فهرست مطالب ali abbasian

Cellulose is the most abundant natural fiber on earth which considered a renewable source for obtaining environmentally friendly products. The extraction of pure cellulose fibers from lignocellulosic materials requires the application of special extraction methods. However, several challenges arise during cellulose extraction processes. To overcome these problems and make it easier to layer the cell wall and release the cellulose micro and nano structures, in many recent researches, various pretreatment methods are used considering their application. Pretreatment methods can change the structural organization, crystallinity, and polymorphism of cellulose. In addition, it can change the various properties of pretreated raw materials. Therefore, it is very important to know the types of pretreatment methods. Therefore, in the present study, by using the content analysis method and reviewing the most important related works, the types of pretreatment methods necessary for the extraction of cellulose were reviewed and categorized. The results of the present work have been presented for the researchers active in the field of cellulose/polymer micro and nano composites, who need to extract a variety of micro or nano cellulosic structures to advance their research.

In recent years, thin and ultrathin polymer films coated on solid surfaces have been widely used in various industries such as coatings, adhesives, membranes, sensors, etc. However, as the film becomes thinner, the effect of the interfaces increases, so that in thicknesses below 100 nm, the structure and properties of such ultrathin films, including surface properties such as surface free energy, undergo significant changes relative to the bulk of the same polymer. Considering the importance of surface free energy as a controlling factor in many industrial and theoretical phenomena such as adsorption, wettability, lubrication, etc. in polymers, this article aims to review the changes in surface free energy of ultrathin polymer films with changing their thicknesses. Two main factors have been identified in the literatures for surface free energy changes with changing films thicknesses in ultrathin polymer films. First, the long-range forces acting on the chains from the substrate as well as on the droplet placed on the film surface in order to measure the contact angle, and second, the finite size effect that in thicknesses comparable to the gyration radius of polymer chains, along with the intra- and intermolecular entanglements, can strongly affect the conformation of polymer segments as well as the chain mobility in ultrathin films which are slightly screening out with increasing the film thickness.

Common terminology is essential for accurate communication among researchers, scientists, engineers, and other decision makers. To assist manufacturing process characterization, a common understanding of terminology is imperative for efficient and effective communication in industry; it can also facilitate automation and interoperability of software tools. Manufacturing process characterization enables the assessment and improvement of unit manufacturing processes, products, and systems from a sustain- ability perspective. To develop and implement sustainability-related standards and best practices in industry, naming conventions and definitions of common terms are needed. Presently, many terms used are ill-defined, vague, or overlap in meaning. Although there are ongoing standards efforts related to terminology identification and definition, an identified common set is yet to be developed. The objective of this work was to facilitate ongoing standards development efforts by harmonizing the varied array of terms used to describe production processes. As a result of a review of the literature, a concise set of 47 terms focusing on process characterization and able to describe sustainable production was generated; terms unique to individual production processes were omitted. The terms were orga- nized into six categories to define the overarching concepts: Scope, Boundary, Material, Measurement, Model, and Flow. Definitions of the terms were then derived from the literature in sustainable manufacturing and chemical and process industries, process characterization and planning, organization standards, and life cycle assessment and management. The reported terms and definitions are not unique to sustainable production, and could foster wide- spread use of the concepts to improve the economic, environmental, and social performance of industry. In the future, the terminology described could be standardized through international standards orga- nizations.

Common terminology is essential for accurate communication among researchers, scientists, engineers, and other decision makers. To assist manufacturing process characterization, a common understanding of terminology is imperative for efficient and effective communication in industry; it can also facilitate automation and interoperability of software tools. Manufacturing process characterization enables the assessment and improvement of unit manufacturing processes, products, and systems from a sustain- ability perspective. To develop and implement sustainability-related standards and best practices in industry, naming conventions and definitions of common terms are needed. Presently, many terms used are ill-defined, vague, or overlap in meaning. Although there are ongoing standards efforts related to terminology identification and definition, an identified common set is yet to be developed. The objective of this work was to facilitate ongoing standards development efforts by harmonizing the varied array of terms used to describe production processes. As a result of a review of the literature, a concise set of 47 terms focusing on process characterization and able to describe sustainable production was generated; terms unique to individual production processes were omitted. The terms were orga- nized into six categories to define the overarching concepts: Scope, Boundary, Material, Measurement, Model, and Flow. Definitions of the terms were then derived from the literature in sustainable manufacturing and chemical and process industries, process characterization and planning, organization standards, and life cycle assessment and management. The reported terms and definitions are not unique to sustainable production, and could foster wide- spread use of the concepts to improve the economic, environmental, and social performance of industry. In the future, the terminology described could be standardized through international standards orga- nizations.

