Properties of Polar Covalent Bonds
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Application of Aluminium Oxide Nanoparticles to Enhance Rheological and Filtration Properties of Water Based Muds at HPHT Condit
Application of Aluminium Oxide Nanoparticles to Enhance Rheological and Filtration Properties of Water Based Muds at HPHT Conditions Sean Robert Smith1, Roozbeh Rafati*1, Amin Sharifi Haddad1, Ashleigh Cooper2, Hossein Hamidi1 1School of Engineering, University of Aberdeen, Aberdeen, United Kingdom, AB24 3UE 2Baroid Drilling Fluid Laboratory, Halliburton, Dyce, Aberdeen, United Kingdom, AB21 0GN Abstract Drilling fluid is of one of the most important elements of any drilling operation, and through ever advancing technologies for deep water and extended reach drillings, enhancement of drilling fluids properties for such harsh conditions need to be investigated. Currently oil based fluids are used in these types of advanced drilling operations, as their performance at high pressure and high temperature conditions, and deviated wells are superior compared to water based fluids. However, the high costs associated with using them, and environmental concerns of such oil base fluids are drawbacks of them at the moment. In this study, we tried to find a solution for such issues through investigation on the potential application of a new nano-enhanced water base fluid for advanced drilling operations. We analysed the performance of water base drilling fluids that were formulated with two type of nanomaterials (aluminium oxide and silica) at both high and low pressure and temperature conditions (high: up to 120 oC and 500 psi, low: 23 oC and 14.7 psi). The results were compared with a base case drilling fluid with no nanomaterial, and they showed that there is an optimum concentration for aluminium oxide nanoparticles that can be used to improve the rheological and filtration properties of drilling fluids. -
Reference 2341
Waste Isolation Pilot Plant Compliance Certification Application Reference 2341, EPA (U. S. Environmental Protection Agency). 1986. Test Methods for Evaluating Solid Waste, PhysicallChemical Methods, SW-846, 3rd ed., Office of Solid Waste and Emergency Response, Washington, D.C. Volume IB, Part A. Submitted in accordance with 40 CFR 5 194.13, Submission of Reference Materials. United Stetes Office of Solid Weste November 1988 Environmentel Protection - end Emergency Response SWW Aeenc~ Weshington, DC 20460 Third Edition Test Methods for Evaluating Solid Waste Volume IB: Laboratory Manual Physical/Chemical Methods CPMTA) VOLUHE ONE, SECTION B S'A!-BOt; Test Meti?r!as ioi Evaiuntin!~ Solia ii~ss?~ ~'i~ysicalICl~en~icalUictliocis Laboratory Manual ?j~lui~lt.I5 - ' m ?or n). by th OmmimtrJaat of I)OCmmaata. U.I. OOIQUI.t Ola WaILIm#to& D.C. ¶O&W 1YI DISCLAIMER Mention of trade names or commercial products does not constitute endorsement or recommendat ion for use by the U. S. Environmental Protection Agency. SW-846 methods are designed to be used with equipment from any manufacturer that results in suitable method performance (as assessed by accuracy, precision, detection 1 imits and matrix compati bi1 ity) . In several SW-846 methods, equipment specifications and settings are given for tfie specific instrument used during method development, or subsequently approved for use in the method. These references are made to provide the best possible guidance to laboratories using this manual. Equipment not specified in the method may be used as long as the 1 aboratory achieves equivalent or superior method performance. If a1 ternate equipment is used, the 1 aboratory must foll ow the manufacturer's instructions for their particular instrument. -
Physical-Chemical Properties of Complex Natural Fluids
