Digital Commons Network^™

Synthesis, Characterization And Genotoxicity Of Platinum(Ii)Complexes With Subtituted Benzimidazole Ligands, Özteki̇n Algül, Berri̇n Özçeli̇k, Ufuk Abbasoğlu, Fatma Gümüş

Turkish Journal of Chemistry

Five Pt(II) complexes with the ligands 2-ethyl-/ or-benzyl-/ or-phenoxymethyl- and 1-methyl-2-hydroxymethyl- and 1-methyl-2-phenyl- benzimidazoles were synthesized and characterized by elemental analysis, and IR and ^1H-NMR spectra and evaluated for their in vitro genotoxic activities by Rec-Assay test. Based on the data obtained in this study, the Pt(II) complexes tested might be taken into consideration as promising antitumor compounds.

Interpretation Of Sorption Kinetics For Mixtures Of Reactive Dyes On Wool, Eli̇f Şahi̇n

Turkish Journal of Chemistry

The equilibrium sorption isotherms of 3 reactive dyes (C. I. Reactive Yellow 84, C. I. Reactive Red 141, C. I. Reactive Blue 160) and their binary mixtures adsorbed on prewetted wool fiber were investigated. The kinetic studies were carried out at pH \le 7 and 80 °C in dye solutions containing 20 g/L NaCl. It was reported that binary mixtures of these reactive dyes have lower sorption values than the dyes alone, at the same dye concentration, pH and temperature. The isotherms obtained are Langmuir type. The rate parameters of adsorption kinetics decrease with increasing dye concentration.

Investigation Of Electron Transfer Reaction Between Diphenylbenzidine And Ascorbic Acid, Iftikhar Imam Naqvi, Abida Perveen

Turkish Journal of Chemistry

The kinetics of the reduction of diphenylbenzidine by ascorbic acid were investigated in the pH range 3.5 to 5.0. Diphenylbenzidine was prepared by the oxidation of diphenylamine with cerium(IV) sulfate tetra hydrate. The order of the reaction with respect to each of the reactants, i.e ascorbic acid (ASC), diphenylbenzidine (DPB) and H^+ ,was found to be first. The following rate law is recommended: Rate = {k_1 [C_{12}H_{10}N_2C_{12}H_{10}] + k_2K [C_{12}H_{10}N_2C_{12}H_{10}][H^+]}[C_6H_8O_6] where k_1 and k_2 have the values of 2.0 \times 10^4 dm^3mol^{-1} s^{-1} and 6.58 \times 10^3 dm^3.mol^{-1}.s^{-1} , respectively. K is the protonation constant of DPB, having a value …

A New Approach Towards (\Pm)-4-Ipomeanol And Its 2-Furyl Regioisomer, Jurgen Krauss, Franz Bracher, Doris Unterreitmeier

Turkish Journal of Chemistry

The cytotoxic furan derivative (\pm)-4-ipomeanol (1) and its regioisomer (8) were prepared in a new and efficient way starting from commercially available furan derivatives. In both cases the key step was a regioselective solvolysis of the terminal double bond with trifluoroacetic anhydride and boron trifluoride. The resulting compounds were tested in an agar diffusion assay against several bacteria and fungi, but did not show significant activity.

Synthesis Of 2-[2-(3,4,5-Trimethoxybenzoyloxy)Ethyl]Pyrrolidine Hydrochloride Controlled By Gc-Ms, ^1h And ^{13}C Nmr Analyses, Alicja Wodnicka, Malgorzata Dzieciol

Turkish Journal of Chemistry

The synthesis of 2-[2-(3,4,5-trimethoxybenzoyloxy)ethyl]pyrrolidine hydrochloride was performed using 2-(2-hydroxyethyl)pyrrolidine as a starting material. Before the O-acylation reaction with 3,4,5-trimethoxybenzoyl chloride, the amino group was protected using benzyl chlorocarbonate. The removal of the blocking group was carried out in modified conditions, avoiding the alcoholysis of the ester bond. The final product was separated from its structural isomer by precipitation as its hydrochloride salt. Some steps of the synthesis were controlled by GC-MS. The identification of the respective compounds was performed by mass spectra analyses and confirmed by ^1H NMR, ^{13}C NMR, IR and elemental analyses.

