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Built upon theories from outside the construction management literature, this study assesses the impact of product diversification on the performance of construction firms in the UK. Performance was measured based on financial ratios of management performance while diversification was measured by the specialisation ratio. The research involved the use of financial data of construction firms covering the period 1995‐2004. The choice of the period is informed by the economic stability during the period and also, by the fact that diversification is a long‐term strategy. The findings indicate that focused firms outperform both moderately and highly diversified firms based on return on total assets (ROTA) and profit margin (PM). However, no performance difference was found between the moderately diversified and highly diversified firms.

This paper aims to focus on the preparation of a cation exchange filament for three-dimensional (3D) fused deposition modeling (FDM). The polymeric binder was mixed with the selected conventional cation exchange resin and a filament was prepared using a mini extruder. Filaments were tested by mechanical properties, chemical properties, quality and melt flow index. Samples were prepared from granulate using a press, which were tested for electrochemical properties, thermal properties. The best result of ion exchange capacity (IEC) up to 3.0 meq/g of the dry matter was achieved with filament fill 65%. Permselectivity results above 90% were determined for 55%–65% filling of the cation exchanger. The results obtained are a promising step for the preparation of 3D printed cation exchange membranes (CEMs) with a defined structure.

The prepared granulates and filaments were evaluated using mechanical, rheological and thermal properties.

The prepared cation exchange filament can be used for the 3D printing process. The best result of IEC up to 3.0 meq/g of the dry matter was achieved with filament fill 65%. Permselectivity results above 90% were determined for 55%–65% filling of the cation exchanger, and area resistances 3.0 Ocm² and specific resistances around 57 Ocm for 65% filling of the cation exchanger. The results obtained are a promising step for the preparation of 3D printed CEMs with a defined structure.

The prepared cation exchange filament. Using new materials for 3D print of cation exchange membrane. Production without waste. The possibility of producing 3D membranes with a precisely defined structure. Processing prepared filaments using a cheap FDM 3D printing method. New direction of membrane formation.

Building on the entrepreneurship, marketing and strategic management literature, we propose a conceptual model to investigate the effects of entrepreneurial strategic posture (ESP), perceived environmental uncertainty and international diversifi cation strategy on performance. The ESP‐International diversification‐Performance relationship is investigated using a contingency framework. Entrepreneurial strategic posture is postulated to influence the use of international diversifi cation strategy of entrepreneurial fi rms. Moreover, perceived environmental uncertainty is hypothesized to strengthen the relationship between a firm’s entrepreneurial strategic posture and international diversification strategy, which ultimately affect the firm’s performance. Propositions for further empirical studies are provided in addition to managerial and theoretical contributions.

We assess the impact of NZ IAS 32 on the financial reporting of convertible financial instruments by retrospective application of the standard to a sample of New Zealand companies over the period 1988 ‐ 2003. NZ IAS 32 has a broader definition of liabilities than does the corresponding current standard (FRS‐31) and it does not permit convertibles to be reported under headings that are intermediate to debt and equity. The results of the study indicate that in comparison with the reported financial position and performance, the reporting of convertibles in accordance with NZ IAS 32 would result in higher amounts for liabilities and higher interest. Thus, analysts using financial statement information to assess risk of financial distress will need to revise the critical values of commonly used measures of risk and performance when companies report under NZ IAS

The purpose of this paper is to investigate the inhibition effect of 2‐aminoethane thiol hydrochloride, 2‐cystamine dihydrochloride, 2,3‐dimercapto‐1‐propanol, 1,2‐ethanedithiol, and the synergistic effect of these compounds with halide ions (Cl⁻, Br⁻, I⁻) and with some metal cations (Co^2 +, Ni^2 +, Cu^2 +, Zn^2 +).

The inhibiting effect of the studied thiols on the corrosion of carbon steel in 0.5 M H₂SO₄ solution were investigated using potentiodynamic polarisation, electrochemical impedance spectroscopy and linear polarisation methods.

The inhibition action of thiols depends mainly on the type of the heteroatom present in the inhibitor molecule. The increase in inhibition efficiencies with increase in inhibitor concentration revealed that the studied compounds were adsorbed onto steel surfaces and the adsorption mechanism obeyed the Langmuir adsorption isotherm. Polarisation curves indicated that thiols containing both N and S atoms in their structure behaved as mixed type inhibitors, while thiols containing only an S atom in their structure acted essentially as anodic inhibitors. The increase in the inhibition efficiencies of thiols with the addition of halide ions indicates that halides play important role in the adsorption process. The synergistic effect of the studied metal cations could be explained by the adsorption of complex ions formed from thiol molecules and metal cations.

This paper provides useful information about the relationship between inhibition efficiencies and the structures of thiols and clarifies the mechanism of the synergistic effects of some halides and some metal cations.

The study aims to focus on the preparation of a heterogeneous cation exchange membrane by a three-dimensional (3D) method – fused filament fabrication using a series of nozzles of various diameters (0.4–1.0 mm). Polypropylene random copolymer (PPR) as a polymeric binder was mixed with 50 Wt.% of the selected conventional cation exchange resin, and a filament was prepared using a single screw mini extruder. Then filament was processed by FFF into the membranes with a defined 3D structure.

Electrochemical properties, morphology, mechanical properties and water absorption properties were tested.