Physical-chemical properties of complex natural fluids Vorgelegt von Diplom-Geochemiker Diplom-Mathematiker Sergey Churakov aus Moskau an der Fakultät VI - Bauingenieurwesen und Angewandte Geowissenschaften - der Technischen Universität Berlin zur Erlangung des akademischen Grades Doktor der Naturwissenschaften - Dr. rer. nat. - genehmigte Dissertation Berichter: Prof. Dr. G. Franz Berichter: Prof. Dr. T. M. Seward Berichter: PD. Dr. M. Gottschalk Tag der wissenschaftlichen Aussprache: 27. August 2001 Berlin 2001 D83 Abstract The dissertation is focused on the processes of transport and precipitation of metals in high temperature fumarole gases (a); thermodynamic properties of metamorphic fluids at high pressures (b); and the extent of hydrogen-bonding in supercritical water over wide range of densities and temperatures (c). (a) At about 10 Mpa, degassing of magmas is accompanied by formation of neary ‘dry’ salt melts as a second fluid phase, very strong fractionation of hydrolysis products between vapour and melts, as well as subvalence state of metals during transport processes. Based on chemical analyses of gases and condensates from high-temperature fumaroles of the Kudryavy volcano (i Iturup, Kuril Arc, Russia), a thermodynamic simulation of transport and deposition of ore- and rock-forming elements in high-temperature volcanic gases within the temperature range of 373-1373 K at 1 bar pressure have been performed. The results of the numerical simulations are consistent with field observations. Alkali and alkali earth metals, Ga, In, Tl, Fe, Co, Ni, Cu, and Zn are mainly transported as chlorides in the gas phase. Sulfide and chloride forms are characteristic of Ge, Sn, Pb, and Bi at intermediate and low temperatures. -
Impact of Solute Molecular Properties on the Organization of Nearby Water: a Cellular Automata Model
Digest Journal of Nanomaterials and Biostructures Vol. 7, No. 2, April - June 2012, p. 469 - 475 IMPACT OF SOLUTE MOLECULAR PROPERTIES ON THE ORGANIZATION OF NEARBY WATER: A CELLULAR AUTOMATA MODEL C. MIHAIa, A. VELEAb,e, N. ROMANc, L. TUGULEAa, N. I. MOLDOVANd** aDepartment of Electricity, Solid State and Biophysics, Faculty of Physics, University of Bucharest, Romania bNational Institute of Materials Physics, Bucharest - Magurele, Romania cDepartment of Computer Science, The Ohio State University - Lima, Ohio, USA dDepartment of Internal Medicine, Davis Heart and Lung Research Institute, The Ohio State University - Columbus, Ohio, USA e"Horia Hulubei” Foundation, Bucharest-Magurele, Romania The goal of this study was the creation of a model to understand how solute properties influence the structure of nearby water. To this end, we used a two-dimensional cellular automaton model of aqueous solutions. The probabilities of translocation of water and solute molecules to occupy nearby sites, and their momentary distributions (including that of vacancies), are considered indicative of solute molecular mechanics and hydrophatic character, and are reflected in water molecules packing, i.e. ‘organization’. We found that in the presence of hydrophilic solutes the fraction of water molecules with fewer neighbors was dominant, and inverse-proportionally dependent on their relative concentration. Hydrophobic molecules induced water organization, but this effect was countered by their own flexibility. These results show the emergence of cooperative effects in the manner the molecular milieu affects local organization of water, and suggests a mechanism through which molecular mechanics and crowding add a defining contribution to the way the solute impacts on nearby water. -
Synthesis and Investigation of the Properties of Water Soluble Quantum Dots for Bioapplications
Synthesis and Investigation of the Properties of Water Soluble Quantum Dots for Bioapplications A Thesis by Fatemeh Mir Najafi Zadeh Submitted in Partial Fulfilment of the Recruitment for the Degree of Doctor of Philosophy in Chemistry Supervisor: A/Prof. John A.Stride Co-supervisor: A/Prof. Marcus Cole School of Chemistry Faculty of Science August 2014 The University of New South Wales Thesis/ Dissertation Sheet Surname or family name: Mir Najafi Zadeh First name: Fatemeh Other name/s: Abbreviation for degree as given in the University calendar: PhD School: Chemistry Faculty: Science Title: Synthesis and Investigation of the Properties of Water Soluble Quantum Dots for Bioapplications Abstract Semiconductor nanocrystals or quantum dots (QDs) have received a great deal of attention over the last decade due to their unique optical and physical properties, classifying them as potential tools for biological and medical applications. However, there are some serious restrictions to the bioapplications of QDs such as water solubility, toxicity and photostability in biological environments for both in-vivo and in-vitro studies. In this thesis, studies have focused on the preparation of highly luminescent, water soluble and photostable QDs of low toxicity that can then be potentially used in a biological context. First, CdSe nanoparticles were synthesized in an aqueous route in order to investigate the parameters affecting formation of nanoparticles. Then, water soluble CdSe(S) and ZnSe(S) QDs were synthesized. These CdSe(S) QDs were also coated with ZnO and Fe2O3 to produce CdSe(S)/ZnO and CdSe(S)/Fe2O3 core/shell QDs. The cytotoxicities of as-prepared CdSe(S), ZnSe (S) and CdSe(S)/ZnO QDs were studied in the presence of two cell lines: HCT-116 cell line as cancer cells and WS1 cell line as normal cells. -
