bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative film thickness determination by atomic force microscopy and ellipsometry for ultrathin polymer films
Authors: Gesang T. , Fanter D. , Höper R. , Possart W. , Hennemann O.‐D.
Published: May 2005

Ellipsometry and atomic force microscopy (AFM) were used to study the film thickness of continuous and discontinuous polymer films in the 1–20 nm thickness range on smooth silicon wafers and on structured aluminium substrates. The methods of exploiting AFM for thickness measurements with a high spatial resolution are described.

For continuous films, the AFM method is a direct one, i.e. it does not rely on any model. There is excellent agreement between AFM and ellipsometry in the 1–10 nm thickness range. Very small systematic deviations occur in this range but big deviations occur above 10 nm, and are discussed. The film preparation method, spin coating, was characterized to result in prepolymer films with a very homogeneous thickness.

Discontinuous films of 2–9 nm thick were also evaluated by both methods of thickness determination. In this case, for one of the AFM approaches a model has to be used too. The agreement between both methods ranged from very good to poor, depending on the kind of sample and on the kind of AFM determination method.
Oxidation of copper and mobility of copper ions during anodizing of an Al—1.5 wt.% Cu alloy
Authors: Habazaki H. , Shimizu K. , Paez M. A. , Skeldon P. , Thompson G. E. , Wood G. C. , Xhou X.
Published: May 2005

The mechanism of oxidation of copper at the alloy/film interface, and the subsequent migration of copper ions in barrier‐type films, has been examined for anodizing of an Al—1.5 wt.% Cu alloy with a prior chemical polishing treatment. Both chemical polishing and anodizing result in formation of a thin layer of alloy at the alloy/film interface, of ∼2 nm thick, that is highly enriched in copper. The layer is present immediately beneath the different types of film formed by chemical polishing and subsequent anodizing, and contains in both cases ∼6 × 1019 Cu atoms m−2. The amount of copper contained within the enriched layer of alloy is not significantly dependent upon the anodizing voltage. During anodic film growth, both aluminium and copper ions are incorporated into the film at the alloy/film interface, on average in their alloy proportions. However, the film is depleted in copper relative to the alloy because copper ions in the film migrate faster than Al3+ ions and, on reaching the film/electrolyte interface, are ejected directly to solution. The mechanism of oxidation of copper is proposed to depend upon the formation, through prior oxidation of aluminium, of copper‐rich clusters in the enriched layer of alloy at the alloy/film interface. Individual clusters are oxidized only on achieving a critical size. Consequently, copper is incorporated into the film discontinuously both in time and in position along the alloy/film interface. The films contain a high population density of flaws, which affects the film composition, the uniformity of ionic current, the faradaic efficiency of film growth, and the detailed distributions of copper ions within the films. However, the general features of film growth are compatible with the usual growth mechanism of anodic alumina, with transport numbers of Al3+ and O2−/OH− ions of ∼0.4 and ∼0.6, respectively.
The effect of organotin chlorides on the thermal stability of PVC
Authors: Wirth H. O. , Müller H. A. , Wehner W.
Published: May 2005

Metal chlorides formed from metal stabilizers under processing conditions have an influence on the thermal stability of PVC. Zinc chloride, e. g., has a strong destabilizing effect, whereas lead chloride behaves almost indifferently. Alkyltin chlorides however, have a stabilizing effect in as much as they cause a significant retardation of the thermal dehydrochlorination rate of PVC. Using 1‐chlorobutene‐2 as model substance, a chloro allyl isomerization could be proved caused by organotin chlorides under certain conditions. These results support a complex chemical isomerization concept to explain the stabilizing effect of organotin chlorides on PVC.
Stabilizing polyolefins is as easy as 1‐2‐3 (so why stop at 2?)
Authors: Dieckmann Dale
Published: May 2005

Most polyolefins require both free radical stabilization and acid neutralization. Conventional formulating follows a process of independent selection for stabilizers and neutralizers. This study shows that the use of a full factorial statistical design can facilitate concurrent optimization of neutralizer and stabilizer. A fractional factorial design did not provide sufficient information. Calcium lactate was shown to effectively improve YI color as well as neutralize acid residues.
Effects of thermal history on impact‐modified, high‐flow polycarbonate
Authors: Chung James Y. J.
Published: May 2005

