Aim: The aim of this study was to compare the effects of Ethylen glycol tetra acetic acid (EGTA) and EDTA for their smear layer removal capability using scanning electron microscopy technique.Material and Methods: A group of 28 single rooted teeth were instrumented to size 60 master file. Four teeth were also kept as control while the remaining teeth were divided into two groups. Group A: in which 12teeth were irrigated with 10 ml of 17% EGTA for 2 minutes? Group B: consisted of 12teeth irrigated with 10 ml of 17% EDTA for 2 minutes. Both groups were then irrigated with 10 ml of 5% Naocl. the control group were just irrigated with 10 ml of 5 % Naocl. All teeth in then the control group were only irrigated with 10 ml of 5% Nacl. Specimeus were then sectioned longitudinally. A scanning electrone microscope was wsed to in vetig ate the intenal surfaces of the canal.Results: EGTA chelated dentin surface more conservatively than EDTA without causing erosion.Conclusion: It seems that EGTA can be used safely to remove smear layer from the canal surfaces.

Background and Objective: Formaldehyde (CH2O) is one of the toxic volatile organic compounds which must be removed from polluted air. One of the techniques available to remove is by use of adsorbents. The aim of this study was to evaluate the characteristics and adsorption capacity of modified black bone char (BBC) on CH2O vapor.Subjects and Methods: In this experimental research two types of BBC adsorbents (nomal and modified) were produced.Specific surface area and pore volume of the adsorbent materials were determined using the Brunauer-Emmett-Teller (BET) surface area. The adsorbents structures were analyzed using scanning electron microscopy. The composition of BBC and modified BBC were analyzed by energy dispersive X-ray (EDX) measurement. To investigate breakthrough characteristics and adsorption capacity according to inlet concentration of CH2O on bone chars, adsorption experiments were carried out at 25±1oC under the same conditions.Results: The specific surface area and pore volume for modified BBC (118.58m2/g and 0.374 cm 3/g) were higher than for BBC (105.24m2/g and 0.367 cm3/g). The EDX analysis showed that amount of calcium of the modified BBC was less than that of BBC. The results also showed that mean value of equilibrium time of modified BBC was longer than that of BBC (P<0.05).Moreover, the mean value of adsorption capacity of modified BBC was higher than that of BBC (P<0.05).Conclusion: The modification of black bone char promotes porosity and adsorption capacity and can increase the removal efficiency of CH2O in air.

It is of great interest and remains a challenge to simultaneously improve the compatibility and flame-retardant performance of lignin/epoxy resin (EP) composites. In this work, a polysiloxane-enwrapped phosphorus-containing lignin-based flame retardant (PHMS-lig-P) was prepared through reactions of lignin, PHMS and TCP to address this issue, with results showing significantly improved flame-retardant performance and comprehensive performance. The influence of PHMS-lig-P on the flame retardancy of EP was investigated by vertical burning test (UL-94V), limiting oxygen index (LOI), smoke density test and cone calorimeter (CC) test. The PHMS-lig-P/EP achieved a V-1 rating, and its LOI value increased to 25. 3%. The maximum smoke density (Ds, max) decreased by 83. 2%. Furthermore, pHRR, avHRR, and MLR of PHMS-lig-P/EP decreased by 37. 5%, 22. 6%, and 25. 1%, respectively. In addition, the evolved gases and char residues were studied using thermogravimetric analysis coupled with Fourier transform infrared spectrometry (TG-FTIR) and scanning electron microscopy (SEM). The results certified the flame-retardant mechanism of PHMS-lig-P was attributed to the synergistic effect of lignin, phosphonate, and polysiloxane, producing a compact and cohesive char layer that acted as a physical barrier, limiting the transfer of heat and oxygen and preventing the spread of pyrolysis volatiles and flammable gases. Moreover, the flame-retarded epoxy resin possessed good dispersion uniformity in mechanical properties and insulation performance, showing good applicability.