The Water Molecule
Seawater Chemistry: Key Ideas Water is a polar molecule with the remarkable ability to dissolve more substances than any other natural solvent. Salinity is the measure of dissolved inorganic solids in water. The most abundant ions dissolved in seawater are chloride, sodium, sulfate, and magnesium. The ocean is in steady state (approx. equilibrium). Water density is greatly affected by temperature and salinity Light and sound travel differently in water than they do in air. Oxygen and carbon dioxide are the most important dissolved gases. 1 The Water Molecule Water is a polar molecule with a positive and a negative side. 2 1 Water Molecule Asymmetry of a water molecule and distribution of electrons result in a dipole structure with the oxygen end of the molecule negatively charged and the hydrogen end of the molecule positively charged. 3 The Water Molecule Dipole structure of water molecule produces an electrostatic bond (hydrogen bond) between water molecules. Hydrogen bonds form when the positive end of one water molecule bonds to the negative end of another water molecule. 4 2 Figure 4.1 5 The Dissolving Power of Water As solid sodium chloride dissolves, the positive and negative ions are attracted to the positive and negative ends of the polar water molecules. 6 3 Formation of Hydrated Ions Water dissolves salts by surrounding the atoms in the salt crystal and neutralizing the ionic bond holding the atoms together. 7 Important Property of Water: Heat Capacity Amount of heat to raise T of 1 g by 1oC Water has high heat capacity - 1 calorie Rocks and minerals have low HC ~ 0.2 cal. -
Thermophysical Properties of Materials for Water Cooled Reactors
XA9744411 IAEA-TECDOC-949 Thermophysical properties of materials for water cooled reactors June 1997 ¥DL 2 8 fe 2 Q The IAEA does not normally maintain stocks of reports in this series. However, microfiche copies of these reports can be obtained from IN IS Clearinghouse International Atomic Energy Agency Wagramerstrasse 5 P.O. Box 100 A-1400 Vienna, Austria Orders should be accompanied by prepayment of Austrian Schillings 100,- in the form of a cheque or in the form of IAEA microfiche service coupons which may be ordered separately from the IN IS Clearinghouse. IAEA-TECDOC-949 Thermophysical properties of materials for water cooled reactors WJ INTERNATIONAL ATOMIC ENERGY AGENCY /A\ June 1997 The originating Section of this publication in the IAEA was: Nuclear Power Technology Development Section International Atomic Energy Agency Wagramerstrasse 5 P.O. Box 100 A-1400 Vienna, Austria THERMOPHYSICAL PROPERTIES OF MATERIALS FOR WATER COOLED REACTORS IAEA, VIENNA, 1997 IAEA-TECDOC-949 ISSN 1011-4289 ©IAEA, 1997 Printed by the IAEA in Austria June 1997 FOREWORD The IAEA Co-ordinated Research Programme (CRP) to establish a thermophysical properties data base for light and heavy water reactor materials was organized within the framework of the IAEA's International Working Group on Advanced Technologies for Water Cooled Reactors. The work within the CRP started in 1990. The objective of the CRP was to collect and systematize a thenmophysical properties data base for light and heavy water reactor materials under normal operating, transient and accident conditions. The important thermophysical properties include thermal conductivity, thermal diffusivity, specific heat capacity, enthalpy, thermal expansion and others. -
Micellar Assembly and Disassembly of Organoselenium Block Copolymers Through Alkylation and Dealkylation Processes
