مهدی عبداللهی

Water stress is one of the most important abiotic stresses that harms the growth of plants in arid and semi-arid regions. Plant traits reflect their response and adaptation to environmental changes, which play an essential role in predicting various environmental effects on plants and plant processes. In order to investigate the effect of biochar on the morpho-physiological characteristics of the species (Kochia prostrata L.) in water shortage conditions, a factorial experiment was conducted in the form of a completely randomized design with three replications in greenhouse condition. Drought stress treatments included four levels (25, 50, 75, and 100% of the field capacity), and biochar treatment included four levels (control, 5 g, 15 g, and 30 g). Morphological traits (plant height, root length, aerial biomass weight, and root biomass weight) and physiological traits (photosynthesis, plant water potential, stomatal conductance, and transpiration) of the target species were assayed under drought and biochar treatments. Results showed that the interaction effect of drought stress and biochar on all characteristics except for plant height was significant. Moreover, the main effect of drought stress on all characteristics except for photosynthesis and water potential and also the main effect of biochar on all characteristics except for root length) were significant. The treatment with 30 grams of biochar caused an increase in morphological characteristics (root length, plant height, and plant biomass) by 22%, 36%, and 50%, respectively, compared to the control; this treatment also caused a significant increase in photosynthesis and stomatal conductance by 107% and 32%, respectively compared to control. According to the findings, the biochar treatment of 15 grams resulted in a better performance and can be suitable to increase the efficiency in the species under study. The results obtained from this research can be an essential step toward the practical use of biochar in restoration and improvement of rangelands.

Regarding the analysis of voluntary action, there are two general attitudes in Western philosophy: causal explanation and non-causal rational explanation. The first view has been the classic and common theory in the history of Western philosophy and thought, but the second has been formed in the contemporary century. According to the first view, the inner elements of the agent, i.e., desire, intention and belief, have a causal relationship with his action, and the explanation of the action based on them is an example of causal explanation. John Searle, a famous contemporary philosopher who defends the second view, lists six assumptions for the first theory and criticizes them. Based on the words of Searle and other proponents of the first view, this article explains, rationally analyzes and evaluates Searle's six assumptions and his criticisms.The mentioned assumptions are: the causality of beliefs and desires for rational actions, rationality as following certain principles and rules, rationality as a separate cognitive faculty, weakness of will caused by disturbance in the psychological antecedents of the action, denial of desire-independent reasons for action and realization of rationality in the assumption of consistent collection of previous desires. Searle believes that these assumptions are incomplete. Some of Searle's criticisms and his positive views are debatable, including that the agent himself is the cause of action, not his beliefs and desires, and that Searle's idea of the desire-independent reason is incomplete and there is a desire in this kind of reason. The rationality includes primary goals and beliefs.

Lignin-based adsorbents are one of the common materials for removal of heavy metal ions in wastewater treatment and the adsorption of metals extracted in mines. Therefore, it seems that industrial lignin and its carboxymethylated derivative are able to adsorb zinc and copper cations from aqueous solutions under different operating conditions.

Firs, industrial lignin was carboxymethylated by reacting with sodium chloroacetate. After carboxymethylation of lignin, the characterization tests including FTIR spectroscopy, 1H NMR spectroscopy, acid-base titration, pHpzc (pH point of zero charge) and zeta potential tests were performed. Concentration of ions in aqueous solutions was determined by atomic adsorption technique.

The results of structural characterization tests showed that the reaction of lignin with sodium chloroacetate removed the aromatic hydroxyl groups of lignin, while the concentration of carboxyl groups increased. Thus, it was found that lignin was carboxymethylated successfully. The results of zinc (II) and copper (II) ions adsorption showed that the maximum adsorption of copper ion in comparison with zinc ion occurs in the presence of the modified industrial lignin adsorbent at a pH close to 4. The kinetic study results showed that the adsorption of both ions follows a pseudo second-order model. In the isotherm studies, the Sips model showed the best performance for both the industrial and modified lignin samples. Maximum adsorption capacities for the zinc and copper ions by carboxymethylated lignin were observed to be 0.25 and 0.37 mmol/g, respectively, showing a significant improvement in comparison with unmodified kraft lignin. However, selectivity of the copper ion decreased in contrast. This improvement could be mainly attributed to the significant increase in active sites on carboxymethylated lignin.

