objectives: scaling and root planing (srp) is one of the most commonly used procedures during periodontal treatment. the aim of this study was to evaluate the root surface roughness after srp with erbium: yttrium aluminum garnet (er:yag) laser compared to ultrasonic and hand instruments.   materials and methods: in this experimental study, 56 extracted sound single-rooted teeth with moderate le...

background and objectives: analytical methods for volatile organic compounds (vocs) in different samples need extraction of compounds, by applying hazardous solvents. solid phase micro-extraction (spme) is a solvent-free equilibrium extraction method, in which proper calibration can allow quantitative determinations of vocs at a very good sensitivity without the use of any organic solvent. vocs...

background and objectives: bacillus species are attractive industrial organisms due to their rapid growth rates leading to a short fermentation cycle and for their capacity to secrete important enzymes and proteins such as xylanase into the extracellular medium. considering the industrial importance of xylanase, in this current study, bacillus spp. were isolated from different soils and were sc...

background: determination of organic pollutants usually requires extraction of the pollutants from samples, using hazard­ous solvent. solid phase micro-extraction (spme) is a solvent-free equilibrium extraction method, in which, proper calibra­tion can allow quantitative measurements of organic pollutants at a very good sensitivity without the use of any organic sol­vent. because individual voc...

acetonitrile used as a solvent in manufactures and affects to central nervous system from inhalation exposure. the aim of this study was to develop a micro-solid phase extraction method for  the determination of acetonitrile in the air matrix. the sampling was performed with a small diameter fused silica fiber coated with a thin film of stationary phase and was subsequently desorbed and analyze...

Organic fraction of solid waste, which upon degradation produces foul smell and generates pathogens, if not properly managed. Composting is not a method of waste disposal but it is a method of waste recycling and used for agricultural purposes. An integrated approach of composting methodology was tested for municipal solid waste management. Solid waste first was composted and after 22 days, was...

Introduction: Dental wastes are a main part of urban solid wastes in each society and have pathogenic agents and toxic chemicals, which put health of patients, personnel and other referees to dental clinics in danger. The present study  was done to recognize the quality and quantity of the different generated wastes at various parts of the Faculty of Dentistry-Babol University of Medical S...

Background and Purpose: Improper wastewater and solid waste management in rural areas could be a risk to human health and environment pollution. One percent of Iran’s rural area is connected to the wastewater collection network. Solid waste management in rural areas of Iran is mainly consisted uncontrolled dumping and open burning. The aim of this study is prioritization of wa...

Background & Aims of the Study:  Collection and transportation of municipal solid waste (MSW) for various reasons, especially economic and social are considered as one of the most important elements of the solid waste management system. More than sixty percent of the costs in solid waste management systems in different countries are due to the collection and transportation...

The dynamics of sharp interfaces separating two nonhydrostatically stressed solids is analyzed using the idea that the rate of mass transport across the interface is proportional to the thermodynamic potential difference across the interface. The solids are allowed to exchange mass by transforming one solid into the other, thermodynamic relations for the transformation of a mass element are der...