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jih-1381
Equilibrium, Kinetic and Mechanistic Studies of Formation of Cis- mono (AA)bis (oxaJato) Chromate (III) C,omplex (where AA is · glycine, alanine and histidine)In Monderately Aqueous Acidic Solution
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Equilrium, kinetic  and mechanistic studies  for  thcoordination of

 

;

 

some amino acids  "'AA'1

 

glycine,  alanine, .a:ncl  histidine, to  Cr  (Ill)

 

center  of trans .[Cr(ox}2(B.2 0hr   {TJ'} cornplein monderarely  acidic

range ofpH=4.8-6-.7 ( p =Q.4M NaN03) are  reported.  The equili rium

c.onsta:nts   at  25°C   .were  found   logKequ.=4.95J ,5.206and5.128for glycine, alap.ine, md histidine, ligation. reactions  respectively..  The substitution reaction is kinetically  involve  rwo parallel  complex reactions, each  inch,tdes there  difierent e_onsecutive steps of different

·

 

species of Ct(III).  The  reactant,  Ti, branches  through  byrolysis  into, doubly  charged anion, conjugated    se of  trans[Cr(ox)22(H0)0Hr2

whlch  inleracts  with  (AAH)   to  from  outer-sphere  complex,   that  is followed  by interchange reaction  of one molecule H20 with one end of    AA-        ron   from                   an         active        intermediate         species   of              trans­ [Cr(Qx)2(AA)OHT3           which               cbanges       to        final           product ;                c.is­ [Cr(ox}1(AA)J?. While  the  remai ning  part  of reactant   interacts also

with zwitter i:on (AAH)  on  other  side  to form  another  outer-sphere

.complex  which  also  undergaes interchange  reaction of one  molecule

 

H10 wHh AA- ion to ive two· active  intennediates species, trans and cis-[Cr(ox)2(AA)H2 or, whlch later convert tp the same prod·uct .; cis­

fCr(ox)z(AA)]2-.      TI1e      interchange      rate      co.nstant    of     trans­ [Cr(ox)2(AA)OH]                                             formation  relatively   appears  much  larger  than (A H*=8.8kc 1/n1ol)         that                                 of    ds[Cr(.oxh  AA)H:z Ot                     formation

( l\ H*·=14.0Kca l/mol), wbile  the latter rate constant'is oeaily  (5-10)

time l(!I'ger than that oftrans-{Cr(ox)2(AA)H20t fennatlon

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Publication Date
Sat Aug 04 2012
Journal Name
University Of Thi-qar Journal
Prediction of Ultimate Soil Bearing Capacity for Shallow Strip Foundation on Sandy Soils by Using (ANN) Techniqu
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Bearing capacity of soil is an important factor in designing shallow foundations. It is directly related to foundation dimensions and consequently its performance. The calculations for obtaining the bearing capacity of a soil needs many varying parameters, for example soil type, depth of foundation, unit weight of soil, etc. which makes these calculation very variable–parameter dependent. This paper presents the results of comparison between the theoretical equation stated by Terzaghi and the Artificial Neural Networks (ANN) technique to estimate the ultimate bearing capacity of the strip shallow footing on sandy soils. The results show a very good agreement between the theoretical solution and the ANN technique. Results revealed that us

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Publication Date
Sat Dec 03 2016
Journal Name
Journal Of Genetic And Environmental Resources Conservation
Examination the efficiency of NDVI index by comparing with STVI-4 index to recognize the vegetation cover
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Publication Date
Fri Mar 20 2020
Journal Name
Journal Of Xi'an University Of Architecture & Technology
Academic Laboratory Skills For Chemistry Students at the College of Education For Pure Sciences -Ibn Al Haitham
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The current research aims to find out the extent to which students of the Faculty of Education for Pure Sciences\/Ibn al-Haitham have owned laboratory academic skills, the researcher adopted a descriptive research approach to conform to the goal of the research, the research sample the consisted of 140 students from the Department of Chemistry Phase II, The research tool, which consisted of a measure of laboratory academic skills, which consisted of seven skills and consisted of 28 paragraphs (four paragraphs per field), was prepared and the pent-up scale was chosen because the selected sample were university students, and the results showed the ownership of students' skills of laboratory academic skills other than skill The use of the libr

