نتایج جستجو برای: معماری nmr

تعداد نتایج: 68192  

Journal: :Analytical sciences : the international journal of the Japan Society for Analytical Chemistry 2007
Chul Won Kwak Dong-Ho Choung Sung Ran Min Suk Weon Kim Jang R Liu Hoeil Chung

The utility of infrared (IR) spectroscopy for the determination of strawberry ripeness has been successfully demonstrated. Transmission IR spectra were collected using dried liquid extracts from strawberry flesh. The overall IR feature provided fairly noticeable differences, and the ripeness stage was clearly identified using principal component analysis (PCA). Although all of the extracted com...

Journal: :iranian journal of pharmaceutical research 0
abdul majid ayatollahi phytochemistry research center and school of pharmacy, shahid beheshti university of medical sciences, tehran, i.r. iran. seyed mohammad zarei department of pharmacognosy, school of pharmacy, shahid beheshti university of medical sciences, tehran, i.r. iran. arash memarnejadian department of hepatitis and aids, institute pasture of iran, tehran, i.r. iran. mustafa ghanadian department of pharmacognosy, isfahan faculty of pharmacy, isfahan university of medical sciences, isfahan, i.r. iran. mohammad heydarian moghadam department of audiology, school of rehabilitation, shahid beheshti university of medical sciences, tehran, i.r. iran. farzad kobarfard department of medicinal chemistry, school of pharmacy, shahid beheshti university of medical sciences, tehran, i.r. iran.

phytochemical investigation of the aerial parts of euphorbia erythradenia bioss. (euphorbiaceae), one of iranian endemic euphorbias, with particular attention to triterpene constituents, using methanol solvent extraction was carried out. five known triterpenes, including four cycloartanes and oleanolic acid, were isolated for the first time and identified using nmr and mass techniques. anti hiv...

Journal: :iranian journal of pharmaceutical research 0
yucel kadioglu department of analytical chemistry, faculty of pharmacy, ataturk university, 25240, erzurum, turkey. alptug atila department of analytical chemistry, faculty of pharmacy, ataturk university, 25240, erzurum, turkey. mehmet gultekin department of chemistry, faculty of science, ataturk university, 25240, erzurum, turkey. nurdan alcan alp department of chemistry, faculty of science, ataturk university, 25240, erzurum, turkey.

the forced degradation study of lidocaine hcl was carried out according to the ich guideline q1a (r2). the degradation conditions were assessed to be hydrolysis, oxidation, photolysis and dry heat during 24 h, 48 h and 72 h and then the samples were investigated by gc-fid method and nuclear magnetic resonance (nmr) spectroscopy. according to these results, the degradation products were not obse...

Journal: :international journal of nano dimension 0
mehrnoosh khaleghian department of chemistry, islamshahr branch, islamic azad university, tehran, iranسازمان اصلی تایید شده: دانشگاه آزاد اسلامی علوم و تحقیقات (islamic azad university science and research branch) fatemeh azarakhshi department of chemistry, varamin-pishva branch, islamic azad university, varamin, iranسازمان اصلی تایید شده: دانشگاه آزاد اسلامی علوم و تحقیقات (islamic azad university science and research branch)

in this study, b12n12 nano ring has been selected because it consist of four 6-side rings and polar bonds b-n which in comparison with non-polar bonds c-c, is more suitable for the study of the absorption of other compounds. so reactivity and stability of benzene alone and in the presence b12n12 nano ring field checked. to determine the non-bonded interaction energies between benzene and b12n12...

Journal: :international journal of nano dimension 0
ashraf sadat ghasemi department of chemistry, payame noor university (pnu), p.o. box,19395-4697, tehran, islamic republic of iranسازمان اصلی تایید شده: دانشگاه پیام نور تهران (payame noor university) ehsan binaeian chemical engineering department, qaemshahr branch, islamic azad university, qaemshahr, iranسازمان اصلی تایید شده: دانشگاه آزاد اسلامی علوم و تحقیقات (islamic azad university science and research branch) habibollah tayebi textile engineering department, qaemshahr branch, islamic azad university, qaemshahr, iranسازمان اصلی تایید شده: دانشگاه آزاد اسلامی علوم و تحقیقات (islamic azad university science and research branch) yasna modanlou jouybari department of chemical engineering, qaemshahr branch, islamic azad university, qaemshahr, iranسازمان اصلی تایید شده: دانشگاه آزاد اسلامی علوم و تحقیقات (islamic azad university science and research branch)

