نتایج جستجو برای: carboxyl groups content

تعداد نتایج: 1125451  

Journal: :international journal of environmental research 0
m. wiśniewska department of radiochemistry and colloid chemistry, faculty of chemistry, maria curie sklodowska university, pland s. chibowski department of radiochemistry and colloid chemistry, faculty of chemistry, maria curie sklodowska university, pland t. urban department of radiochemistry and colloid chemistry, faculty of chemistry, maria curie sklodowska university, pland

purification of drinking and industrial water required usage of high molecular weight polymer to cause flocculation process of dispersed suspension of contaminants. polyelectrolytes, including ionic polyacrylamide are especially appropriate for these purposes, because in this case the suspension stability can be controlled by both steric and electrostatic forces. thus the influence of solution ...

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

the present research study attempted to find out the extent to which two pre-task activities of “glossary of unknown vocabulary items” and “content related support” assisted efl language learners with their performance on listening comprehension questions across two different proficiency levels (low and high). data for this study were obtained from a total of 120 language learners, female and m...

Journal: :جنگل و فرآورده های چوب 0
سحر جلالوند دانش آموخته کارشناسی ارشد خمیر و کاغذ دانشگاه شهید بهشتی حسین کرمانیان سرپرست دانشکده مهندسی انرژی و فناوریهای نوین دانشگاه شهید بهشتی- رئیس پارک علمی تحقیقاتی و فناوری دانشگاه شهید بهشتی امید رمضانی استادیارگروه مهندسی فن آوری تولید سلولز و کاغذ، دانشکده مهندسی انرژی و فن آوری های نوین، پردیس1، دانشگاه شهید بهشتی- معاونت آموزشی و تحصیلات تکمیلی دانشکده انرژی و فناوریهای نوین دانشگاه شهید بهشتی اسماعیل رسولی گرمارودی استادیار و مدیر گروه مهندسی فن آوری تولید سلولز و کاغذ، دانشکده مهندسی انرژی و فن آوری های نوین، دانشگاه شهید بهشتی سحاب حجازی استادیار گروه علوم و صنایع چو ب و کاغذ، پردیس کشاورزی و منابع طبیعی کرج ، دانشگاه تهران

the effect of bleaching with sodium hypochlorite, as one of the most important parameters in obtaining optimal alpha cellulose pulp from cotton linter was studied. in this respect, unbleached cotton linter pulp was prepared from parchin chemical industry co., bleached by hea sequence in ph=9, 11 and 13; and then its chemical structures properties such as alpha cellulose, degree of polymerizatio...

پایان نامه :دانشگاه تربیت معلم - تهران - دانشکده ادبیات و علوم انسانی 1391

the present study aimed at exploring cognitions of iranian english teachers within the context of english for academic purposes (eap). to this end, the cognitions of two groups of eap teachers with respect to their pedagogical content knowledge (pck) and their sense of professional identity (pi) were probed. two language teachers and two content instructors who had at least five years of eap te...

2010
Pedro E. G. Loureiro Eva F. Domingues Dmitry V. Evtuguin Graça V. S. Carvalho

Two industrial elemental chlorine free (ECF) bleaching sequences, D0(EOP)D1(EP)D2 and OQ(PO)DP, are compared with respect to the bulk content of lignin, carboxyl, hexeneuronic acids (HexA), and reducing groups after each bleaching stage. HexA groups contribute significantly to the total content of carboxyl groups, and their degradation during chlorine dioxide bleaching is reflected by a decreas...

2003
Lidija Fras Karin Stana-Kleinschek Volker Ribitsch Majda Sfiligoj-Smole Tatjana Kreze

Complexometric titration was used to determine the carboxyl group content of a series of oxidatively treated (selective and non-selective oxidation) nature cellulose fibers (cotton). The results were correlated with those obtained from the conventional methylene blue method; both methods show an excellent correlation. The progress of the cellulose fibers oxidation was monitored using viscosimet...

پایان نامه :دانشگاه تربیت معلم - تهران - دانشکده ادبیات و علوم انسانی 1389

abstract the primary purpose of this study was to explore the actual practices and cognitions of two groups of iranian eap teachers, i.e. language teachers and content teachers, with respect to teaching reading-comprehension and vocabulary. to this end, tehran university of medical sciences which authorizes both groups of teachers to teach eap courses was selected as the context of the study s...

Journal: :Biochemical Journal 1970

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه علامه طباطبایی - دانشکده ادبیات و زبانهای خارجی 1392

while performance-based language assessment has led to an increased authenticity and content validity in the practice of writing assessment, the reliability of ratings has become a major issue. research findings have shown different reactions by native english speaker (nes) and non-native english speaker (nns) teachers to students’ writings. the focus of this study is on investigating whether i...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید