Ionic liquids and oligomer electrolytes based on the B(CN)4(-) anion; ion association, physical and electrochemical properties

The role of B(CN)(4)(-) (Bison) as a component of battery electrolytes is addressed by investigating the ionic conductivity and phase behaviour of ionic liquids (ILs), ion association mechanisms, and the electrochemical stability and cycling properties of LiBison based electrochemical cells. For C(4)mpyrBison and C(2)mimBison ILs, and mixtures thereof, high ionic conductivities (3.4 ≤σ(ion)≤ 18 mS cm(-1)) are measured, which together with the glass transition temperatures (-80 ≤T(g)≤-76 °C) are found to shift systematically for most compositions. Unfortunately, poor solubility of LiBison in these ILs hinders their use as solvents for lithium salts, although good NaBison solubility offers an alternative application in Na(+) conducting electrolytes. The poor IL solubility of LiBison is predicted to be a result of a preferred monodentate ion association, according to first principles modelling, supported by Raman spectroscopy. The solubility is much improved in strongly Li(+) coordinating oligomers, for example polyethylene glycol dimethyl ether (PEGDME), with the practical performance tested in electrochemical cells. The electrolyte is found to be stable in Li/LiFePO(4) coin cells up to 4 V vs. Li and shows promising cycling performance, with a capacity retention of 99% over 22 cycles.     

Zinc(II)‐Dipicolylamine‐Functionalized Polydiacetylene–Liposome Microarray: A Selective and Sensitive Sensing Platform for Pyrophosphate Ions

A microarray‐chip assay system for the fluorescence detection of phosphate‐containing analytes in aqueous media has been constructed from stimuli‐responsive polymerized poly(diacetylene)‐liposomes for the first time. Proper combination of the liposome components (Zn^II‐dipicolylamine for phosphate binding and an amine‐terminated component for anchoring the liposome onto an aldehyde‐derivatized glass plate), has led to a microarray chip that selectively detects pyrophosphate, an important biomarker, over competing anions, such as phosphate and adenosine triphosphate, with nanomolar sensitivity. The chip‐based assay shows advantages, such as high specificity and sensitivity, over solution‐based assays that use the same liposomes, and over known homogeneous molecular sensing systems.     

Adsorption-stress relationship in drying of silica/PVA suspensions

Mg-Al oxide obtained by thermal decomposition of NO(3)(-)-intercalated Mg-Al layered double hydroxide (NO(3)·Mg-Al LDH) was found to treat HNO(3), acting as both a neutralizer and fixative for NO(3)(-). The degree of NO(3)(-) removal increased with time, Mg-Al oxide quantity, and temperature. The NO(3)(-) removal could be represented by a first-order reaction. The apparent activation energy was 52.9 kJ mol(-1), confirming that NO(3)(-) removal by Mg-Al oxide proceeded under chemical reaction control. Furthermore, the adsorption of NO(3)(-) on Mg-Al oxide could be expressed by a Langmuir-type adsorption isotherm. The maximum adsorption amount and equilibrium adsorption constant were 3.8 mmol g(-1) and 1.33, respectively. The Gibbs free energy change was -18 kJ mol(-1), confirming that the uptake of NO(3)(-) from HNO(3) by Mg-Al oxide proceeded spontaneously.     

Higher harmonic anisotropic flow measurements of charged particles in Pb-Pb collisions at sqrt(s(NN)) = 2.76 TeV

We report on the first measurement of the triangular v3, quadrangular v4, and pentagonal v5 charged particle flow in Pb-Pb collisions at sqrt(s(NN)) = 2.76 TeV measured with the ALICE detector at the CERN Large Hadron Collider. We show that the triangular flow can be described in terms of the initial spatial anisotropy and its fluctuations, which provides strong constraints on its origin. In the most central events, where the elliptic flow v2 and v3 have similar magnitude, a double peaked structure in the two-particle azimuthal correlations is observed, which is often interpreted as a Mach cone response to fast partons. We show that this structure can be naturally explained from the measured anisotropic flow Fourier coefficients.     

Centrality dependence of the charged-particle multiplicity density at midrapidity in Pb-Pb collisions at sqrt[s(NN)] = 2.76 TeV

The centrality dependence of the charged-particle multiplicity density at midrapidity in Pb-Pb collisions at sqrt[s_{NN}]=2.76 TeV is presented. The charged-particle density normalized per participating nucleon pair increases by about a factor of 2 from peripheral (70%-80%) to central (0%-5%) collisions. The centrality dependence is found to be similar to that observed at lower collision energies. The data are compared with models based on different mechanisms for particle production in nuclear collisions.     