The modern spirituality is a theory that has been proposed in recent decades by some Iranian modernist intellectuals. According to this theory, religious spirituality has lost its effectiveness for modern man and has caused him suffering and confusion. Based on the modern rationality, this theory seeks to provide a spirituality commensurate with the needs of modern man. In any case, emphasizing one of the fundamental issues of philosophy of religion (the relationship of reason and religion) and since the legitimacy of any intellectual and philosophical approach depends, at least, on having an internal coherence between the components of its theory, this paper tries to analyze the theory of modern spirituality from the point of view of internal coherence and harmony between the components. Using a descriptive-analytical and desk-research method, and presenting numerous pieces of evidence - such as refusing devotionalism, the unprovability of religious claims and etc. we conclude that, the modern spirituality has major drawbacks and ambiguities in this regard.

The aim of this study was to produce protein isolates from rainbow trout (Oncorhynchus mykiss) and to investigate its nutritional, structural, functional and sensory properties. Fish protein isolates were produced by pH change method using alkaline and acidic pHs (2.5, 3.5, 11 and 11.5). The extracted proteins were evaluated for nutritional value, and functional properties, sensory properties, color, and structural changes of proteins. The extracted proteins showed relatively high nutritional value in the amount of essential amino acids. The solubility, gelling and foaming capacity of the proteins depended significantly on its extraction pH. So that the percentage of solubility and foaming capacity of proteins extracted under alkaline conditions showed a higher rate than acidic conditions while the least gelation concentration was related to pH 11.5. Examination and comparison of color (L, a, b and whiteness) and sensory properties of isolated proteins showed that proteins at acidic pH had a brighter and whiter color and better sensory properties than those from alkaline pH. The change in pH caused extensive protein degradation as shown by FTIR and SEM. The above results showed that the protein isolated from rainbow trout waste has good functional and nutritional properties in alkaline conditions, while the sensory properties and color of acidic conditions showed better results

In this research, the effects of various molar amounts of Tl2O3 addition (x= 0, 0.1, 0.25, 0.5, and 1.0) on microstructure and electrical properties of high-voltage SnO2 varistors were investigated. According to XRD and FE-SEM results, the presence of Tl2O3 was detected as secondary phase in samples which their x values are higher than 0.25. By Tl2O3 addition from 0 to 1%, the grain size decreased from 4 µm to 2.3 µm which it is resulted from a grain growth suppression induced by secondary phase based on Zener mechanism. The best non-Ohmic properties with the nonlinear coefficient of 15.1 and the leakage current density of 95 µA/cm2 were observed in samples doped with 0.5% Tl2O3. Furthermore, the breakdown electric field of this sample was 532 V/mm. Further addition of Tl2O3 had no considerable effect on nonlinearity of samples, but it increased the breakdown electric field of samples through the reduction in grain size.

It is very important to control the process of production of floor tiles to achieve the proper properties. In this study, the effect of sintering temperature on densification behavior and mechanical properties of the floor tile was investigated. For this purpose, specimens prepared with the conventional dry pressing method and sintering was performed in the range of 900 to 1200 °C for 2 hours. According to X-ray analysis, quartz and mullite phases were identified as the main phases in the floor tile bodies. Maximum density, linear shrinkage and compressive strength were obtained for the specimen sintered at 1150 ºC, and this sample had the lowest porosity (0.5%) and water absorption (0.3%). The results showed a sharp decrease in the density and compressive strength of samples sintered at 1200 °C. The existence of porosity and cracks in the microstructure of this sample could be attributed to the oversintering phenomenon. According to the results of this study, a linear relationship between the compressive strength and density of samples can be established, which indicates a strong dependence of compressive strength on the density. The high abrasion resistance of the sample sintered at 1200 °C could be due to its glassy surface.

After the terminology of unity and monotheism and referring to the kinds of the unique, this article explains the viewpoints of Islamic philosophers and the content of religious texts about the unity of Divine Essence. All Islamic philosophers consider the instance of necessary being as unique, and believe that the other instance of necessary being is impossible. But they disagree in the hypothetical examples of necessary being. Previously they believed in numerical unity, but finally they arrived at the theory of the true and real unity of God. And thus they have approached the mystical personal unity.
In Islamic narrations, the numerical unity of God has been negated. The Holy Quran, by describing the unity of Allah Almighty with overwhelming (قهاریت), expresses the fact that the unity of Allah Almighty is such that it does not leave room for a presumption of the other.

