نتایج جستجو برای: strength significantly decreased p0001 in general

تعداد نتایج: 17104514  

Journal: :جنگل و فرآورده های چوب 0
یحیی همزه استاد، گروه علوم و صنایع چوب و کاغذ، دانشکدة منابع طبیعی دانشگاه تهران، کرج، ایران رحیم یدالهی کارشناس ارشد، گروه علوم و صنایع چوب و کاغذ، دانشکدة منابع طبیعی دانشگاه تهران، کرج، ایران حسین مهدوی دانشیار، گروه شیمی پلیمر، دانشکدة شیمی دانشگاه تهران، تهران، ایران شادمان پورموسی استادیار، گروه علوم و صنایع چوب و کاغذ، دانشگاه آزاد اسلامی واحد کرج، کرج، ایران

in order to simultaneously improve wet and dry strengths of paper and decrease environmental issues related to the wet strength resins, in this study effect of application method of wet strength additives on paper properties was investigated. wet strength resins were applied in four methods including spraying an aqueous glyoxal solution on to the surface of wet paper, addition of aminated polya...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه سیستان و بلوچستان 1390

abstract the influence of cation?? and anion?? interactions on the strength and nature of n…h hydrogen bond has been investigated by quantum chemical calculations in s-triazine…3hf complex. ab initio calculations were performed at mp2/6-311++g(d,p) level of theory. the natural bond orbital (nbo) analysis and the bader’s quantum theory of atoms in molecules (aim) were also used to elucidate t...

Journal: :journal of computational and applied research in mechanial engineering - jcarme 0
m. jooybari school of mechanical engineering, college of engineering, university of tehran, tehran, iran j. shahbazi karami faculty of mechanical engineering, shahid rajaee teacher training university, tehran, iran m. sheikhi faculty of mechanical engineering, shahid rajaee teacher training university, tehran, iran

in the present study, mechanical properties and low cycle fatigue behavior of a solid-solutionized aa6061 aluminum alloy produced by equal channel angular pressing (ecap) process were investigated. the grain refinement after two passes of ecap significantly increased the yield stress and ultimate tensile stress and decreased the ductility of the alloy. however, the improvement of low cycle fati...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه علامه طباطبایی - دانشکده ادبیات و زبانهای خارجی 1388

the present study was an attempt to conduct a contrastive analysis between general english (ge) and english for specific purposes (esp) texts in terms of cohesion and cohesive devices. to this end, thirty texts from different esp and ge textbooks were randomly selected. then they were analyzed manually to find the frequency of cohesive devices. cohesive devices include reference, substitution, ...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه رازی - دانشکده کشاورزی و منابع طبیعی 1392

the aim of the present study was to determine the in?uence of presence or absence of corpus luteum (cl) on hormonal and metabolites composition of follicular ?uid (ff) harvested from different sized follicles and its relationship with blood serum concentrations in sanjabi ewes. ovaries and blood samples were collected from 60 clinically healthy adult ewes (sanjabi breed) 1–3 years of age in dio...

Journal: :journal of dentistry, tehran university of medical sciences 0
farzin heravi dental materials research center, professor of orthodontics, school of dentistry, mashhad university of medical sciences, mashhad, iran. maryam omidkhoda oral & maxillofacial diseases research center, associate professor of orthodontics, school of dentistry, mashhad university of medical sciences, mashhad, iran. niloufar koohestanian general dentist and research scholar, division of biomedical engineering, brigham and woman's hospital, harvard medical school, boston, usa. tabassom hooshmand associate professor, department of dental biomaterials, school of dentistry, tehran university of medical sciences, tehran, iran. hossein bagheri assistant professor of dental biomaterials, dental materials research center, department of operative dentistry, faculty of dentistry, mashhad university of medical sciences, mashhad, iran. negin ghaffari dental student, university of toronto, faculty of dentistry. toronto, canada.

objectives: the aim of this study was to evaluate and compare the retentive strength of orthodontic bands cemented with amorphous calcium phosphate (acp)-containing and conventional glass ionomer cements (gics). materials and methods: one-hundred-and-twenty mandibular third molars were embedded in acrylic resin blocks with the buccal surface of crowns perpendicular to the base of the mold. the ...

Journal: :تحقیقات مهندسی کشاورزی 0
هادی واله قوژدی دانشجوی سابق کارشناسی ارشد پردیس ابوریحان دانشگاه تهران سیدرضا حسن بیگی بیدگلی استادیار گروه فنی کشاورزی پردیس ابوریحان دانشگاه تهران محمدحسین سعیدی راد استادیار بخش تحقیقات فنی و مهندسی کشاورزی و منابع طبیعی استان خراسان رضوی محمدحسین کیانمهر دانشیار گروه فنی کشاورزی پردیس ابوریحان دانشگاه تهران

the shear strength and shear energy per unit area, as well as the force and energy required for picking flowers, are important parameters in the design and development of harvesting mechanisms. in this study, shear strength and shear energy per unit area of saffron (crocus sativus l.) stems were determined at different bevel angles and shear velocities. the force and energy required for picking...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه شهید بهشتی - دانشکده علوم 1371

we describe here a suitable approach for the synthesis of n-unsubstituted monocyclic b-lactams under mild reaction conditions by the annelation of imines with substituted acetylchlorides. in this method the reaily available phtalimidoacetyl chloride were allowed to react with - dibenzylideneiminotoluene (hydrobenzamide) in the presence of an equimolar amount of triethylamine in refluxing toluen...

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه شیراز - دانشکده زبانهای خارجی 1389

the aim of the present study was to investigate the frequency and the type of discourse markers used in the argumentative and expository writings of iranian efl learners and the differences between these text features in the two essay genres. the study also aimed at examining the influence of the use of discourse markers on the participants’ writing quality. to this end the discourse markers us...

This paper investigated the effects of seawater curing of concrete made by Micro-Nano Air Bubbles (MNAB) on compressive, flexural and tensile strengths of the concrete. This product will be applicable for rehabilitation or repair of coastal RC structures. In this research, the effect of different combinations of concrete ingredients including 0-100, 25-75, 50-50, 75-25, and 100-0 percent ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید