Pyrophosphate Selective Recognition in Aqueous Solution Based on Fluorescence Enhancement of a New Aluminium Complex

A novel and simple fluorescence enhancement method for selective pyrophosphate(PPi) sensing was proposed based on a 1:1 metal complex formation between bis(8-hydroxy quinoline-5-solphonat) chloride aluminum(III) (Al(QS)₂Cl), (L) and PPi in aqueous solution. The linear response range covers a concentration range of 1.6 × 10⁻⁷ to 1.0 × 10⁻⁵ mol/L of PPi and the detection limit of 2.3 × 10⁻⁸ mol/L. The association constant of L-PPi complex was calculated 2.6 × 10⁵ L/mol. L was found to show selectively and sensitively fluorescence enhancement toward PPi over than I₃^-, NO₃^-, CN⁻, CO₃²⁻, Br⁻, Cl⁻, F⁻, H₂PO4⁻ and SO₄²⁻, which was attributed to higher stability of inorganic complex between pyrophosphate and L.     

T Violation and the Unidirectionality of Time

An increasing number of experiments at the Belle, BNL, CERN, DAΦNE and SLAC accelerators are confirming the violation of time reversal invariance (T). The violation signifies a fundamental asymmetry between the past and future and calls for a major shift in the way we think about time. Here we show that processes which violate T symmetry induce destructive interference between different paths that the universe can take through time. The interference eliminates all paths except for two that represent continuously forwards and continuously backwards time evolution. Evidence from the accelerator experiments indicates which path the universe is effectively following. This work may provide fresh insight into the long-standing problem of modeling the dynamics of T violation processes. It suggests that T violation has previously unknown, large-scale physical effects and that these effects underlie the origin of the unidirectionality of time. It may have implications for the Wheeler-DeWitt equation of canonical quantum gravity. Finally it provides a view of the quantum nature of time itself.     

Annealing study of two-dimensional patterned Ge nanostructures via nanosphere lithography

Experimental studies on patterning hexagonal Ge nanostructures have been conducted on Si substrates through deposition of Ge with colloidal particles as a mask. The deposited Ge thin film possesses, according to the X-ray diffraction measurements, in plane texture, being epitaxial and aligned with the (111) Si substrate. The size distribution of the patterned Ge nanostructures is narrow, as indicated by the atomic force microscopy and scanning electron microscopy measurements. We have obtained Ge nanostructures with lateral dimension of 490 nm (height 12 nm), 200 nm (height 6 nm) and 82 nm (height 6 nm) by using different sizes of polystyrene spheres. We have performed in depth studies of the Ge nanostructures’ behavior due to thermal and rapid thermal post-annealing processes. FT micro-Raman spectroscopy shows that there is no Si intermixing during the annealing process. In order to quantify the changes in the height and lateral dimension, we have performed atomic force microscopy and white light interferometry analysis. The changes in shape and the decrease in the area of a cross-section of Ge nanostructure will be discussed in respect to similar results shown in the literature for Ge thin films during the annealing process.     

Enhanced reactivity of nanoscale iron particles through a vacuum annealing process

A reactivity study was undertaken to compare and assess the rate of dechlorination of chlorinated aliphatic hydrocarbons (CAHs) by annealed and non-annealed nanoscale iron particles. The current study aims to resolve the uncertainties in recently published work studying the effect of the annealing process on the reduction capability of nanoscale Fe particles. Comparison of the normalized rate constants (m²/h/L) obtained for dechlorination reactions of trichloroethene (TCE) and cis-1,2-dichloroethene (cis-1,2-DCE) indicated that annealing nanoscale Fe particles increases their reactivity ~30-fold. An electron transfer reaction mechanism for both types of nanoscale particles was found to be responsible for CAH dechlorination, rather than a reduction reaction by activated H₂ on the particle surface (i.e., hydrogenation, hydrogenolysis). Surface analysis of the particulate material using X-ray diffraction (XRD) and transmission electron microscopy (TEM) together with surface area measurement by Brunauer, Emmett, Teller (BET) indicate that the vacuum annealing process decreases the surface area and increases crystallinity. BET surface area analysis recorded a decrease in nanoscale Fe particle surface area from 19.0 to 4.8 m²/g and crystallite dimensions inside the particle increased from 8.7 to 18.2 nm as a result of annealing.     

