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This study examines how actors organized collective efforts to initiate the project and navigated their way forward, even though the ultimate outcome was not clearly defined. To address this question, we explore the potential of the philosophical tradition of pragmatism. This approach foregrounds duality, recursiveness and temporality of collective activities and offers a new and compelling way to understand and address the challenges actors face in organizing and managing the front-end. By accounting for both the situatedness of actions in the wider social and relational contexts, and by connecting the flow of present experience to the interpretations of the past and future, pragmatism holds the potential for integrating theory the actuality of lived experience in its continuous unfolding while accounting for actors’ transformative agency. By drawing on a real-time longitudinal study of conception of the program of the Restoration and Renewal (R&R) of the Palace of Westminster, we show how participants face the challenge of understanding and managing complex tensions that continually arise due to a duality of mobilization (between seeking consensus and expanding divergent possibilities) and a duality of transformation (between forming a bold vision of the future and translating abstract goals into concrete actions). To tackle the challenges, participants create strategic accounts that are stable enough to be practically feasible in current circumstances, but also sufficiently adaptable to pursue future possibilities in ways that challenge prevailing approaches. By showing how participants cope with these challenges by creating spaces of experimentation and constructing flexible boundaries this study contributes to the literature on management of project's front-end.

The ability to transform the crystal structure of metals in the solid state enables tailoring their physical, mechanical, electrical, thermal, and optical properties in unprecedented ways. We demonstrate a martensitic phase transformation from a face-centered-cubic (fcc) structure to a hexagonal-close-packed (hcp) structure that occurs in nanosecond timescale in initially near-defect-free single-crystal silver (Ag) microcubes impacted at supersonic velocities. Impact-induced high pressure and high strain rates in Ag microcubes cause impact orientation dependent extreme micro- and nano-structural transformations. When a microcube is impacted along the [100] crystal symmetry direction, the initial fcc structure transforms into an hcp crystal structure, while impact along the [110] direction does not produce phase transformations, suggesting the predominant role played by the stacking faults generated in the [100] impact. Molecular dynamics simulations at comparable high strain rates reveal the emergence of such stacking faults that coalesce, forming large hcp domains. The formation of hcp phase through the martensitic transformation of fcc Ag shows new potential to dramatically improve material properties of low-stacking-fault energy materials.

Three nickel electrodeposits with comparable grain size were synthesized by tailoring the electrodeposition conditions. Thorough microstructural characterizations including electron backscatter diffraction, ion channeling contrast imaging, electron channeling contrast imaging, transmission Kikuchi diffraction, transmission electron and high annular dark-field imaging were applied. The deposits contain a high density of twin boundaries with similar microstructures in terms of grain boundary character. These materials were annealed at various temperatures to study the microstructural evolution, and hence, their thermal stability. The differences in the character of twin boundaries and morphology of the grain boundaries in as-deposited state and their influence on the microstructural evolution at elevated temperatures are analyzed. The importance of incoherent twin boundaries, and the interaction of mobile general high angle boundaries with stationary boundaries are discussed. Finally, an optimal design for high thermal stability is proposed, based on the mechanisms that were inferred from the results. Keywords: Thermal stability, Twin boundaries, Annealing, Grain boundary engineering, Nickel, Electrodeposition

The features of the internationalization of emerging market multinational companies (EMNCs) create a laboratory for extending theory. In this paper, we argue that a high level of asymmetry between prior knowledge and a non-incremental commitment, such as an acquisition, lies at the core of understanding these types of internationalization processes. Our proposed theoretical view is that while some uncertainties in opportunity development are known to the firms and can be managed by available knowledge, disruptive commitments can result in complexes of unstable and unilineal dynamics that bring about unexpected – and hence unforeseeable – uncertainties. These uncertainties may be a source of future unintended consequences that will have an impact on the firm as the internationalization process unfolds. This view is used for analysis of a longitudinal case study concerning the acquisition of a Swedish firm, Vargon Alloys, by the Turkish corporation Yildirim Group, focusing on the opportunity discovery and exploitation period between 2008 and 2013. By dividing uncertainty into two types (foreseeable and unforeseeable) and analysing the hidden problems that emerged after the sudden fusion of the two networks, the study nuances understanding of the emergent and non-orderly nature of the internationalization process as it unfolds. From a process point of view, the study may aid deeper understanding of complications when discovering and exploiting opportunities.

