• Advances in environmental research
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• v.6 no.2
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• pp.127-137
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• 2017

Cotton is the major fiber crop in Pakistan that accounts for 2% of total national gross domestic product (GDP). After picking of cotton, the dry stalks are major organic waste that has no fate except burning to cook food in villages. Present research focuses use of cotton stalks as feedstock for biochar production, its characterization and effects on soil characteristics. Dry cotton stalks collected from agricultural field of Bahauddin Zakariya University, Multan, Pakistan were combusted under anaerobic conditions at $450^{\circ}C$. The physicochemical analysis of biochar and cotton stalks show higher values of % total carbon, phosphorus and potassium concentrations in biochar as compared to cotton stalks. The concentration of nitrogen was decreased in biochar. Similarly biochar had greater values of fixed carbon that suggest its role for carbon sequestration and as a soil amendment. The fourier transformation infrared spectroscopic spectra (FTIR) of cotton stalks and biochar exposed more acidic groups in biochar as compared to cotton stalks. The newly developed functional groups in biochar have vital role in increasing surface properties, cation exchange capacity, and water holding capacity, and are responsible for heavy metal remediation in contaminated soil. In a further test, results show increase in the water holding capacity and nutrient retention by a sandy soil amended with biochar. It is concluded that cotton stalks can be effectively used to prepare biochar.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.5 s.108
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• pp.29-35
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• 2004

Fiber dimensions, their derived values and chemical properties of cotton stalks (Gosypium hirsutum L), jute stick (Corchorus capsularis) and dhancha (Sesbania aculeate) have been examined to assess their suitability for paper production. Cotton stalks have a good derived values especially slender ratio, which is comparable to hardwood. The flexibility coefficient of these three non wood plants is better than hardwood. Anatomical analysis shows higher percentage of fibers and vessels than in general non wood plants. Lignin, $\alpha$-cellulose and pentosan contents in these three nonwood plants are within the range of hardwood. Neutral sugar analysis of cotton stalks, jute stick and dhancha shows that the glucose in the major sugar followed by xylose and mannose. The arabinose and galactose are present in minor amount. Alkaline nitrobenzene oxidation of cotton stalks, jute stick and dhancha wood meal exhibits that these nonwood plant lignins mainly consist of syringyl (S) and guaiacyl (V) units. The S/V ratios are 1.6, 1.2 and 2.1 for cotton stalks, jute stick and dhancha, respectively.

• Carbon letters
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• v.14 no.1
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• pp.14-21
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• 2013

Physically and chemically activated carbons (ACs) exhibited high adsorption capacities for organic and inorganic pollutants compared with other adsorbents due to their expanded surface areas and wide pore volume distribution. In this work, seven steam-ACs with different burn-off have been prepared from cotton stalks. The textural properties of these sorbents were determined using nitrogen adsorption at $-196^{\circ}C$. The chemistry of the surface of the present sorbents was characterized by determining the surface functional C-O groups using Fourier transform infrared spectroscopy, surface pH, $pH_{pzc}$, and Boehm's acid-base neutralization method. The textural properties and the morphology of the sorbent surface depend on the percentage of burn-off. The surface acidity and surface basicity are related to the burn-off percentage. A theoretical model was developed to find a mathematical expression that relates the % burn-off to ash content, surface area, and mean pore radius. Also, the chemistry of the carbon surface is related to the % burn-off. A mathematical expression was proposed where % burn-off was taken as an independent factor and the other variable as a dependent factor. This expression allows the choice of the value of % burn-off with required steam-AC properties.

• Carbon letters
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• v.11 no.3
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• pp.224-234
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• 2010

Four activated carbons were produced by two-stage process as followings; semi-carbonization of indigenous biomass waste, i.e. cotton stalks, followed by chemical activation with KOH under various activation temperatures and chemical ratios of KOH to semi-carbonized cotton stalks (CCS). The surface area, total pore volume and average pore diameter were evaluated by $N_2$-adsorption at 77 K. The surface morphology and oxygen functional groups were determined by SEM and FTIR, respectively. Batch equilibrium and kinetic studies were carried out by using a basic dye, methylene blue as a probe molecule to evaluate the adsorption capacity and mechanism over the produced carbons. The obtained activated carbon (CCS-1K800) exhibited highly microporous structure with high surface area of 950 $m^2/g$, total pore volume of 0.423 $cm^3/g$ and average pore diameter of 17.8 ${\AA}$. The isotherm data fitted well to the Langmuir isotherm with monolayer adsorption capacity of 222 mg/g for CCS-1K800. The kinetic data obtained at different concentrations were analyzed using a pseudo-first-order, pseudo-second-order and intraparticle diffusion equations. The pseudo-second-order model fitted better for kinetic removal of MB dye. The results indicate that such laboratory carbons could be employed as low cost alternative to commercial carbons in wastewater treatment.

