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The purpose is to focus on improving the water or metal ion uptake of modified cellulose.

Grafting copolymerisation of hydrophilic monomers such as acrylamide or hydrophobic monomers as acrylonitrile onto cotton linters was performed.

The grafting process has two advantages. The first is to replace the hydroxyl group of C₆ of the glucose units in the substrate by carboxyl group that attract the metal ions from the solution. The second is to decrease the number of the hydroxyl groups in the cotton linters so that the hydrogen bonding between the cotton linters strands decreases and so the crystallinity index of substrate decreases by introduction of this hydrophilic group so it becomes more chemically active.

Partial substitution of hydroxyl groups of cellulose by more hydrophilic ones via grafting reaction followed by alkaline hydrolysis was performed. The effects of different conditions such as temperature, time, initiator concentration, monomer concentration and kind of substrate were studied. The polymerisation per cent, grafting per cent, the grafting efficiency and the nitrogen per cent of the grafted samples were determined. The molecular structures of cotton linters, grafted cotton linters with acrylamide and its hydrolysis product were studied using infrared spectroscopy, which indicates the fixation of the monomers on the cotton linters. Sodium binding capacity and the metal ion uptake of some metal ions by the product were determined.

The water or metal ion uptake of the modified cellulose was improved.

The objective is to explore various adder architectures using different logic‐design styles and transistor‐sizes for different operand sizes. The scope of this work is the development of tools, which can be used to predict an optimum adder design for a given application based on the speed and energy‐consumption constraints.

The work has been carried out in two parts. In the first part, simulation results were generated using five different architectures; each designed using four logic design styles for three different transistor sizes. The designs were simulated to generate the values of worst‐case propagation delay and energy consumption per addition. This information is used for validating the delay and energy consumption per addition in the second part.

Optimum adder design under varying condition can be found out using this work.

The predictive model does not consider the variation in load capacitance of each cell.

At present, a prime requirement in application specific integrated circuit design is reduction in design cycle time. As a result, there is minimum scope for exploration of arithmetic units in order to choose the best‐suited design. This work will help the designers to choose an optimum adder design for a given set of requirements.

In this work, four degrees of freedom are taken in adder design space, which are not taken before. Here, the adder design space has been explored, studied, and analyzed in this study under so many varying conditions.

This paper presents a prediction on the impact of technology scaling on phase‐locked loop (PLL) performance behaviour. Power and maximum operating frequency of an Analogue PLL and a Type II phase‐frequency detector (PFD)‐based PLL from which the behaviours of other PLLs derived from the two architectures can be estimated, are analysed and their future behaviours as a function of technology are predicted.

Analogue models were developed and Mentor Graphics VHDL‐AMS mixed‐signal simulations were performed on the two PLL architectures. Behavioural power and frequency equations as a function of technology were derived based on thorough data and graphical analyses.

A prediction of PLL frequency and power dissipation as a function of technology for two main PLL architectures.

The parameters in each equation derived should include other contributing factors as well as other design approaches such as multi‐VDD, multi‐Vth, etc. future work should also include prediction of jitter and phase noise for the two main PLL topologies.

This paper is of high significance in PLL design. The predicted equations could be used to reduce a major portion of a PLL designers' design time when choosing a PLL topology, and help them predict the impact of technology on the performance of the chosen architecture.

This paper aims to model and analyze Jeffery Hamel’s channel flow with the magnetohydrodynamics second-grade hybrid nanofluid. Considering the importance of studying the velocity slip and temperature jump in the boundary conditions of the flow, which leads to results close to reality, this paper intends to analyze the mentioned topic in the convergent and divergent channels that have significant applications.

The examination is conducted on a EG-H_2 O <30%–70%> base fluid that contains hybrid nanoparticles (i.e. SWCNT-MWCNT). To ensure comprehensive results, this study also considers the effects of thermal radiation, thermal sink/source, rotating convergent-divergent channels and magnetic fields. Initially, the governing equations are formulated in cylindrical coordinates and then simplified to ordinary differential equations through appropriate transformations. These equations are solved using the Explicit Runge–Kutta numerical method, and the results are compared with previous studies for validation.

After the validation, the effect of the governing parameters on the temperature and velocity of the second-grade hybrid nanofluid has been investigated by means of various and comprehensive contours. In the following, the issue of entropy generation and its related graphical results for this problem is presented. The mentioned contours and graphs accurately display the influence of problem parameters, including velocity slip and temperature jump. Besides, when thermal radiation is introduced (Rd = +0.1 and Rd = +0.2), entropy generation in convergent-divergent channels decreases by 7% and 14%, respectively, compared to conditions without thermal radiation (Rd = 0). Conversely, increasing the thermal sink/source from 0 to 4 leads to an 8% increase in entropy generation at Q = 2 and a 17% increase at Q = 4 in both types of channels. The details of the analysis of contours and the entropy generation results are fully mentioned in the body of the paper.