Multilayer nickel-tungsten coatings were deposited on carbon steel using the pulse reverse current technique. Nickel-tungsten layered structure coatings were developed using the continuous and alternative variation of pulse duty cycle at two specific and fixed values. In these coatings, the multilayer structure is composed of two nickel-tungsten layers with alternating chemical compositions of 25 wt%W and 11 wt%W. Dynamic electrochemical impedance spectroscopy (DEIS) revealed three time constants in the electrical equivalent circuit corresponding to the electrodeposition mechanism of nickel-tungsten. In order to evaluate the electrochemical behavior of the multilayer structure, the investigation of the multilayer coatings was carried out via cyclic potentiodynamic polarization, in a sulfuric acid media which contained chloride ions. Cyclic voltammetry test was introduced and subsequently employed as a novel electrochemical evaluation for layered structures. Morphological, elemental and Raman analysis were carried out. Analyzing the surface products revealed that nickel tends to dissolve in presence of tungsten, and even more in an electrolyte containing chloride ions. It was also revealed that the diffusive species of the electrolyte encountered a larger interface in multilayer structures. Hence, they spread out along and throughout the active layers; which significantly delays the penetration towards the substrate. Enhanced service life of the noble layers is achieved owing to the galvanic effect. According to the findings, these kinds of coatings are more resistant to localized attack in comparison to monolithic coatings.

Background Waardenburg syndrome (WS) is a neurocristopathy characterized by hearing impairment and pigmentary disturbances in hair, eyes, and skin. WS is clinically heterogeneous and can be subdivided into four major types (WS1–WS4) where WS4 or Shah–Waardenburg is diagnosed when WS2 is accompanied by Hirschsprung disease (HD). Mutations of SOX10 , EDN3 / EDNRB have been identified in association with WS4. This study was aimed to determine the pathogenic variant in an Iranian pedigree affected with WS4. Method A two-generation pedigree with three affected members and considerable phenotypic heterogeneity was recruited. The proband was a 15-year-old boy, with severe to profound sensorineural hearing impairment, heterochromia iridis, hypoplastic blue eyes and Hirschprung disease. The other two also presented characteristics of WS2 and complained of chronic constipation with normal anorectal reflex. Sequencing of all exons and exon-intron boundaries of SOX10 , EDN3 / EDNRB revealed a heterozygous variant c.422T > C in exon 3 of SOX10 confirmed by a series of evidence to be pathogenic. It resulted in p.L141P at the protein level. Leucin 141 is located in Nuclear Export signal, HMG box of the protein. Conclusion This study is the first report of a WS4 family in the Iranian population. The mutation is associated with distinctive phenotypic profile (association of anosmia and chronic constipation with SOX10 mutations) and could further improve diagnosis and counseling of WS in the Iranian population and can contribute to phenotype-directed genetic analysis.

A common cause for premature bearing failures in wind turbine gearboxes are the so-called White Etching Cracks (WEC). These undirected, three-dimensional cracks are bordered by regions of altered microstructure and ultimately lead to a cracking or spalling of the raceway. An accelerated WEC test was carried out on a FE8 test rig using cylindrical roller thrust bearings made of martensitic 100Cr6 steel. The resulting WECs were investigated with several characterisation techniques. Ultrasonic measurements showed the WEC were mainly located in the region of the overrolled surface in which negative slip occurs, which agrees with hypotheses based on an energetic approach for a prognosis. SEM orientation contrast imaging of the area around WEC revealed an inhomogeneous structure with varied grain sizes and a large amount of defects. Microstructure characterization around the WEA using EBSD showed significant grain refinement. Atom probe tomography showed the microstructure in the undamaged zone has a plate-like martensitic structure with carbides, while no carbides were detected in the WEA where the microstructure consisted of equiaxed 10 nm grains. A three dimensional characterisation of WEC network was successfully demonstrated with X-ray computerized tomography, showing crack interaction with unidentified inclusion-like particles.

