hamidreza bakhshandehfard

The artifact studied in this paper is a bimetallic sword made of bronze handle and an iron blade, which was excavated from the Tol ancient cemetery, located in Talash city, Gilan province, in 2001 by Mohammad Reza Khaltabari. This research aims to study the technology and pathology of the mentioned object by conducting comparative and archeological studies using the library method, conducting technological studies using the laboratory methods of radiography, metallography, and microstructural observations using a scanning electron microscope (SEM-EDS). The phase analysis of corrosion products was done by X-ray diffraction (XRD), as well as knowing the manufacturing method and identifying the types of damage and corrosion. The result shows that this work belongs to the Iron Age. Also, the tests performed on the two parts of the handle and the blade showed that the material of the iron blade is iron-carbon alloy. The amount of carbon in different parts of the body of blade is not the same and the handle is made of bronze alloy with casting and hammering techniques. It also has a galvanic corrosion effect.

The cemetery of the Pardis Tepe, located in Qarchak of Tehran province, is a valuable historic landmark of the Iron Age which has been discovered in the excavations of these bronze wire objects. Despite the historical importance of the metal objects discovered in Tehran, no independent research has been carried out on the metal objects obtained from this site, in terms of technological and pathological aspects, using laboratory and methodological methods. The aim of this paper was to study a bronze rod found in Tepe Pardis, in terms of species and application, regarding technical questions about elemental combinations and the method of making and technological position of the study area. For this purpose, instrumental analysis methods such as AAS, SEM-EDS were used to identify the alloying technique, the chemical composition of the alloy, and metallography to identify the manufacturing method. Historical studies of the object attributed it to the Iron Age. Based on elemental data analysis, the composition used to make copper-tin alloy objects (bronze) and microstructure analysis by metallography, these objects were made by continuous thermal / mechanical operations. Depending on the results of the XRD test, cuprite, malachite and nantokite compounds were identified in corrosion products. Due to the significant presence of Nantokite, it can be said that the object has active corrosion.

 Some architectural and artistic monuments have been preserved from the city of Bishapur, which was founded in the early Sasanian era by Shapur I. One of them is the remains of a building called the Cruciform Palace. The cruciform plan of the construction is surrounded by huge piers of stone and gypsum, about six meters thick, and its central square is over twenty-two meters long. There are currently no signs of ceiling or roof in situ.Hypothesis: The previous theories about the possible ceiling form of the Cruciform Palace of Bishapur are not based on documentation. The imagined dome over the central square of the Cruciform Plan would be the largest stone dome of that period in Iran. The existence of a dome above this building and its compliance with the conventional dome form of Sasanian architecture is the hypothesis of this research.

The purpose of this research is to find indications that demonstrate the possibility of the existence of the dome and then illustrate the possible authentic form of its structure based on the reliable evidences.

To achieve these goals, a comparative study method was utilized and the samples that were similar in structure, architecture, and historical style were studied. Their dimensions and proportions were examined to obtain a model for the size of piers and spans in the Sasanian domes.

According to the obtained results, the thickness for piers of the palace is consistent with the average size of the selected samples of the Four-Arches constructions in Iran and potentially confirms the existence of a dome over the square section of the cruciform plan. About the height of the dome, the range of results is various and the hypothetical height can be estimated based on the mean measurements.

In recent years, two significant historical sites, Tepe Forodgah and Sangtarashan have been excavated in Khorramabad. Bronze objects explored from both sites exhibit an interesting feature of metal production in terms of shapes and techniques used. Tepe Forodgah was excavated in 2014 and Sangtarashan was excavated during six seasons since 2003. Tepe Forodgah yielded few bronze objects but a large number of bronze objects were obtained from Sangtarashan. In this research, two bronze objects were selected from each historical site and results of the analysis were analyzed and compared concerning their chronological orders. In this research, type of alloy, manufacturing technique, elements and chemical compounds of samples were studied by Scanning Electron Microscopy equipped with Elemental Analysis, Metallography, Computed Tomography and X-Ray Radiography. According to the results, the alloy used in all the objects was known to be bronze and based on the microstructure of the objects, hammering and annealing used in manufacturing technique.

