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For elements

Johanssen S A E and Campbeii J L 1988 FIXE A Novel Technique for Elemental Analysis (Chichester Wiiey) Covers PiXE in detaii and is a good reference for graduate students and researchers. [Pg.1851]

The strong point of AES is that it provides a quick measurement of elements in the surface region of conducting samples. For elements having Auger electrons with energies hr the range of 100-300 eV where the mean free path of the electrons is close to its minimum, AES is considerably more surface sensitive than XPS. [Pg.1859]

Element 103, lawrencium, completes the actinides. Following this series, the transition elements should continue with the filling of the 6d orbitals. There is evidence for an element 104 (eka-hafnium) it is believed to form a chloride MCl4, similar to that of hafnium. Less positive evidence exists for elements 105 and 106 attempts (so far unsuccessful) have been made to synthesise element 114 (eka-lead). because on theoretical grounds the nucleus of this elemeni may be stable to decay by spontaneous fusion (as indeed is lead). Super-... [Pg.444]

Parameters for elements (basis liinctions in ah miiw methods usually derived from experimental data and empirical parameters in semi-empirical methods nsually obtained from empirical data or ah initu> calcii la lion s) are in depen den t of th e ch em -leal environment, [n contrast, parameters used in molecular mechanics methods often depend on the chem ical en viron-ment. [Pg.33]

Most nitrocompounds react vigorously with metallic sodium during the tests for elements present (p. 321). [Pg.384]

In conjunction with the use of isoparametric elements it is necessary to express the derivatives of nodal functions in terms of local coordinates. This is a straightforward procedure for elements with C continuity and can be described as follows Using the chain rule for differentiation of functions of multiple variables, the derivative of a function in terms of local variables ij) can be expressed as... [Pg.37]

With respect to the selected elemental and global orders of node numbering the elemental stiffness equations for elements ei, eu and em in Figure 6.4 are expressed as... [Pg.197]

If no water is present in the mixture, use it directly in the tests for elements. [Pg.1093]

New data, reportedly issued by Soviet scientists, have reduced the half-life of the isotope they worked with from 0.3 to 0.15 s. The Dubna scientists suggest the name kurchatauium and symbol Ku for element 104, in honor of Igor Vasilevich Kurchatov (1903-1960), former Head of Soviet Nuclear Research. [Pg.158]

Other experiments were made to aid in confirmation of the discovery. Neither the Dubna team nor the Berkeley-Eivermore Group has proposed a name as of yet for element 106 (unnilhexium). [Pg.162]

Lewis structures in which second row elements own or share more than eight valence electrons are especially unstable and make no contribution to the true structure (The octet rule may be ex ceeded for elements beyond the second row)... [Pg.26]

Gases and vapors of volatile liquids can be introduced directly into a plasma flame for elemental analysis or for isotope ratio measurements. Some elements can be examined by first converting them chemically into volatile forms, as with the formation of hydrides of arsenic and tellurium. It is important that not too much analyte pass into the flame, as the extra material introduced into the plasma can cause it to become unstable or even to go out altogether, thereby compromising accuracy or continuity of measurement. [Pg.102]

Calibration of an arc or spark source is linear over three orders of magnitude, and detection limits are good, often within the region of a few micrograms per gram for elements such as vanadium, aluminum, silicon, and phosphorus. Furthermore, the nature of the matrix material composing the bulk of the sample appears to have little effect on the accuracy of measurement. [Pg.114]

For elements with lower nuclear charges than tin, the aj-a2 splitting is smaller because of the reduced spin-orbit coupling. For example for calcium, with Z = 20, the splitting is only about 3 eV and usually unresolved. [Pg.326]

Other techniques in which incident photons excite the surface to produce detected electrons are also Hsted in Table 1. X-ray photoelectron Spectroscopy (xps), which is also known as electron spectroscopy for chemical analysis (esca), is based on the use of x-rays which stimulate atomic core level electron ejection for elemental composition information. Ultraviolet photoelectron spectroscopy (ups) is similar but uses ultraviolet photons instead of x-rays to probe atomic valence level electrons. Photons are used to stimulate desorption of ions in photon stimulated ion angular distribution (psd). Inverse photoemission (ip) occurs when electrons incident on a surface result in photon emission which is then detected. [Pg.269]

The lines of primary interest ia an xps spectmm ate those reflecting photoelectrons from cote electron energy levels of the surface atoms. These ate labeled ia Figure 8 for the Ag 3, 3p, and 3t7 electrons. The sensitivity of xps toward certain elements, and hence the surface sensitivity attainable for these elements, is dependent upon intrinsic properties of the photoelectron lines observed. The parameter governing the relative iatensities of these cote level peaks is the photoionization cross-section, (. This parameter describes the relative efficiency of the photoionization process for each cote electron as a function of element atomic number. Obviously, the photoionization efficiency is not the same for electrons from the same cote level of all elements. This difference results ia variable surface sensitivity for elements even though the same cote level electrons may be monitored. [Pg.275]