adsorption of co2 on the surface of single-wall zigzag (5,0) and armchair (4,4) carbon nanotubes (swcnts) were studied through using density functional theory (dft) calculations. optimizations of geometric were performed at the b3pw91 level of 6-311++g** method standard basis set using gaussian 03 package of program [1]. structural models were optimized and adsorption energies, band gap, charge...

Journal: :journal of physical and theoretical chemistry 0
mehrnoosh khaleghian department of chemistry, islamshahr branch, islamic azad university, islamshahr, iran fatemeh azarakhshi department of chemistry, varamin-pishva branch, islamic azad university, varamin, iran masoome sheikhi department of chemistry, gorgan branch, islamic azad university, gorgan, iran

to investigate non-bonded interaction of phenanthrene and bn nanostructure, geometric structure of phenanthrene and b12n12 nano-ring with b3lyp method and 6-31g* basis set are optimized by using ab initio gaussian quantum chemical package. the main purpose of this study was to evaluate changes of electronic properties of aromatic compound in presences nano ring field. therefore reactivity and s...

Journal: :iranian journal of basic medical sciences 0
mehrdad iranshahi department of pharmacognosy and biotechnology, biotechnology research center, school of pharmacy, mashhad university of medical sciences, mashhad, iran seyed ahmad emami department of pharmacognosy and biotechnology, school of pharmacy, mashhad university of medical sciences, mashhad, iran meysam mahmoud-soltani department of pharmacognosy and biotechnology, school of pharmacy, mashhad university of medical sciences, mashhad, iran

objective during the last three decades sesquiterpenoid lactones have emerged as one of the largest groups of plant products with over 3000 naturally occurring substances known. the genus artemisia characteristically contains this biologically active type of secondary metabolites. with respect to increasing interest in the cytotoxic, antibiotic, phototoxic and antineoplastic activities of sesqu...

Journal: :Inorganic chemistry 2013
Takaaki Tsuji Naoto Kuwamura Nobuto Yoshinari Takumi Konno

A mononuclear platinum(II) complex with two monodentate-S H4tg(-) ligands, [Pt(H4tg-κS)2(bpy)] (1), was newly synthesized by the reaction of [PtCl2(bpy)] (bpy = 2,2'-bipyridyl) with NaH4tg (NaH4tg =1-thio-β-d-glucose sodium salt) in water. Complex 1 reacted with additional [PtCl2(bpy)] in water to give an S-bridged dinuclear complex, [Pt2(μ2-H4tg-κ(1)S:κ(1)S)2(bpy)2](2+) ([2](2+)), in which a s...

Journal: :Journal of the American Chemical Society 2013
Yun Ma Craig E Stivala Ashley M Wright Trevor Hayton Jun Liang Ivan Keresztes Emil Lobkovsky David B Collum Armen Zakarian

A combination of X-ray crystallography, (6)Li, (15)N, and (13)C NMR spectroscopies, and density functional theory computations affords insight into the structures and reactivities of intervening aggregates underlying highly selective asymmetric alkylations of carboxylic acid dianions (enediolates) mediated by the dilithium salt of a C2-symmetric chiral tetraamine. Crystallography shows a trilit...

Journal: : 2022

بناهایفرم مفهومی پویا و لغزان است که از هریک گفتمان‌های مختلف معماری تلقی متفاوتی آن به‌دست آمده است. در این مقاله با هدف بازاندیشی مفهومِ فرم گفتمان معاصر، به تبیین زیربنای نظری اقتضائات قابلیت پرداخته شده بدین منظور نخست برخی نیروهای بنیادین مؤثر بر تحول مفهوم دوران معاصر شناسایی شده‌اند؛ سپس به‌مثابة تلقی‌ای پاسخ‌گویی ذکرشده را ممکن می‌کند، معرفی گردیده است؛ ادامه حضور طریق بسط نوشتار مسیر مع...

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