Damage spreading on networks: Clustering effects

The damage spreading of the Ising model on three kinds of networks is studied with Glauber dynamics. One of the networks is generated by evolving the hexagonal lattice with the star-triangle transformation. Another kind of network is constructed by connecting the midpoints of the edges of the topological hexagonal lattice. With the evolution of these structures, damage spreading transition temperature increases and a general explanation for this phenomenon is presented from the view of the network. The relationship between the transition temperature and the network measure-clustering coefficient is set up and it is shown that the increase of damage spreading transition temperature is the result of more and more clustering of the network. We construct the third kind of network-random graphs with Poisson degree distributions by changing the average degree of the network. We show that the increase in the average degree is equivalent to the clustering of nodes and this leads to the increase in damage spreading transition temperature.      

Zero Modes’ Fusion Ring and Braid Group Representations for the Extended Chiral <Emphasis Type="Italic">su</Emphasis>(2) WZNW Model

A zero modes’ Fock space is constructed for the extended chiral WZNW model. It gives room to a realization of the fusion ring of representations of the restricted quantum universal enveloping algebra at an even root of unity, and of its infinite dimensional extension by the Lusztig operators We provide a streamlined derivation of the characteristic equation for the Casimir invariant from the defining relations of A central result is the characterization of the Grothendieck ring of both and in Theorem 3.1. The properties of the fusion ring in are related to the braiding properties of correlation functions of primary fields of the conformal current algebra model.      

Horizon-less Spherically Symmetric Vacuum-Solutions in a Higgs Scalar-Tensor Theory of Gravity

The exact static and spherically symmetric solutions of the vacuum field equations for a Higgs Scalar-Tensor theory (HSTT) are derived in Schwarzschild coordinates. It is shown that in general there exists no Schwarzschild horizon and that the fields are only singular (as naked singularity) at the center (i.e. for the case of a point-particle). However, the Schwarzschild solution as in usual general relativity (GR) is obtained for the vanishing limit of Higgs field excitations.     

Fluorescent Probe ABM for Screening Gastrointestinal Patient’s Immune State

The fluorescent probe-aminoderivative of benzanthrone, ABM (developed at Riga Technical University, Riga, Latvia) was used to characterize the membranes of lymphocytes of cancer patients: 46 patients with gastrointestinal diseases, 13 patients having different primary localizations with massive metastases and intoxication. Patients were divided into three groups: (1) with decreased fluorescence intensity, (2) normal fluorescence intensity, (3) increased fluorescence intensity. The lymphocytes distribution among subsets differed between groups, in correspondence to the level of florescence intensity. Surgical treatment affected the main immunological parameters and elevated the functional activity of lymphocytes. In the advanced tumors group, fluorescence intensity correlates with the survival rate. Results suggest that determination of lymphocytes functional activity by ABM can aid evaluation of the immune status in cancer patients.     

Trap elimination and reduction of size dispersion due to aging in CdS<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>Se<Subscript>1−<Emphasis Type="Italic">x</Emphasis></Subscript> quantum dots

Quantum Dots of CdS _x Se_1−x embedded in borosilicate glass matrix have been grown using Double-Step annealing method. Optical characterization of the quantum dots has been done through the combinative analysis of optical absorption and photoluminescence spectroscopy at room temperature. Decreasing trend of photoluminescence intensity with aging has been observed and is attributed to trap elimination. The changes in particle size, size distribution, number of quantum dots, volume fraction, trap related phenomenon and Gibbs free energy of quantum dots, has been explained on the basis of the diffusion-controlled growth process, which continues with passage of time. For a typical case, it was found that after 24 months of aging, the average radii increased from 3.05 to 3.12 nm with the increase in number of quantum dots by 190% and the size-dispersion decreased from 10.8% to 9.9%. For this sample, the initial size range of the quantum dots was 2.85 to 3.18 nm. After that no significant change was found in these parameters for the next 12 months. This shows that the system attains almost a stable nature after 24 months of aging. It was also observed that the size-dispersion in quantum dots reduces with the increase in annealing duration, but at the cost of quantum confinement effect. Therefore, a trade off optimization has to be done between the size-dispersion and the quantum confinement.