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The purpose of this paper is to show how to remove some dyestuffs, as pollutants, from their aqueous solutions.

To achieve the goal, a water soluble hyperbranched poly (ester‐amide) (HBP) was synthesised using the melt polycondensation method by the reaction of maleic anhydride (MA) and diisopropanol amine (DIPA) at 140°C at a molar ratio of 1:1.3 MA: DIPA, respectively. This HBP was incorporated in the preparation of an effective microcrystalline cellulose (MCC)/dimethyloldihydroxyethylene urea (DMDHEU)/HBP adduct by crosslinking HBP with DMDHEU in presence of MCC. Furthermore, the prepared adduct was characterised by investigation its infra red and then utilised in the removal of three anionic dyestuffs from aqueous solutions, namely Irgalan Blau 3GL (an acid dye), SIRIUS Blau S‐BRR (a direct dye) and Levafix Brill Orange P‐GR (a hydrolysed reactive dye).

The results obtained revealed that the optimum conditions for preparing MCC/DMDHEU/HBP adduct are [HBP], 90 g/l; [DMDHEU], 200 g/l; LR, 1/3.3; [NC₄LH], 20 g/l; a time of 30 min and a temperature of 160°C. Moreover, the results also showed that the extent of removal of such dyestuffs from their aqueous solutions by the prepared adduct follows the order: reactive dye>acid dye>direct dye, it is more pronounced at lower than at higher pH values and the removal of each dye by that adduct follows a first‐order reaction.

Other substrates such as chitosan can be used to prepare more effective adducts.

Hyperbranched polymers can be used effectively to prepare ion exchangers capable of removing the pollutants of dyestuffs from their aqueous solutions.

The aforementioned prepared HBP is a novel hyperbranched polymer and could be applied in the removal of many other pollutants.

This paper aims at building a discharge model for the power cable bellows based on plasma energy deposition and analyzing the discharge ablation problem.

Aiming at the multiphysical mechanism of the discharge ablation process, a multiphysical field model based on plasma energy deposition is established to analyze the discharge characteristics of the power cable bellows. The electrostatic field, plasma characteristics, energy deposition and temperature field are analyzed. The discharge experiment is also carried out for result validation.

The physical mechanism of the bellows ablative effect caused by partial discharge is studied. The results show that the electric field intensity between the aluminum sheath and the buffer layer easily exceeds the pressure resistance value of air breakdown. On the plasma surface of the buffer layer, the electron density is about 4 × 1,019/m³, and the average temperature of electrons is about 3.5 eV. The energy deposition analysis using the Monte Carlo method shows that the electron range in the plasma is very short. The release will complete within 10 nm, and it only takes 0.1 s to increase the maximum temperature of the buffer layer to more than 1,000 K, thus causing various thermal effects.

Its physical process involves the distortion of electric field, formation of plasma, energy deposition of electrons, and abrupt change of temperature field.

The purpose of this paper is to investigate and compare the influence of end-effect on the torque-speed characteristics of three conventional switched flux permanent magnet (SFPM) machines having different stator/rotor pole combinations, i.e. 12/10, 12/13 and 12/14 as well as three novel topologies with less permanent magnets (PMs), i.e. multi-tooth, E-core and C-core.

SFPM machines combine the advantages of simple and robust rotor and easy management of the temperature due to the location of the PMs and armature windings on the stator. However, due to spoke location of the PMs a large flux leakage in the end region, i.e. end-effect, can be observed which could result in a large reduction in the electromagnetic performance. Therefore, the influence of end-effect on the torque-speed characteristics is investigated. 3D-finite element analyses (FEA) results are compared with their 2D-FEA counterparts in order to account for the end-effect influence.

It has been concluded that due to end flux leakage, lower torque capability in the constant torque region is observed in the six machines. However, improved flux-weakening capability in the conventional machines can be exhibited at high current levels, whereas due to the large inductance lower power capability in the multi-tooth, E-core and C-core machines is obtained.

The influence of temperature rise on the performance is not included.

This paper has analysed the influence of end-effect on the torque-speed characteristics of several SFPM machines.

Electrochemical measurements were used to characterize the inhibiting effectiveness of Curcuma and saffron, considered as green inhibitors in a corrosive environment 3% NaCl on A106 Gr B carbon steel.