The oncogenic role of human cytomegalovirus (HCMV) has been recently shown in different cancers like colorectal cancer (CRC). According to the recent immunotherapy approach to target the CMV-expressing tumor cells, we investigated the CMV peptide-stimulated CD8+T cells functions in CRC patients compared to healthy individuals. All sixteen patients and seven controls were CMV seropositive. Blood samples were obtained from patients without chemotherapy and radiotherapy before surgery. Cytotoxic CD8+ T cells were generated using 14-day culture of PBMCs in the presences of CMV peptide epitopes and rhIL-2. In addition to the supernatant evaluations for TNF-α and IFN-γ, the functionality of CD8+ T cells was examined by detecting CD107a and intracellular IFN-γ using flow cytometry. CMV DNA was detected in tissues by Real Time PCR. CMV DNA was found in 31% of tumor tissues, while it was not seen in the adjacent non-tumor tissues. There was a close association between CMV in tumor tissue and tumor grade. Surface expression of CD107a and intracellular IFN-γ in CMV-stimulated CD8+T cells and the level of IFN-γ production in patient and control groups increased significantly after culture. The number of functions increased in patients (p<0.05) and healthy individuals after culture. Followingstimulation, expressions of CD107a and intracellular IFN-γ were elevated in tumor CMV positive patients while the TNF-α secretion was decreased. In vitro stimulation of PBMC in the presence of CMV peptide epitopes and IL-2 can be an applicable method to generate cytotoxic CD8+ T cells in CRC patients for future T cell therapy.

Proteins in the role of plastic have great importance for environmental reasons. Recently, pea protein plant proteins have been considered. pea protein due to the low cost of genetic modification in commercial species and its relatively low sensitivities are considered. In this study, pea protein was introduced to investigate the interactions of pea isolates from pea protein isolates. Studies showed that the type of plasticizers and pH had no effect on the transparency of the films. In the study of the transparency of the bioplastics obtained from pea protein, the increased time for molding was reduced, while the increased molding pressure increased the transparency of the biopolymer. In the study of mechanical properties of pea protein films, thermal isolation was more potent, more elastic and more elastic than the films.pea protein films also showed higher tensile strength and elongation modulus and lower stamina values ​​compared to pea extract films. The increase in time and molding pressure increased the failure strain, while the modulus did not change significantly. In the heat analysis, pea protein glass transition temperature was observed at about 100 ° C, which was increased by increasing the ratio of pea / glycerol chicken as a result of the plasticizer effect to lower values.

In Iran, despite various attempts to increase recruitment of female blood donors, women include less than 10% of the blood donors.
The purpose of the study was to evaluate impact of face to face education via TTT model on people’s willingness to donate blood specially women. A field trial study was designed based on face to face educational plan for population in 22 municipally regions of Tehran (capital of Iran) from March 2010 to February 2011.
Total number of volunteers in trial 2 was 9178 cases including 2785 females and 6393 males compared with 4074 cases including 454 females and 3620 males in trial 1. Female/male ratio in trials 1 and 2 were 0.13 and 0.44, respectively, (P Overall, the face to face education is an appropriate method for safe blood donor motivation and recruitment.

For screening and selecting healthy volunteer blood donors, it is important how to face with the minor risk factors. In a cohort study during the 2005-2011, minor risk factors for transmission of hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV) among blood donors in Tehran, Iran, were evaluated. Data for the study were obtained from the database of MAK-SYSTEM International Group. Odds ratio and relative risk were calculated. To calculate the incidence among repeated donors, the number of seroconverters was divided to person-years at risk. From 19,044 blood donor volunteers entered the study in 2005, 10,696 people were in the unexposed group (no risk) and 8,348 in exposed group to the minor risk factors. They were followed until 2011. The odds ratio was 2.7 for donors exposed group and 2.9 in cupping, 1.4 in dentistry, 1.5 in endoscopic plus biopsy, and 7.8 in household subgroups. Calculated relative risk for HBV was 6.9 in exposed group to the minor risk factors and 9.9 in cupping subgroup. The results of this study show while in the country, more accurate screening tests such as nucleic acid-based tests (NAT) or polymerase chain reaction (PCR) methods has not been used routinely for blood donors, deferral strategy applying in cases of exposure to minor risk factors, especially in the cupping exposed cases, is essential.

