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The primary objective of this research paper is to control the material and process defects in polymer melt extrusion film casting (EFC) process for linear chain architecture polyethylene (PE) resins through polymer blending methodology. Extrusion film casting is a well-known industrially important manufacturing process that is used to manufacture thousands of tons of polymer/plastic films/sheets and coated products. In this research, the necking defect in an EFC process has been studied experimentally for a linear low density polyethylene (LLDPE) resin and attempts have been made to control its necking by blending in a long chain branched (LCB) low density polyethylene (LDPE) resin. The blending methodology is based on the understanding that a LDPE resin displays enhanced resistance to necking as compared to the LLDPE resin. It is found that added LDPE resin enhances necking resistance for the primary LLDPE resin. Further, as the LDPE concentration increases in the blend formulation, the necking is further reduced as compared to pure LLDPE. Analogous to past studies on EFC of linear and long chain branched architecture containing PEs, it is observed that as the LDPE is increased in the blend formulations, the formulations displayed enhanced melt elasticity and extensional strain hardening in rheological studies. It is concluded from this study that polyethylene resins having linear chain architecture can be made amenable to enhanced resistance to necking using appropriate amount of a long chain branched resins. Finally, process defects such as the draw resonance onset could be shifted to higher draw ratios as the LDPE level is increased in the LLDPE-LDPE blend formulation. [ABSTRACT FROM AUTHOR]

• Spin 1/2 Heisenberg antiferromagnetic order is observed in Gd3+-based nanoparticles. • Susceptibility data agrees with theory confirming antiferromagnetic coupling. • The Néel temperature is T N ∼ 17 K. • Constriction in the MH curves is presumably due to the antiferromagnetic coupling. We report observations of spin 1 2 Heisenberg antiferromagnetic order in nanoparticle ensembles of G d 1.89 N i 0.02 Z n 0.03 F e 0.55 O 4 and G d 1.39 N i 0.10 Z n 0.02 F e 0.89 O 4. The staggered molar susceptibility, χ m (T) , of the ensembles varies as 1 / T as T → T N ≈ 17 K. Below T N , the χ m T is directly proportional to the temperature before showing another upturn. An excellent agreement between the experimental χ m (T) and theoretical models (Bonner-Fisher and Eggert) confirms spin 1 2 antiferromagnetic coupling within the linear chains of electron spins of the ensembles. The exchange constant is J k B = 17 K. The antiferromagnetic exchange interaction is also signified by a constriction at the middle of the hysteresis loop, at H = 0 , which becomes narrow at 5 K. We argue that the origin of the exchange interaction is in the quantum interference of the Bloch waves with the composite energy states of the domain walls. [ABSTRACT FROM AUTHOR]

In this paper, we present a trajectory period folding method for numerical modelling of nuclear transformations. The method uses the linear chain method, commonly applied for modelling of isotopic changes in matter. The developed method folds two consecutive periods of time and forms linear chain representations. In the same way as in the linear chain method, the mass flow of straight nuclide-to-nuclide transitions following the formation of nuclide transmutation chains in every step is considered over the total period of interest. Therefore, all quantitative data about the isotopic transformations for the period beyond a particular calculation step are preserved. Moreover, it is possible to investigate the formation history of any isotope from the beginning of irradiation to the arbitrary time step, including cooling periods and multi-recycling for any designed nuclear fuel cycle. We present a case study for the transition from 238U to 239Pu and define the properties of the developed method and its possible applications in reactor physics calculations. [ABSTRACT FROM AUTHOR]

Simple structural models and a previously proposed theory have been used for estimating bandgap widths, effective masses, and effective velocities of charge carriers in sheet- and zigzag-type nanoribbon and chain structures of 22 graphene-like ANB8 –N compounds. It is established that the decoration of nanoribbons and chains by A and B atoms leads to cardinal changes in the electron spectra of these structures. [ABSTRACT FROM AUTHOR]

The features of phonon spectra and their effect on the vibrational heat capacity of linear chains of inert gas atoms adsorbed onto a substrate, which is the surface of nanotubes bound to a nanobundle. The influence of the substrate results both in a shift of the lower limit of the chain spectrum from zero, and in mechanical stress in the chain (its extension or compression) also. It is shown that in the case of a compressed chain, the non-central interaction between atoms is negative (repulsive), it results in a shift of the lower boundary of the spectrum of transverse vibrations to low frequencies and to a shortening of the part of the specific heat temperature dependence in which this dependence is close to exponential. Heterogeneity of the nanobundle structure can cause a change in the distances between atoms of the chain. It is shown both and analytically and numerically, that as a result of it, discrete levels with frequencies both above and below the quasi-continuous spectrum band can appear in the phonon spectrum of the chain. The discrete levels with frequencies below the quasi-continuous spectrum band lead to a further shortening of the temperature interval at which the temperature dependence of the specific heat is close to the exponential one. [ABSTRACT FROM AUTHOR]

