Investigations on Deposit Formation in the Holes of Diesel Injector Nozzles

Current developments in fuels and emissions regulations are resulting in an increasingly severe operating environment for diesel fuel injection systems. The formation of deposits within the holes or on the outside of the injector nozzle can affect the overall system performance. The rate of deposit formation is affected by a number of parameters, including operating conditions and fuel composition. For the work reported here an accelerated test procedure was developed to evaluate the relative importance of some of these parameters in a high pressure common rail fuel injection system. The resulting methodology produced measurable deposits in a custom made injector nozzle on a single cylinder engine. The results indicate that fuels containing 30%v/v and 100% Fatty Acid Methyl Ester (FAME), that does not meet EN 14214 produced more deposit than an EN590 petroleum diesel fuel. Overall, the addition of zinc to the fuel had the biggest effect on deposit formation and resulted in a 12.2% decrease in Indicated Mean Effective Pressure (IMEP). The effects of zinc were unexpectedly reduced when it was added to fuel containing 30%v/v biodiesel. Reducing the common-rail pressure with 30%v/v biodiesel (no added zinc) increased the loss in IMEP. Raising the air and fuel temperatures by 40°C and 30°C respectively showed no bigger loss in IMEP. The results indicate that deposit formation may continue after engine shut down. © 2011 Society of Automotive Engineers of Japan, Inc. and SAE International

Three-body correlations and finite-size effects in the Moore--Read states on a sphere

Two- and three-body correlations in partially filled degenerate fermion shells are studied numerically for various interactions between the particles. Three distinct correlation regimes are defined, depending on the short-range behavior of the pair pseudopotential. For pseudopotentials similar to those of electrons in the first excited Landau level, correlations at half-filling have a simple three-body form consisting of the maximum avoidance of the triplet state with the smallest relative angular momentum R_3=3. In analogy to the superharmonic criterion for Laughlin two-body correlations, their occurrence is related to the form of the three-body pseudopotential at short range. The spectra of a model three-body repulsion are calculated, and the zero-energy Moore--Read ground state, its +-e/4-charged quasiparticles, and the magnetoroton and pair-breaking bands are all identified. The quasiparticles are correctly described by a composite fermion model appropriate for Halperin's p-type pairing with Laughlin correlations between the pairs. However, the Moore--Read ground state, and specially its excitations, have small overlaps with the corresponding Coulomb eigenstates when calculated on a sphere. The reason lies in surface curvature which affects the form of pair pseudopotential for which the "R_3>3" three-body correlations occur. In finite systems, such pseudopotential must be slightly superharmonic at short range (different from Coulomb pseudopotential). However, the connection with the three-body pseudopotential is less size-dependent, suggesting that the Moore--Read state and its excitations are a more accurate description for experimental nu=5/2 states than could be expected from previous calculations.Comment: 12 pages, 12 figures, submitted to PR

Microwave-Assisted Depolymerisation of Biolignintm in the Presence of Zeolite-Based Catalysts

In this work a microwave-assisted depolymerisation of lignin in the presence of zeolite-based catalysts was studied in order to obtain a valuable bio-oil. Catalytic activity of H-ZSM-5, H-Y, H-BETA and H-Mordenite containing nano-NiO particles was investigated in the depolymerisation of BioligninTM. The catalysts were prepared by mechanochemical dry milling (MCDM) method following by calcination under air at 400 °C. The highest bio-oil yield of 8.78 wt. %, was obtained in the presence of NiO-containing H-ZSM-5

Edge excitations and Topological orders in rotating Bose gases

The edge excitations and related topological orders of correlated states of a fast rotating Bose gas are studied. Using exact diagonalization of small systems, we compute the energies and number of edge excitations, as well as the boson occupancy near the edge for various states. The chiral Luttinger-liquid theory of Wen is found to be a good description of the edges of the bosonic Laughlin and other states identified as members of the principal Jain sequence for bosons. However, we find that in a harmonic trap the edge of the state identified as the Moore-Read (Pfaffian) state shows a number of anomalies. An experimental way of detecting these correlated states is also discussed.Comment: Results extended to larger systems. Improved presentatio

Cytotoxic effects of selected gold(III) complexes on the murine BCL-1 B lineage leukaemia cell line