Miles Inc. recently developed an impact‐modified, high‐flow polycarbonate to help meet the material requirements for thin wall applications. Melt temperature and heat aging were found to affect its impact strength, yield stress, and dynamic mechanical relaxations. The results are explained in terms of the presence of polycarbonate's high‐energy intramolecular conformations formed as a result of intermolecular packing effects during molding, their rearrangement to trans‐tans conformations, and the increased interlocking between neighboring chains during heat aging.
The influence of the extrusion process on the quality of unplasticized polyvinyl chloride (UPVC) pressure pipe
Authors: Benjamin P.
Published: May 2005

The gelation level attained in an unplasticized PVC pressure pipe determines the balance in the basic physical properties of strength, stiffness and ductility. In turn, the gelation level attained is dependent upon the processing conditions. Measurement of the gelation level can be used to control both the process and the pipe quality. It is a vital parameter for the development of the extrusion process for pressure pipe with the required long term strength and for the control of the pipe quality during production. Maintenance of the correct level of gelation can ensure a pipe quality well above the specification requirements thus giving an extra margin of safety in addition to the official safety factor.
Processing aids for chlorinated polyvinyl chloride
Authors: Deanin Rudolph D. , Mast Jonathan D.
Published: May 2005

Comparative studies of melt processability showed that chlorinated polyvinyl chloride (CPVC) had low melt index and high Brabender melt temperature and torque, as compared with conventional rigid polyvinyl chloride (PVC). Of 3 processing aids at 10 percent concentration, triphenyl phosphate increased melt index 30‐fold, fusion rate 10‐fold, melt temperature 20°C, and torque 31 percent in CPVC. Two other processing aids, an acrylic and a styrene/acrylonitrile copolymer, were less effective. Improvements in PVC were less dramatic than in CPVC. Overall, use of processing aids made CPVC processability equal or even superior to conventional rigid PVC.
Quality control in PVC compounding
Authors: Wedlake Gary Douglas , Banijamali Mostafa
Published: May 2005

A review of the criteria and benefits of a successful quality control program is presented from the perspective of PVC compounders. An application of Analysis of Variance in identifying the most significant sources of inconsistencies in the manufacturing operation is illustrated.
Application of SPC techniques to laboratory analysis
Authors: McNeese W. H. , Fenton J. T.
Published: May 2005

Efforts aimed at improving or monitoring quality must be based on measurement systems that are accurate and precise. The accuracy and precision of measurement systems can be controlled by the use of statistical methods, in particular by the use of control charts. A procedure has been proposed that involves determining the stability and precision of a measurement system. Comparison of the precision with overall process variability allows the processor to decide whether the measurement is adequate for monitoring the process.
Dimensional stability of exterior building products
Authors: Rabinovitch Elvira B.
Published: May 2005

Dimensional stability problems such as warpage, bowing and other changes in shape and size may occur when exterior building products (siding, windows) are heated by the sun. This paper describes the effects of material properties such as coefficient of thermal expansion, heat distortion temperature, modulus, and heat build‐up, caused by the sun, on dimensional stability of the exterior building products.
A new/old material as an engineering thermoplastic—PVC
Authors: Summers James W. , Dickerson James , Forsyth T. Henry
Published: May 2005

Polyvinyl chloride has been commercial for about fifty years. However, PVC is generally not thought of as an engineering thermoplastic. However, PVC can be engineered into many applications based on predictable engineering performance. PVC engineering data is presented.
PVC thermoplastic elastomers
Authors: Brookman Robert S.
Published: May 2005

The paper describes the development and properties of a new family of thermoplastic elastomers based on polyvinyl chloride.

Comparisons of the new products with traditional flexible PVC's will be presented, pointing up differences in specific gravity, low temperature properties, heat resistance, melt viscosity, and general physical properties such as tensile modulus and elongation.

The elastomeric properties of the new materials are explored and compared to some typical cured elastomers—chloroprene, chlorosulphonated polyethylene. The common thermoplastic elastomers based on block copolymers and polyurethanes are also considered in relation to the new compositions. Such properties as compression‐set, flex and fatigue resistance, oil and chemical resistance, weatherability, and performance at elevated temperatures are detailed.

