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The purpose of this paper is to study some chemical reactions of viscose grade pulp (alpha cellulose around 96 per cent) prepared by preoxyacetic acid pulping of bagasse for the preparation of some cellulose derivatives.

Viscose grade pulp was prepared by using ecological chemicals. The viscose grade pulp was subjected to some chemical reactions (e.g. carboxymethylation, cyanoethylation and phosphorylation reactions). The pulping and bleaching which are two important stages involved in the complex process of converting fibrous raw material (bagasse) into viscose grade pulp are also investigated in this paper.

The viscose pulp prepared by peroxyacid pulping of bagasse was subjected to a number of chemical reactions such as: hydrogel and fibrous carboxymethyl cellulose; cyanoethyl cellulose, in which this cyanoethylcellulose (of gel properties) was prepared, the hydrophobic character of the cyanoethylcellulose was changed into hydrophilic character via hydrolysis by NaOH (2.5 per cent w/v) which converts some of the CN groups into COOH; and cellulose phosphate. Infrared spectroscopy of these derivatives was studied. New bands were observed at 3,120, 2,251, 1,200 and 980 cm⁻¹ which characterised to groups, respectively.

The paper documents the preparation of some cellulose derivatives which have high water absorption and can be used as hydrogel materials such as carboxymethyl and hydrolysed cyanoethyl cellulose and ion exchange properties.

Bagasse and rice straw lignins undergo different treatments, e.g. acid hydrolysis, oxidation with hydrogen peroxide and thermal treatment, before being used as a partial replacement for phenol in phenol formaldehyde resin. These treatments improved the resin formation properties of the lignin. The effect of these treatments on the improvement of the properties of the resin produced has the following sequence: lignin treated with HCl (1‐3N) > lignin treated with H₂O₂ (1‐3 per cent) > thermally treated lignin (120‐140°C). The improvement of the properties of the resin produced from bagasse lignin is greater than that produced from rice straw lignin. The treatment of rice straw lignin with acid increases its ability to form a resin. Treatment of rice straw lignin with acid leads to its increased concentration in the phenol lignin formaldehyde resin with good properties. In general, the resin produced from treated lignin has better properties than resin produced from untreated lignin.

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.

Presents findings from a study of the effects of treating unbleached bagasse paper sheets with different resin solutions. Unbleached kraft bagasse paper sheets were treated with different resin solutions such as nitrocellulose, melamine formaldehyde, silicone, short and medium alkyd resin and the physico‐mechanical properties of the modified paper sheets were tested. The strength properties of treated paper sheets were highly improved especially in the case of treatment with melamine formaldehyde and silicone resin solutions. The effect of dipping time of paper sheets in different concentrations of resin solution on the strength properties was also investigated. Physico‐mechanical properties of thermally treated modified paper sheets with resins were also clarified. Concludes that promising results in the improvement of insulation of treated paper sheets with resin are obtained by studying the dielectric‐electric properties.

The purpose of this paper is to study the effect of treatment using hydrophilic and hydrophobic polymers on mechanical properties and/or water absorption of paper sheets.

Paper sheets produced from paper grade wood pulp were dipped in polyacrylamide (PAA), polymethylmethacrylate (PMM) and polyvinyl alcohol (PVA) polymer solutions, respectively. The effects of using different polymer solutions (PAA, PMM and PVA), as well as the effects of dipping time (1, 5 and 10 min) and concentration of polymer (0.5, 1, 2 and 3 per cent), on the mechanical properties as well as water absorption of paper sheets were investigated.

It was found that the treatment of paper sheets with different polymer solutions improved mechanical properties as well as water absorption of paper sheets when the polymer concentration was below 1 per cent and the dipping time did not exceed 5 min.

Paper sheets resulting from treatment using hydrophilic polymers can be used as printing papers as the printability improves because water absorption improves, while paper sheets resulting from using hydrophobic polymers can be used for packaging because water adsorption is less and breaking length improved.

Improving some mechanical properties and/or water absorption of paper sheets. The improvement of dipped sheets increased by increasing dipping time till 5 min and by increasing polymer concentration till 1 per cent. Utilisation of PAA led to best results especially when it was hydrolysed.

The purpose of this paper is to prepare and optimize the preparation conditions of some new hydrogels and in addition, evaluate their water absorbance at different mediums and their ability to remove ions from aqueous solutions.

Cellulose was extracted from depithed bagasse at two different pulping conditions; 3 and 6 hours cooking times, pulp (I) and (II), respectively. These pulps, in addition to cotton linter for comparison, were grafted with acrylamide followed by cross‐linking with glutaraldehyde. The networks were partially hydrolyzed and the structures of products (before and after hydrolysis) were studied using FTIR, SEM, TGA and X‐ray. The optimum preparation conditions were identified, before and after hydrolysis, to achieve maximum absorbance and the ability of prepared hydrogels to remove ions from solutions was investigated.