Any historical monument may have lost some fragments due to various factors. The extent of defects, whether in quantity or quality, directly relates to the loss of identity and integrity of the building, and reduces the accuracy of its physical or virtual reconstruction. On the other hand, a lack of understanding of the complete form of a building affects the degree of justification for its conservation. The Mosaic Iwan in Bishapur, which has suffered the named damages, is selected as a case study. The floor mosaic decorations of the iwan were sent to the National Museum of Iran and the Louvre Museum in Paris during excavations and nothing remains of the vault above the room. The lack of understanding of the original form of the building has derailed the protective measures, i.e., supporting walls are constructed regardless of the original form of the building and the location of mosaic floorings. The interpretive-historical strategy based on documentary and visual evidence was selected along with the simulation strategy for the research method. In this research, the current state of the building is compared with existing images of mosaic designs first, the damage caused by the lack of proper understanding of the original form of the building is identified, and then, the possibility and the role of virtual reconstruction in the preservation of the monument and its values are expressed. For this, the damaged architectural elements and decorations were reconstructed virtually. According to the principles of preserving the authenticity of works in a historical site, and that physical reconstruction can lead to the production of imitative and fake pieces, the production of virtual heritage is one of the ways to provide a visualization of the initial form of the building with minimal physical interference. Visualization of the imaginable initial form of a monument guides the main preservation plans. In other words, the outcome of this study is that the virtual reconstruction of the Mosaic Iwan can protect it from damage caused by the lack of understanding of its original form.

The coin is the best material for date detection and understanding the historical and cultural period and recognition of characteristic features of historical periods. In 2014, the archaeological excavations carried out under the supervision of Noori and Javeri in Faizabad historical site. In this excavation, they discovered historical architectural texture of historic village. In addition, they found 50 coins in depth of 2.5 meters. These coins are the most important data in this excavation. The aim on this paper is the technical investigation and readings of the coin line drawing and chemical composition diagnostics, type of an alloy and comparative history. For this purpose, analytical techniques such as SEM-EDS and metallographic and X-ray techniques carried out, then line drawing and pattern recognition were done. The results obtained in the light microscopy studies. Coin levels are covered with crude and rough patina, and in some coins the main surface of the coins was completely destroyed and there was no possibility of retrieval of the designs. Fortunately, in some coins, it was possible to restore relative motifs by means of clearing or reading lines and the motifs of coins with other methods (radiography). The results of metallographic studies in the samples show a mechanical twin structure and etch microstructure indicating a re-crystallization and along with the deformation resulting from the coinage process, as well as twinned lines, some of which are slip lines and appearance changes in the microstructure by radiographic studies and the detection of motifs by the methods of restoration on coins, it was possible to read relative lines and motifs. According to visual microscopic and macroscopic examinations as well as radiographs performed from coins 1 to 6, coins 1, 2 and 3, the motifs were found underneath the layers. In coin 1, a little background from the word “al-Hamdullah” can be seen. Coin number 2 was only seen as a marginal role. In coin number 3, its line is more similar to the Ilkhan coins, and the term Muhammad’s Prophet Muhammad is seen on it. During the reign of Sultan Muhammad, Allah, the servant who converted to the Shiite Shīhāṭāṭīn, Ali Valiallah and the name of the twelve Imams on coins. Unfortunately in coins 7 to 12, the motifs and the line have been lost due to corrosion. In coins 13 to 18, the lines containing the note are seen but not fully readable. From coins 19 to 26, it is only in the coin that the 26 words “Allah” appear on one side of the coin and a Religious claim on another coin. In coins 27 to 40, it is only seen in the coin of the 38th word “la ilaha illa ’llah (there is no god but God), and “Muhammad rasul Allah” (Muhammad is the messenger of God). In coins 41 to 50, the motifs and the lines are unclear. The results of the scanning electron microscopy studies showed that the average of the elements in these 30 points was 11.86% oxygen, 1.28% silica, 0.75% sulfur, 30.5% chlorine , 0.33% iron, 29.2% copper, 33.3% tin and 29.07% lead. Therefore, due to the scanning electron microscopy images as well as the elemental analysis (EDS), the linear analysis show that alloy consist of copper, lead, and tin. From the point of view of pathology, it should be noted that the level of all coins covered with corrosion products was dark green and sometimes with red corrosion, and at the surface of some coins, in addition to the corrosion products covered by the layer Sedimentary and soil.

The objects of the study are two bronze daggers dated back to the late Bronze Age and early Iron Age. They lack any ornaments and there is corrosion and oxidation in their surface. The purpose of this study is to recognize the technological and pathological research on the mentioned objects through comparative and pathological studies and library method, to conduct the technological and pathological research through laboratory method (wet chemistry, radiography, metallography, metal core elemental analysis by Scanning Electron Microscope (SEM), analysis of corrosion by X-ray diffraction (XRD) in order to identify the metal and making techniques and to determine the types of damage, and finally to perform the conservation and restoration of the these objects through the conservation plan.
After studying and conducting experiments mentioned, it was determined that the material of the objects was bronze with carbonate and chloride corrosion. The making methods in these objects is casting and hammering. They were recognized to belong to the Iron Age.