The unique feature of this technology that allows one to tailor the surface characteristics from typically high PVC gloss to the fine dull satin finish of cured elastomers is discussed.
Hot‐fillable vinyl bottles
Authors: Gruber C. M. , Patterson J. R.
Published: May 2005

The use of plastic containers will grow 11% per year over the next ten years as metal and glass decline. Plastic is the material of choice for food containers in all areas of food processing including hot‐fill and retort packaging. This is due in large part to the strides that have been made in barrier property improvement, better manufacturing, and improvements in the economics, esthetics, and physical properties of plastics. Hot‐fill and retort packaging account for approximately 64% of the total packaged foods, and in the next 10 years this is expected to increase to 68%. Of the two, the hot‐fill method reportedly will gain in importance while retorting will decline by about 1% per year in effect pushing the growth in hot‐fill packaging to about twice that of the overall food packaging business. Since 1980, PVC bottles have grown from 100 MM lbs to more than 200 MM lbs of resin in 1987 (growth of approximately 15% per year). However, PVC bottles still represent only 7% of all plastic bottles and only 1% of all materials used to make rigid containers—an indication of great future potential. One of the serious disadvantages of PVC, however, is its low heat resistance which limits the service temperature of finished articles to about 70°C. Further penetration by PVC bottles can be accelerated by raising the heat resistance above the hot‐fill levels of 85°C–100°C. This would permit PVC to be used for many food applications such as fruit juices and table syrups. Now an additive is available that can be formulated with PVC to form miscible, transparent blends with increased service temperatures. The miscibility of the glutarimide acrylic copolymers in PVC allows it to significantly improve heat resistance without effecting the optical properties of the container. As a result, single layer PVC bottles can be made on conventional blow molding equipment that can be hot‐filled at 85°C–100°C, have glass‐like clarity, with good impact and moderate oxygen barrier resistance. The discussion will include guidelines for compounding the imide copolymer with PVC, properties attainable, and a look at the economics versus other hot‐fillable containers.
Reaction between HC1 and orthophthalates of lead in hot DOP without PVC, and stabilization in plasticized PVC
Authors: Michell E. W. J. , Shah D.
Published: May 2005

Reactions between hydrogen chloride, HCl, and either hydrocerussite, 2PbCO3. Pb(OH)2, or an orthophthalate of lead suspended in di(2‐ethylhexyl)phthalate, DOP, at 180°C are discussed as models of what should happen during the stabilization of PVC if thermal dehydrochlorination were to yield HCl. There is a sharp contrast between the products of these model reactions and those actually found in plasticized PVC containing basic lead compounds. This is taken to show that basic lead stabilizing regimes inhibit PVC thermal dehydrochlorination, actually preventing the formation of HCl. It is proposed that these stabilizing regimes function by a free‐radical mechanism which has been called “true stabilization” for ease of reference.
Quantification and prediction of processing damage in extruded PVC
Authors: Riley David W.
Published: May 2005

It is known that oxidation occurring during processing of some polymers like PVC and polypropylene causes their deterioration. This, in turn, detracts from its service life. This study shows how the extrusion process shear can be detected and followed stepwise and in effect be controlled. Separate identification of fragmentation and crosslinking levels are determined. Quantification of shearing, fragmentation, and crosslinking of the PVC melt is used to derive service life loss due to extrusion processing.
Comparison of the time‐temperature curing dependence of industrial and dry blend modified plastisols
Authors: Mendizabal E. , Candia J. M. , Jasso C. F. , Cruz L.
Published: May 2005

In this work PVC plastisol rotational molding formulations were characterized as a function of processing conditions. Temperature sweep runs in the 60 to 220°C range suggest the presence of different stages in the solidification process, marked by the crossover of storage (G′) and loss (G″) moduli. Viscoelastic properties as a function of time were measured at different processing temperatures (in the 80 to 220°C range). Ultimate strength, ultimate elongation, and solvent resistance of the formulations after processing were also measured to evaluate performance.
Molecular weight and solution viscosity characterization of PVC
Authors: Skillicorn D. E. , Perkins G. G. A. , Slark A. , Dawkins J. V.
Published: May 2005

As a means of developing the most accurate possible Mark‐Houwink relationship possible for PVC, the literature Mark‐Houwink coefficients for the weight average molecular weight (MW) of PVC in THF are plotted and the derived “grand average” Mark‐Houwink relationship (K = 15.56 × 10−3 ml/g, a = 0.7690) is shown. High pressure‐size exclusion chromatography (HP‐SEC) data from two independent laboratories was used along with the “grand average” Mark‐Houwink coefficients to calculate absolute number of average molecular weight (MN) and weight average molecular weight values for PVC. An easy‐to‐use table has been developed to detail the relationships between MN, MW, K value, and inherent viscosity (I. V.).
Plasticizer structure/performance relationships
Authors: Krauskopf L. G.
Published: May 2005

