Ali Nemati Babaylou, Mehrnaz Azadi Boyaghchi, Farhood Najafi, Mohsen Mohammadi Achachlouei,
year 2, Issue 1 (Semi-Annual 2016)
Abstract
Making varnishes from diterpenoid resins with the several orders had been common in Iran from 12th Century and it has also been reported in Europe from medieval ages. Identification of these resins in old samples and investigation of their degradations through ageing process have performed by various methods. FTIR spectrometry has always been of interest to researchers because it is cheap, available and it requires little sample material. Ditepenoid resins are classified into two classes: mixture of abietane and pimarane structures resins that include colophony and Venetian turpentine, and resins that are formed from labdane and pimarane structures which involve sandarac and copal types. Abietane structures do not polymerized in the time but labdanes and pimaranes polymerize at a very short time. For this reason, they mostly are used in oil-resin varnishes. These characteristics have led the two classes of resins to operate differently during ageing process and production of degradation products. This differentiation helps to identify to characterize the original structure of resin in the varnish compound in FTIR spectrometry. This article reviews the identification characteristics of diterpenoid resins in FTIR spectrometry and it tries to investigate and introduce every resin characteristics according to their structure from several references. Moreover, identification characteristics of linseed oil is introduced because of its application in oil-resin varnishes. Also, degradation process and its production are also reviewed. Differentiation in chemical structures of diterpenoid resins causes the differentiation of ageing process such the polymerization of labdanes and pimaranes and cross linking in ageing process produce some new functional groups. Also some functional groups are destroyed during ageing. The changes observed in FTIR spectrometry are inclined oxidation and polymerization of varnishes that in turn changes bands intensity related to OH region, especially in 3000 and 3450 cm-1 and carbonyl region bands. Degradation process of resins in solvent and oil-resin varnishes is same but identification of resin characteristics in oil-resin varnishes is difficult because of effects of oil oxidation on varnish spectra after aging process. Also cross links in varnish structure during aging process causes the formation of some new bands in aged varnishes spectra. Degradation products in resints and ambers are to some extent like that of old resins and varnishes because their aging process is same.
Mehrnaz Azadi Boyaghchi, Ali Nemati Babaylou, Azita Mosavi Majd,
year 3, Issue 2 (Semi-Annual 2017)
Abstract
The stains caused by hand contact on books are one of the problems in conservation of historical papers during the cleaning process. These stains are usually resistant and not easily soluble in solvents. Accordingly, it is necessary to know their structure in order to select the appropriate solvent and cleaning method. The aim of this article is to study the structure of stains caused by hand contact in historical papers. These stains are referred to as greasy stains in some texts, and many of them are old, and their abundance in some cases indicates the amount of object using. So, this article tries to answer the question of what is the chemical structure of the hand-caused stains on historical papers. For this purpose, Fourier Transform Infrared Spectroscopy (FTIR) was used to identify the structure of the stains in 20 samples of paper and paper works of Dariush Pebdeni collection in Foulad Shahr- Iran. Before the analysis, sizing material was identified by the classic methods and analysis carried out on the samples with the starch sizing. The results of this study showed that the structure of the stain is composed of sulfur proteins and does not have a fatty structure. The presence of absorption bands associated with NH and CN and the absence of carbonyl bands associated with carboxylic acids and esters shows that stains have proteinous structure and they are non-fatty stains. The absorption bands of the 700-900 cm-1 region can be attributed to out of plan bending N-H, which is combined in amide and amine samples. The strong bands at 1032 cm-1 and 1222 cm-1 can be due to C-N stretching in aliphatic amines. Also, skeletal vibrations of cycloalkanes can also produce a medium to strong adsorption band in the 1030 cm-1 region. The absorption band of the 1363 cm-1 in these samples is also due to N-O nitro in amines and amides, and the absorption band of the 1114 cm-1 region is probably caused by C-O. Absorption bands related to NH and CN, which is seen in the structure of amides and amines, and two specific absorption bands belonging to sulfur compounds (470 cm-1 resulting from S-S and 2518 cm-1 related to S-H) can indicate the protein's stains. Sulfuric amino acids in proteins include cysteine, cystine and methionine. The cysteine loses its hydrogen and, by forming a bond between the two sulfur atoms in the structure of the proteins, conjuncts the polypeptide chains. The presence of peptide bonds in the stain can be demonstrated by a C-N-C related absorption bands in the range of 1160 cm-1 and 1222 cm-1. Also it should be noted that the presence of adsorption bands related to OH stretching in 3440 cm-1 could indicate the oxidation of the product, which could justify the resistance of stains to conventional organic solvents. This absorption band that is usually strong and broad, is observed in all samples and has overlapping with a stretching NH attraction of about 3300 cm-1. Accordingly, a comparative study of the Fourier Transformation Infrared Spectroscopy results of historical samples with animal proteins indicates the similarity of the spectrum of spots with the spectrum of animal glue and gelatin.