Spectrophotometric Study Of The Interaction Between Aza-15-Crown-5 And Some \Pi-Acceptors In Chloroform Solution, H. R. Pouretedal, A. Semnani, Mohammad Hossein Keshavarz, A. Firooz

Turkish Journal of Chemistry

A spectrophotometric study concerning the interaction between A15C5 as n-donor and TCNE, DDQ, TCNQ and bromanil as \pi -acceptor was been performed in chloroform at 25 °C. The results of TCNE indicate the formation of a 1:1 charge-transfer complex through a nonequilibrium reaction. In the case of DDQ, the formation of 1:2 (A15C5/DDQ) and 1:1 charge-transfer complexes through equilibrium and nonequilibrium reactions is confirmed. The formation constant of the equilibrium step was evaluated from the computer fitting of the absorbance-mole ratio data as logK_f = 5.14 \pm 0.09. The [A15C5^+ (DDQ)_2^- ] and [A15C5^+DDQ^- ] are suggested as the possible …

Heterogeneous Electron Transfer Rate Constants Of Viologen At A Platinum Disk Electrode, Naheed Kaukab Bhatti, M. Sadiq Subhani, Ather Yaseen Khan, Rumana Qureshi, Abdur Rahman

Turkish Journal of Chemistry

The transfer of electrons to the dications of viologens including methyl viologen, diquat, benzyl viologen and n-butyl viologen was studied at the surface of a platinum disk electrode. The rate constants for the processes were determined and the effects of solvent, temperature and working electrode studied. The studies showed that the rate constants increase with temperature and the effect of solvent on the heterogeneous electron transfer rate constant is related to the polarity, dielectric constant and viscosity of the solvent and on the electrode material. Theoretical rate constants were calculated by considering the effects of barrier crossing probability and nuclear-frequency …

Extraction-Spectrophotometric Determination Of Trace Amounts Of Barium And Strontium By 18-Crown-6 And Rose Bengal Using Partial Least Squares, Jahan B. Ghasemi, Alireza Nikrahi, Ali Niazi

Turkish Journal of Chemistry

Partial least squares modeling is a powerful multivariate statistical tool applied to extraction-spectrophotometric simultaneous determination of mixtures of barium and strontium. The method is based on the formation of the ternary complexes with 18C6 and rose bengal with barium and strontium. The 18C6-Ba-RB and 18C6-Sr-RB ternary complexes are quantitatively extracted into dichloromethane and the resolution of the mixtures is accomplished by partial least squares (PLS). In this study, the calibration model is based on absorption spectra in the 500-600 nm range for 25 different mixtures of barium and strontium. Calibration matrice's ranges were 0.05-5.50 and 0.03-4.50 \mu g mL^{-1} and …

Reactions Of Alkenes With Sodium Perborate And Sodium Chloride, Erdal Şenocak, Yavuz Taşkesengi̇l, Ferhan Tümer, Cavi̇t Kazaz

Turkish Journal of Chemistry

Sodium perborate oxidatively chlorinates a variety of alkenes with sodium chloride to form the corresponding chloro derivatives under mild conditions.

Construction And Characterization Of Indium Liquid Ion Selective Electrodes Based On Crown Ethers In A Pvc Matrix Membrane, Najwa I. Abdulla, Abdul-Muhsin Al-Haideri, Moen I. Al-Joboury, Nabil S. Nassory

Turkish Journal of Chemistry

Several indium ion selective electrodes were constructed based on 15-crown-5 (15C5), dicyclohexano-18-crown-6 (DCH18C6) and dibenzo-24-crown-8 (DB24C8) as sensors and di-octyl phenyl phosphonate (DOPP), di-butyl phthalate (DBPH), tri-butyl phosphate (DBP), tri-n-amyl phosphate (TAP) and bis (2-ethyl hexyl) phosphate (BEHP) as plasticizers in a PVC matrix membrane. Electrode parameters, pH effect and interferences were also studied. The indium electrode based on 15C5 using DOPP as a plasticizer gave the best response for low levels of In^{3+} ions. The linear range for this electrode ranged from 3.8 x 10^{-5} to 5.0 x 10^{-2} M (with correlation coefficient r = 0.9997), the slope was …

Characterization Of Tio_2 Synthesized In Alcohol By A Sol-Gel Process: The Effects Of Annealing Temperature And Acid Catalyst, Funda Sayilkan, Meltem Asi̇ltürk, Hi̇kmet Sayilkan, Yunus Önal, Murat Akarsu, Ertuğrul Arpaç

Turkish Journal of Chemistry

The effects of annealing temperature and hydrolysis catalyst on the crystalline form and crystallite size of TiO_2 prepared by a sol-gel process were investigated. Three types of TiO_2 were synthesized by hydrolysis of titanium(IV)-iso-propoxide with water in n-propanol without catalyst (Type-A) and with HCl as catalyst, where the H^+ /Ti^{4+} mol ratio was 0.54 for Type-B and 0.2 for Type-C. Hydrolysis products were thermally treated at 100, 200, 300, 400 and 500 °C for 1 h after drying at room temperature. Characterization of the particles was carried out using XRD, BET, TG/DTA and SEM analysis. The pore size distributions were …

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.