We use a neural network approach to explore the inverse problem of Bloch oscillations in a monoatomic linear chain: given a signal describing the path of oscillations of electrons as a function of time, we determine the strength of the applied field along the direction of motion or, equivalently, the lattice spacing. We find that the proposed approach has more than 80% of accuracy classifying the studied physical parameters. [ABSTRACT FROM AUTHOR]

Hepatic de-novo lipogenesis is a metabolic process implemented in the pathogenesis of type 2 diabetes. Clinically, the rate of this process can be ascertained by use of labeled acetate and stimulation by fructose administration. A systems pharmacology model of this process is desirable because it facilitates the description, analysis, and prediction of this experiment. Due to the multiple enzymes involved in de-novo lipogenesis, and the limited data, it is desirable to use single functional expressions to encapsulate the flux between multiple enzymes. To accomplish this we developed a novel simplification technique which uses the available information about the properties of the individual enzymes to bound the parameters of a single governing 'transfer function'. This method should be applicable to any model with linear chains of enzymes that are well stimulated. We validated this approach with computational simulations and analytical justification in a limiting case. Using this technique we generated a simple model of hepatic de-novo lipogenesis in these experimental conditions that matched prior data. This model can be used to assess pharmacological intervention at specific points on this pathway. We have demonstrated this with prospective simulation of acetyl-CoA carboxylase inhibition. This simplification technique suggests how the constituent properties of an enzymatic chain of reactions gives rise to the sensitivity (to substrate) of the pathway as a whole. [ABSTRACT FROM AUTHOR]

The HOIP ubiquitin E3 ligase generates linear ubiquitin chains by forming a complex with HOIL-1L and SHARPIN in mammals. Here, we provide the first evidence of linear ubiquitination induced by a HOIP orthologue in Drosophila. We identify Drosophila CG11321, which we named Linear Ubiquitin E3 ligase ( LUBEL), and find that it catalyzes linear ubiquitination in vitro. We detect endogenous linear ubiquitin chain-derived peptides by mass spectrometry in Drosophila Schneider 2 cells and adult flies. Furthermore, using CRISPR/Cas9 technology, we establish linear ubiquitination-defective flies by mutating residues essential for the catalytic activity of LUBEL. Linear ubiquitination signals accumulate upon heat shock in flies. Interestingly, flies with LUBEL mutations display reduced survival and climbing defects upon heat shock, which is also observed upon specific LUBEL depletion in muscle. Thus, LUBEL is involved in the heat response by controlling linear ubiquitination in flies. [ABSTRACT FROM AUTHOR]

Here, we consider a class of generalized linear chains; that is, the ladder-like chains as a perturbation of a 2 n path by adding consecutive weighted edges between opposite vertices. This class of chains in particular includes a big family of networks that goes from the cycle, unicycle chains up to ladder networks. In this article, we obtain the Green function, the effective resistance, and the Kirchhoff index of ladder-like chains in terms of the Green function, the effective resistance, and the Kirchhoff index of the path. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The self-assembly reaction of zinc ions with tetracyanometalates in the presence of the tridentate chelated ligand 2,2′:6′,2′′-terpyridine (terpy) yielded three cyanide-bridged bimetallic compounds of general formula Zn(terpy)(H2O) M(CN)4 [ M = Ni ( 1), Pd ( 2), Pt ( 3)]. Compounds 1- 3 were characterized by X-ray diffraction (XRD), infrared spectroscopy (IR), and thermogravimetric (TG) analysis. Single-crystal XRD analysis revealed that compounds 1- 3 are isostructural and the structure consists of [Zn(terpy)(H2O)]2+ moieties and [ M(CN)4]2- units linked alternatively to generate a one-dimensional (1D) linear chain. The chains are further connected together through hydrogen bonding and π-π stacking interactions, forming a 3D supramolecular network. IR spectroscopic analysis indicated the presence of cyanide groups and terpy ligands in the structure. TG and powder XRD results showed that compounds 1- 3 have higher thermal stabilities and exhibited irreversible for desorption/resorption of one coordinated water molecule. [ABSTRACT FROM AUTHOR]

Exact solution of a coupled spin–electron linear chain composed of localized Ising spins and mobile electrons is found. The investigated spin–electron model is exactly solvable by the use of a transfer-matrix method after tracing out the degrees of freedom of mobile electrons delocalized over a couple of interstitial (decorating) sites. The exact ground-state phase diagram reveals an existence of five phases with different number of mobile electrons per unit cell, two of which are ferromagnetic, two are paramagnetic and one is antiferromagnetic. We have studied in particular the dependencies of compressibility and specific heat on temperature and electron density. [ABSTRACT FROM AUTHOR]