In recent years, gold(III) complexes have attracted great interest because of their cytotoxicity to cancer cells. We investigated the cytotoxic effects of three newly synthesised gold(III) complexes, [Au(en)Cl 2] + (dichloride (ethylendiamine) aurate(III)-ion), [Au(dach)Cl 2] (dichloride (1,2- diaminocyclohexane) aurate(III)-ion) and [Au(bipy)Cl 2] + (dichloride (2,2'-bipyridyl) aurate(III)-ion), on the murine BCL-1 B lineage leukaemia cell line. The cytotoxicity of these gold(III) complexes was evaluated by cytotoxic assay (MTT test). The results showed that all of the tested gold(III) complexes displayed a cytotoxic effect on BCL-1 cells. The concentration decrease was followed by a marked increase in BCL-1 cell viability. At a concentration of 125 μM, which we suppose could be used in vivo, the [Au(bipy)Cl 2] + complex showed the greatest cytotoxic effects among the tested gold(III) complexes and similar cytotoxicity asto the cisplatinum that we used as control. Among the tested gold(III) complexes, [Au(en)Cl 2] +was the least cytotoxic to BCL-1 cells. In line with the obtained results, we suggest that the [Au(bipy)Cl 2] + complex should be tested in vivo in experimental models of B cell leukaemia

Remaining life of TI-6AL-4V ELI HIP IMPLANT WITH A CRACK

Fatigue failure is the main issue in design of hip implants. One way to prolong fatigue life is to use newly developed Ti6Al4V Extra Low Interstitials (ELI) alloy. As the most critical part, hip neck has been in the focus of this analysis, keeping in mind that the lower the thickness is, the higher the movement of joint may be, but reducing remaining life of implants with a crack at the same time. In this research extended Finite Element Method (xFEM) is used to analyse this effec

Indirect Inference for Time Series Using the Empirical Characteristic Function and Control Variates

We estimate the parameter of a stationary time series process by minimizing the integrated weighted mean squared error between the empirical and simulated characteristic function, when the true characteristic functions cannot be explicitly computed. Motivated by Indirect Inference, we use a Monte Carlo approximation of the characteristic function based on iid simulated blocks. As a classical variance reduction technique, we propose the use of control variates for reducing the variance of this Monte Carlo approximation. These two approximations yield two new estimators that are applicable to a large class of time series processes. We show consistency and asymptotic normality of the parameter estimators under strong mixing, moment conditions, and smoothness of the simulated blocks with respect to its parameter. In a simulation study we show the good performance of these new simulation based estimators, and the superiority of the control variates based estimator for Poisson driven time series of counts.Comment: 38 pages, 2 figure

A cross-country examination on the fear of covid-19 and the sense of loneliness during the first wave of covid-19 outbreak

The aim of the current study is to examine gender, age. and cross-country differences in fear of COVID-19 and sense of loneliness during the lockdown, by comparing people from those countries with a high rate of infections and deaths (e.g., Spain and Italy) and from countries with a mild spread of infection (e.g., Croatia, Serbia, Slovakia, Slovenia, and Bosnia and Herzegovina). A total of 3876 participants (63% female) completed an online survey on “Everyday life practices in COVID-19 time” in April 2020, including measures of fear of COVID-19 and loneliness. Males and females of all age groups in countries suffering from the powerful impact of the COVID-19 pandemic reported greater fear of COVID-19 and sense of loneliness. In less endangered countries, females and the elderly reported more symptoms than males and the young; in Spanish and Italian samples, the pattern of differences is considerably more complex. Future research should thoroughly examine different age and gender groups. The analysis of emotional well-being in groups at risk of mental health issues may help to lessen the long term social and economic costs due to the COVID-19 outbreak

Minimum Atom-Bond Sum-Connectivity Index of Trees With a Fixed Order and/or Number of Pendent Vertices

Let $d_u$ be the degree of a vertex $u$ of a graph $G$. The atom-bond sum-connectivity (ABS) index of a graph $G$ is the sum of the numbers $(1-2(d_v+d_w)^{-1})^{1/2}$ over all edges $vw$ of $G$. This paper gives the characterization of the graph possessing the minimum ABS index in the class of all trees of a fixed number of pendent vertices; the star is the unique extremal graph in the mentioned class of graphs. The problem of determining graphs possessing the minimum ABS index in the class of all trees with $n$ vertices and $p$ pendent vertices is also addressed; such extremal trees have the maximum degree $3$ when $n\ge 3p-2\ge7$, and the balanced double star is the unique such extremal tree for the case $p=n-2$.Comment: 20 pages, 4 figure