polymers Communication Micellar Assembly and Disassembly of Organoselenium Block Copolymers through Alkylation and Dealkylation Processes Taejun Eom and Anzar Khan * Department of Chemical and Biological Engineering, Korea University, 145 Anam-Ro, Seongbuk-Gu, Seoul 02841, Korea; [email protected] * Correspondence: [email protected]; Tel.: +82-2-3290-4859 Abstract: The aim of this work is to demonstrate that the alkylation and dealkylation of selenium atoms is an effective tool in controlling polymer amphiphilicity and, hence, its assembly and dis- assembly process in water. To establish this concept, poly(ethylene glycol)-block-poly(glycidyl methacrylate) was prepared. A post-synthesis modification with phenyl selenolate through a base- catalyzed selenium-epoxy ‘click’ reaction then gave rise to the side-chain selenium-containing block copolymer with an amphiphilic character. This polymer assembled into micellar structures in water. However, silver tetrafluoroborate-promoted alkylation of the selenium atoms resulted in the forma- tion of hydrophilic selenonium tetrafluoroborate salts. This enhancement in the chemical polarity of the second polymer block removed the amphiphilic character from the polymer chain and led to the disassembly of the micellar structures. This process could be reversed by restoring the original amphiphilic polymer character through the dealkylation of the cations. Keywords: organoselenium polymers; selenium-epoxy ‘click’ reaction; alkylation/dealkylation; Citation: Eom, T.; Khan, A. Micellar polymer assembly; micellar nanostructures; micellar disassembly Assembly and Disassembly of Organoselenium Block Copolymers through Alkylation and Dealkylation Processes. Polymers 2021, 13, 2456. 1. Introduction https://doi.org/10.3390/ polym13152456 In nature, reversible methylation and demethylation processes play a critical role in determining protein structure and function [1]. -
TLC Conditions.Pdf
DETERMINATION OF OPTIMUM CONDITIONS FOR SEPARATION BY TLC PURPOSE Experimentally determine the optimum thin layer chromatography conditions for separating a mixture of three structurally related aromatic compounds. MATERIALS • pre-cut TLC plates containing UV indicator • two capped bottles or covered beakers to hold TLC plates • capillary pipets for spotting TLC plates • solution mixture of the three test substances combined • solutions of each pure test substance • variety of chromatography solvents • ultraviolet light source THEORY Thin Layer Chromatography (TLC) utilizes a glass plate or plastic sheet coated with an absorbent such as silica gel. This serves as the stationary phase. After a mixture is "spotted" onto a position near the bottom this plate, the plate is placed in a shallow pool of solvent in a beaker or jar. This solvent (the mobile phase) travels up the plate, carrying the mixture components with it. However, the components of the spotted mixture travel at different rates based on factors such as chemical polarity and size. Chemists seek the best solvent conditions that will achieve optimum separation of the components from the initial mixture. Understanding the concept that "like-dissolves-like", compounds that are more polar will tend to dissolve and stay soluble in polar solvents. Therefore, use of a polar solvent would result in rapid movement of a polar compound up a TLC plate. Lesser polarity components in the mixture would not move up the plate as rapidly. In this lab, you should consider the structural differences between the three compounds you are to separate. You must then consider the relative polarities that have been established for common laboratory solvents. -
Thickness and Structure of Adsorbed Water Layer and Effects on Adhesion and Friction at Nanoasperity Contact
colloids and interfaces Review Thickness and Structure of Adsorbed Water Layer and Effects on Adhesion and Friction at Nanoasperity Contact Chen Xiao 1, Pengfei Shi 1, Wenmeng Yan 1, Lei Chen 1,*, Linmao Qian 1 and Seong H. Kim 1,2 1 Tribology Research Institute, Key Laboratory of Advanced Technology of Materials, Ministry of Education, Southwest Jiaotong University, Chengdu 610031, China 2 Department of Chemical Engineering and Materials Research Institute, The Pennsylvania State University, University Park, PA 16802, USA * Correspondence: [email protected]; Tel.: +86-159-8213-9010 Received: 30 June 2019; Accepted: 2 August 2019; Published: 6 August 2019 Abstract: Most inorganic material surfaces exposed to ambient air can adsorb water, and hydrogen bonding interactions among adsorbed water molecules vary depending on, not only intrinsic properties of material surfaces, but also extrinsic working conditions. When dimensions of solid objects shrink to micro- and nano-scales, the ratio of surface area to volume increases greatly and the contribution of water