In comparison with existing designs, suggested backpack design can reduce forces on upper limb during handling the backpack

Background: Water treatment sometimes needs a coagulation and flocculation process to remove suspended and colloidal materials. Inorganic coagulants used create concerns about pollution of the environment and harmful effects on the human's health. The studies carried out previously indicated the capability of an active coagulant agent extracted from Descurainia Sophia seed to remove turbidity of water

Methods: : The purpose of this study was to investigate the effect of NaCl [0.05-1 gL-1], NaOH [0.01-0.1 gL-1], extraction duration [1-25 min] and the ultrasound frequency [0-45-75 kHz], used in the extraction of Descurainia Sophia seed, on the generation of color in purified water and to provide a model to predict the effects of the studied variables on color generation. Extraction was performed using water as solvent, supplemented with NaCl and NaOH and irradiated by ultrasound. Design of experiments and analysis of results were conducted by the D-optimal method based on the response surface methodology [RSM]

Results: The results demonstrated that only the effect of concentration of NaOH is significant in color generation [with p and It;0.05]

Conclusion: The effect of NaOH on color generation in purified water is predictable by the use of a statistically valid linear model at a confidence level of 95%

Investigation of enzyme immobilization effects on its characteristics

Background: Enzymes are well known as sensitive catalysts in the laboratory and industrial scale. To improve their properties and for using their significant potential in various reactions as a useful catalyst the stability of enzymes can often require improvement. Enzymes Immobilization on solid supports such as epoxy- functionalized ferric silica nanocomposite can be effective way to improve their characteristics

Methods: In this study silica coated magnetite nanoparticles were Functionalized with GPTSM as a linker, then immobilization reaction performed by using various amounts of lipase B from Candida Antarctica [CALB], for the next step immobilization effects on thermal stability and optimum pH were investigated in comparison with free CALB

Results: Results illustrated enzyme was successfully immobilized on nano particles and immobilized derivative retains 100% of its activity by 55 degree C while free CALB loss its activity at the same condition

Conclusion: Immobilization of CALB on Fe3O4@SiO2 particles resulted in significant improvements in its characteristics such as thermal stability and methanol tolerance compared to the free CALB

effect of paved roads on organic carbon content of soil in Taham Dam Basin

Background: Contamination of water and soil through non-point sources such as road runoff causes environmental concern. The aim of this study is to determine the effect of Zanjan - Chavarzagh road on the total organic carbon [TOC] content of sediments in tributaries and the river that lead to Taham Lake

Methods: In tributaries and the river 69 soil and sediment samples were taken and the Total organic carbon [TOC] was measured according to Walkely-Black method. Also, Taham Dam Basin area and its hydrologic properties were calculated by Global Information System [GIS] software

Results: Results showed that, TOC concentration has a significant negative relationship with the distance from the lake. TOC in soil samples taken from hillside of the road had significantly lower mean and median concentration [ median= 3262 , mean = 4083 +/- 3461 mg/kg] than the valley side [ median = 5324 , mean = 6178 +/- 3980 mg/kg]. The check dams across the tributaries and the river have not been effective in the reduction of TOC in sediments

Conclusion: Roads in the Taham Dam Basin, increases TOC content of soil and sediments in Taham dam basin. TOC moves toward Taham dam lake

Comparison of water turbidity removal efficiencies of descurainia sophia seed extract and ferric chloride

Background: Turbidity removal using inorganic coagulants such as iron and aluminum salts in water treatment processes causes environmental and human health concern. Historically, the use of natural coagulant to purify turbid water has been practiced for a long time. Recent research indicates that Descurainia Sophia seed can be effectively used as a natural coagulant to remove water turbidity

Method: In this work, turbidity removal efficiency of Descurainia Sophia seed extract was compared with Ferric chloride. Experiments were performed in laboratory scale. The coagulation experiments were done with kaolin as a model soil to produce turbidity in distilled water. The turbidity removal efficiency of Descurainia Sophia seed extract and Ferric chloride were conducted with jar test apparatus. In all experiments, initial turbidity was kept constant 100[NTU]. Optimum combination of independent variables was used to compare two different types of coagulants

Result: The obtained results showed that Ferric chloride could remove 89.75% of the initial turbidity, while in case of Descurainia Sophia this value was 43.13%. The total organic carbon [TOC] analysis of the treated water using seed extract showed an increased concentration of TOC equal to 0.99 mg/L

Conclusions:This research has shown that Descurainia Sophia seed extract has an acceptable potential in the coagulation/flocculation process to treat turbid water