As indicated in Figure 4, the early transactinide elements find their place back in the main body of the Periodic Table. The discoverers of the currendy known transactinide elements, suggested names and symbols, and dates of discovery are Hsted in Table 10 (19). Because there are competing claims for the discovery of these elements, the two groups of discoverers in each case have suggested names for elements 104 and 105. In the case of elements 106—109, names for the elements have not been suggested in order to avoid another dupHcation. [Pg.225]

Study of the chemical properties of element 104 has confirmed that it is indeed homologous to hafnium as demanded by its position in the Periodic Table (20). Chemical studies have been made for element 105, showing some similarity to tantalum (25) no chemical studies have been made for elements 106—109. Such studies are very difficult because the longest-Hved isotope of 104 ( 104) has a half-Hfe of only about 1 min, of 105 ( 105) a half-Hfe of about 40 s, of 106 ( 106) a half-Hfe of about 1 s, and of elements 107—109 half-Hves in the range of milliseconds. [Pg.225]

Elemental chemical analysis provides information regarding the formulation and coloring oxides of glazes and glasses. Energy-dispersive x-ray fluorescence spectrometry is very convenient. However, using this technique the analysis for elements of low atomic numbers is quite difficult, even when vacuum or helium paths are used. The electron-beam microprobe has proven to be an extremely useful tool for this purpose (106). Emission spectroscopy and activation analysis have also been appHed successfully in these studies (101). [Pg.422]

In view of the chromophoric character of the elemental iodine itself, many colorimetric methods have been proposed for the deterrnination of inorganic iodine (88—92). These methods use the visible portion of the spectmm in reading iodine concentrations. In the visible range the extinction coefficient for iodine is not high enough to be used for minute quantities of iodine in water and other solvents (93). Higher sensitivities have been reported for elemental iodine in potassium iodide solutions in the ultraviolet (93,94). [Pg.364]

By agreement between the purchaser and the suppHer, analyses may also be requited and limits estabUshed for elements or compounds not specified. This grade is intended for chemical appHcations requiting low silver and bismuth contents. [Pg.52]

The two most useful supplementary techniques for the light microscope are EDS and FTIR microscopy. Energy dispersed x-ray systems (EDS) and Eourier-transform infrared absorption (ETIR) are used by chemical microscopists for elemental analyses (EDS) of inorganic compounds and for organic function group analyses (ETIR) of organic compounds. Insofar as they are able to characterize a tiny sample microscopically by PLM, EDS and ETIR ensure rapid and dependable identification when appHed by a trained chemical microscopist. [Pg.334]


See other pages where For elements is mentioned: [Pg.11]    [Pg.111]    [Pg.252]    [Pg.309]    [Pg.1962]    [Pg.7]    [Pg.8]    [Pg.31]    [Pg.24]    [Pg.687]    [Pg.205]    [Pg.552]    [Pg.1044]    [Pg.1093]    [Pg.1094]    [Pg.262]    [Pg.53]    [Pg.215]    [Pg.353]    [Pg.271]    [Pg.276]    [Pg.131]    [Pg.356]    [Pg.164]    [Pg.333]    [Pg.328]   
See also in sourсe #XX -- [ Pg.11 , Pg.81 ]




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A Background Data for the Chemical Elements

A Pattern for the Elements

Absolute Method for a Single Element

An Essential Element for Life

An Essential Trace Element for Life

Analytical Methods for Elemental Se and Organo-Selenium

Analytical Methods for Elemental Te and Organo-Tellurium

Analytical methods for trace elements

Atomic Data for the Elements

Atomization, enthalpy change listed for various elements

Basic Elements for Energy Storage and Conversion

Biological Roles for Rare Earth Elements

Bonding models for the subvalent element chlorides

Boundary Element Method for Mold Cooling Analysis

Brief Summary of Atomic Spectroscopic Techniques Used for Elemental Analysis

CRMs for trace elements

Choice of Materials for Extruder Barrel and Screw Elements

Covalent radius of atom listed for various elements

Critical temperature listed for various elements and compounds

Deepwater Sampler for Trace Elements (Allowing Air to Mix with the Sample)

Design for reliability, finite element modeling

Detection limits for elements

Determination of isotope ratios for an element

Discrimination diagrams for basalts based upon major elements

Discrimination diagrams for clastic sediments using major elements

Discrimination diagrams for clastic sediments using trace elements

Electric field gradient expressions for transition metal elements

Electron Orbital Assignments for Some Transition Elements

Electron structure for elements

Electronegativity listed for various elements

Electronegativity values for the elements

Electronic matrix elements for

Element Contributions to Solid Heat Capacity for the odified Kopps Rule

Element Materials for HT Furnaces

Element Materials for LT Furnaces

Element production methods for

Elemental Acquisition in Humic Lakes Implications for Ecosystem Structure and Function

