lobna.nassr

Lobna Abdel-Mohsen Ebaid Nassr

Professor - Director of Quality Management Unit - Faculty of Science - Sohag University

Faculty of science

Address: Chemistry Department - Faculty of Science - Sohag University

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Prof Dr Lobna Abdel-Mohsen Ebaid Nassr

Prof. of Non-Organic Chemistry

Director of Quality Management Unit - Faculty of Science - Sohag University

 

https://www.researchgate.net/profile/Lobna_Nassr

https://www.scopus.com/authid/detail.uri?authorId=6506216126

https://scholar.google.com.eg/citations?user=XBI3s7IAAAAJ&hl=en

 


2019-04-03 16:00:38
نتيجة اختبار نصف الفصل لمقرر الكيمياء الفيزيائية 222 ك لطلاب الفرقة الثانية (فيزياء و كيمياء) 2018/2019
ابانوب شكرى حكيم سوريال 16 احمد عمر احمد عبد الرحمن 17 اسراء اليمنى السيد اليمنى 16 اسراء عبد اللطيف على عبد الرحمن 22 اسماء على محمد عبد اللاه 17 اسمينة فراج شرقاوى محمد 21 الاء رمضان عبد اللاه حسن 13 اميره اشرف احمد محمود 16 اميره بارح ابراهيم حسن 13 اميره محمود هاشم مراد 21 اميره مسعد الصياد عبد الرحيم ... Read more

2018-12-01 21:18:14
Supplements
For the students in different programs: Check for the supplements related to your courses in the link for each course Especially for the following courses: Transition Metals 311 C, Third year Chemistry program – Faculty of Science Kinetic Theory 321 C, Third year Chemistry program – Faculty of Science Chemical Kinetics 321 C, Third year Chemistry program – Faculty of ... Read more

2018-12-01 14:52:10
Hydrogen peroxide poisoning
HYDROGEN PEROXIDE POISONING Hydrogen peroxide is an oxidising agent that is used in a number of household products, including general-purpose disinfectants, chlorine-free bleaches, fabric stain removers, contact lens disinfectants and hair dyes, and it is a component of some tooth whitening products. In industry, the principal use of hydrogen peroxide is as a bleaching agent in the manufacture of paper ... Read more

2018-12-01 14:40:39
Toxicity of Sodium Cyanide
TOXICITY OF SODIUM CYANIDE sodium cyanide is used often as an industrial reactant in the mining industry to extract precious metals such as silver and gold, this compound can be fatal when improperly exposed. 4Au + 8 NaCN + O2 + 2 H2O → 4 Na[Au(CN)2] + 4 NaOH Typically, victims smell the scent of almonds before fatally succumbing to ... Read more

2018-12-01 11:31:38
توصيف مقرر دراسي
توصيف مقرر دراسي محتويات توصبف المقرر الدراسى بيانات المقرر المستهدف من تدريس المقرر (المعارف و المفاهيم - المهارات ال\هنية - المارات المهنية - المهارات العامة) محتوى المقرر اساليب التعليم والتعلم تقويم الطلاب (الاساليب - التوقيت - توزيع الدرجات) قائمة الكتب الدراسية والمراجع (كتب اساسية - كتب مقترحة - دوريات - ابحاث ...) Read more

2018-11-28 15:57:41 | Keywords aqueous solvent mixtures, high spin, Chelates,
Hydrophobicity, reactivity trends of base catalyzed hydrolysis of some novel high spin Fe(II) Schiff base amino acid chelates in some binary aqueous solvent mixtures: Initial-transition state analysis
Rate constants for the base hydrolysis of bis(naphthylidene alanate)iron (II) (nali), bis (naphthylidene phenylalanate)iron(II) (nphali), bis(naphthylidene aspartate)iron(II) (nasi) (naphthylidene histidinate)iron(II) (nhi), bis(naphthylidene arginate)iron(II) (nari) have been reported in different binary aqueous solvent mixtures at 298 K. The observed reactivity trends are discussed in terms of the hydrophilic and hydrophobic forms of the complexes investigated, as well as the transfer chemical ... Read more

Reactivity trends of hydroxide ion attack on high spin Fe(II) complexes including bromosalcylidene amino acid ligands in some mixed aqueous solvents: Gibb’s free energy of transfer and initial-transition state analysis
The kinetics of hydroxide ion attack on bis(bromosalicylidene alanate)iron (II) (bsali), bis(bromosalicylidene phenylalanate)iron(II) (bsphali), bis(bromosalicylidene aspartate)iron(II) (bsasi), (bromosalicylidene histidinate)iron(II) (bshi), bis(bromosalicylidene arginate)iron(II) (bsari) have been reported in different binary aqueous solvent mixtures at 298 K. The observed reactivity trends are discussed in terms of the hydrophilic and hydrophobic forms of the complexes investigated, as well as the transfer chemical potentials ... Read more