Accurate predictions of fluid properties, such as density, oil formation volume factor and bubble point pressure, are essentials for all reservoir engineering calculations. In this paper, an approach based on nonlinear system identification modeling; Nonlinear ARX (NARX) and Hammerstein-Wiener (HW) predictive model, is proposed for forecasting the pressure/volume/temperature (PVT) properties of crude oil systems. To this end, two datasets; one containing 168 PVT samples from different Iranian oil reservoirs and other a databank containing 755 data from various geographical locations, were employed to construct (i.e. train) and evaluate (i.e. test) the models. Simulation results demonstrate that the proposed NARX and HW models outperform previously employed methods including three types of artificial neural networks models (committee machine, multilayer perceptron and radial basis function), two types of ANFIS models (grid partition and fuzzy c-mean) and several empirical correlations with the smallest prediction error, and that they are reliable models for predicting the oil properties in reservoirs engineering among other soft computing approaches.

A set L ź V of a graph G = ( V , E ) is a liar's dominating set if (1) for every vertex u ź V , | N u ź L | ź 2 and (2) for every pair u , v ź V of distinct vertices, | ( N u ź N v ) ź L | ź 3 . In this paper, we first provide a characterization of graphs G with γ L R ( G ) = | V | as well as the trees T with γ L R ( T ) = | V | - 1 . Then we present some bounds on the liar's domination number, especially an upper bound for the ratio between the liar's domination number and the double domination number is established for connected graphs with girth at least five. Finally, we determine the exact value of the liar's domination number for the complete r -partite graphs.

Nickel layers with 〈100〉, 〈210〉, 〈110〉 and 〈211〉 fiber textures were electrodeposited from additive-free Watts type electrolytes by adjusting both the pH and the applied current density. Quantitative crystallographic texture analysis by XRD was supplemented by micro-texture analysis applying EBSD. While XRD results correspond to absorption-weighted averages over the top part of the layer, EBSD on the cross section allowed studying the texture evolution as a function of distance to the substrate. Although layer growth started on amorphous substrates, implying that nucleation occurs unbiased by the substrate, often relatively strong fiber textures develop already at the early stage of growth. These fiber textures can further develop into other preferred fiber axis further away from the substrate. The experimental results demonstrate that already in an early stage of deposition there are major differences in the developing textures. The evolution of the substrate-adjacent textures into the texture of thick layers depends strongly on the deposition conditions.

A series of nickel layers was electrodeposited at different current densities from a Watts type electrolyte containing the additive 2-butyne-1,4-diol in various concentrations. The internal structure of the nickel electrodeposits was systematically investigated applying complementary microscopic and diffraction based characterization methods involving both surface and cross section investigations with different resolution and statistics. The complementary information gathered from combining the various techniques of microstructure characterization, in particular, supported the investigation of twins and the preferred crystallographic orientations of grains in the electrodeposits. Additive-free deposition results in relatively large columnar grains with numerous growth twins of nanoscale dimensions. The presence of the additive in the electrolyte yields considerable grain refinement already at low additive concentration, but the preferred crystallographic orientation of grains changes gradually with increasing additive concentration and twins with nanoscale dimensions are detected also in these samples.