• Carbon letters
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• v.12 no.1
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• pp.1-7
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• 2011

In the present study, the removal of Pb (II) ions on oxidized activated carbons (ACs) was investigated. ACs were derived from activation of indigenous cotton stalks waste with potassium hydroxide (KOH) in two-stage process. The KOH-ACs were subjected to liquid-phase oxidation with hot $HNO_3$ and one untreated sample was included for comparison. The obtained carbons were characterized by Fourier transform infrared (FTIR), slurry pH and $N_2$-adsorption at 77 K, respectively. Adsorption capacity of Pb (II) ions on the resultant carbons was determined by batch equilibrium experiments. The experimental results indicated that the oxidation with nitric acid was associated with a significant increase in mass of yield as well as a remarkable reduction in internal porosity as compared to the untreated carbon. The AC-800N revealed higher adsorption capacity than that of AC-800, although the former sample exhibited low surface area and micropore volume. It was observed that the adsorption capacity enhancement attributed to pore widening, the generation of oxygen functional groups and potassium containing compounds leading to cation-exchange on the carbon surface. These results show that the oxidized carbons represented prospective adsorbents for enhancing the removal of heavy metals from wastewater.

• Journal of Sericultural and Entomological Science
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• v.47 no.2
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• pp.78-87
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• 2005

In this thesis, we took some stalks, flowers, and leaves of the Hypericum ascyron L. which are able to propagate as mass in our wild to extract the dyeing solution, and cotton and silk were dyed using them in many different conditions. Silk was dyed darker than cotton with increasing the pH density. Silk was dyed darkest among Hypericum ascyron if pH was neutral. We found there was not a big difference between silk and cotton in the given condition considering 'Y' values vs. dyeing temperature. However cotton was dyed darker in hypericum ascyron. There was a rapid decreasing of 'Y' values after one to two hours and almost all of dyeing was completed at these times. We found there was a dyeing acceleration at the higher dyeing density and the lower 'Y' value. If the density was low, dyeing attachment was reduced by dyeing ability via the density of liquid in this plants. Silk was affected higher by mordant dyes in this plants. Fe and Cu had no effect on Hypericum ascyron.

• Horticultural Science & Technology
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• v.16 no.1
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• pp.42-44
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• 1998

The effect of medium composition on PLB formation and multiplication and shoot regeneration was studied to establish the micropropagation system of the tropical orchid Phalaenopsis. The highest frequence of PLB formation resulted from the VW medium with 1.2 times ion concentration, 1% sucrose, 1.5g/L PVP or 2.5g/L active charcoal, apple and potato extract and 4g/L gellan gum. The highest ratio of PLB multiplication was obtained from the VW medium with 2% sucrose, apple and potato extract and cotton plate. The shoot regeneration was the most effective with the hyponex medium with 3% apple, 3% potato and 4% banana extract.

• Journal of Sericultural and Entomological Science
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• v.48 no.2
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• pp.46-55
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• 2006

In this thesis, we took some stalks, flowers, and leaves of the Serratuls coronate var. insularis which are able to propagate as mass n our wild to extract the dyeing solution, and cotton and silk were dyed using them in many different conditions. Silk was dyed darker than cotton. We found there was not a big difference between silk and cotton in the given condition considering 'Y' values vs. dyeing temperature. There was a rapid decreasing of 'Y' values after one to two hours and almost all of dyeing was completed at these times. We found there was a dyeing acceleration at the higher dyeing density and the lower 'Y' value. If the density was low, dyeing attachment was reduced by dyeing ability via the density of liquid in both plants. Silk was affected higher by mordant dyes in both plants. Fe and Cu had an effect by mordant dyes slightly an Serratuls coronate var. insularis.