2018-11-28 14:29:32 | Keywords ONO donors, Hydrophobicity, antibacterial,
DNA binding ability mode, spectroscopic studies, hydrophobicity, and in vitro antibacterial evaluation of some new Fe(II) complexes bearing ONO donors amino acid Schiff bases
New series of Fe(II) complexes and Schiff base amino acids have been designed and synthesized from the bioactive ligands by condensation of 5-bromo-2-hydroxybenzaldehyde and aamino acids (L-alanine (ala), L-phenylalanine (phala), L-aspartic acid (aspa), L-histidine (his) and L-arginine (arg)). Elemental analyses, infrared, ultraviolet–visible spectra, as well as conductivity and magnetic susceptibility measurements are used to elucidate the structure of the newly ... Read more

2018-11-28 15:19:28 | Keywords Coumalic acid, base catalyzed hydrolysis,
Kinetics, reactivity, initial-transition state analysis and thermodynamic parameters of base catalyzed hydrolysis of coumalic acid in solvents with different polarities
Base-catalyzed hydrolysis of coumalic acid (COU) in binary aqueous-methanol and aqueous-acetone mixtures has been studied kinetically at a temperature range from 283 to 313 K Moreover, the change in the activation energy barrier of COU from water to water–methanol and water–acetone mixtures is estimated from the kinetic data. Solvent effects on reactivity trends have been analyzed into initial and transition ... Read more

2018-11-28 00:00:53 | Keywords tensides, Initial -transition states, Lobna A. E. Nassr,
Reactivity tracers of the hydrolysis of Fe(II)-bis(salicylidene) complexes: Initial -transition states analysis and enhanced impact of tensides on the kinetic trends
The kinetics of the acid hydrolysis reaction of Fe(II)-bis(salicylidene) complexes were followed under pseudo–first-order conditions ([H+] >> [complex]) at 298 K. The ligands of the studied azomethine complexes were derived from the condensation of salicylaldehyde with different five α-amino acids. The hydrolysis reactions were studied in acidic medium at different ratios (v/v) of aqua–organic mixtures. The decrease in the dielectric ... Read more

2018-11-29 01:09:09 | Chemical kinetics 321 C
Acid / base  effect on an enzym
Deduce the relation between the reaction rate and substrate concentration for an enzym "HE" in both acidic and basic medium. Concerning the following: Kb=[H+][HE]/[H2E+] Ka=[H+][E-]/[HE] 0[E] = [HE] + [HES] + [H2E+] + [E-] Read more

2018-11-29 00:50:41 | Kinetic Theory 321 C
nonideal behavior of Gases
If 1.000 mol of an ideal gas were confined to 22.41 L at 0.0°C, it would exert a pressure of 1.000 atm. Use the van der Waals equation to estimate the pressure exerted by 1.000 mol of Cl2(_g_) in 22.41 L at 0.0°C (a = 6.49 L2-atm/mol2, b = 0.0562 , R = 0.08206 L-atm/mol-K). Read more

2018-11-13 11:46:55 | Physical Chemistry 251 C
The units of different Rate constants
The units of different Rate constants The _order_ of a rate law is the sum of the exponents of its concentration terms. Once the rate law of a reaction has been determined, that same law can be used to understand more fully the composition of the reaction mixture. More specifically, the reaction order is the exponent to which the concentration ... Read more

2018-10-30 11:36:41 | Physical Chemistry 251 C
First order Reaction
The RATE LAW or RATE EQUATION for a chemical reaction is an equation that links the reaction rate with the concentrations or pressures of the reactants and constant parameters (normally rate coefficients and partial reaction orders). A first order reaction depends on the concentration of only one reactant (a unimolecular reaction) IN 1ST ORDER REACTION:IN 1ST ORDER REACTION:IN 1ST ORDER ... Read more

2018-10-17 20:23:55 | Kinetic Theory 321 C
Total and Average Kinetic Energy
[1] A tank used for filling helium balloons has a volume of 0.300 m3 and contains 2.00 mol of helium gas at 20.0°C. Assume that the helium behaves like an ideal gas. (A) What is the total translational kinetic energy of the gas molecules? (B) What is the average kinetic energy per molecule? [2] What if the temperature is raised ... Read more