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Publication Date
Wed Jul 11 2018
Journal Name
دراسات تربوية
Understanding the nature of the scientific endeavor among chemistry teachers according to the Educational Reform Project 2061
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Publication Date
Thu May 04 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Influence Annealing on the Physical Properties of Silver Selenide Thin Film at Different Temperatures by Thermal Evaporation
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This survey investigates the thermal evaporation of Ag2Se on glass substrates at various thermal annealing temperatures (300, 348, 398, and 448) °K. To ascertain the effect of annealing temperature on the structural, surface morphology, and optical properties of Ag2Se films, investigations and research were carried out. The crystal structure of the film was described by Xray diffraction and other methods.The physical structure and characteristics of the Ag2Se thin films were examined using X-ray and atomic force microscopy (AFM) based techniques. The Ag2Se films surface morphology was examined by AFM techniques; the investigation gave average diameter, surface roughness, and grain size mutation values with increasing annealing temperature

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Publication Date
Wed Apr 01 2009
Journal Name
International Journal Of Applied Environmental Sciences
An expert System for Predicting the Effects of Noise Pollution on Grass Trimming Task Using Fuzzy Modeling
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Grass trimming operation is widely done in Malaysia for the purpose of maintaining highways. Large number of operators engaged in this work encounters high level of noise generated by back pack type grass trimmer used for this purpose. High level of noise exposure gives different kinds of ill effect on human operators. Exact nature of deteriorated work performance is not known. For predicting the work efficiency deterioration, fuzzy tool has been used in present research. It has been established that a fuzzy computing system will help in identification and analysis of fuzzy models fuzzy system offers a convenient way of representing the relationships between the inputs and outputs of a system in the form of IF-THEN rules. The paper presents

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Publication Date
Wed Mar 08 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
PVC Polymeric Membranes Coated Graphite Electrodes Based on Molecularly Imprinted Polymers for the Selective Determination of Glibenclamide
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Graphite coated electrodes (GCE) based on molecularly imprinted polymers were fabricated for the selective potentiometric determination of Glibenclamide (Glb). The molecularly imprinted (MIP) and nonimprinted (NIP) polymers were synthesized by radical bulk polymerization using (Glb.) as a template, acrylic acid (AA) and acrylamide (AAm) as monomers, ethylene glycol dimethacrylate (EGDMA) as a cross-linker and benzoyl peroxide (BPO) as an initiator. The imprinted membranes and the non-imprinted membranes were prepared using dioctyl phthalate (DOP) and Dibutylphthalate (DBP) as plasticizers in PVC matrix. The membranes were coated on graphite electrodes. The MIP electrodes using (AA) and (AAm) showed a near nernstian response with slopes o

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Publication Date
Tue Mar 18 2025
Journal Name
Journal Of Physical Education
Using of special exercises to mtaulp speed to pass the test (150×20) for women football referees
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Publication Date
Fri Jul 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Comparison some of methods wavelet estimation for non parametric regression function with missing response variable at random
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Abstract

 The problem of missing data represents a major obstacle before researchers in the process of data analysis in different fields since , this problem is a recurrent one in all fields of study including social , medical , astronomical and clinical experiments .

The presence of such a problem within the data to be studied may influence negatively on the analysis and it may lead to misleading conclusions , together with the fact that these conclusions that result from a great bias caused by that problem in spite of the efficiency of wavelet methods but they are also affected by the missing of data , in addition to the impact of the problem of miss of accuracy estimation

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Publication Date
Sat Dec 02 2023
Journal Name
Journal Of Engineering
Performance Assessment of Pile Models Chemically Grouted by Low-Pressure Injection Laboratory Device for Improving Loose Sand
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The complexity and partially defined nature of jet grouting make it hard to predict the performance of grouted piles. So the trials of cement injection at a location with similar soil properties as the erecting site are necessary to assess the performance of the grouted piles. Nevertheless, instead of executing trial-injected piles at the pilot site, which wastes money, time, and effort, the laboratory cement injection devices are essential alternatives for evaluating soil injection ability. This study assesses the performance of a low-pressure laboratory grouting device by improving loose sandy soil injected using binders formed of Silica Fume (SF) as a chemical admixture (10% of Ordinary Portland Cement OPC mass) to di

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