Plasticizers for poly(vinyl chloride) may be organized into eight chemical families and by seven key performance criteria. Cost‐effective general‐purpose phthalates provide a base line for comparing all other plasticizers. The wide range of performance characteristics associated with various phthalate isomers substantiates the large proportion of phthalate esters that are utilized as plasticizers. This article summarizes plasticizer structural/performance relationships using quantitative comparisons of cost, plasticizing efficiency, plastisol solvation characteristics, dryblending, volatility, and low temperature performance properties in PVC. Some generalizations are also made concerning structural effects of the alcohol isomers used in the syntheses of the various types of plasticizer esters.
Effect of crystallinity on PVC physical properties
Authors: Marshall R. A.
Published: May 2005

Crystallinity in PVC contributes significantly to the strength and resiliency of the polymer. Two types of crystallites have been described: a primary crystallite in the virgin powder state pictured as a platelet or flat needle‐like lamellar crystallite, and a secondary, fringed micellar crystallite from melts or solutions. Both crystallites create loose, crosslinking networks. The secondary crystallite forms when plastisol melts are cooled or solutions are gelled. Crystallites exert a major effect on rheological properties. The thermal destruction of the primary crystallite networks in the melt phase results in a decrease in elastic modulus. Cooling from the fused state creates secondary crystallites that affect tensile and elongation.
X‐ray spectra calculator
Authors: Adam J.
Published: May 2005

The calculator is an aid to identification of lines in X‐ray emission spectra. It is designed to solve the well‐known Bragg equation: nλ=2d sinθ Principal X‐ray emission wavelengths (λ) of elements of atomic numbers Z=6 to 95 and lattice spacings (2d) of crystals commonly used in analysis are entered as data. The display of data is so arranged that line overlaps of the first and higher orders (n) of reflection can be seen at a glance for any spectrometer angle (θ or 2θ).
Comparison of phosphorus in some standard rocks by X‐Ray fluorescence analyses using the Ge (111) and PE crystals
Authors: Fregerslev Wilson S. J. R.
Published: May 2005

Phosphorus has proved to be one of the most difficult elements to determine precisely in rocks by X‐ray fluorescence analysis. This is partly because of its low concentration in rocks, and because of interference from Ca 2Kβ and its associated escape peak when using the common crystals PE or EDDT. The Ge (111) crystal does not give any second order reflection. A comparison of phosphorus determined in some geological materials using PE crystal and electronic discrimination, PE crystal and manual discrimination and Ge (111) crystal is given.
Synthetic corundum as an X‐Ray monochromator
Authors: Belt R. F.
Published: May 2005

Single crystal boules of hexagonal α‐AI2O3 (corundum) were grown by the Czochralski method. The resulting size and crystal quality are appropriate for use as X‐ray monochromators. Eight corundum plates of various 2d spacings were fabricated and evaluated in both an X‐ray diffractometer and emission spectrometer. The corundum data were compared with crystals of ADP, Si, CaF2, Ge, NaCl, LiF, quartz and topaz. For X‐ray diffraction with Cu Kα the corundum (1014) cut is of highest intensity. It is about equal to all other crystals except NaCl (200) and LiF (200). The latter have respectively about 4 and 9 times the corundum intensity. In emissior spectroscopy at wavelengths of 0.1 to 0.5 Å, the corundum (0330) cut is superior to quartz (2023) and topaz (303). The intensity is 2 to 4 times higher for corundum. High resolving power can be attained by the corundum (1456) cut with 2d=1.660 Å. Data and applications are presented for this particularly useful crystal.
Analyse des Roches par une Méthode de Fluorescence X comportant une Correction Précise pour l′Effect interélément
Authors: Tertian R. , Géninasca R.
Published: May 2005