This paper contributes to research on inter-organizational relationship dynamics by applying a dialectical approach. We analyze a situation where the relationship parties have divergent understandings of business exchange, and use a longitudinal, in-depth single case study method to investigate their interaction process. The case study focuses on the relationship between a customer and a supplier in the ferrochrome industry, using the acquisition of the supplier as the trigger of the relationship change process. The paper contributes to studies on relationship dynamics by showing how dynamics of inter-organizational relationships may result from struggles when parties’ interests and goals do not align with existing relationship arrangements. In particular, we focus on the process of (re)construction of the relationship and its linkage to the structural properties of the relationship.

Here we describe preparation and characterization of a series of nanocomposite polyelectrolytes based on partially sulfonated poly (ether ether ketone) (SPEEK) and organically modified montmorillonite (MMT). Optimum degree of sulfonation for SPEEK is selected based on its transport properties. MMT is modified via ion exchange reaction using a 2-acrylamido-2-methylpropanesulfonic acid (AMPS) as a functional modifier. AMPS-MMT at different loadings is introduced into the SPEEK matrices via the solution intercalation technique. Also, the nanocomposite membranes are fabricated using SPEEK and commercially available nanoclays like Cloisite Na (Na-MMT) and Cloisite 15A. Transport properties, proton conductivity and methanol permeability of the fabricated composite membranes are evaluated. Presence of AMPS-MMT significantly decreases the activation energy needed for proton conductivity. A membrane based on SPEEK/AMPS-MMT-3 wt% is selected as an optimum formulation which exhibits a high selectivity and power density at the elevated methanol concentrations. Moreover, it is found that the optimum nanocomposite membrane not only provides higher power output compared to the neat SPEEK and Nafion 117 membranes, but also exhibits a higher open circuit voltage (OCV) in comparison with pristine SPEEK and commercial Nafion 117 membranes. Owing to the desirable transport and electrochemical properties SPEEK/AMPS-MMT nanocomposite can be considered as an alternative membrane for direct methanol fuel cell applications. Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

The increasing scarcity of water for irrigation is becoming the most important problem for producing forage in all arid and semi-arid regions. Pearl millet is a key crop in these regions which needs relatively less water than other crops. In this research, a field study was conducted to identify the best combination of irrigation and nitrogen (N) management to achieve acceptable pearl millet forage both in quantity and quality aspects. Pearl millet was subjected to four irrigation treatments with interaction of N fertilizer (0, 75, 150 and 225 kg ha−1). The irrigation treatments were 40%, 60%, 80% and 100% of total available soil water (I40, I60, I80 and I100, respectively). The results showed that increasing moisture stress (from I40 to I100) resulted in progressively less total dry matter (TDM), leaf area index (LAI), and nitrogen utilization efficiency (NUzE), while water use efficiency (WUE) and the percentage of crude protein (CP%) increased. The highest TDM and LAI were found to be 21.45 t ha−1 and 8.65, in I40 treatment, respectively. TDM, WUE, CP% and profit responses to N rates were positive. The maximum WUE of 4.19 kg DM/m3 was achieved at I100 with 150 kg N ha−1. The results of this research indicate that the maximum profit of forage production was obtained in plots which were fully irrigated (I40) and received 225 kg N ha−1. However, in the situation which water is often limited and not available, application of 150 kg N ha−1 can produce high forage quality and guaranty acceptable benefits for farmers.

In this study plasma nitriding is applied on nickel–aluminum composite coating, deposited on steel substrate. Ni–Al composite layers were fabricated by electro-deposition process in Watt’s bath containing Al particles. Electrodeposited specimens were subjected to plasma atmosphere comprising of N2–20% H2, at 500 °C, for 5 h. The surface morphology investigated, using a scanning electron microscope (SEM) and the surface roughness was measured by use of contact method. Chemical composition was analyzed by X-ray fluorescence spectroscopy and formation of AlN phase was confirmed by X-ray diffraction. The corrosion resistance of composite coatings was measured by potentiodynamic polarization in 3.5% NaCl solution. The obtained results show that plasma nitriding process leads to an increase in microhardness and corrosion resistance, simultaneously.

