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Concentrations of lead (Pb) were found in the shells of the oyster Saccostrea cucullata and sediments in May 2010. Samples were obtained at four sites on Qeshm Island, at three sites on Hormoz Island, and at three sites in Lengeh Port along the intertidal coast of the Persian Gulf of Iran. The levels of Pb in sediments and shells were analyzed by graphite furnace atomic absorption spectrophotometer.Mean Pb concentrations in the different sampling stations varied between 613.94 and 0.06 µg g^-1 in the shells of S. cucullata and 180.78 and 0.86µg g^-1 in sediments. Biological effects criteria suggest that Pb concentrations in sediments in three sites from Lengeh Port were higher than ERL (effects range low), but at the all sites were lower than ERM (effects range medium). The present results support the significant differences in shell and sediments’ accumulated concentrations of Pb among sites attributed to input sources of human activities including urban, domestic, industrial, agricultural, shipping and transport, mining activities, and ports and harbors

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Aims: The heritage of early modern architecture in the first Pahlavi era, represents the concept of identity in a new domain which could be attributed to discontinuity of traditional Iranian architecture. Historical architecture in the first Pahlavi era is one of the first attempts made to protract the identity of Iranian architecture in its new shape. The present study was an attempt to retrieve the roots and levels of the historical approach in the first Pahlavi era to explain how identity remains embedded in the modern architectural heritage of this era.

Methods: in the present qualitative study, a descriptive-analytical approach is used to decipher the relationship between the cultural values of modern architectural heritage and the concept of identity in architecture. Using relevant documents, the researcher has tried to explore the trend of architecture formation in the Pahlavi era. By studying library sources, the researcher has also tried to analyze the concept of identity in architecture as well as components affiliated with that. In the next step, an inferential approach is used to investigate the relationship between historicism and identity development in the modern architecture heritage and the results are used to analyze a series of selected buildings associated with the historicism current of the first Pahlavi era.

Findings: Imitative, schematic and conceptual historicism are three components of retrospective approach that are directly correlated with different levels of identity: formal, inferential and semantic.

Conclusion: In the architectural heritage of the first Pahlavi era, Identity is, from a historical perspective, formally transferred through a direct perception and objective adaptation to the attributes of historical architecture in Iran. In the wake of that, another group of buildings was formed, which transferred identity through content representation and as a result of indirect use of Iranian architectural elements and the refinement and abstraction of historical components. Despite emphasizing on similarities, these buildings actually depict a cultural distinction in architectural heritage of this era.

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Toluene is one of the volatile organic compounds and used extensively in industrial processes. Because of toluene effects on human health and environment, it is necessary to implement methods for toluene removal from contaminated air stream. Catalytic ozonation process (COP) is one of the emergent technologies for removal of volatile compounds from air streams. Catalytic ozonation process is an efficient, cost-effective and easy to operate for elimination of organic compounds. One of the main factors directly affecting the VOC removal efficiency and ozone destruction rate is the type of catalyst. In this study the potential of MnO/GAC and MgO/GAC catalysts was investigated for toluene elimination from air stream in the presence of ozone in a lab scale.
The MnO/GAC and MgO/GAC catalysts were prepared by Sol-gel method and then characterized by BET, XRD and SEM analysis. Specific concentrations of toluene in the air were produced by using an air pump and a syringe pump. Phocheck was used to measure the concentration of toluene in gas phase. The effect of retention time (0.5-4 Sec), inlet toluene concentration (100-400 ppmv) and air temperature (25-100˚C) were investigated on catalysts efficiency in the presence of ozone. Ozone dosage (0.1 g/h) kept constant in all experiments. The efficiency of MnO/GAC and MgO/GAC were determined from the breakthrough time and removal capacity and the results were compared statistically.
The BET surface area derived from N2 adsorption- desorption isotherms. From the results the BET surface area of MnO/GAC (1103 m2/g) was greater than that of MgO/GAC catalyst (1082 m2/g). XRD patterns clearly illustrate formation of MgO and MnO crystals on GAC surface. From XRD patterns the peaks at 2θ degrees of 50.3° and 73.8° were related to the MgO crystals. The peaks at 2θ degrees of 42.1°, 51.8° and 70.9° reveal the formation of Mn3O4. The crystallite phase of MgO and MnO was hexagonal and tetragonal respectively. The average size of MgO and MnO crystals was 10 and 12 nm, respectively, calculated using Debby-Scherrer equation. Results of experiments in different retention times showed that breakthrough time of MnO/GAC and MgO/GAC catalysts increased 11.3 and 13.9 times, respectively, by increasing retention time from 0.5 to 4 Sec. When inlet toluene concentration increased from 100 to 400 ppmv, the breakthrough time of MgO/GAC and MnO/GAC columns decreased 65% and 62.2%, respectively. In contrast, removal capacity of MgO/GAC and MnO/GAC was increased 39.1% and 50.4% by increasing inlet toluene concentration from 100 to 400 ppmv, respectively. The efficiency of MgO/GAC and MnO/GAC catalysts was increased 78.3% and 31.5% by increasing air temperature from 25 to 100 ˚C, respectively. These results demonstrates that increase of retention time and bed temperature could positively effect on the performance of MgO/GAC and MnO/GAC catalysts in toluene removal from waste air stream in the presence of ozone.
It can be concluded that MgO/GAC and MnO/GAC catalysts had high potential in VOCs removal from air stream in the presence of ozone. The difference between the efficiency of MgO/GAC and MnO/GAC catalysts was significant (P ≤ 0.05) and MgO/GAC catalyst had higher efficiency than MnO/GAC for toluene removal from waste air in the presence of ozone.

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Transient flows can also be analyzed in frequency domain in addition to time domain. The frequency domain needs no discretization in time and space and this is a one of the advantages of using this domain. Due to this reason, time of computations is reduced. For the frequency analysis of transient flows, the non-linear terms of governing equations and boundary conditions must be linearized. This causes errors in the output of the frequency domain over the exact model of the characteristics method (MOC). Understanding the effect of each non-linear terms separately in the error caused by the frequency domain leads to a greater insight into this domain and provides the basis for future activities to improve this domain. In this study, the individual effects of each non-linear terms of steady friction and valve in the generated error at the frequency domain output are shown by using a Reservoir-Pipe-Valve (RPV) system which has been excited oscillatory. This study has been shown that the effect of the friction term of steady flow on the generated error at the output of frequency domain is negligible, while the nonlinear term of the valve is the main cause of the error in the frequency domain.

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Misunderstanding of reality and belief that something is right, wrong or vice versa is called mistake. Understanding the concept of wrong is not possible simply, because the meaning of right and wrong is relative and temporary. However, what as a mistake requires the performance guarantee, is the event that the belief of the contracting party is not in accordance with the reality. As a result, the mistake in the legal system of Iran and France distorts the will, not the subject of the contract. In Iranian Law, a mistake is sometimes a flaw in the intention and sometimes a flaw in the intention. Based on this, the performance guarantee considered by the legislator is null and void, respectively and in other cases, according to the principle of firmness of contracts, no executive guarantee has been considered for it. In French Law, it sometimes invalidates the will and sometimes impairs it, and in other cases it does not affect the validity of the contract; Based on this, mistakes are divided into obstacles, effective and ineffective, and the guarantee of its implementation is absolute, relative, and in some cases, creating the right of cancellation; An ineffective mistake does not disrupt the contract. The purpose of this article is to explain the nature and position of the mistake by applying the descriptive-analytical method and with a comparative look at the French legal system, and to study its effects in order to provide a suitable solution to solve complex problems that usually occupy the courts of law.