There are many studies on convergent and divergent channels, but this study comprehensively investigates the effects of velocity slip and temperature jump and certainly, this geometry with the specifications presented in this paper has not been explored before. Among the other distinctive features of this paper compared to previous works, the authors can mention the presentation of velocity and temperature results in the form of contours, which makes the physical analysis of the problem simpler.

Computational speed and robustness of the coupled (MEDICI) and decoupled (TRASIM) method based simulators are compared. Transient and steady‐state avalanche simulations are presented. The decoupled method shows significantly lower memory requirements, higher robustness and up to 30 times higher speed.

Enhanced efficiency of the proposed modification of the Gummel decoupled method enables significant reduction of memory requirements in comparison to the conventionally used Newton‐like methods with approximately equal CPU time expense. For 10,000 mesh nodes it only requires 4.4 Mbytes of virtual memory (compare to 62 Mbytes for PISCES‐2B). The method exhibits good stability and convergence rate and has significant advantages compared to the other often used half‐implicit scheme. Low memory requirements and efficiency make the method attractive for future 3‐D applications.

This research conducted two experiments to understand the performance (correctness and efficiency) of novice database designers, and perceptions of ease of use and preferences of two approaches for modeling relational databases: the semantic‐oriented approach (top‐down, e.g. using the entity‐relationship model) and the logical‐oriented approach (bottom‐up, view decomposition, focusing only on the logical model). The findings indicated that in experiment 1, semantic‐oriented treatments performed better in a complex, written‐text case; logical‐oriented treatments were better in a simple, tabular‐form case. The same situation happened in experiment 2 though the differences were not statistically significant.

Modern slavery is a significant issue addressed in the United Nations’ Sustainable Development Goals. In 2015, the UK Government introduced the Modern Slavery Act as part of a crucial broader set of initiatives that aimed to attack modern slavery. Regardless of the initiatives taken to mitigate this risk, little is known about how modern slavery disclosure affects corporate financial performance (CFP). Hence, our study aims to examine the impact of MSD on CFP empirically. It also examines the moderating role of governance quality on the MSD–CFP nexus.

We use computer-based content analysis to assess MSD levels for a sample of non-financial companies' annual reports. We use regression analysis to test our research hypotheses for a sample period of 2013–2019 for Financial Times Stock Exchange (FTSE) All-Share non-financial UK firms. Our sample consisted of 786 observations.

We provide new empirical evidence that externally communicating modern slavery information in annual report narratives is associated with CFP. The finding is in line with stakeholder theory, which states that engaging in social responsibility practices and responding favourably to the stakeholders’ interests and desires would enhance corporations’ reputation and ultimately improve their performance. We further highlight the role of governance quality in this nexus and find that the interaction between governance quality and MSD is negative, suggesting a replacement effect.

Our findings can be of interest to government, policymakers and other stakeholders. Policymakers need to establish a new, broader set of enforcement arrangements for MSD that may lead to better CFP.

Our research idea is original as it links emerging global issues (e.g. MSD) with traditional corporate concerns (financial performance) in a way that is likely to provide new insights as well as managerial and policy implications.

This study uses a phenomenology method to investigate the experiences of married Muslim women while having romantic conversations via online dating sites during the COVID-19 pandemic. Sixteen participants were selected via purposive sampling, and the data were gathered through semi-structured interviews. The results confirm that resistance to Islamic marriage limitations is the underlying reason accounting for Muslim women's romantic chat. However, “premarital experiences in virtual space” and “chat as a remedy for loneliness” create the causal conditions of romantic chat, and “experience of family restrictions” and a “sense of freedom” provides the foundation for an online romantic chat. It is worth noting that those who voice a sense of “unhappy marriage” and “husband's sexual coldness” are more likely to turn to sex chat during the COVID-19 pandemic. The consequences of digital romantic conversations for married Muslim women are “chat addiction” and “feeling a sense of betrayal.”

This paper presents a database system developed to provide a computerized environment for requirement management during the product definition phase. The scope of this database system is to facilitate and demonstrate a methodology for product definition by recognizing and adopting functional requirement patterns from previous product designs so as to address a broad spectrum of domain‐specific customer requirements and organize requirement information for product specifications. The database system improves the product definition process during design and redesign efforts by integrating customer and design information all together and by reusing this information. A prototype requirement management database system is implemented on a PC platform using Microsoft Access.