“Kurgans”, which have recently been explored during an archeological excavation in Iran, contain graves where Eurasian used to bury the corps of their dead people. The Kurgans in Jafarabad (in East Azerbayejan, Iran) were excavated by archeologists in 2011.According to the reports of the first phase of the excavations of Jafarabad, a total of 54 bronze objects were discovered the majority of which were ornamental objects.Most of these objects were explored from Kurgan no. 8 of this archaeological site including two bangles. In this research, SEM-EDS, AAS, X-Ray radiography, and metallography were applied to identify alloying composition and shaping techniques. Results showed that the bangles have been made from tin bronze. Based on microstructure, it can be concluded that an alternating operation has applied for shaping these objects. Radiographic images also confirmed the application of hammering techniques in the production of these objects.

Most corrosion inhibitors are toxic and can cause damage to conservators. The aim of this research is to achieve a non-toxic corrosion inhibitor which has good efficacy، is effective and inexpensive، and does not create structural changes، discoloration and deformation on the historical artifact. Nicotiana Tabacum (tobacco) extract consists of alkaloid components and these materials have an important role in controlling corrosion. In this paper، tobacco was selected and extracted، and its function in sodium chloride، 0. 5 M as the corrosion inhibitor was evaluated in historical copper artifacts. Review of literature shows that this compound has not been used in the field of restoration. Electrochemical potentiodynamic tests were used to assess the function of this extract. Using this method، some information such as the potential and rate of corrosion، the slope coefficient of cathodic-anodic polarization and resistance at the concentration of the extract was obtained. Further، weight loss tests were carried out. In these tests، copper coupons were prepared and، after artificial aging by the inhibitor، their performance was controlled. Fail/Pass test was used through Rosenberg test to evaluate efficiency of the inhibitor for controlling the bronze disease on historical samples and the distribution of such disease on the samples was evaluated. Accordingly، optical microscope (OM) and electron microscope (SEM-EDAX) were used and the effectiveness of the inhibitor was evaluated with the help of several indicators. Moreover، for evaluating the rate of glaring and glittering of the surface after using tobacco extract the optical density-measuring was used، and colorimetry method was used for studying the changes in color، brightness and overall patina color of historical artifacts after using tobacco. The results of experiments and studies imply the good performance of tobacco extract against corrosion and it can be argued that this herbal extract is a very good option due to its high effectiveness and the least amount of changes on the chloride patina.

Anabasis Setifera is a native plant of Balochestan-Iran that was used for washing textiles traditionally. In this work, the identification of saponins as a surfactant/detergent in the stems and leaves of this plant was studied. The experiments showed the presence of saponins, alkaloids and phenolic compounds and the absence of tannins and flavonoids in the extracts. Three different methods were used for extraction of active materials from this plant and their physical-chemical properties were compared with each others. The results showed that the yield of extraction was different and as a result, their surface tension properties, and critical micelle concentrations (CMCs) varied. The CMC value of the extracted compounds by traditional method (~33 mg/L) was much lower than those of the corresponding compounds extracted by water or alcohol extractions (~166 mg/L). The extracted compounds with the traditional method had the best properties considering the CMC value and foamability.

In this article، a new non-toxic inhibitory solution extracted from Camellia Sinensis (green tea) and its efficiency in 0. 5 M NaCl are investigated. For this purpose، weight loss methods and polarization dynamics electrochemical methods are used. Also، the evaluation of patina changes in historical samples is performed. For this purpose، optical densitometry on patina، optical microscope (OM)، scanning electron microscope (SEM) and Energy-dispersive X-ray spectroscopy (EDX) are applied. The results show very good inhibitory property of this solution.

In this paper an attempt to looking for a safe, effective and enviromental friendly inhibitory compound. The aim of present work is to study a new corrosion inhibitor for treatment of historical copper artifacts with no changes and damages to patina.On this basis, according to studies, a new non-toxic inhibitory solution extracted from garden sage (Salvia officinalis) and then its efficiency was investigated in 0.5 M Nacl.Electrochemical measurement, weight loss studies were carried out to evaluate the performances of this compound. Next it was used for treatment of bronze diseases in some copper alloy artifacts with regard to treatment policies.Then the evaluation of patina changes in historical samples was performed. For this purpose optical densitometry on patina, optical microscope (OM), scanning electron microscope (SEM) and Energy-dispersive X-ray spectroscopy (EDX) were applied. The results showed good inhibition property of this solution.