Cover And Contents

Turkish Journal of Agriculture and Forestry

No abstract provided.

The Problem Of Patent Underdevelopment, Michael B. Abramowicz

GW Law Faculty Publications & Other Works

Commentators have long recognized that much of the work of commercializing an invention occurs after a patent is received. They have not recognized, however, that by the time market conditions make commercialization potentially attractive, the remaining patent term might be sufficiently short that a patentee will not develop an invention or will not spend as much on development as if more patent term remained. The concern about patent underdevelopment provides a counterweight to patent prospect theory, which urges that patents be issued relatively early. By insisting on a substantial degree of achievement before patenting, the patent system reduces the risk …

Law And Accounting: Cases And Materials, Lawrence A. Cunningham

GW Law Faculty Publications & Other Works

Accounting textbooks for law or business schools invariably provide secondary narrative presentations of materials in the authors' own words. A better approach to learning this subject is to present thematically arranged original accounting pronouncements. The design this innovative book, helps readers appreciate how accounting is a tool that provides conceptual organization to economic exchange. The tool facilitates analyzing legal, business and public policy aspects of the transactions that accounting addresses. The original accounting standards, as well as SEC enforcement actions, presented in this book illuminate why transactions are pursued and related decisions made, economic aspects of transactions, and the conceptual …

Adapting To Climate Change In East Africa: A Strategic Approach, Victor A. Orindi, Laurel A. Murray

East Africa

This paper provides an overview of the likely impacts of climate change in three least developed countries in East Africa: Sudan, Tanzania, and Uganda. In the coming decades, climate change is likely to alter temperatures and distribution of rainfall, contribute to sea-level rise and increase the frequency and intensity of extreme weather events in East Africa. In fact, many widespread climatic changes have already been observed in the region. Climate change will have both a direct impact on development of climate-dependent activities (such as infrastructure and agriculture) and indirect consequences for social systems (such as issues of poverty, conflict, health …

Beneficial Reuse And Sustainability: The Fate Of Organic Compounds In The Land-Applied Waste, M. R. Overcash, Ronald C. Sims, J. L. Sims, K. C. Nieman

Biological Engineering Faculty Publications

Land application systems, also referred to as beneficial reuse systems, are engineered systems that have defined and permitted application areas based on site and waste characteristics to determine the land area size requirement. These terrestrial systems have orders of magnitude greater microbial capability and residence time to achieve decomposition and assimilation compared with aquatic systems. In this paper we focus on current information and information needs related to terrestrial fate pathways in land treatment systems. Attention is given to conventional organic chemicals as well as new estrogenic and pharmaceutical chemicals of commerce. Specific terrestrial fate pathways addressed include: decomposition, bound …

National Center For Engineering And Technology Education, Christine Hailey, Thomas Erekson, Kurt Becker, Maurice Thomas

Publications

The article reports that the overall impact of the National Center for Engineering and Technology Education (NCETE) is to strengthen the nation's capacity to deliver effective engineering and technology education in the K-12 schools. Further, it informs that the National Science Foundation established the Centers for Learning and Teaching (CLT) program to address needs in the science, technology, engineering, and mathematics (STEM) workforce. The CLT program has three goals, based upon stated national needs. First, CLT are expected to renew and diversify the cadre of national leaders in STEM education. The CLT includes partners with strengths in engineering and in …

Modeling Sediment Trapping In A Vegetative Filter Accounting For Converging Overland Flow, M. J. Helmers, D. E. Eisenhauer, Thomas G. Franti, Michael G. Dosskey

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Vegetative filters (VF) are used to remove sediment and other pollutants from overland flow. When modeling the hydrology of VF, it is often assumed that overland flow is planar, but our research indicates that it can be two-dimensional with converging and diverging pathways. Our hypothesis is that flow convergence will negatively influence the sediment trapping capability of VF. The objectives were to develop a two-dimensional modeling approach for estimating sediment trapping in VF and to investigate the impact of converging overland flow on sediment trapping by VF. In this study, the performance of a VF that has field-scale flow path …

Finite Element Modeling And Experimental Validation Of Cooling Rates Of Large Ready-To-Eat Meat Products In Small Meat-Processing Facilities, A. Amézquita, L. Wang, Curtis L. Weller