Elemental Design Analysis for Auxiliary Structures Associated with Nuclear Facilities

Elemental Quantification for Fingerprinting Enzymes

Elemental Sustainability for Catalysis

Elements essential for life

Elements for the calculation of PFH

Elements of the Finite Volume Method for Flow Simulations

Elements, test for

Essential Elements of Corporate Governance for Safety

Exchange Processes for Other Elements

Excited states for molecules containing d elements

Excited states for molecules containing main group elements

Faraday method for magnetic block elements

Finally a Name for Element

Finite element schemes for the integral constitutive models

Finite elements method for viscoelastic flows

Flame Tests for Elements

For prochiral elements

For trace elements

Formulas for Hamiltonian and Overlap Matrix Elements in the PPD Algorithm

Four Key Elements for Continuous Improvement

Fuel Element Designs for Gas-Cooled Reactors

Fuel Elements for the Gas-Cooled Fast Reactors

Gamma rays cross sections, for the elements

Gasless powders for delay elements of fuzes

Generic Microstructured Elements for Micro-mixer Devices

Graphic symbols for symmetry elements

Graphical symbols for symmetry elements

Ground state electronic configuration listed for elements

Group 2 Element Precursors for the

Group 2 Element Precursors for the Chemical Vapor Deposition

HEMICAL SHIFT CORRELATIONS FOR 13C AND OTHER ELEMENTS

Heat Capacity for Inorganic Compounds and Elements

ICP-MS with Chromatographic Techniques for Trace Element Speciation

ICP-MS with Chromatographic Techniques for Trace Element Speciation Studies

Ionic radii listed for various elements

Ionization energy listed for various elements

Jones Matrices for Simple Polarizing Elements

Keying element for transform function

Lewis-like structures for the d-block elements

Ligand design elements for iron catalysts

Linear inequalities for diagonal elements

Materials for Screw Elements

Matrix elements for

Matrix elements for composite systems

Mossbauer Spectroscopy for the Study of Elemental Speciation

Multi-element diagrams for igneous rocks

Multi-element diagrams for sediments

Names and Symbols for the Elements

Near-field LA-ICP-MS A Novel Elemental Analytical Technique for Nano-imaging

Nitrogen and Phosphorus Essential Elements for Life

Obturated Gasless Delay Element for 4 to 6 Seconds

Overview of Existing Basis Sets for Lanthanides and Actinide Elements

Pauling electronegativity values listed for various elements

Potential matrix elements for

Program for flow elements

Qualitative analysis for metallic elements

Qualitative analysis for the elements

Quantitative theory for nutrient element ratios

Quasispin and isospin for relativistic matrix elements

Radiotoxic element behavior for nuclear

Radiotoxic element behavior for nuclear waste disposal

Rare earth elements, and compounds pure, concentrated amalgams for

Rare earth elements, and compounds thereof pure, concentrated amalgams for

Recipes for Evaluation of Molecule-Fixed Angular Momentum Matrix Elements

Requirement of Mineral Nutrient Elements and its Estimation for Crops

Rules for Cataloging the Elements

Rules for matrix elements

Sample destruction for classical elemental analysis

Sample preparation for trace element and residue analysis

Sample preparation for trace elements

Selective sequential dissolution for trace elements in arid zone soils

Si-based reflection elements for ATR-FTIR investigations

Storage for the determination of trace elements

Structural Elements Required for Phosphorylation-Dependent Activation

Structural elements essential for

Superconducting critical temperature listed for various elements and compounds

Symbols for elements

Symbols for the elements

Symmetry elements for

Synchrotron Radiation as a Source for Infrared Microspectroscopic Imaging with 2D Multi-Element Detection

Technique for Commonly Determined Elements

Test Method for Determination of Additive Elements in Lubricating Oils by Inductively Coupled

Tests for Characteristic Elements

The Determination of Chemical Elements in Food: Applications for Atomic and Mass Spectrometry

The Use and Abuse of Trace Elements for Paleodietary Research

The selection of trace elements in igneous rocks for plotting on bivariate graphs

Third-row elements a case for expansion of the octet

Trace elements requirements for

What Elements Are Necessary for Our Health

Where Should Elements 43 and 75 Be Looked For

Wicks Theorem for the Evaluation of Matrix Elements

X-ray Spectroscopy for Elemental Analysis

X-rays cross sections, for the elements

XRF Methods Used for Elemental Analysis in Protein Fractions after Biochemical Separation

Zinc powder - sodium carbonate method for detection of elements

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