This study/paper aims to polarization and potentiodynamic impedance spectroscopy techniques were performed on A106 Gr B carbon steel in the 3% NaCl environment only and containing various concentrations of Curcuma and Saffron (0.005, 0.01, 0.02, 0.04, g/L) after 30 min of immersion; these measures were taken at a temperature of (298 ± 1)K. A voltlab PGZ 301 assembled by A 106 Gr B carbon steel working electrode, a platinum counter electrode (CE) and a saturated calomel electrode as the reference electrode were used in the experiment. In this research, potentiodynamic polarization and electrochemical impedance spectroscopy were used.

The inhibition efficiencies increased with increase in the concentrations of the inhibitor but decreased with rise in temperature. The obtained results show an optimal efficiency with 0.04 g/L which are ordered of 78 and 96 per cent successively for the two inhibitors. Curcuma and saffron acts as a mixed type inhibitor. Adsorption of the inhibitor molecules corresponds to Langmuir adsorption isotherm. Mechanism of inhibition was also investigated by calculating the thermodynamic and activation parameters like (ΔG), (E_a), (ΔH_a) and (ΔS_a). The inhibitor molecules followed physical adsorption on the surface of carbon steel.

The present trend in research on environmental friendly corrosion inhibitors is concentrating on products of natural origin due principally to non-toxicity and eco-friendliness. Among these natural products are curcuma and saffron.

The purpose of this study was threefold: to trace the extent to which digital transformation strategies are being implemented in organizations; to statistically measure, validate, predict and examine how digital leaders perceive a synthesized digital transformation model (DTM); and to explore whether leaders with different demographic characteristics perceive the DTM similarly.

The study authors surveyed 778 leaders/managers from the United Arab Emirates (UAE) to assess the synthetized DTM consisting of four dimensions and nine perception constructs that represent how leaders manage employees in a digital environment. The survey questions were adapted from the 2014 Westerman leading digital book published in Harvard business press.

The general findings revealed that UAE organizations that were already in the digital transformation stage before COVID-19 reacted and responded extremely quickly to speed up the implementation of their respective digital transformation strategies. We concluded that our proposed and synthetized DTM is valid and predictable, and can be adapted to trace the stages of digital transformation by leaders. A positive relationship was found between the DTM’s four dimensions and their related constructs as perceived by the leaders, regardless of differences in their demographic characteristics.

The synthesized digital transformation model is unique in that the authors believe there is no other research that purports to synthesize, validate and correlate using the digital transformation campus dimensions and its related constructs, reflecting leaders' perceptions toward adopting this campus. As well, this is the first UAE study to explore and compare the perspectives of leaders on their digital practices after COVID-19 in a country that has an established IT infrastructure.

This study establishes the principles and process steps of a new basic trousers pattern using measurements obtained according to the rules of the anthropometric measurement system. The newly developed pattern-making system in this study will be called the “Anthropometric Measurements Based Pattern Making System” (AnMePa). It is aimed at producing trousers that are more fitting to the body, thanks to this pattern-making system.

In this research, four pattern-making systems used in many parts of the world were compared with the “Anthropometric Measurements Based Pattern Making System” (AnMePa) with regard to the overall appearance and body fit of trousers prepared according to these systems. 10 virtual mannequins (VM) with different adult female body measurements were created, and trousers patterns were prepared for these mannequins. The trousers’ patterns were made and dressed on the mannequins in a 3D virtual dressing system. The body fit of the virtual garments was evaluated by five experts. The scores given by the experts were evaluated using the fuzzy logic method.

According to the results, it is seen that the new basic trousers pattern developed by utilizing the anthropometric measurement system, AnMePa, provides the best body fit among the basic trousers patterns created according to the other examined pattern-making systems. The combination of 3D virtual dressing and fuzzy logic in the evaluation of garment body fit is considered an innovative method for the future of fashion design and production.

In the developed AnMePa, unlike the existing pattern-making systems, values that can be associated with the body measurements of individuals in a way that could be suitable for each community were used instead of constant values in the pattern-making process. Furthermore, the integration of 3D virtual fitting and fuzzy logic in assessing garment fit is considered a pioneering approach with significant implications for the future landscape of fashion design and production.