Nous avons appliqué la méthode de double concentration, dont nous rappelons brièvement le principe, à la détermination précise des constituants majeurs et mineurs, soit Fe2O3 MnO, TiO2, CaO, K2O, P2O5, SiO2, Al2,O3, MgO et Na2O, dans les roches silicatées ou apparentdées. Dans ce cas, la technique de la double mesure permet de corriger pour l'effet interélément avec une précision relative théorique de l'ordre de quelques dixièmes de pour cent et nous avons pu grâce des précautions particuliéres en ce qui concerne la préparation des “perles” vitri‐ fiées et la mesure des intensités nettes, porter la precision pratique à un niveau comparable. Une étude exploratoire alors menée sur quatorze roches étalons (dont sept du Centre de Recherches Pétrographiques et Géochimiques de Nancy et sept de l'U.S. Geological Survey à Washington) nous a conduits à des résultats très satisfaisants, en ce sens qu'ils concordent généralement avec les valeurs “recommandées” dans la limite de ±1 pour cent, voire mieux, en valeur relative. Un petit nombre de valeurs recommandées ou proposées, dans le domaine des très faibles concentrations, peuvent même être contestées ou améliorées.

Cette méthode simple et directe qui nous dispense d'avoir recours à toute espèce de coefficients d'influence ou de para‐ mètres fondamentaux, ainsi qu'aux machines, est quasi‐absolue. On peut I'employer avec avantage non seulement pour l'analyse des roches et des composés similaires, mais aussi et même avec une précision encore accrue pour l'analyse des minerais en général.
Comparison of some procedures for X‐Ray fluorescence analysis of metallurgical slags
Authors: Carlsson G.
Published: May 2005

Several procedures for X‐ray fluorescence analysis of slag including acid solution and fusing methods are compared. For eliminating erros due to inter‐element effects, heavy element addition and calculation methods are considered. Data of precision and accuracy are given for eleven different combinations. For routine operation fusing with borax and casting of a bead is recommended. Fusion in a semi‐automatic bead production machine is time‐saving, simple and more precise than manual operation and is described in some detail.
K emission and absorption spectra of nitrogen with the electron microprobe
Authors: Romand M. , Solomon J. S. , Baun W. L.
Published: May 2005

The K soft X‐ray emission profile of nitrogen in the vanadium nitride VN has been investigated with an electron microprobe. It is shown that this instrument is capable of sufficiently resolving the N K band to provide information about the filled states of the valence band. Moreover, with this same compound, the first K absorption spectrum of nitrogen has been obtained by a self absorption method. VN is only an experimental example. To find the complete picture of the electronic band structure of solid materials, similar emission and absorption spectra of nitrogen in some other interesting compounds can now be surveyed with the electron microprobe.
On‐stream energy dispersive X‐ray analysers
Authors: Carr‐Brion K. G.
Published: May 2005

The advantages and disadvantages of on‐stream energy dispersive analysers for X‐ray fluorescence and diffraction have been examined. These include factors such as ease of sample presentation, selection of exciting X‐ray energy, stability, count rate performance and microphony. Finally a number of applications and feasibility studies have been described including work for the cement, mineral processing, extractive metallurgy and related industries.
High intensity excitation sources for X‐ray energy spectroscopy
Authors: Porter D. E.
Published: May 2005

The use of secondary targets with commercially available high power X‐ray spectroscopy tubes has been investigated as a means of providing an excitation source for X‐ray energy spectroscopy. A comparison has been made between the secondary target mode of excitation and the use of the tube directly. Results from this comparison show the superiority of the secondary target technique. Examples of analysis using the secondary target excitation are given to illustrate the high data rates and low background this technique has to offer.
A new approach to the study and control of interelement effects in the X‐ray fluorescence analysis of metal alloys and other multi‐component systems
Authors: Tertian R.
Published: May 2005

Accurate fluorescent intensities of a number of binary and ternary alloys have been calculated by relying on the classical expressions of primary and secondary fluorescence and assuming standard spectral intensity distributions for the primary radiation. It could then be shown that under polychromatic excitation the enhancement effect on the one hand, and on the other hand, the absorption effect with the complications (drift of equivalent wavelength) related to polychromatic radiation, became very much alike on practical terms, apart from generally opposed signs. Both effects could then be dealt with in a homogeneous way and a simple method was derived using (K − 1) coefficients ‐ see definition in the text ‐ which are fixed from a careful study of binary compositions.