Maximum level of absorption was recorded using hydrogels prepared with monomer concentration =0.8 mol/l, cross‐linker concentration =0.01 mol/l, reaction time =2 hours and temperature =65°C. Hydrogels prepared using pulp (I) showed the best absorbance behavior and a tendency to remove ions from water.

The ability of the prepared gels to remove ions from water could be further investigated to evaluate the ability of their use in a multi‐filtration system for water treatment.

This piece of work has suggested a simple way to convert an agricultural waste to hydrogel able to remove metal ions from water.

Consuming this type of waste reduces the risks resulting from its burning in some countries, such as Egypt, that produce large amounts of it.

In this paper, low cost hydrogels, with expected value in water treatment, were prepared using agricultural wastes. They have shown better reactivity than gels prepared using pure cellulosic materials (cotton linter).

Lignin precipitated from different black liquors wasted from the cooking of rice straw, bagasse and cotton stalks, to produce pulp and paper, can replace phenol by up to 40 per cent in phenol formaldehyde resin. The properties of the resin produced from bagasse lignin formaldehyde are nearly the same as when the resin IS produced from phenol formaldehyde. Replacement of phenol by lignin in phenol formaldehyde resin has an economical effect and reduces the pollution caused by draining black liquor into rivers and streams. The properties of the resin produced from rice straw lignin are lower than resin from bagasse and cotton stalk lignin. The effect of increasing the content of lignin in the resin on the resin properties was studied. The effect of polymerization time and temperature on the resin properties is also clarified. The molecular structure of the lignins used plays an important role on the properties of the phenol lignin formaldehyde produced.

This paper aims to clarify the mechanism by which heuristics influences the investment decisions of individual investors, actively trading on the Pakistan Stock Exchange (PSX), and the perceived efficiency of the market. Most studies focus on well-developed financial markets and very little is known about investors’ behaviour in less developed financial markets or emerging markets. The present study contributes to filling this gap in the literature.

Investors’ heuristic biases have been measured using a questionnaire, containing numerous items, including indicators of speculators, investment decisions and perceived market efficiency variables. The sample consists of 143 investors trading on the PSX. A convenient, purposively sampling technique was used for data collection. To examine the relationship between heuristic biases, investment decisions and perceived market efficiency, hypotheses were tested by using correlation and regression analysis.

The paper provides empirical insights into the relationship of heuristic biases, investment decisions and perceived market efficiency. The results suggest that heuristic biases (overconfidence, representativeness, availability and anchoring) have a markedly negative impact on investment decisions made by individual investors actively trading on the PSX and on perceived market efficiency.

The primary limitation of the empirical review is the tiny size of the sample. A larger sample would have given more trustworthy results and could have empowered a more extensive scope of investigation.

The paper encourages investors to avoid relying on heuristics or their feelings when making investments. It provides awareness and understanding of heuristic biases in investment management, which could be very useful for decision makers and professionals in financial institutions, such as portfolio managers and traders in commercial banks, investment banks and mutual funds. This paper helps investors to select better investment tools and avoid repeating expensive errors, which occur due to heuristic biases. They can improve their performance by recognizing their biases and errors of judgment, to which we are all prone, resulting in a more efficient market. So, it is necessary to focus on a specific investment strategy to control “mental mistakes” by investors, due to heuristic biases.

The current study is the first of its kind, focusing on the link between heuristics, individual investment decisions and perceived market efficiency within the specific context of Pakistan.

Milton Nascimento is one of the most prolific Brazilian singers and songwriters of all time, an artist who has formed friendships and made songs with a host of Brazilian artists, with international stars from Latin America, and with artists abroad. Milton’s repertoire has made its way into the fabric of musical compilations of Brazilian music for international listeners. Perhaps unbeknownst to these international listeners, Milton, as an Afro-Brazilian artist, reflects a complex and paradoxical relationship to “race” in his music – at times openly touching upon racial themes, even during an area when the government forbade open discussion of racial tension in Brazil – but at times signifying race more subtly, either through subtle references to diversity in Brazil or through the very elements of his music.

Reports on tests in which barium metaborate pigment and its modified form are prepared, identified by chemical and X‐ray diffraction methods, and specified according to standard methods. Evaluates the modified barium metaborate as a new filler for paper making by carrying out two series of experiments. Details the results which showed that the efficiency of the filler retention when using modified barium metaborate was higher than that of the other two conventional fillers. Reveals that at relatively low filler addition (2–5 percentage weight), higher improvement in the strength properties can be obtained when using the modified pigment instead of titanium dioxide and kaolin, but observes the reverse (i.e. a detrimental effect) at relatively high filler addition (8–10 percentage weight). Discovers that the optical properties of the modified pigment‐loaded sheets lie between those of titanium dioxide and kaolin. Shows that blending barium metaborate with kaolin or titanium dioxide has a significant effect on strength properties rather than optical properties. Concludes that modified barium metaborate pigment can be successfully used in paper filling applications and that modified barium metaborate pigment‐kaolin blend (80/20 per cent) can be used instead of titanium dioxide as a paper filler.