In order to improve the physical and mechanical properties,reduce permeability to water vapor, antimicrobial properties and increase hydrophobicity, Salvia officinalis essential oils was combined with the chitosan-tragacanth-clay film. The combination of nanocomposite with three levels of S. officinalis essential oil (1, 1.5 and 2%) in order to choose the best coverage for using in the maintenance of rainbow trout were studied. The best properties of film (Mechanical and antibacterial properties and water absorption)were showed in1.5 % S. officinalis essential oil in combination with nanocomposite. Samples coated with this bionanocomposite, showed the lowest amount of total bacterial loadand phsycrotrophic bacteria when compared to the control during 16 days storage period (p<0.05). According to the results, the combination of chitosan-tragacanth-clay withS.officinalisessential oil, can improve the physical and mechanical properties of chitosan in the film, moreover it can improve its ability to seafood preservation like trout.

Cutaneous leishmaniasis is one of important diseases that is endemic in some areas in iran. Leishmaniasis causes by leishmania parasite and can transmit by sand fly. The aim of this study was report of a cutaneous disseminated leishmaniasis case caused by corticosteroid injection after incorrect microscopic diagnosis. Patient was a 55 years old man who referred to the physician by a painful and wet papule on nose skin. The initial diagnosis of lupus was considered. Prednisone as a corticosteroid had been injected by physician and after a few months several painful nodular and papular lesions were appeared on patient's face, so that the simple cutaneous lishmaniasis became a Cutaneous disseminated leishmaniasis. It should be noted that the immune system of patient was normal. The patient's hom is an endemic area of the disease and the patient's wounds can be suspected of contamination with leishmaniasis. For this purpose, the patient was introduced to the laboratory and Giemsa sampling and staining were carried out. After sampling and microscopic examination leishman bodies were observed in the all samples of wounds. lishmaniasis was diagnosed and then systemic treatment with glucantime was initiated immediately. It is proposed that in negative clinical diagnosis, the microscopic exam and high sensitive standard molecular detection tests, such as quantitative and qualitative PCR can be useful.

In this study, the physical and mechanical properties of tragacanth film incorporated with different antioxidant compounds including Hypericum perforatum extract, Ferulago angulata extract and vitamin C 25% (w/v) were studied. Adding Hypericum perforatum extract, Ferulago angulata extract and vitamin C reduced the moisture content and the solubility of the tragacanth film (p<0.05). The lowest amount of the solubility was observed in the tragacanth film containing vitamin C (51.59%) and Hypericum perforatum extract (52.05%). The amount of water vapor permeability (WVP) decreased in the tragacanth film containing vitamin C (1.68±0.06×10-7 gs-1m-1Pa-1 ), and in the films containing extracts increased significantly (p<0.05). Adding both extract and vitamin C to the tragacanth film decreased the mechanical properties of the film. Also, the lowest amounts of opacity were observed in the tragacanth film and tragacanth film containing vitamin C 1.72 and 0.98, respectively (p<0.05). The lowest amount of light transmission was observed in the tragacanth film containing Hypericum perforatum and Ferulago angulata extract (p<0.05).

Travel habits play a key role in choosing travel mode in a way that Structuring and guiding the user intentions based on the collective interests lead to an organic formation of urban transport planning capacities. The aim of this article is to identify the Permanent pattern in using private and public modes of transport, so the transport behavior of Tabriz can be planned. For this purpose, the cluster method has been used to classify travellers based on habit index or frequency of particular travel model. Methodology of the article is descriptive, analytical and survey. Data was collected in the form of questionnaires and obtaining comments in relation to public relocation in Tabriz. The samples were estimated randomly using Cochran formula for 1100 people in 166 traffic area of Tabriz as one-step cluster sampling, then analyzed through multivariate variance tests. According to research findings, seven patterns of travel choice mode were identified, among them, users with the ability to change the travel mode and public transport users are substantial clusters which show different behaviors and features compared to other clusters. Therefore, this idea is confirmed that different patterns of travel mode may be directed towards various methods for effective transport plans.

Hypothesis: After cellulose, lignin is the most abundant natural polymer in the world. The chemical modification of lignin is the best way to improve its performance in the synthesis of the chemicals and polymeric materials. Among monomers employed in modification of the lignin, acrylamide (AAm) increases the highest yield in graft copolymerization reaction.
A native lignin was extracted from its black liquor derived from paper-making processes by precipitation with HCl, and then purified by dissolving in tetrahydrofuran (THF). Chemical modification of the lignin with acrylamide monomer was investigated in the presence of different initiators including hydrogen peroxide (H2O2)/calcium chloride (CaCl2), H2O2/Fe(II) chloride (FeCl2), ammonium persulfate (APS), potassium persulfate (KPS), KPS/ammonium iron(II) sulfate hexahydrate (AFS.6H2O) and ceric ammonium nitrate (CAN)/HNO3. The graft copolymers were then characterized using Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1HNMR) spectroscopy methods.
Findings: The highest and lowest conversions of AAm monomer in the presence of different initiators used in synthesizing the lignin graft copolymers were observed for the APS and KPS systems to be 94.32% and 77.83%, respectively. Among all initiators used in the present study, only H2O2/CaCl2 redox system led to a 100% grafting percentage at 30°C without any free homopolymer chain, while in the presence of other systems, free homopolymer chains were also formed in addition to the grafted chains. It was found from the results that, the graft polymerization did not proceed in the presence of CAN/HNO3 system.

