This study was conducted to investighate the adsorption of Cadmium from aqueous solutions by using the powder of excess sludge (biosolid) from municipal wastewater, at 24 to 26oC, a pH value of 2 to 6, over a contact time of 5-420 minutes, and at 50 to 300 rpm stirring rate in a batch reactor on the laboratory scale. The pretreatment of biosolids consisted of dewatering, grinding, and grainsizing with sieves (mesh dimensions between 50 and 120). According to the results, the best conditions for biosolids to adsorb Cadmium was pH=4, 120 minutes of contact time, and a stirring rate of 200 rpm. Cadmium adsorption kinetics followed the pseudo second order model. Maximum equilibrium adsorption was observed after two hours. The adsorption isotherm was in accordance with the Langmuir model. Maximum Cadmium adsorption capacity of biosolids (qmax) was estimated at 0.38 m-mol/g of dry biosolid (41.5 mg/g) and the Langmuir constant (kd) was found to be 0.1044 m-mol/lit (11.37 mg/lit).

Background: Recently, there has been a great concern about the consumption of dyes because of their toxicity, mutagenicity, carcinogenicity, and persistence in the aquatic environment. Therefore, the aim of this study was to determine the feasibility of using Lemna minor for Acid Blue 292 (AB292) dye removal from aqueous solution and to determine the optimal conditions.Methods: This experimental study was conducted in the batch systems to investigate the effects of parameters such as contact time, initial concentration of dye, pH and Lemna minor biomass dose. Isotherms and kinetic studies of dye adsorption were performed using equilibrium data.Results: According to the results, a maximum removal efficiency of 98.5% was obtained at pH of 3 and the contact time of 90 min; initial dye concentration 10 mg/L and adsorbent dose 3g/L. The adsorption data was best fitted to the Langmuir isotherm and pseudo-second order kinetic model.Conclusion: The results showed that Lemna minor could be used as a cost-effective adsorbent for removing AB292 dye from textile wastewater efficiently

Background and Objectives: The presence of heavy metals in aqueous sources is one of the most important problems that effects on health and environment. Adsorption by microorganisms using methods has many advantages. For this purpose, used microorganisms such as fungi, bacteria, and algae for removing heavy metals.Method: In this study the use of non-living fungal of Penicillium camemberti as biosorbent for removal of copper ions from aqueous solution was investigated in batch system and fixed bed column. In the batch system, for the biological absorption of copper, the parameters of temperature, pH, the dosage of bio sorbent and contact time were optimized. In the kinetic study of the bio sorption of copper metal by means of the non-living fungus, the Lagergren intraparticle diffusion models have been used.Findings: Considering the obtained results, it is determined that the biological absorption of copper using fungus follows from the second order equation because in the second order state, the amounts of qcal are close to the amounts of qexp and also R2>0.97.The results also demonstrate that an intra-particle diffusion mechanism play a significant role in the sorption process. In continues system, the biosorbent was turned into granul and the effects of hight and flow rate studied. The structure of Penicillium camemberti was characterized by IR spectrometer.Disscusion and Conclusion: The results also demonstrate that adsorption mechanism plays a significant role in the sorption process. The maximum bio sorption obtained from the batch process was 86.52% for biomass in pH=5.5.

The current study deals with evaluation of biosorption feasibility for removal of Cu (II) and Zn (II) by hybrid immobilized biosorbent of Pleurotus sajor-caju and Jasmine sambac. Batch adsorption experiments were carried out to assess the effect of pH, initial metal concentration, biomass dose, temperature and time. The biosorption efficiency of Cu (II) and Zn (II) ions for hybrid immobilized biosorbent increases with rising pH values. The hybrid immobilized biosorbent illustrated the highest biosorption capability at pH 5 for Cu (II), 6 for Zn (II), at 0.05 g/100 mL dose and 100 mg/L initial metal concentration of both ions. Uptake kinetics followed the pseudo-second-order model and equilibrium was described by Langmuir and Freundlich isotherms. Adsorption ratios of Cu (II) and Zn (II) were best fitted to Langmuir isotherm. The best temperature for ion uptake was found to be 30oC.

The adsorption of heavy metals onto treated Azolla filiculoides by H2O2/MgCl2, as a cosmopolitan free-floating waterfern, was investigated from aqueous solutions in the batch biosorption experiments. The maximum uptake capacities of the collected Azolla from rice field at the optimal conditions for Pb, Cd, Cu and Zn ions were approximately 228, 86, 62 and 48 mg/g (dry Azolla), respectively. On the other hand, the maximum uptake capacities of the collected Azolla from the Anzali International Wetland in the north part of Iran at the same conditions for these heavy metals were about 124, 58, 33 and 34 mg/g (dry Azolla), respectively. Such decrease of uptakes is due to the pollution of Anzali International Wetland, which reduces the capacity uptake of metals. The recovery of biosorbed heavy metals from the rice field Azolla was carried out by HCl and NaCl desorbents that the recovery of 64- 86% and 51-72% was occurred, respectively.

Batch sizing in different planning period is categorized as a classical problem in production planning, that so many exact & heuristic methods have been proposed to solve this problem, each of which considering various aspects of the original problem. The solution obtained from majority – e.g. MRP – is in this format that there may be some periods of idleness or each period should produce as needed in different adjacent periods. If there are more the one final independent product to be produced in a factory, this makes the production planning experience strong variations in batch sizes for different periods, which production managers are opposed to these proposed production plans. In this paper, some of the models are proposed to solve this shortcoming of the production plan to smooth the variation of batch sizes and consequently to meet the managers ideal. Finally all of the proposed models are used in a real case problem and the best model is introduced in that case.

Nine commercial almond cultivars ('Sahand', 'Yalda', 'Shukofeh', 'Azar', 'Ferragnes', 'Nonpareil', 'Monagga', 'A200' and 'A230') were used for determination of the flower initiation time, stages of morphological development of flower bud, flower buds density in spur, branch spur number of and pistil length. The experiment was conducted in 'Sahand' Horticultural Station during three years. For determination of flower initiation, buds were sampled weekly since 15 August. Results showed a positive correlation between initiation and flowering times. The first flower initiation period was observed in 'Monagha' (27 August) and the last flower organogenesis period was observed in 'Sahand' (26 November). Analysis of variance showed significant differences among cultivars in all studied characteristice (P≤5%). 'Sahand' produced the highest spur in each meter of branches with average of 46 spurs and 'Monagha' produced the highest pistil length with average of 1.85 cm. The important point in all the cultivars used was normal fruit setting despite short pistil production in some of them.