10, 15, 20) has been prepared that shows protonic conduction. The room temperature conductivities are of the order of 10⁻⁷S/cm, and increase with decrease in salt concentration. NMR line width studies indicate fairly low glass transition temperatures of the polymer salt complexes. Paper presented at the poster session of MRSI AGM VI. Kharagpur, 1995     

THE HYDROCARBON POTENTIAL OF LEBANON: NEW INSIGHTS FROM REGIONAL CORRELATIONS AND STUDIES OF JURASSIC DOLOMITIZATION

This paper presents an updated review of the petroleum prospects of Lebanon. We briefly describe the known hydrocarbon shows in Lebanon and compare them with adjacent countries, leading to the construction of a model for hydrocarbon migration which takes into account regional facies and reservoir correlations. The oldest exposed rocks in Lebanon are the Jurassic carbonates of the Kesrouane Formation (over 1,000m thick). This formation can be divided into a basal unit dominated by seepage‐reflux stratabound dolostones (the Chouane Member,) and an overlying limestone‐prone unit (the Nahr Ibrahim Member). A two‐stage dolomitisation model for the Jurassic carbonates in Lebanon has recently been proposed by the authors. According to this model, second‐stage Late Jurassic hydrothermal dolomitisation is believed to have occurred as a result of the circulation of mixed dolomitising fluids along faults. Hence, the resulting dolostones are fault‐controlled and strata‐discordant, and may occur at any level within the Kesrouane Formation, locally redolomitising the Chouane Member dolostones and replacing the Nahr Ibrahim Member limestones. In this paper, we discuss the implications of diagenesis (especially dolomitisation) on the petroleum prospects of the Kesrouane Formation in Lebanon. The hydrothermal fault‐related dolostones possess porosities of up to 20%, which result from intercrystalline and mouldic porosity enhancement. Porosities in the stratabound reflux dolostones (Early Jurassic) and limestones are much lower. The fact that most of the Jurassic system in onshore Lebanon was affected by meteoric diagenesis during the Late Jurassic ‐ Early Cretaceous and the Cenozoic may downgrade hydrocarbon prospectivity. However, offshore areas far from the meteoric realm may have been less (or not at all) affected by meteoric invasion. If effective seals are present there, these areas may host promising Jurassic reservoir units. We also review the prospectivity of unexposed Triassic potential reservoir units in onshore Lebanon (e. g. the “Qartaba” structure). By analogy with the Syrian portion of the Palmyride Basin, Triassic strata here may include both reservoir units and evaporite seals.     

Dimensions of the “people problem” in energy research and “the” factual basis of dispersed energy futures

Those of us advocating adaptive behavior in times of scarcity and change of resources need to be more aware of the roles we are playing and of the ideas that influence our actions. Some important dimensions of the “people problem” often appear in binary opposition: institutional constraints vs individual freedom, credible vs non-credible, tangible vs abstract, restricted vs global time perspective, specialist vs generalist, voluntary vs involuntary, and progress vs decline or status quo. Several of these dimensions were central to our understanding of two transitional mechanisms in California: the Residential Building Code and the exploration of the potential of dispersed electric generators. The “people problems” of energy reach beyond the technical-science problems, and beyond educating the little people in the value of efficiency, conservation, and the impending exhaustion of fossil fuels. Indeed, they are central to any compilation of the factual basis of dispersed energy futures. Experts and decision-makers need to look within themselves for an improved understanding of what constitutes “the” energy problem and, indeed, what constitutes “the” factual basis for energy planning.     

Lesions of the lateral parabrachial nucleus block the aversive motivational effects of both morphine and morphine withdrawal but spare morphine's discrimination properties.

This study examined if the aversive properties of morphine, the aversive properties of morphine withdrawal, and the discriminative properties of morphine are mediated by common neurobiological substrates. Lesions of the lateral parabrachial nucleus, which blocked the aversive properties of morphine in the conditioned taste aversion paradigm, also blocked the acquisition of conditioned place aversions to environments paired with the aversive properties of morphine withdrawal in morphine-dependent rats. When morphine and saline were used as cues in a discrimination task, however, both sham-operated and lesioned rats were able to solve the task. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Determinants of dietary intake in a sample of white and Mexican-American children

Using a modified method consisting of chromatography on phenyl-Sepharose, Q-Sepharose, and hydroxyapatite, we isolated a highly purified heat shock protein with molecular weight 90 kD (Hsp90) from rabbit liver. The isolated protein was recognized on immunoblot by commercially available monoclonal anti-Hsp90 antibodies. The chromatographic properties, interaction with actin and calmodulin, phosphorylation in the presence of Mg-ATP, and one-dimensional peptide maps of rabbit liver Hsp90 are similar to the corresponding properties of Hsp90 isolated from other sources. In the presence of soluble carbodiimide and N-hydroxysuccinimide, rabbit liver Hsp90 can be cross-linked with calmodulin, troponin C, troponin I, and calponin. The data obtained indicate that Hsp90 may participate in the assembly of regulatory proteins of the actin filament.