Focus on the studies of the environmental quality goes back to the 1960s (Connerly & Marans, 1985). The importance of the studies of the environmental quality stems from the measurement and comparison of different housing environmental potentials (Sive & Chertok, 2013), because the measurement and comparison of environmental quality between different areas, not only for researchers but also for residents, workers, managers and policy makers in the public and private sectors are important (Blomquist, Berger & Hoehn, 2001). Although quite detailed studies on environmental quality assessment have been done, the criteria are not developed in the operational programs.
To check the environmental quality of housing, researchers have focused on three main issues. The first issue is to review the relationship between environmental quality of residential areas, welfare and comfort of the inhabitants. The latter focuses on the sense of the inhabitant's satisfaction of the house and its surroundings. Finally, the third issue is related to the environmental quality as a factor in structure of housing price. The literature of this paper is organized according to these three themes. Different researches have used several different methods and indicators for measuring environmental quality and gathered some instances for heterogeneous areas of cities in different time periods (Kamp, Leidelmeijer, Marsman & Hollander, 2003). It is expected proposing new topics for Tabriz metropolis helps to clarify the issue.
Several studies have been conducted regarding to the impact of environmental features on housing prices. Almost all studies in this field were exploratory and focused on the impact of environmental quality on housing prices. Rosiers,Theriault, Kestens & Villeneuve (2007) have defined environmental quality as one of characteristics of neighborhood units and evaluated the impact of these components on housing prices. They found that all the characteristics of neighborhood units are important and make a positive effect on housing prices. In the analysis of distribution of spatial inequalities of access and environmental quality in the metropolitan area of Paris, Palma, Kiarash, Picard & Waddell, (2007) recognized major investments of local-welfare facilities in the housing market. The importance of different environmental attributes associated with housing prices was assessed by Chau, Yung, Leung & Law, (2006) through exploring resident's environmental sense. Also Potepan (1994) concluded that the sale price of housing depends on the amenities associated with the residential area of neighborhood units and despite the high cost of housing, prosperous areas are selected in migration to cities. In a more general perspective, Rogerson (1999) has investigated the impact of absorbing new investments on environmental quality in urban development patterns.
Obviously, the components of the promotion of environmental quality section are of particular importance, which have a positive impact on both housing prices and rental prices. Instead of determining the effect of the price of environmental quality on housing prices, this exploratory study addresses the relationship between the level of environmental quality and housing prices. In this paper, environmental quality is assessed on the basis of environmental and housing characteristics and subsequently a consistent relationship between the level of environmental quality and housing prices is reviewed. The geographical scale of the study area covers 29 neighborhoods in the city of Tabriz. The range of indicators is the level of environmental quality for residential areas that includes both objective and subjective-perceptual indicators. It also ranks the level of environmental quality for residential areas based on geographic levels.
Tabriz metropolitan indicators are a set of multidimensional data over time included the objective and subjective characteristics of the residential environments. In this paper, we selected 28 indicators of environmental quality. These indicators have been classified into six main groups: 1) social indicators, 2) economic indicators, 3) indicators of access, 4) perceptual problems of housing environment, 5) satisfaction of the housing environment and 6) housing characteristics. Social indicators describe the number of persons per household, educational level, population increase and crime rates in residential areas.
Three distinct groups in the metropolitan areas of Tabriz are introduced through the level of environmental quality indicator. In 4 of 29 neighborhoods, the level of environmental quality indicator is greater than 1 and in other sets, the level of 14 neighborhoods is below zero. Also in 11 districts, the environmental quality indicator is between 0-1.
Despite some exceptions, compatibility between environmental quality indicator and sale price of housing in the metropolitan area of Tabriz is remarkable. The three dispersion diagrams provide the evidences of positive linear relationship (slope = 1402/0). However, this analysis is exploratory. To test the intensity of linear relationship between housing prices and the level of the environmental quality indicator, the test of correlation coefficient was used. The test proves that there is a strong and positive correlation between the level of environmental quality indicator and the sale price of housing (The Pearson correlation coefficient is 0.596 and is significant at 0.01). This means that the rising level of environmental quality indicator refers to the increasing prices of housing and vice versa.
Although the correlation coefficient confirms the linear and positive relationship between two variables, it does not reflect the dependency between them. To test the dependency between the level of environmental quality indicator and housing sales prices, the chi-square test was used. The null hypothesis is that the two variables are independent and the variable to be tested against these two variables is dependent. The results of the test proves that these two variables are related to each other (chi-square = 19,432, sig = 0,008); as a result, any change in the level of environmental quality indicator means a change in the price of housing. In addition, the level of probability coefficient is close to 1, which confirms the high dependency between two variables.
The results are: 1. there is a strong and positive correlation between the level of environmental quality indicator and sale price of housing in the metropolitan area of Tabriz 2. The level of environmental quality indicator and the average sales price of the housing are dependent variables.
In this study, the relationship between the level of environmental quality and sale price of housing in metropolis of Tabriz was investigated. The study was conducted in two stages. Firstly, the environmental quality indicator was developed using principal component analysis. Secondly, the relationship between environmental quality indicator and sale price of housing was investigated. Therefore, the correlation coefficient and chi-square tests were used. The results show that there is a strong and positive linear relationship between the environmental quality indicator and the sale price of housing in the metropolitan area of Tabriz and the environmental quality indicator and the sale price of housing are dependent variables.
The results of the study are important for several reasons. The results increase the understanding of the resident's environmental sense and the assessment of the environmental characteristics associated with the residential environment and can be used by decision makers in the public and private sectors, including planners, allowing them to obtain environmental quality indicator at the district level through a comprehensive view. Also, the results indicate that the environmental quality of residential areas can be part of the metropolitan area's competition, because the higher the level of environmental quality indicator in a given area is, the more the housing price in that area will be.
The main limitation of this study is the lack of time series data. The analysis is based on limited data that doesnt provide an opportunity to control and monitor periodically. Therefore, improving the environmental quality indicator based on criteria such as the number of family members, stage of life cycle and duration of residence can be the subject of subsequent studies.