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A two−dimensional axisymmetric transient heat conduction model was developed to simulate air chilling of large ready−to−eat meat products of ellipsoidal shape. A finite element scheme, using 1,600 linear triangular elements with 861 nodes, was implemented in Matlab 6.5 to solve the model. The model considered a variable initial temperature distribution and combined convective, radiative, and evaporative boundary conditions. Predicted values agreed well with experimental data collected in actual processing conditions. Validation of model performance resulted in maximum deviations of 2.54°C and 0.29% for temperature and weight loss histories, respectively. The maximum temperature deviation (2.54°C) occurred at the surface; however, for …

An Analysis Of Accelerated Christian Education And College Preparedness Based On Act Scores, Lisa J.L. Kelley

Theses, Dissertations and Capstones

The current paper discusses Christian education in relation to college preparedness. The author focuses on Christian education and the use of Accelerated Christian Education, a prepackaged curriculum, specifically used in private fundamentalist Christian schools. Relevant research is reviewed regarding college preparedness and Christian education. The researcher obtained the ACT scores received by graduates of an ACE school over the past five years. These scores were analyzed using a t-test of comparative means (p<.05) to determine if there were a significant differences in ACT scores between students at the Accelerated Christian School and the students of a public high school in the same area with a graduate college application rate of 75-83%. Scores were analyzed and a significant difference was found between the public school graduatesí scores and the ACE graduatesí scores in all areas of the ACT (English, Math, Reading, and Composite Score), except the area of Science Reasoning. Overall, the ACT scores of the ACE graduates were consistently lower than those of the public school students.

Implementation Of Cooperative Groups And Single Gender Classrooms, Kara Haugen

Graduate Research Papers

The Dr. Walter Cunningham School for Excellence has three single-sex classrooms in place today. It has one all girls classroom at the second grade level, one all boys classroom at the second grade level, and one very unique all boys classroom at the first grade level. This classroom is unique because the teacher and the students will follow with each other all the way through fifth grade.

Since this is the first year of implementing single-sex classrooms there are many educators who need more clarification on this approach to education. In the following pages the researcher focuses on how the …

The Impact Of Math Teaching Strategies On Math Achievement, Patty Jenkins

Graduate Research Papers

The following study will highlight student achievement analysis of selected portions of the Iowa Test of Basic Skills of fourth grade students at Lincoln Elementary School. Teacher interviews about planning for teaching math, teaching strategies used, and outcomes are the second part of this research. A student survey about strategies teachers use and attitudes toward math is included along with the results of classroom action research. These data will be will be utilized to answer the question: Has the implementation of math teaching strategies had a positive impact on student math achievement at Lincoln Elementary School?

Could Distributed Curriculum Improve The Itbs Scores Of Non-Proficient Students?, Lesli Lancey-Wensman

Graduate Research Papers

Will the use of a distributed math curriculum improve the outcomes of students who consistently score between the 20th and 30th percentile on ITBS tests? That question and others are addressed in this paper. The purpose of this study was to determine what strategies were being used for math instruction, if those strategies were working for all students, and whether a distributed curriculum would improve the math outcomes of students with disabilities who were not working at their current grade level.

Mechanical Properties Of The Intervertebral Disc As An Estimator Of Postmortem Interval, Jennifer Noelle Jackson

Electronic Theses and Dissertations

Currently, forensic scientists are only able to determine time since death (or postmortem interval) up to the first 60 hours. This is based largely on insect activity. Herein, it is proposed to use the degradation of the intervertebral disc (IVD) after death to determine a relationship between the mechanical properties of cadaveric tissue and time since death in order to extend the 60-hour window. To that end, 1 fresh human spine and 6 pig spines were each separated into sections (6 human and 48 pig), with each section having one intact disc. The sections were buried, unearthed, and cleaned, leaving …

Diffraction Studies Of Deformation In Shape Memory Alloys And Selected Engineering Components, Chandrasen Rathod

Electronic Theses and Dissertations

Deformation phenomena in shape memory alloys involve stress-, temperature-induced phase transformations and crystallographic variant conversion or reorientation, equivalent to a twinning operation. In near equiatomic NiTi, Ti rich compositions can exist near room temperature as a monoclinic B19' martensitic phase, which when deformed undergoes twinning resulting in strains as large as 8%. Upon heating, the martensite transforms to a cubic B2 austenitic phase, thereby recovering the strain and exhibiting the shape memory effect. Ni rich compositions on the other hand can exist near room temperature in the austenitic phase and undergo a reversible martensitic transformation on application of stress. Associated …

Cover And Contents

Turkish Journal of Physics

No abstract provided.

Cover And Contents

Turkish Journal of Physics

No abstract provided.

Cover And Contents

Turkish Journal of Physics

No abstract provided.