Hamid Reza Ghorbani, Samineh Nemati Giv, Hossein Moradi,
year 8, Issue 1 (Semi-Annual 2022)
Abstract
Space Syntax is a structuralist research approach to architecture that makes it possible to understand and interpret the social organization in built environments by studying the phenotype (structure) and understanding the genotype (function). The architectural remains from the past are important indicators in archaeological sites and the most significant findings in applying the space syntax approach. There is little information on the extent to which prehistoric buildings are capable of providing spatial configuration and social organization or the extent to which the space syntax approach can identify, perceive and interpret them in prehistoric and early historic structures and sites. Previous studies, with a few exceptions, have considered the use of the space syntax approach not in prehistoric houses or population areas but the later and contemporary eras. The present paper aims to use the space syntax method, along with observation tools, field studies, documentary investigations, and A-GRAPH and Depth Map software to perform an analytical comparison of spatial configuration and social organization in buildings1 (II and III periods) and 20 (IV period) of Shahr-i-Sokhta. The study examines the indicators of Depth, Relative Asymmetry, Integration, Control Value, and Space Type in terms of communication, access, privacy, and publicity to answer the following two questions: 1. what are the differences in the pattern of spatial configuration in buildings 1 and 20 of Shahr-i-Sokhta? 2. What is the relationship between their spatial configuration and social organization? The analytical-comparative study of buildings 1 and 20 of Shahr-i-Sokhta clearly shows that building 1 has more depth and consequently a higher degree of privacy, which can belong to the aristocrats or a person with high social status. However, building 20 has more movement, integration, and connectivity; thus, it cannot be considered only a completely private building, and it may have been a more public building.
Zahra Nemati, Kamal Addin Niknami, Mohsen Heydari Dastenaei, Ebrahim Roustaei Farsi,
year 9, Issue 1 (Semi-Annual 2023)
Abstract
Ancient sites represent the cultural landscape resulting from the interaction between humans and the environment. They are influenced by a set of geographical, natural and socio-cultural factors. The interpretation and disclosure of environmental information of settlement distribution can provide conditions for a better understanding of the interaction between human and the environment in this era. In this interaction, environmental factors are in a way the geographical and natural substrates play an effective role in the distribution of ancient sites. The purpose of this research is to evaluate the geographical foundations of the Sassanian sites in the highland of Arsanjan. Based on this, six geographical factors were considered as environmental factors or independent variables and the area of ancient sites as dependent variables. To investigate these factors, Arc Gis and SPSS software and quantitative analysis methods of inferential statistics with the Pearson correlation method were used. The results of these analysis determined that Sassanid period sites with a number of natural factors such as moderate to weak dependencies and a number of environmental factors also show a high dependency. This number expresses the relatively high and positive correlation between some geographical and environmental factors and the Sassanid era sites of Arsanjān plain. In the analysis and evaluation of the settlement patterns of Sassanid sites using cluster analysis, four patterns were obtained.
