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The behaviour of chemically modified cellulose towards dyeing is an interesting subject. Cellulose undergoes substantial changes in its chemical and physical properties by chemical modification. Some investigations were carried out to study the effect of these changes on dyeing and dyeing properties of cellulose. Previous reports have disclosed that the dyeability of chemically modified cellulose differs significantly when compared with the unmodified cellulose. Among the modified cellulose studied were partially acetylated cellulose, cyanoethylated cellulose, carboxymethylated cellulose, cellulose tiaocarbonate and cellulose copolymerized with various vinyl monomers.

In Bangladesh (BD), delays in infrastructure are common. Many previous studies have explored the causes of infrastructure delays. However, this study investigated the causes of delays by taking responses from the stakeholders who are responsible for planning, design, funding, approval and implementation. There are few studies that have related infrastructure project delays to heterogeneity in stakeholders’ perceptions.

A structural equation (SE) model is developed with 350 normally distributed data points to understand the heterogeneity in stakeholders’ perceptions regarding delays in infrastructure projects in BD. Additionally, the relative importance index (RII) approach is used to assess the responses, validating the SE model.

The study finds that among the three latent variables, “Project itself related delay” has more influence on delays in infrastructure projects. Among the observed variables under the “project itself related delay” latent variable, “DPP approval process” has the most significance. From the heterogeneity analysis, the study found differences in responses among the stakeholders from “the Engineering Department,” “the Planning Office” and “the Construction Firm/Industry.” An important class of stakeholders believes that their stage is not being delayed and that other stages require attention.

The data sample is 350. More data can improve the accuracy of the findings. Most of the respondents are civil engineers (74%) and represent the owner of the project. Sample data from more stakeholders’ will enhance the accuracy of the result.

This study addresses the requirements of Bangladeshi project stakeholders and how their interactions cause delays in projects. Furthermore, the opinions of other stakeholders are taken into consideration when determining the specific factors of individual stakeholders that are causing delays. Practically, the distance between stakeholders should be reduced. A project manager can play a role in this regard. Initiatives should be taken on how to complete the project quickly by eliminating the requirements discussed among the stakeholders and bureaucratic complications. Instead of placing blame on one another, stakeholders should take the initiative to figure out how to work together to finish the project on schedule. The Planning Commission’s approval of the Development Project Proposal (DPP) and Revised Development Project Proposal (RDPP) should be obtained as soon as possible by owner stakeholders. In order to avoid frequently changing the DPP, owners should also exercise greater caution when choosing contractors. Contractor stakeholders should use efficient and proper manpower and equipment so that unexpected delays are not created during the execution of work. Since the role of the contractor stakeholder is the most important among the three types of stakeholders, the contractor should raise awareness and urge the owners to get the RDPP approved quickly.

The findings from the study can help mitigate delays in infrastructure projects in BD, taking into account the perceptions of various stakeholders.

The removal of nickel and mercury from drinking water, using powdered activated carbon (PAC) and granular activated carbon (GAC) was studied intensively. The water studied was artificially contaminated by Ni and Hg to yield 2mg/l each. Both batch and continuous systems were tested. The time needed to maintain equilibrium and the adsorption isotherm were determined by the batch system. The results obtained were found to be confirmed with Freundlich’s equation, rather than Langmuir or BET. When the PAC was used, the values 1/n and K were 1.59 and 1.02 for Ni and 1.21 and 1.91 for Hg. Relatively similar results were obtained when the GAC was examined. This indicated the stronger adsorbability of mercury compared to nickel. When investigating the continuous system at different contact times the results indicated that increasing the contact time increased the metal : carbon removal efficiency. The overall results showed that the breakthrough points for either Ni or Hg reflected their adsorption isotherms as indicated by k values. Concludes that the addition of an activated carbon filter is recommended for the treatment of drinking water contaminated by heavy metals.

The notable dyeing performance and characteristics of polyfunctional heterocyclic azo dyestuff promoted us to design a programme specifically aiming to investigate efficient synthesis of several new isoxazole azo dyes. In the present work we investigate the dyeing performance of the newly synthesized isoxazole azo dyes.

The purpose of this paper is to present a finite element formulation of enhanced two‐node parabolic cable element for the static analysis of cable structures.

