Physical Sciences and Mathematics Commons^™

The Anthropogenic Influence On Cuejdi River Water Quality, Andreea Ghiurcă, Andreea Lămășanu, Florin C. Mihai

Florin C MIHAI

Water pollution is caused in rural areas, especially by uncontrolled waste deposits located in river bed and in urban areas is discharged, irregular, untreated sewage. The Cuejdiu River is a tributary of the Bitriţa River in the left side, with a total length of 24 km. Evaluation of water quality of the Cuejdiu River was achieved by processing the results obtained from tests analyzed for 30 samples, taken on March 17, 2012, between the mouth of the River Bestriţa and up to the exit of the village Cuiejdi. Analysis of water samples were performed in the laboratory of the Department …

Ultimate Detectability Of Volatile Organic Compounds: How Much Further Can We Reduce Their Ambient Air Sample Volumes For Analysis?, Ki-Hyun Kim

Ki-Hyun Kim

To understand the ultimately lowest detection range of volatile organic compounds (VOCs) in air, application of a high sensitivity analytical system was investigated by coupling thermal desorption (TD) technique with gas chromatography (GC) and time of flight (TOF) mass spectrometry (MS). The performance of the TD-GC-TOF MS system was evaluated using liquid standards of 19 target VOCs prepared in the range of 35 pg to 2.79 ng per μL. Studies were carried out using both total ion chromatograms (TIC) and extracted ion chromatograms (EIC) mode. EIC mode was used for calibration to reduce background and to improve signal to noise. …

Chemical Properties Of Forest Soils In The Catskills Region, Chris E. Johnson

Chris E Johnson

No abstract provided.

Recovery Of Sensitive Watersheds In The Northeastern United States From Chronic Acidification: The Role Of Soil Chemistry, Chris E. Johnson

Chris E Johnson

No abstract provided.

Room Temperature Syntheses Of Entirely Diverse Substituted Β-Fluorofurans, Li Yan, Kraig A. Wheeler, Roman Dembinski

Kraig A. Wheeler

Synthesis of highly substituted 3-fluorofurans is reported. The sequence began with preparation of tertbutyldimethylsilyl alk-1-en-3-yn-1-yl ethers from 1,4-disubstituted alk-3-yn-1-ones. Subsequent fluorination of alkenynyl silyl ethers with Selectfluor gave 2-fluoroalk-3-yn-1-ones in almost quantitative yield. Subsequent 5-endo-dig cyclizations using chlorotriphenylphosphine gold(I)/silver trifluoromethanesulfonate (5/5 mol%), N-bromo- or N-iodosuccinimide and gold(I) chloride/zinc bromide (5/20 mol%), all at room temperature, provided a facile method for the generation of substituted 3-fluoro-, 3-bromo-4-fluoro-, and 3-fluoro-4-iodofurans in good yields. Also, 2,2-difluoroalk-3-yn-1-ones were prepared by fluorination of alk-3-yn-1-ones under organocatalytic conditions. The structures of (Z)-tertbutyldimethylsilyl but-1-en-3-yn-1-yl ether, 3-bromo-4-fluorofuran, and 3-fluoro-4-(phenylethynyl)furan were confirmed by X-ray crystallography.

Nanocrystalline Amn2o4 (A = Co, Ni, Cu) Spinels For Remediation Of Volatile Organic Compounds—Synthesis, Characterization And Catalytic Performance, Ali Hosseini, Ali Niaei, Darioush Salari, Reza Nabavi

Seyed Reza nabavi

Nanocrystalline AMn2O4 (A = Co, Ni, Cu) manganite spinels were prepared by using the sol–gel auto combustion method under the same

synthesis conditions and their physico-chemical properties were studied by XRD, UV–vis DRS, SEM, BET and FTIR. Besides, the reducibility of

oxides was studied by temperature-programmed reduction (TPR). The relationship between the properties and activity of spinels in oxidation of 2-

propanol and toluene was investigated. Among all, nickel manganite exhibited the most promising activity, in which the completed conversion of 2-

propanol and toluene occurred at 250 and 350 8C, respectively. Higher activity of nickel manganite oxide was explained …

Butylated Hydroxytoluene Analogs: Synthesis And Evaluation Of Their Multipotent Antioxidant Activities, Azhar Ariffin