Nickel-tungsten with satisfactory corrosion properties is a promising alloy to replace hard chromium. Relatively high adhesion between copper substrate and electrodeposited Ni-W alloy results in patterned morphology due to crack formation. In this work, corrosion resistance of patterned Ni-W alloys comprising 0-26 at.%.W were studied by potentiodynamic polarization and EIS in a medium containing Cl-. It is shown that corrosion resistance of single phase Ni-W is superior to amorphous and dual phase coated layers. It is also found that crack density is the dominant affecting factor on corrosion resistance of amorphous Ni-W alloys. (C) 2008 Elsevier Ltd. All rights reserved.

A highly efficient method for oxidative aromatization of Hantzsch 1,4-dihydropyridines in the presence of a catalytic amount of Mn(pbdo) 2 Cl 2 /MCM-41(Manganese (II) complex with 2,2′ bipyridine, 1,1′ dioxide (bpdo) ligand immobilized within nanoreactors of MCM-41) or Mn(pbdo) 2 Cl 2 /Al-MCM-41 as reusable, green and heterogeneous catalysts in refluxing acetic acid is reported.

The three-component one-pot synthesis of 2-amino-5-oxo-dihydropyrano[3,2- c ]chromene derivatives by condensing 4-hydroxycoumarin, aldehydes and alkylnitriles using a catalytic amount of H 6 P 2 W 18 O 62 · 18H 2 O in aqueous ethanol under heating conditions is reported.

The cementation of cadmium ions by zinc powder was studied in a batch reactor at low and high concentrations at pH 5.2–5.4 and it is shown that the reaction is first-order. XRD and SEM analysis confirm that the deposited layer is metallic with no evidence of basic zinc sulphate or re-dissolution of cadmium. Dependence of the reaction constant on initial cadmium concentration proves the reaction mechanism. Different possible kinetic controlling models of cadmium ion (Cd2+) cementation from aqueous solution by zinc powder were studied with respect to initial cadmium concentration, temperature, zinc powder size and stoichiometric ratio. The experiments demonstrate that at initial cadmium concentrations > 1000 ppm, the ash diffusion control model prevails, while at concentrations

A total dominating set of a graph G is a set S of vertices of G such that every vertex is adjacent to a vertex in S. The total domination number of G, denoted by γt(G), is the minimum cardinality of a total dominating set. Let G be a connected spanning subgraph of Ks,s and letH be the complement of G relative to Ks,s; that is, Ks,s = G⊕H . The graph G is k-supercritical relative to Ks,s if γt(G) = k and γt(G + e) = k − 2 for all e ∈ E(H). In Section 4 in [1], it is shown that the diameter of a 6-supercritical graph is 3, 4 or 5. Further 6-supercritical graphs with diameter 4 or 5 are characterized. As a concluding remark a construction of 6-supercritical graphs with diameter 3 is described. However this construction is incorrect. Here we provide a correct construction. Following the notation in [1], if all edges between two independent sets X and Y are present, we say that [X, Y ] is full. For k ≥ 3, let Gk be the graph with vertex set A ∪ B ∪ C ∪ D ∪ {x, y}, where A = {a1, a2, . . . , ak}, B = {b1, b2, . . . , bk}, C = {c1, c2, . . . , ck} and D = {d1, d2, . . . , dk}, and with edge set E(Gk) = {xai | i = 1, 2, . . . , k} ∪ {ydi | i = 1, 2, . . . , k}∪{aibj | 1 ≤ i, j ≤ k, i ≠ j}∪{bicj | 1 ≤ i, j ≤ k, i ≠ j}∪{cidj | 1 ≤ i, j ≤ k, i ≠ j}∪{aidi | i = 1, 2, . . . , k}∪{xy}. Thus, [{x}, A] and [{y},D] are full, each of [A, B], [B, C] and [C,D] is full minus a perfect matching, while [A,D] consists of a perfect matching. The graph Gk is a 6-supercritical graph with diameter 3.