Dependence of the tested properties on the used nozzle diameter was found. Both areal and specific resistances increased with increasing nozzle diameter. The same trend was also found for permselectivity. The optimal membrane with permselectivity above 90%, areal resistance of 8 O.cm² and specific resistance of 124 O.cm² was created using a nozzle diameter of 0.4 mm.

Using new materials for 3D print of cation exchange membrane with production without waste. The possibility of producing 3D membranes with a precisely defined structure and using a cheap 3D printing method. New direction of membrane structure formation. 3D-printed heterogeneous cation exchange membranes were prepared, which can compete with commercial membranes produced by conventional technologies. 3D-printed heterogeneous cation exchange membranes were prepared, which can compete with commercial membranes produced by conventional technologies.

This research aimed at identifying the most significant risks relevant to construction contracts of two power station projects in Egypt. These were large scale, fast‐track projects where a multi‐package contracting plan was utilized. Further, the study investigated how risks were perceived and managed by a large sample of Egyptian and international contractors who participated in the execution of these two major projects. A checklist of risk categories was developed to aid contractors in their risk identification effort. The compilation of this checklist identified the following risk categories: 1) owner’s obligations; 2) interface with other contractors; 3) liability risks; 4) financial risks; 5) risks related to changes; 6) technical risks and 7) consortium risks. Research results identified a marked lack of consistency in the contractors’ risk identification effort. Contractors possessing past experience in Egypt were far better able to identify the relevant risks. On the other hand, local Egyptian contractors with vast experience in Egypt but limited project management experience were shown to lack the necessary expertise to properly identify risks and to take the appropriate exceptions. Furthermore, the results revealed that bidders do not include in their proposals their “true” lists of exceptions which represent genuine risks to them.

Aluminum phosphate is useful catalyst for many reactions. There are a lot of reports about catalytic activities of aluminum phosphate, however little reports about the relationship among the preparation, composition, catalytic activity of this phosphate. Phosphates transform to various other phosphates with hydrolysis and dehydration reactions by heating. In this work, some aluminum orthophosphates and condensed phosphates were prepared, and their compositions were estimated. Furthermore, specific surface area, acid strength, the amount of acidic sites, and the catalytic activities for the decomposition of trifluoromethane of these salts were investigated. Aluminum ortho‐ and polyphosphates were prepared in the systems of ortho‐ and poly‐phosphates. The catalytic activity for decomposition of CHF3 was related with a certain degree of specific surface area, acid strength, and the amount of acidic sites. Aluminum orthophosphate with a small amount of sodium cation had higher catalytic activity at lower temperature.

Bisphosphonate (BP) medications can be applied to prohibit the damage of bone density and the remedy of bone illnesses such as osteoporosis. As the metal chelating of phosphonate groups are nearby large with six O atoms possessing the high negative charge, these compounds are active toward producing the chelated complexes through drug design method. BP agents have attracted much attention for the clinical treatment of some skeletal diseases depicted by enhancing of osteoclast-mediated bone resorption.

In this work, it has been accomplished the CAM-B3LYP/6–311+G(d, p)/LANL2DZ to estimate the susceptibility of SWCNT for adsorbing alendronate, ibandronate, neridronate and pamidronate chelated to two metal cations of 2Mg²⁺, 2Ca²⁺, 2Sr²⁺ through nuclear magnetic resonance and thermodynamic parameters. Therefore, the data has explained that the feasibility of using SWCNT and BP agents becomes the norm in metal chelating of drug delivery system which has been selected through alendronate → 2X, ibandronate → 2X, neridronate → 2X and pamidronate → 2X (X = Mg²⁺/Ca²⁺/Sr²⁺) complexes.

The thermodynamic results have exhibited that the substitution of 2Ca²⁺ cation by 2Sr²⁺ cation in the structure of bioactive glasses can be efficient for treating vertebral complex fractures. However, it has been observed the most fluctuation in the Gibbs free energy for BPs → 2Sr²⁺ at 300 K. Furthermore, Monte Carlo simulation has resulted by increasing the dielectric constant in the aqueous medium can enhance the stability and efficiency of BP drugs for preventing the loss of bone density and treating the osteoporosis.

According to this research, by incorporation of chelated 2Mg²⁺, 2Ca²⁺ and 2Sr²⁺ cations to BP drugs adsorbed onto (5, 5) armchair SWCNT, the network compaction would increase owing to the larger atomic radius of Sr²⁺ cation rather than Ca²⁺ and Mg²⁺, respectively.

The specific influence of calcium and sodium cations on the rate of deposition of a‐Fe2O3 (a main corrosion product in boilers and heat exchangers) has been experimentally studied. A deposition model based on the microlayer evaporation and dryout phenomena that occur in the nucleate boiling bubble is put forward for interpretation of the deposited layer. It has been found that the rate of deposition of Fe2O3 increases with the increase in valency of the soluble cations. With calcium, the deposition rate increases linearly with the increase in its ionic concentration, whereby the rate is increased by 5.9, 6.8 and 7.6 with 200, 400 and 600 ppm calcium respectively. Development of the deposition layer takes place in the valleys of the surface contour according to a micro‐layer evaporation mechanism. Successive deposition is performed at the periphery of the first deposit. Reduction in cation content in the crude solution and selecting smooth heated surfaces are recommended to reduce the ∝‐Fe2O3 deposition on heated surfaces in boiling water.