The purpose of this paper is to present the entropy analysis of ferrofluid inside a porous space with magnetic force. Homogenous model with second law analysis is also taken into account.

Innovative model has been proposed and designed using control volume finite element method.

Experimental results demonstrate that Bejan number augments with augment of Rayleigh. As Hartmann number rises, exergy loss enhances. Exergy loss increases by increasing Hartmann number, whereas magnetic entropy generation reduces with the decrease of Ha. The proposed model can be used for combustion process and optimizing the performance of energy conversion system like gas turbine.

To the best of authors’ knowledge, this model is reported for the first time.

The purpose of this study aims to simulate the long-period fiber grating sensor pulse peak position against the transmission range. The long-period fiber grating sensor pulse peak position against the transmission range is simulated clearly where the pulse peak value at zero position is 0.972655 with the ripple factor of unity. It is demonstrated that the long-period fiber grating sensor bandwidth can be estimated to be 50 µm. Wavelength shift of the long-period grating sensor (LPGS) is reported against grating wavelength, applied temperatures and applied micro strain.

This work has reported the numerical simulation of LPGS transmission spectrum behavior characteristics under the strain and temperature effects by using OptiGrating simulation software. The sensor fabrication material is silica-doped germanium. The transmittivity/reflectivity and input spectrum pulse intensity of long-period Bragg sensor variations are simulated against the grating wavelength variations. Input/output pulse intensity of LPGS variations is simulated against the timespan variations with the Gaussian input pulse from 100 to 500 km link length.

Temperature variation and strain variation of the LPGS are outlined against both applied temperatures and micro-strain variations at the central grating wavelength of 1,550 nm.

It is demonstrated that the long period fiber grating sensor bandwidth can be estimated to be 50 µm. Wavelength shift of the long period grating sensor is reported against both grating wavelength, applied temperatures and applied micro strain. Temperature variation and strain variation of the long period grating sensor are outlined against both applied temperatures and micro strain variations at the central grating wavelength of 1550 nm.

In this work, the thermoelastic response in a micro-stretch thermoelastic half-space submerged in an unlimited non-viscous fluid under gravity, the medium is studied using the three-phase-lag model (3PHL) and Green-Naghdi theory (G-N III).

The normal mode analysis was the analytic technique used to obtain the exact formula of the physical quantities.

The magnesium crystal element is used as an application to compare the predictions induced by gravity on microstretch thermoelastic immersed in an infinite fluid of the three-phase-lag model with those for Green–Naghdi. Gravity has been noticed to have a major effect on all physical quantities. Comparisons were also made for three values of wave number and three values of the real part frequency.

This work is concerned with the thermoelastic micro-stretch solid immersed in an infinite and inviscid fluid and subjected to a gravitational field. The governing equations are formulated in the context of the 3PHL model and G-N theory. An analytical solution to the problem is obtained by employing normal mode analysis. Comparisons of the physical quantities are shown in figures to study the effects of gravity, wave number and the real part of the frequency.

The current status of nanotechnology research and development in Jordan is analyzed. In recent years, Jordanian institutions demonstrated considerable interest in the development and production of nanotechnology. Here the purpose of this paper is to provide detailed information about the status of nanotechnology in Jordan in terms of several factors that influence selectivity in nanotechnology and the number of published peer-reviewed research articles.

Several factors that influence selectivity in nanotechnology and the number of published peer-reviewed research articles were analyzed. A detailed analysis of the collected data reveals that the number of publications, citations, and patents is highly dependent on the amount of research fund.

The development in nanotechnology is associated with presence and accessibility of sensitive laboratory equipment. The nanotechnology research output in Jordan is still lower than it should be due to the lack of necessary laboratory infrastructure. This is due to the insufficient funds allocated to scientific research, the restrictive access to available instruments and the bureaucracy of some governmental departments. Compared to some developed countries, Jordan is noticeably behind in developing a nanotechnology system of research and industry. It will take time as well as technical and financial resources in order to achieve an advanced level in the field of nanotechnology in Jordan. Nevertheless, many Jordanian researchers are doing their best and are producing some good research articles.

The many applications to the same approach.

Time and publications’ resources.

Peer cooperation.

First comprehensive review ever. A base for researchers and decision makers.