Measurement of impinging butane flame using combined optical system with digital speckle tomography

Three-dimensional density distributions of an impinging and eccentric flame were measured experimentally using a combined optical system with digital speckle tomography. In addition, a three-dimensional temperature distribution of the flame was reconstructed from an ideal gas equation based on the reconstructed density data. The flame was formed by the ignition of premixed butane/air from air holes and impinged upward against a plate located 24 mm distance from the burner nozzle. In order to verify the reconstruction process for the experimental measurements, numerically synthesized phantoms of impinging and eccentric flames were derived and reconstructed using a developed three-dimensional multiplicative algebraic reconstruction technique (MART). A new scanning technique was developed for the accurate analysis of speckle displacements necessary for investigating the wall jet regions of the impinging flame at which a sharp variation of the flow direction and pressure gradient occur. The reconstructed temperatures by the digital speckle tomography were applied to the boundary condition for numerical analysis of a flame impinged plate. Then, the numerically calculated temperature distribution of the upper side of the flame impinged plate was compared to temperature data taken by an infrared camera. The absolute average uncertainty between the numerical and infrared camera data was 3.7%.     

Analysis of stock prices of mining business

Stock exchanges have a diversity of so-called business groups and much evidence has been presented by covariance matrix analysis (Laloux et al. (1999) [6], Plerou et al. (2002) [7], Plerou et al. (1999) [8], Mantegna (1999) [9], Utsugi et al. (2004) [21] and Lim et al. (2009) [26]). A market-wide effect plays a crucial role in shifting the correlation structure from random to non-random. In this work, we study the structural properties of stocks related to the mining industry, especially rare earth minerals, listed on two exchanges, namely the TSX (Toronto stock exchange) and the TSX-V (Toronto stock exchange-ventures). In general, raw-material businesses are sensitively affected by the global economy while each firm has its own cycle. We prove that the global crisis during 2006–2009 affected the mineral market considerably. These two aspects compete to control price fluctuations. We show that the internal cycle overwhelms the global economic environment in terms of random matrix theory and overlapping matrices. However, during the period of 2006–2009, the effect of the global economic environment emerges. This result is well explained by the recent global financial/economic crisis. For comparison, we analyze the time stability of business clusters of the KOSPI, that is, the electric/electronic business, using an overlapping matrix. A clear difference in behavior is confirmed. Consequently, rare earth minerals in the raw-material business should be classified not by standard business classifications but by the internal cycle of business.     

Detection of small intrahepatic metastases of hepatocellular carcinomas using diffusion-weighted imaging: comparison with conventional dynamic MRI

Purpose

The purpose of our study was to compare diffusion-weighted MR imaging (DWI) with conventional dynamic MRI in terms of the assessment of small intrahepatic metastases from hepatocellular carcinoma (HCC).

Materials and Methods

In 24 patients with multifocal, small (≤2 cm) intrahepatic metastatic foci of advanced HCC, a total of 134 lesions (≤1 cm, n=81; >1 cm, n=53) were subjected to a comparative analysis of hepatic MRI including static and gadopentetate dimeglumine-enhanced dynamic imaging, and DWI using a single-shot spin-echo echo-planar MRI (b values=50, 400 and 800 s/mm²), by two independent reviewers.

Results

A larger number of the lesions were detected and diagnosed as intrahepatic metastases on DWI [Reviewer 1, 121 (90%); Reviewer 2, 117 (87%)] than on dynamic imaging [Reviewer 1, 107 (80%); Reviewer 2, 105 (78%)] (P<.05). For the 81 smaller lesions (≤1 cm), DWI was able to detect more lesions than dynamic imaging [Reviewer 1, 68 (84%) vs. 56 (69%), P=.008; Reviewer 2, 65 (80%) vs. 55 (68%), P=.031], but there was no statistically significant difference between the two image sets for larger (>1 cm) lesions.

Conclusion

Due to its higher detection rate of subcentimeter lesions, DWI could be considered complementary to dynamic MRI in the diagnosis of intrahepatic metastases of HCCs.     

Two-dimensional crystallization of carboxylated benzene oligomers

Various carboxylic acid substitution patterns on the 1,3,5-triphenylbenzene nucleus were explored, and their influence on the symmetry of the resulting two-dimensional (2D) crystal structures was assessed. The symmetry of 1,3,5-benzenetribenzoic acid (H(3)BTB) was reduced by modifying the substitution pattern of the arene and/or adding an additional carboxylic acid. Four analogues belonging to various point groups were studied. Comparison of the monolayers of the analogues to that of H(3)BTB shows that plane group symmetry and molecular symmetry are not correlated: H(3)BTB and its analogues exhibit the same plane group p2 at the heptanoic acid/graphite interface. The 2D crystal structure of the H(3)BTB analogues is more strongly controlled by the geometry of hydrogen-bonding interactions rather than molecular symmetry. Other significant observations in this study include porosity, uncommon hydrogen-bonding motifs, and an unusually high number of inquivalent molecules (Z' = 3) present in the 2D crystal of the lowest symmetry analogue. This research demonstrates that reduction of molecular symmetry based on geometric modification of noncovalent interactions allows for control over porosity of the 2D crystals (close-packed structures to nanoporous networks) without changing the core shape of the molecule.