In this work we propose a theoretical study of odd-even effects in charge transport through a linear three terminal chain device. We use the Landauer approach, with the electronic structure treated at tight binding (TB) level and model the self-energy as an energy independent parameter. Moreover, we use decimation techniques to renormalize the system, reducing it into a 3 × 3 matrix, so as to make an analytical treatment. By varying the size of the chain, we alter not only the parity of the full system but also the parity of each possible pathway and show how odd-even effect appears in the transmission function, local density of states and the behavior of the electrical current as function of the parity. Our theoretical approach reveals, in a clear way, how the parity of each branch competes with the parity of the full system to the conductance values near the Fermi level. • The behavior of odd-even effects in a linear three-terminal devices shows a high dependence with symmetry. • In the transmission function, the number of sistes of the branches competes with the total number of sistes in the system. • Even-odd effects depends of both: total number of sites and pathway number of sites. [ABSTRACT FROM AUTHOR]

Abstract: Two new Cd coordination polymers, [Cd(5-Nisp)(e-urea)]n (1), and [Cd2(5-Hisp)2(e-urea)2(en)]n (2), (where 5-Nisp=5-nitroisophthalate; 5-Hisp=5-hydroxyisophthalate; e-urea=ethyleneurea; en=1,2-ethanediamine), have been urothermally synthesized by using ethyleneurea hemihydrate as the solvent. Single-crystal X-ray diffraction analyses reveal that both 1 and 2 have linear chain sub-structures linked by 5-Nisp ligands or 5-Hisp ligands into three-dimensional frameworks. The thermogravimetric behavior and the photoluminescent properties of 1 and 2 were studied. [Copyright &y& Elsevier]

Abstract: The generation of polarity in the solid state necessitates ordered, polar basic-building units (BBUs). This paper examines the evolution of ordered BBUs of 1D chains constructed of early transition metals (ETMs) and late transition metals. The cause of polar distortion orientation is illustrated with subtle alterations in the heterotypic structures of one previously reported compound (CuNbOF5(H2O)2(pyz)3) and three new hybrid materials, presented here: CuNbOF5(H2O)4(pyz)2 (1), CuVOF5(H2O)4(pyz)2 (2) and CuVOF5(H2O)2(pyz)3 (3) (pyz=pyrazine). In contrast to the [NbOF5]2− octahedra of CuNbOF5(H2O)2(pyz)3 and compound (1) that have oxide ligands within the 1D BBUs, the [VOF5]2− octahedra of compounds (2) and (3) contain disordered oxide ligands perpendicular to the chains. To create polar 1D BBUs in the solid state, one must have an understanding of how to direct distortions. We demonstrate that the choice of specific polar BBUs within a distinct environment is necessary for orientational order of the ETM anions. [Copyright &y& Elsevier]

Abstract: The solvent-mediated crystal-to-crystal transformation was observed from yellow crystal of NiCl2(CH3OH)2(1,4-dioxane)0.5 (1) to green crystal of [NiCl2(H2O)2(1,4-dioxane)](1,4-dioxane) (2) under high humidity or adding of H2O in CH3OH/1,4-dioxane solution. The μ-Cl2 bridge in 1 replaced by 1,4-dioxane bridge in 2. In 1, the chlorine-bridged linear chains of NiCl2(CH3OH)2 and 1,4-dioxane molecules stack along the b- and c-axis alternatively with hydrogen bonds intrachain, interchain, between chain and solvent. These hydrogen bonds and dipolar interaction between ferromagnetic coupling chlorine-bridged chains result in long-range ferromagnetic ordering at 3.1K and a strong frequency dependence of the ac-susceptibilities associated to domain structures with very large shape anisotropy was observed below 3.1K. In 2, layers of 1,4-dioxane-bridged linear chains of NiCl2(H2O)2(1,4-dioxane) are intercalated by layer of 1,4-dioxane molecules with hydrogen bonds between chain and solvent. Compound 2 is paramagnet to 2K. [Copyright &y& Elsevier]

Abstract: We study the lattice dynamics of the zinc-blende (ZB) allotropic form of bulk group-III nitrides using an approach based on the linear chain model. Supported by the fact that the longitudinal oscillations and the transverse oscillations are effectively decoupled, the relationship between the three dimensional (3D) and linear chain (1D) force constants has been reported. It is possible then to fit the 3D bulk force constants (and consequently the whole dynamical matrix) from the information related to few points, either experimental or theoretical. In particular, we derive the dispersion relation and the corresponding force constants of BN, AlN, GaN and InN. Our results are in good agreement with previous ab initio results. [Copyright &y& Elsevier]