Moreover, making provision for fluorescence ‘crossed effects’, the principle of a general and accurate procedure was then established to the end of computerized non‐destructive analysis. The name of ‘generalized iteration method’ is proposed for this procedure.
The evaluation of the use of a scanning electron microscope combined with an energy dispersive X‐ray analyser for quantitative analysis
Authors: Blum F. , Brandt M. P.
Published: May 2005

This paper describes an evaluation of the use of a scanning electron microscope to perform a rapid total analysis under secondary electron image conditions using a commercial energy dispersive X‐ray analyser. Problems encountered with overlapping intensity peaks and interference by the solid state Si (Li) detector are discussed. Elements heavier than sodium are detectable in metallic and geological samples and the total analysis of oxides requires only pure elements as standards.
Ein Beitrag zur Optimierung der Röntgen‐Spektralanalyse durch Verwendung spezifischer Zählrohrgase
Authors: Loch G.
Published: May 2005

Bei manchen Analysenproblemen in der RFA reichen das Auflösungsvermogen des Kristalls und die Impulshöhendiskriminierung nicht aus, um den Einfluss von Storlinien zu unterdrücken. In vielen dieser Fälle kann durch Verwendung spezifischer Zählrohrgase eine erhebliche Verbesserung des Signal‐Untergrund‐Verhältnisses erreicht werden.
Computerized correction for element inter‐action in X‐ray fluorescence analysis with special reference to copper, chromium and arsenic in solutions and preserved wood
Authors: Reistad T. , Pettersson B.
Published: May 2005

The Boliden X‐ray computer system is an ‘on‐line’ combination of an X‐ray spectrometer and a computer. With the X‐ray computer system a rapid and accurate determination of copper, chromium and arsenic in solutions and preserved wood has been accomplished. A functional model for interelement corrections has been tested within the actual concentration range 0 to 2%. The 2σ values for the determination of copper, chromium and arsenic have been calculated to ±1%rel. for solutions. The corresponding 2s̀ value for treated wood is ±2.5% rel. of which at least 1.5% is due to the sample preparation error.
A critical survey of mixing, dilution and addition methods and addition methods and possible extensions of the theory. Part I
Authors: Gwozdz R.
Published: May 2005

The commonly used equation relating the intensity of characteristic X‐radiation to the concentration of the element to be determined contains three unknowns. By chanfing the concentration of this element in two additionally prepared samples further data are obained permitting the derivation of two more equations. Solution of these three equations by algebraic or graphical methods yields the concentration of the elemen. Formulae have been derived desribing ten experimental variants of this principle. Three of these formulae are similar to those described by sherman and Tertian. The other two describe the semi‐emipirical methods of addition, and mixing‐dilution developed by Jones.

The experimental data for eleven elements involving ten kα lines, two Kβ lines and one Lα line were obtained using two X‐ray units. The samples were investigated in the form cf liquid, powder pellet, glass disc and powdered glass disc. Only the three most general formulae have used in the calculations. Results show absolute percentage deviations within 1 to 3%.
The on‐stream analysis of hematite ore fractions using radioisotopes
Authors: Reed D. J. , Dalton J. L. , Gillieson A. H.
Published: May 2005

Hematite ore fractions in the form of circulating slurries of various solids content were analyzed for iron and silicon, their principal metallic constituents, to determine the relationships and factors significant to such analyses. Radioisotopes were used to excite the characteristic radiations which were measured nondispersively. Counts were also taken for the exciting radiations.

The measured intensities for Fe Kα and Si Kα were corrected by backscatter and absorption factors derived by the comparison of counts from the slurries to those from water. Regression lines were used to convert all counts to a 40% solid basis.

The iron content of the ore fractions was determined with a standard error of less than 2%. The determination of silicon was not satisfactory at low concentrations because all components of the slurries absorb Si Kα strongly.
Determination of overall system efficiency of an energy dispersive X‐ray fluorescence spectrometer using a bremsstrahlung exciting source
Authors: Cothern C. R. , Manuel H. L. , Millette R. J.
Published: May 2005

Four independent techniques for quantitatively calibrating an energy dispersive X‐ray fluorescence system are compared. These include commercially available powder standards, vacuum deposited standards, laboratory developed powder standards and a semi‐theoretical method. A technique is presented for using the latter method in the case where the exciting radiation is bremsstrahlung. These methods are discussed and their resulting efficiency values compared. The most complete, most reliable and easiest method is the semi‐theoretical method. Single compound powders of standard chemicals can be used one at a time for periodic checks of the system.
Role of crystallographic polar surfaces in X‐ray spectrometry
Authors: Bhalla A. S.
Published: May 2005