Environment and its conservation is one of the present issues in risky modern life. Although, the present world has been improving during last years, it hasn’t been able to solve environmental problems and it has caused its deterioration. Littering in jungle, seashore, public places and passages is one of the significant environmental issues in society of Iran. The Purpose of the present study is investigation of the reasons of littering formation by the approach of Causal Layered Analyses (CLA) and planning scenario. The present study analyzed the layers forming the present social issue and searched the origin of it. In order to accomplish this study, 15 experts in environment and society were interviewed by Qualitative and exploring method and applying deep interview technique. Then, after exploiting the contents and content analysis of interviews, their opinions presented in 4 forms as litany, systematic, discourse analysis and metaphor. By applying the present discourses, the gap between state-people and people-people were recognized as important variables and were applied in presenting scenario. Finally 4 scenarios presented in a diagram which can help strategists and officials of the society.

Medicinal plants contain active ingredients in one or some of their organs. Squalene is one of the active ingredients that prevent heart attacks and cardiovascular diseases and protect the body from some cancers. The aim of the present study was to investigate the presence of squalene in a number of medicinal plants. In this experiment, the plant oils were extracted and measured using Bligh & Dyer with minor changes. TLC (thin layer chromatography) was used to identify squalene. Comparison of TLC of standard squalene with TLC of the investigated medicinal plant samples showed that Caryophillium aromaticus, Descurainia sophia, Portulaca Oleracea, Papaver somniferum and Nigella Sativa contained squalene. Although the percentage of Papaver somniferum and Nigella Sativa seed oil was higher than other medicinal plants, the squalane spot of clove plant had a higher intensity of color and this indicates a higher concentration of squalene in this plant.

This study was aimed at the development of the ZnO/bone-char (ZnO/BC) hybrid composite and it was characterized by its suitability for the treatment of dye-containing wastewater. The Zn/BC composites were prepared using four different methods such as sol-gel, precipitation, hydrothermal and wet-impregnation methods. Various analyzing techniques such as X-Ray Diffraction (XRD), Fourier Transform Infra-Red (FT-IR), Brunauer-Emmett-Teller (BET) surface area, and Scanning Electron Microscopy (SEM) were performed to characterize the prepared photocatalysts. The photocatalytic activity of the ZnO/BC composite prepared from the sol-gel method was evaluated by the decolorization of brilliant green dye in an aqueous solution. The results of SEM analysis confirm the agglomeration of nano-ZnO particles and particles are evenly distributed on the surface of the bone char. Moreover, the influence of different experimental parameters like solution pH, H2O2 concentration, and photocatalyst dosage was studied to optimize the process efficiency. This study also shows that chicken bone waste can be used as a photocatalyst carrier for the synthesis of photocatalytic composites. It not only provides a better way to treat dye-containing wastewater but also offers an ideal solution to using chicken bone waste. From the kinetic analysis, it has been observed that the photocatalytic decolorization of BG dye with ZnO/BC photocatalyst follows pseudo-first-order kinetics.

The endotoxin is one of pollutants with lipopolysaccharide structure which release from gram negative bacteria and cyanobacters. The aim of this study was removal of endotoxin from water using catalytic ozonation by bone char. The endotoxin for experiments have extracted from Escherichia coli bacterium cell wall by Stefan and Jan method. Chromogenic limulus ambusite lysate method in 405-410 nm wave length was used for analysing of endotoxin. The ozone have analysed by potassium iodine method. Results: Results of the research shown endotoxin removal rates using heterogenous catalytic ozonation were 6.0 Eu/ml.min and 0.5 Eu/ml.min for grey bone char and white bone char, respectively. The efficency of the process was found eighty percent. Primary concentration of basic compounds had no effect on endotoxin removal rate. Therefore, endotoxin removal kinetic of reaction is a zero order reaction. This study revealed that ozonation process using bone char is more efficient than other proposed methods such as ozonation or chlorination and can be used successfully for endotoxin removal from water as a efficient method.