نشریه انسان و محیط زیست
سال هفتم شماره 2 (پیاپی 9، تابستان 1388)

Methyl Tertiary-Butyl Ether (MTBE) is one of the gas additives that can be more effective in increasing the octan rating of fuel. EPA (Environmental Protection Agency) has labeled MTBE in carcinogen compounds.This compound can leak into the soil from underground fuel tanks and its chemical and physical properties affords rapid influence.Sorption ability of soil, is so effective in influence of MTBE into the soil and “distribution Coefficient (Kd)” can show this ability. Kd is one of the important effectives that recently lionizes in Environmental Geotechnics and its range is so wide in as much as it can be “0” or “1000” and more; This wide range is important in using numerical models for underground water and contaminant trasformation modeling.In this study, the real value of sorption has been determined by several sorption tests on MTBE and the soil of Ray city and according this value, various isotherm models were studied to find the most accurate model for MTBE and this soil.In this study, all of the tests have done according to ASTM standards.
Finally, it’s concluded that all of studied models are appropriate for calculating Kd but in similar cases,  we can offer foloing models sequently: Dubinin-Radushkevich Model; Langmuir Model; Freundlich Model; Linear Model.

In most rice paddies in Mazandaran Province, Diazinon is applied to control Chilo suppressalis.Due to the extensive application of insecticides in the rice paddies of the Caspian coasts of Iran, thisinvestigation was carried out on the rice fields and rice granules in order to obtain the necessary dataand information on the concentration of insecticide residues. This study was done in a center in AmolTownship in 1386 by using thin-layer chromatography in order to investigate Diazinon on 125 samples.Sampling period was one day after spraying until observing Diazinon. Results indicate that the insecticide is used frequently to combat stem boring caterpillar of rice and citrus tree’s pest. The residuals of this toxic chemical were observed in the majority of stations from the day after the spraying until one to two months later. The greatest level of Diazinon, was in Station #1 in amount of 1.14 ppm. This study revealed that the physical and chemical properties of the studied insecticides such as fumigation quality as well as the ecological conditions and soil type influence the reduction and eventual removal of the insecticides during the cultivation and harvest periods.

In recent years, increasing growth of energy consumption indicates economic growth, industrial improvement and thus, economic expansion. In the other side, perhaps due to low cost of energy in Iran, industry authorities and consumers do not properly use of it which result in special rules. However, energy audit is an efficient tool which helps responsiblesto plan for energy. Therefore, important issue which  is discussed here related to software analysis statein auditing energy in buildings. Finnally, the paper leads to introduce some sofware packages which can be used for this proccess and their advantages and shortcomings.

 The Hydro peaks induced by frequent starting and stopping of hydropower plant turbines are considered to cause the erosion of riverbed, more sediment generated, reduced permeability of the riverbank and also their regularity and hightemporal frequency produce grave impacts on river environment. Low fluctuation of natural river flow leads to low harm and provide best situation for environment. Thus, rehabilitation and hydro peak reduction of hydropower plant are the effectiveaffairs for environment support. This can be realized by a combination of different hard technical and soft operational measures such as retention reservoirs or slower up and down ramping of turbines. The characteristics of several turbine types are analyzed. The carrying capacity of a cross flow turbine is regarded to have the widest range. Inaddition, the width of the range may be expanded with special auxiliary equipment. This type of turbine is equivalent to two or even three turbines of varying capacities, and it can handle the discharges from any season. Rehabilitation and change in hydropower plant turbine for hydro peak reduction are discussed in this study and results show the efficiency of these changes.

One way to develop the implementation ofenvironmental regulations at international levelis to expand international liability scope of statesthat breach regulations. In this regard, seriousefforts have been done in past years, as considerableevaluations have been occurred. Nowadays, evaluationsin case of international liability resultingfrom environmental damages such as developmentin scope of liability (changes from error- basedliability to principle of danger- based liability),expanding environmental liability to privatesector, acceptance of criminal liability for whodamage to environment, and so on. Generally, allof them express change in liability regime in thecase of environment at international level. AndBasel Convention is a good sample of these evaluations.

Mineral water and drinking water are one of thevital and immediate needs for human beings.Depending age and weather, everybody needsabout one to two liters. The origin of 80% ofhuman diseases is unavailability of healthywater,75%percentofpeople in developingcountriesare deprived of facilities for water.Actually, healthywater scarce and expensive. Pollutions descend thequality of water by changing it physically,chemically and biologically .Some of the pollutionsare decadence and can be decreased easily, likehuman, animal and agricultural drainages.Someof the pollutions are undecadence , like polop andMercury, and plastices. That we should reducethem in water,In this reseach two samples of mineral waterfound in northern Mahabad, west Azarbaigan, withhardness of 36 , 42 mg/l(CaCo3) are investigated.Then, different amount of Ozone gas is injectionin to mineral water and biological and chemicalchanges probed.The used Ozonator can produce 25 mg Ozoneper hourTo determine the amount of Ozone gaswe used iodometry method. In injection of 1.25mg/1 we going complete removal of diatomaceaein sample (1) and up to 99 percent in sample (2).Both had complete removal of chlorophyceae in1.1 mg/1 complete remove of BOD5 sample 1 in1.1 mg/1 Ozone and in sample in are my Ozone.We had 65 percent reduction of COD for injectionof 1.2 my Ozone for sample (1) and 68 percent forsample (2).Complete disinfection is done in both by 0.5 mgper liter.In this method agreeable water is achievedbecause no chemical is used and we don’t need toprovide chemicals. So, we can introduce Ozonetionthe best method forfiltertion water.

Nowadays, the management of environmentalissues such as hazardous waste is not simply atechnical problem, but is confounded by legal,social, political and even ethical considerations.Environmental ethics deals with the moral issuesinvolved in relationships between humans and theworld around us. Due ro the importance of theseissues in our present world, the understanding ofmain principles of environmental ethics and philosophyhas become essential for all specialistswho are working in different fields. The environmentalissues cannot be solved without the helpof all people, specially managers and engineers.The main aim of this paper is to compare differentethical perspectives regarding our environment.In the paper, different ethical perspectives includinghumaisn, biocentrism (life-centered), ecocentrism(eco-centeric), and utilitiarinism are brieflyexplained. In addition, the religious view pointsregarding the environment are briefly discussed.Humanism claims that human society is uniquebecause of out intelligent, foresight and creativityand on the other hand, eco-centrism claims that allecological processes and systems have intrinsicvalues and rights regardless of their usefulness.Furthermore, the importance and role of the codesof Ethics for engineers, which are adopted by severalprofessional associations, are described in thepaper.

Earthquaks in urban areas produce large volumes ofdebris that delay the recovery and response phases.Therefore, debris management and debris removalunder the framework of recovery programs are soimportant. International experiences have shownthat in recovery phase, large amount of wastes canbe recycled and reused. So, necessary constructionmaterials can be provided and the amount of debrisdelivered to landfills and environmental problemswill be reduced. However recovery and responsephases should be done with proper debris management.In this paper some of the problems involvedin earthquake debris are considered and appropriatesolutions are discussed.