The dynamical response of one dimensional chains containing 55 till 309 atoms is investigated using a restricted molecular dynamics simulation scheme. The total momentum correlation function of an electron cloud shows resonances that are related to different collective excitation modes of the nano plasma. Spatially resolved cross correlation functions are calculated to deduce the spatial structure and strength of these resonance modes. The dependence of the corresponding resonance frequencies on temperature, density and chain size is investigated. The width of the resonances is analyzed in terms of a mode dependent collision frequency. [ABSTRACT FROM AUTHOR]

Abstract: Cluster dynamics is often used in the multi-scale procedure to link atomistic and macroscopic approaches, in particular when modelling precipitation processes. To extend its use to concentrated alloys, it is necessary to take into account accurately the exclusion zones and their overlap. By investigating the one-dimensional case, one obtains an exact formula for these zones, and its generalization to higher dimensions is proposed. By integrating cluster fragmentation/coagulation processes into cluster dynamics equations, a perfect agreement between atomistic simulations (Kinetic Monte Carlo) and cluster dynamics is reached on the whole range of concentrations for kinetics which govern microstructure in one dimension. [Copyright &y& Elsevier]

The Davydov's soliton propagation in the linear polymer chain is analyzed numerically by solving the discrete equations of motion for exciton and phonon amplitudes. The main difference with respect to the results of continual approximation is that two exciton–phonon coupling constants influence separately the soliton behavior. Their influence is studied both in the ideal chain and the chain with single impurity. [ABSTRACT FROM AUTHOR]

Abstract: The first linear bis(chlorido)-bridged Cu(II) compound with the ligand 2-amino-5-nitropyrimidine (abbreviated as anpyr), [Cu(μ-Cl)2(anpyr)2] n , has been synthesized and fully characterized by spectroscopy, EPR and X-ray structure analysis. The basal plane around the Cu(II) ion is formed by two chloride anions with a Cu–Cl distance of 2.2513(6)Å and two nitrogen atoms of two trans-located anpyr ligands with a Cu–N distance of 2.068(2)Å. The apical positions of the distorted octahedral geometry are formed by two Cl anions of a neighbouring unit with a distance of 2.8690(8)Å. The Cu–Cl–Cu angle is 94.75(3)°, while the Cu–Cu distance is 3.791Å. The Cu–bis-μ-chlorido-Cu array provides in this way a 2D linear chain. A neighbouring pair of symmetry-related polynuclear chains is linked through hydrogen bonds with a N···N distance 3.027(3)Å, forming into a kind of Watson–Crick-like pair of hydrogen bonds. Another H-bond is formed by the amine nitrogen to one of the chloride anions with a N···Cl distance 3.248(2)Å. The EPR powder spectrum appears as rhombic with g 1 2.20, g 2 2.12; g 3 2.05, with unresolved hyperfine splittings. Analysis of the magnetic susceptibility measurements, recorded from 2 to 300K, indicates a very weak antiferromagnetic interaction between the metal ions (J =−2cm−1). [Copyright &y& Elsevier]

A novel organic-templated zincophosphate, namely (C6H16N2)[Zn(HPO4)2], was hydrothermally synthesized and X-ray single-crystal structural analysis reveals that the anions [Zn(HPO4)2]2–, which have square-twisted chains containing corner-sharing four-rings of alternating ZnO4 and PO4 tetrahedra, are assemblied via self-complementary strong and symmetrical hydrogen-bonding R22(8) synthons between the phosphate groups into three-dimensional hydrogen bond frameworks featuring three-dimensional intersecting pseudochannels. The doubly protonated 2,5-dimethylpiperazinium cations are attached to the three-dimensional inorganic framework via N-H···O hydrogen bonds to strengthen the 3-D network. [ABSTRACT FROM AUTHOR]

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SQUID magnetometers have been fabricated from series arrays of YBa/sub 2/Cu/sub 3/O/sub 7/ dc SQUIDs by pulsed laser film deposition and ion mill patterning techniques. The array was designed either in linear chain with flux focusers or in meander structure. The arrays consisted of 50-130 step-edge junction SQUIDs and each SQUID had inductance of 20-40 pH with 2-5 /spl mu/m junction width. A linear array of 50 SQUIDs showed a modulation amplitude of 150 /spl mu/V which corresponds to a gain of /spl sim/10. One of 80 SQUID meander arrays had a gain of as high as 50. These results provide feasibility of the series array of SQUIDs in the direct readout SQUID amplifier circuitry with wide bandwidth. Larger number SQUID arrays and processes to increase the gain to the theoretical value need to be studied. [ABSTRACT FROM PUBLISHER]

Superconducting vibronic interaction in the vibronic superconductivity motif has been studied in the Hückel framework for ( AB) chain systems. Within the on-site and nearest-neighbor approximation a new vibronic constant, ∂α/∂ L, has been introduced, of which the importance has been discussed. The effect of the vibronic operator, Δ, has also been studied. It is also concluded that the size-dependence of the superconducting vibronic interaction also exists in the ( AB) chain systems. [ABSTRACT FROM AUTHOR]