Azhar Ariffin

A computer-aided predictions of antioxidant activities were performed with the Prediction Activity Spectra of Substances (PASS) program. Antioxidant activity of compounds 1, 3, 4 and 5 were studied using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and lipid peroxidation assays to verify the predictions obtained by the PASS program. Compounds 3 and 5 showed more inhibition of DPPH stable free radical at 10(-4) M than the well-known standard antioxidant, butylated hydroxytoluene (BHT). Compound 5 exhibited promising in vitro inhibition of Fe2+-induced lipid peroxidation of the essential egg yolk as a lipid-rich medium (83.99%, IC50 16.07 +/- 3.51 mu M/mL) compared to alpha-tocopherol (alpha-TOH, 84.6%, IC50 …

Kinetic Analytical Method For Determination Of Uric Acid In Human Urine Using Analyte Pulse Perturbation Technique, Zeljko D. Cupic

Zeljko D Cupic

No abstract provided.

Determination Of Λ-Cyhalothrin In Palm And Palm Kernel Oils Using Tandem Solid-Phase Extraction Cartridges, Nor Kartini Binti Abu Bakar

Nor Kartini Binti Abu Bakar

This article outlines a new method based on low-temperature fat precipitation extraction with acetonitrile and graphitised carbon black/primary secondary amine (GCB/PSA) solid-phase extraction clean-up for the extraction of lambda-cyhalothrin residue in both crude palm oil (CPO) and crude palm kernel oil (CPKO). Determination of lambda-cyhalothrin was then carried out using gas chromatography (GC) equipped with an electron capture detector (ECD). Analyses for lambda-cyhalothrin in palm oil and palm kernel oil samples spiked with different levels of lambda-cyhalothrin (0.05, 0.08, 0.1, 0.5, and 1.0 mu g g(-1)) were performed. Mean recoveries for six replicates ranged from 82% to 98% for CPO …

Synthesis, Characterization And Nonlinear Optical Properties Of Silver/Pva Nanocomposites, Mahdi Shahmiri

mahdi shahmiri

Silver/polyvinyl alcohol (PVA) nanocomposites are prepared via quick precipitation method, using hydrazine as a reducing agent. Preparing of silver/PVA nanocomposites by this method is done for the first time. The samples are characterized by Uv-Visible spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM). Nonlinear optical properties are carried out by Z-scan technique using a blue CW laser beam operated at wavelength 405 nm. It is shown that the synthesized samples have negative nonlinear refractive index and the magnitude is in the order of 10􀀀8. The nonlinear refractive index increases as amount of reducing agent increases.

Pyrite. History, Chemistry, And Metallurgy, Fathi Habashi

Fathi Habashi

The Book covers the history of pyrite - - how it was a strategic mineral necessary for the production of elemental sulfur needed for making gunpowder for military purposes and for the production of SO2 needed for making sulfuric acid for the chemical industry. Now its presence is a nuisance in tailings ponds. The book also covers the processing of pyrite containing gold, its chemistry and technology, the processing of pyrite cinder for the production of a variety of metals, and its behaviour towards autotrophic microorganisms.

Facile Synthesis Of A Flexible Tethered Porphyrin Dimer That Preferentially Complexes Fullerene C70, Charles Michael Drain

Charles Michael Drain

A simple, high yield, two-step synthesis yields a porphyrin dimer linked by a flexible dithiol tether that preferentially binds fullerene C70 over C60 in toluene solution. The complex forms stable aggregates when cast on glass

Ogólnotechniczne Podstawy Biotechnologii Z Elementami Grafiki Inżynierskiej Ćw., Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.

Materiały Odstresowujące, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.

5x20 Matrix For Knowledge Management Lifecycle Based On The Five C’S Model And A Critical Review, Philadelphia University

Philadelphia University, Jordan

No abstract provided.

The Short Story In Jordan Its Origin And Development, Philadelphia University

Philadelphia University, Jordan

No abstract provided.

Oxidative Carbonylation Of 2-Propyn-1-Ol And 2-Methyl-3-Butyn-2-Ol In An Oscillatory Mode, Sergey N. Gorodsky

Sergey N. Gorodsky

No abstract provided.