In the recent decades, many articles have been published on the development of lignin and mostly related to the chemical modification of lignin.The direct use of lignin often leads to the synthesis and production of low-value added materials. Hence, chemical modification of lignin not only increases its activity in the reactions but also represents a fine dispersion in the polymer materials. Chemical structure of lignin contains phenyl propane units, originating from three aromatic alcohol precursors of p-coumaryl alcohol, coniferyl alcohol and sinapyl alcohol. The main uses of lignin can be classified into two different methods. In the first method, without chemical modification, lignin is directly incorporated into a polymer matrix to give new or improved properties. In the second method, a large range of polymer materials is synthesized via chemical modification of the lignin. Chemical modification of the lignin has been studied frequently for various purposes. Lignin modification through reaction with formaldehyde, epichlorohydrin, phenol, propylene oxide, propylene carbonate, polyethylene glycol and synthesis of lignin-based copolymers are among reactions studied in the literature. However, this article has been restricted to the discussion on chemical modification of lignin and its use as a source of monomer in the polymerization process.

To understand the background of current travel model is a key issue in the efficient development of urban transport planning, because identifying the mode and factors of travel choice is important to facilitate behavior change. In most cases, the realities of transportation on behavioral approaches are explained better than the logic models. The objective of this paper is to analyze the impact of various factors on the choice of the way of travel for users of personal and public transport. Therefore, conceptual model of travel habits was designed by combining the constraints on the choice of perceptual behavior and planned attitude. Based on the objective, the methodology of this study is of the type of applied-developmental research and also descriptive, analytical and survey method in terms of objective and also, nature and method, respectively. Data were collected through questionnaires and obtaining public comments according to the general displacement in Tabriz city. The sample was estimated using Cochran formula for 1,100 people in 166 traffic area of Tabriz. The results of the Structural equation modeling of travel pattern represent a variance more than 17 percent in private vehicle users and more than 14 percent in public transport users. Other factors such as attitudinal and choice constraints were not so important. Unlike the results of structural equation modeling, attitudinal believes provide possibility of prediction. Accordingly, through binary logistic regression, the willingness of travellers in using public transport was studied, suggesting a significant negative effect of travel habits on the probability of choosing public transportation. Based on the findings of this study, strategic suggestions have been presented aimed at breaking unsustainable driving habits and forming new sustainable habits.