Hepatitis B (HB) vaccination is the most effective measure for preventing hepatitis B virus (HBV) infection and its consequences. HB vaccination has been a part of the Expanded Program on Immunization (EPI) of Iran since 1993. To extend HBV immunization, mass HBV vaccination was planned for adolescents born during 1989-1992.. The aim of the present study was to assess the prevalence of HBV infection in Tehran blood donors after implementing national HB vaccination program..Patients and Prevalence of HBV infection was determined in all of Tehran blood donors born during 1989-1993 as cases and the ones born during 1986-1988 as controls. All the participants were recruited after medical interviews. Serum samples taken from the participants as well as other blood donors were tested according to the IBTO standards for hepatitis B surface antigen (HBsAg). Initially, positive samples were tested with appropriate confirmation methods. Statistical comparisons were performed using chi-square test. Prevalence estimates were age-adjusted by the direct method for comparisons across subgroups.. The prevalence of HBV infection was 57/100 000, 350/100 000, and 265/100 000 among accepted blood donors born during 1989-1993 (cases), 1986-1988 (nonconcurrent controls), and 1989-1993 (concurrent controls), respectively. The prevalence of HCV infection in the same group of blood donors was 28/100 000, 38/100 000, and 31/100 000, respectively.. HBV prevalence was significantly lower among blood donors born during 1989-1993, which reflected the positive impact of EPI program and extended mass vaccination against HBV..

Background Deferral for travel to malaria-endemic areas has excluded many blood donors in the Iran. To determine the effect of these deferrals on blood availability and safety we designed this study. Materials and Methods In cross sectional and retrospective study deferred donors due to malaria related risk factors from 2005-2010 in Tehran Blood Transfusion Center were sampled to enroll for analysis. Data were extracted from MAK data base by two different grouped keywords. 2827129 record of blood donor volunteers were surveyed for the study. Results 23462 out of all volunteers were deferred due to malaria`s risks from 2005-2010 in Tehran Blood Transfusion Center. The most frequent deferral causes related to malaria was shown travel to malaria endemic areas. The trend of deferral volunteers due to malaria''s risks was shown descending pattern after relaxing application of the present guideline for travel to very low-risk areas such as Karbala. Conclusions We estimated that the wastage of more than 7000 units of blood were prevented annually by accepting volunteers who travelled to very low malaria''s risk areas، but according to other similar studies it seem wiser to defer them for a short period (e. g. 3 months)، instead without deferral period. If cost permits، The introduction of a malarial screening test in the assessment of malaria''s risk blood donor eligibility would be an ideal strategy.

Different activator systems containing zinc oxide, zinc stearate, calcium oxide, thiodiglycol metal complexes and nano-zinc oxide were applied for sulphur vulcanization of NR/SBR blend. The systems were chosen in order to have better dispersion in rubber matrix, better metal ion release in vulcanization process and lower zinc content. The cure characteristics and physicomechanical properties were investigated. Results showed that zinc oxide could be reduced from 4 to 2 phr in the formulation, without any detrimental effects on properties. Zinc stearate was not a good activator but it could be employed in combination with zinc oxide to improve tensile properties. Calcium oxide did not show satisfactory results. Zinc complex of thiodiglycol was an acceptable substitute for zinc oxide due to better dispersion in rubber matrix and better ability for zinc ion release. Zinc content could be reduced to about 4.5 mmol per 100 g of rubber by using this complex. Calcium complex of thiodiglycol was not a good choice either and showed detrimental effects on properties. Application of nano-zinc oxide did improve abrasion and tensile properties due to better surface effects. An alternative mixing method which was used to improve the zinc oxide and nano-zinc oxide dispersion was good and showed better abrasion and tensile properties. The results are presented as patterns to achieve the desirable properties.

The stratification behaviour of different thermoplastic acrylic copolymers with one epoxy resin and its different curing agents were studied. Xylene and methyl isobutyl ketone were used as solvents of the system. Films with different thicknesses (200, 400, and 800 micron) were applied with a film applicator. Also the effect of epoxy gel time with different curing agents was tested. The results showed that coating stratification was thickness dependent, so that in higher thicknesses and the same compositions more stratified films was obtained. In addition, reduction of gel time of epoxy composition showed untraceable effect on stratification, although long duration of curing has important effect on stratification. The reaction rate of curing agent regardless of gel time is also important. According to the obtained data, it can be concluded that stratification mechanism is not diffusion dominated and it maybe convection dominated. The effect of substrates (aluminium and glass) was investigated for the coatings, and it is found that normally glass substrate yield more stratified coatings. The IR-ATR spectra showed that low surface free energy component could not be found in the bottom layer of stratified films and most of it migrated to the top surface. Our findings to some extent support the proposed theory of minimum surface free energy of the system, but the thickness dependency, reported in our paper cannot be interpreted by current theories.