Mixed micelles of benzyldimethyltetradecylammonium chloride with tetradecyltrimethylammonium and tetradecyltriphenylphosphonium bromides: a head group contribution

Mixed micelle formation by tetradecyltrimethylammonium (TTAB) and tetradecyltriphenylphosphonium bromides (TTPB) with benzyldimethyltetradecylammonium chloride (BTDACl) was studied with the help of conductivity and Kraft point measurements. The BTDACl + TTAB mixtures showed synergistic interactions whereas those of BTDACl + TTPB indicated weak antagonistic behavior. From Kraft temperature measurements, the enthalpy of fusion (H(1)(0)) from solid hydrated BTDACl to the liquid state in the presence of TTAB or TTPB was computed. It was found that DeltaH(1)(0) was much more positive for BTDACl + TTPB than for BTDACl + TTAB mixtures.     

A FAST pattern matching algorithm

The advent of digital computers has made the routine use of pattern-matching possible in various applications. This has also stimulated the development of many algorithms. In this paper, we propose a new algorithm that offers improved performance compared to those reported in the literature so far. The new algorithm has been evolved after analyzing the well-known algorithms such as Boyer-Moore, Quick-search, Raita, and Horspool. The overall performance of the proposed algorithm has been improved using the shift provided by the Quick-search bad-character and by defining a fixed order of comparison. These result in the reduction of the character comparison effort at each attempt. The best- and the worst- case time complexities are also presented in this paper. Most importantly, the proposed method has been compared with the other widely used algorithms. It is interesting to note that the new algorithm works consistently better for any alphabet size.     

Voter model on heterogeneous graphs

We study the voter model on heterogeneous graphs. We exploit the nonconservation of the magnetization to characterize how consensus is reached. For a network of N nodes with an arbitrary but uncorrelated degree distribution, the mean time to reach consensus T(N) scales as Nmu(2)1/mu(2), where mu(k) is the kth moment of the degree distribution. For a power-law degree distribution n(k) approximately k(-nu), T(N) thus scales as N for nu > 3, as N/ln(N for nu = 3, as N((2nu-4)/(nu-1)) for 2 < nu < 3, as (lnN)2 for nu = 2, and as omicron(1) for nu < 2. These results agree with simulation data for networks with both uncorrelated and correlated node degrees.     

General features ofK + d interactions at 70 GeV/c

We have studied 70 GeV/cK ⁺ d interactions from about 10 K events. The inelastic cross-section for three or more prongs is found to be (28.9±0.4) mb. From odd-and even-prong topologies we have extracted topological break-up ofK ⁺ n interactions by taking into account spectator corrections, rescattering effects and Glauber screening. The rescattering fraction is found to be 0.06±0.01 which is substantially different from pion and proton interactions. Combining ourK ⁺ n data with other existing π^± n andp ^±n we find〈n _ch 〉 ^ph ?〈n _ch 〉 ^hn =0.33±0.04 andD/〈n _ch 〉=0.529±0.003.     

Quantification of transients using empirical orthogonal functions

The method of empirical orthogonal functions (EOFs) is used to analyse spatio-temporal data obtained from simulations of heterogeneous catalysis. It is found that EOFs are well suited for the quantitative determination of transients in the data. The effectivity of the technique is demonstrated using synthetical data with an analytically known transient component.     

Structure and vibrational properties of carbon tubules

The structure of multilayered carbon tubules has been investigated by electron microscopy and X-ray diffraction. The structure of tubules is characterized by disorder in the stacking of cylindrical graphene sheets. Raman scattering measurements have been carried out in tubules and compared with graphite. The observed features in the Raman spectra in tubules can be understood in terms of the influence of disorder. The additional Raman modes predicted for single layer carbon tubules have not been observed.     

Thermoreflectance of IV–VI compounds

We have measured thermoreflectance spectra of epitaxial PbS, PbSe, PbTe, and SnTe films from 0.7 to 5.6 eV, at room temperature and 77 K. Fine structures associated with the usual reflectivity peaks are observed, most of which agree in spectral position with electric field and wavelength modulation results. Δε_r and Δε_i have been obtained through a Kramers-Kronig analysis of our Δ R/R spectra. In the absence of experimental symmetry information, tentative assignments are made based on (1) comparison of temperature coefficients with theoretical deformation potentials, (2) comparison of δε curves with theoretical lineshapes, and (3) matching the structures with existing band structure calculations and related information.