In this research, two types of lignin, i.e. one extracted from industrial waste water of the Iran wood and paper (choka) factory as black liquor and another provided from Aldrich company, were studied. Firstly, the lignin was precipitated from its black liquor by a dilute acid and was then purified by dissolving in tetrahydrofuran (THF). Lignin samples were characterized using Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1HNMR) spectroscopies. It was found from results that the Aldrich lignin has a structure similar with the lignosulfonate while lignin extracted from black liquor does not have a hydrophilic sulfonate group and has a Kraft lignin structure. Using acetylation of Kraft lignin and complementary characterization with 1HNMR spectroscopy, the ratio of hydroxyl functional groups to methoxy groups was calculated to be 1.11 to 1, and amount of the hydroxyl groups was calculated to be 5.91 mmol/g of acetylated lignin, where 53% of the hydroxyl groups is related to the aromatic hydroxyl groups. By having the molecular weight of the Kraft lignin which was obtained from the gel permeation chromatography (GPC) analysis of the acetylated Kraft lignin to be 1260 g/mol, average number of the hydroxyl groups per acetylated lignin chain was calculated to be 7.44.

The presence of molecular iodine was studied in relation the molecular weight and molecular weight distribution of polystyrene, produced by radical poly merization. Radical polymerization of styrene initiated by 2, 2׳-azobisisobutyronitrile (AIBN) was performed at 70°C in the presence of molecular iodine. The synthesized polymers were characterized by gel permeation chromatography (GPC) and proton- nuclear magnetic resonance (1H NMR) techniques. The results of these reactions including conversion data, number-average molecular weight and molecular weight distribution were compared with those obtained for styrene radical polymerization initiated by AIBN at the same temperature in the absence of molecular iodine. It was found that the presence of iodine had a profound effect on the molecular weight and its distribution in the produced polystyrene. This was attributed to the ability of iodine to control the polymerization of styrene initiated by AIBN via reverse iodine transfer polymerization (RITP) mechanism. The polymer produced by this method had a molecular weight of 10600 g/mol with a molecular weight polydispersity index of 1. 3. Due to the importance of induction period in reverse iodine transfer radical polymerization, increasing the temperature to 120°C during the induction period resulted in shorter induction periods and the produced species led to better control of the molecular weight. Also, due to the role of iodine molecules as a radical inhibitor, the presence of a secondary radical inhibitor, i. e. 4-tert-butylcatechol, along with the iodine was investigated in radical polymerization of polystyrene initiated by AIBN. It was observed that the secondary radical inhibitor prevented the consumption of the iodine molecules by the radicals produced from decomposition of the AIBN initiator; therefore, alkyl halides were not produced during the induction period.

In this research, the combination of two levels of tragacanth gum (15 and 30%) on chitosan film 2 % were studied and produced film characteristics checked out. The results are proved the best properties in tragacanth 30% in combination with chitosan. Moisture and solubility was not significantly increased by adding tragacanth to chitosan (p>0.05). There was a significant difference between water vapor permeability of chitosan (control) and composite (p-1 s-1 p-1. Tensile strength of chitosan did not change significantly with the addition of tragacanth (p>0.05) but the lowest tensile strength showed in the composite 15%. Elongation percentage was reduced by addition of tragacanth. Add tragacanth to chitosan did not cause significant changes in its transparency (p>0.05) but the degree of transparency was reduced, so that the lowest transparency was observed in the composite 30%. The results of the present study demonstrated that the addition of tragacanth into the chitosan improve the physical and mechanical properties of this polymer in the film and increase its efficiency for fish packaging.

Lignin is the second most abundant natural polymer after cellulose in the world; and as a cheap, non-toxic and biodegradable material, it is a good alternative to the petroleum-based polyols. Despite researchers’ efforts to identify the structure of lignin, there are many problems which hinder lignin to be accepted as an appropriate monomer and a competitive alternative to the monomers derived from the crude oil for synthesis of polymers such as polyurethane. One of the major problems related to identification of the lignin structure is lack of well-defined protocols and standard. In this paper, a systematic study has been performed to quantitatively identify the functional groups present in the lignin structure using different techniques such as 1H NMR, 13C NMR, 31P NMR, 19F NMR and UV-VIS spectroscopies and titration. The advantages and limitations of each method havealso been discussed. Moreover, the molecular weight and thermal properties of lignin have been determined by a variety of methods.