condensation on interfacial forces, such as adhesion (Fa) and friction (Ft), becomes significant. This paper reviews the structural evolution of the adsorbed water layer on solid surfaces and its effect on Fa and Ft at nanoasperity contact for sphere-on-flat geometry. The details of the underlying mechanisms governing water adsorption behaviors vary depending on the atomic structure of the substrate, surface hydrophilicity and atmospheric conditions. The solid surfaces reviewed in this paper include metal/metallic oxides, silicon/silicon oxides, fluorides, and two-dimensional materials. The mechanism by which water condensation influences Fa is discussed based on the competition among capillary force, van der Waals force and the rupture force of solid-like water bridge. -
Solubility Handbook Collected from Wikipedia by Khaled Gharib ([email protected])
Solubility handbook Collected from wikipedia by Khaled Gharib ([email protected]) PDF generated using the open source mwlib toolkit. See http://code.pediapress.com/ for more information. PDF generated at: Sat, 31 Mar 2012 09:49:23 UTC Contents Articles What is solubility 1 Solubility 1 Solubility chart 8 Solubility chart 8 Solubility table 10 Solubility table 10 References Article Sources and Contributors 39 Image Sources, Licenses and Contributors 40 Article Licenses License 41 1 What is solubility Solubility Solubility is the property of a solid, liquid, or gaseous chemical substance called solute to dissolve in a solid, liquid, or gaseous solvent to form a homogeneous solution of the solute in the solvent. The solubility of a substance fundamentally depends on the used solvent as well as on temperature and pressure. The extent of the solubility of a substance in a specific solvent is measured as the saturation concentration where adding more solute does not increase the concentration of the solution. Most often, the solvent is a liquid, which can be a pure substance or a mixture.[1] One may also speak of solid solution, but rarely of solution in a gas (see vapor-liquid equilibrium instead). The extent of solubility ranges widely, from infinitely soluble (fully miscible[2]) such as ethanol in water, to poorly soluble, such as silver chloride in water. The term insoluble is often applied to poorly or very poorly soluble compounds. Under certain conditions, the equilibrium solubility can be exceeded to give a so-called supersaturated solution, which is metastable.[3] Solubility is not to be confused with the ability to dissolve or liquefy a substance, because the solution might occur not only because of dissolution but also because of a chemical reaction. -
Degradation, Metabolism and Relaxation Properties of Iron Oxide Particles for Magnetic Resonance Imaging
Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine 1362 Degradation, Metabolism and Relaxation Properties of Iron Oxide Particles for Magnetic Resonance Imaging BY KAREN BRILEY SAEBO ACTA UNIVERSITATIS UPSALIENSIS UPPSALA 2004 Uppsala University Department of Oncology, Radiology and Clinical Immunology Section of Radiology Akademiska sjukhuset SE-751 85 Uppsala, Sweden Dissertation in Radiology to be publicly examined in Gröwallsalen, Akademiska sjukhuset, Uppsala, Th ursday, June 3, 2004, at 13:15, for the degree of Doctor of Philosophy (Faculty of Medicine). Th e examination will be conducted in English. Abstract Briley Saebo, K. Degradation, Metabolism and Relaxation Properties of Iron Oxide Particles for Mag- netic Resonance Imaging. Acta Universitatis Upsaliensis. Comprehensive summaries of Uppsala Disser- tations from the Faculty of Medicine 1362. 92 pp. Uppsala. ISBN 91-554-5998-6. Whereas the eff ect of size and coating material on the pharmacokinetics and biodistribution of iron oxide based contrast agents are well documented, the eff ect of these parameters on liver metabolism has never been investigated. Th e primary purpose of this work was to evaluate the eff ect of iron oxide particle size and coating on the rate of liver clearance and particle degradation using a rat model. Th e magnetic and relaxation properties of fi ve diff erent iron oxide contrast agents were determined prior to the onset of the animal studies. Th e R2* values and the T1-enhancing effi cacy of the agents were also evaluated in blood using phantom models. Th e results of these studies indicated that the effi - cacy of these agents was matrix and frequency dependent.