Unlike the assumed polynomial displacement interpolation functions, the present approach uses the analytical cable dynamic stiffness matrix to obtain the explicit expression of the static stiffness matrix of an inclined sagging cable by setting the frequency at zero. The Newton‐Raphson‐based iterative method is used to obtain the solution.

It is demonstrated that the present results agree well with those obtained from the nonlinear analytical theory of a parabolic cable and previous reported methods in the literature.

This paper proposes a two‐node parabolic cable element. For comparable accuracy with the truss element method, fewer numbers of such cable elements are needed.

This paper aims to investigate the strategy for low-cost yield optimization of miniaturized microstrip couplers using variable-fidelity electromagnetic (EM) simulations.

Usefulness of data-driven models constructed from structure frequency responses formulated in the form of suitably defined characteristic points for statistical analysis is investigated. Reformulation of the characteristics leads to a less nonlinear functional landscape and reduces the number of training samples required for accurate modeling. Further reduction of the cost associated with construction of the data-driven model, is achieved using variable-fidelity methods. Numerical case study is provided demonstrating feasibility of the feature-based modeling for low cost statistical analysis and yield optimization.

It is possible, through reformulation of the structure frequency responses in the form of suitably defined feature points, to reduce the number of training samples required for its data-driven modeling. The approximation model can be used as an accurate evaluation engine for a low-cost Monte Carlo analysis. Yield optimization can be realized through minimization of yield within the data-driven model bounds and subsequent model re-set around the optimized design.

The investigated technique exceeds capabilities of conventional Monte Carlo-based approaches for statistical analysis in terms of computational cost without compromising its accuracy with respect to the conventional EM-based Monte Carlo.

The proposed tolerance-aware design approach proved useful for rapid yield optimization of compact microstrip couplers represented using EM-simulation models, which is extremely challenging when using conventional approaches due to tremendous number of EM evaluations required for statistical analysis.

Samples of loomstate cotton fabric were first treated with aqueous potassium permanganate solution at different concentrations in the presence of a non‐ionic wetting agent. The samples were then washed and treated using solutions containing methacrylic acid, wetting agent and acid or basic dye along with citric acid of different concentrations at different temperatures for different times. The critical properties of the fabric such as graft yield (expressed as carboxyl content m.eq/100g cellulose), colour strength before and after soaping and percentage loss in colour strength due to soaping were found to depend on the concentrations of KMnO₄, citric acid and methacrylic acid as well as duration of the treatment. Based on the results obtained, treating formulations consisting of KMnO₄ (0.1g/l), citric acid (0.1g/l), methacrylic acid (50 per cent), dye (1 per cent) and wetting agent (2g/l) was considered appropriate for concurrent grafting and dyeing of the said fabrics provided that the treatment was carried out at 90°C for 60 minutes.

A water repellent fluorenated monomer was used in a mixture of monomers for treatment of pine wood samples, using both, impregnation and graft copolymerization methods. This resulted in obtaining a new wood‐based material, the properties of which are superior to those of the natural untreated one. The total polymer loading was generally low, but it was sufficient for improving the mechanical properties with an obvious decrease in the water uptake. Better results of bending strength can be obtained on treatment using the graft copolymerization technique, this can be attributed to the chemical bonding of the polymer with cellulose on grafting.

This article presents the galvanostatic anodic oxidation of two types of stainless steel alloys, ferritic (15.03% Cr) and austenitic (20.45% Cr, 8.37% Ni), in molten NaNO₃‐KNO₃ eutectic mixture at different temperatures ranging from 673‐873K. At a temperature of 673K the shape of polarization curves for the alloys is complex, while at higher temperatures it is simple. The passivity potential range was calculated as the difference between the passivation potential, E_p, and the breakdown potential, E_b. The value of E_b – E_p decreases with the increase of temperature. The amount of iron, chromium and nickel dissolved in the melt was determined after each experiment using atomic absorption spectroscopy. The composition and structure of the corrosion products formed on the surface of electrodes were examined by X‐ray diffraction analysis. Corrosion parameters derived from the polarization curves are calculated; these are: polarization resistance at low current densities, R_p, exchange current density, i_o, corrosion current density, i_corr, passivation current density, i_p. It was found that the increase of temperature increases i_o, i_corr, and i_p while R_p, decreases. From these results it was found that, under the given conditions, the austenitic stainless steel alloy is more corrosion resistant than the ferritic one. The activation energy of corrosion was estimated for the two alloys.