GaSb single crystals have been used to demonstrate the role of crystallographic polar surfaces in double crystal X‐ray spectrometry. Intensity is higher for the pair of (111) surfaces, whereas the half peak width is smaller for the pair of (111) surfaces.
An X‐ray fluorescence method for analysis of lead zirconate‐titanate compositions
Authors: Murata Michihiro
Published: May 2005

An X‐ray fluorescence method for the determinatios of lead, titanium, zirconium and strontium oxides in lead zirconate‐titanate has been developed. The method is a simple empirical correction procedure and requires only one standard containing all the elements analyzed. Moreover, the method does not require prior determination of correction factors obtained by a complex calculation, a multiple regression procedure, or from use of a considerable number of well analyzed standards.
A method for predicting X‐ray fluorescence anomalies in multiphase metal alloys
Authors: Kemper M. A.
Published: May 2005

The problem presented by a multiphase metal system is studied, where one element is able to migrate from one phase of the alloy to another due to different states of heat treatment. The experimental work was performed on the simple Al + Si system; the results demonstrate that in extreme cases relative analytical errors of 400% may be accumulated if the ‘metallurgical history’ of sample and standard is neglected. The Claisse‐Samson particle size formulae for powder samples are applied to the grain size of the phases present in the allows with good agriment, and may be used to predict whether analytical problems are to be expected.
On obtaining consistent solutions of the equations for quantitative analysis by X‐ray fluorescence spectrometry
Authors: Boniforti R. , Buffoni G. , Colella C. , Riccardi R.
Published: May 2005

Many of the equation systems proposed for calculating elemental composition by X‐ray fluoresence spectrometry are overdetermined. In the present work an attempt has been made to overcome this difficulty by reducing the problem outlined to an eigenvalue one.
Eine Methode Zur eichprobenfreien quantitativen Röntgenfluoreszenzanalyse
Authors: Drabseh Salih
Published: May 2005

Es wird eine Methods zur eichprobenfreien Rötgenfluoreszenzanalyse beschrieben. Der Vergleich mit Reinelementstandards kann dabci entfallen, da das Zählratenverhältnis von je zwei Reinelementen als Gerätefunktion definiert wird. Durch Verwendung der Zählratenverhältnisse jeweils zweier Elemente der unbekannten Probe wird zusammen mit der Methode des variablen Beobachtungswinkels die quantitaive Zusammensetzung erhalten.
Préparation Automatisée de Perles pour l'Analyse par la Fluorescence de Rayons X
Authors: Wittmann A. , Chmeleff J. , Herrmann H.
Published: May 2005

Description d'un appareil automatique de préparation des échantillons pour l'analyse par fluorescence de rayons X, La technique est basée sur la mise en soluation solide de l'échantillon en uve de l'obtention d'une perle directement analysable.

L'appreil est composé de deux fours HF, I'un pourla fusion, I'autre pour la coulée Les récipients de fusion et de coulée sont en alliage platine+ or+ rhodium. La seéquence automatique de préparation dure huit minutes.

Une application á I'anlyse de minerais de fer reches par miscen solution dens le tétraborate de sodium illustre les reproductibilités de préparation que I'on peut atteindre avec ce matériel (écart type de reproductibiliteé égal á 0,15% de Fe au niveau de 60%).
X‐ray spectrometry of Al + Ni powder compacts and alloy thin films
Authors: Duz̆ević D. , Gaćes̆a T.
Published: May 2005

This paper reports on expeeriments to determine the composition of thin aluminium + nickel films. The techniques used were similar to those described by both Rhodin and Weyl but for reasons of simplification of the calculations involved, the effective wavelength concept was employed. Fluorescence measurements were also made on aluminium + nickel powder compacts of known composition. The comparison of measured intensities from powder compacts and thin films revealed a strong particle size intensity dependence.
A time saving approach to peak spectra analysis
Authors: Grote R. , Cothern C. R.
Published: May 2005

In X‐ray fluorescence, as well as other quantitative methods for determining trace metal concentrations, computer methods for extracting characteristic peaks from background are very important. Cases where background is large and nonlinear, or there are overlapping peaks, present difficulties in the development of simple computer programs which give an accurate analysis of the peak. The method of analysis that will be described here was developed to meet these demands. The basic concept is simple, and good accuracy and reproducibility are achieved in samples with large nonlinear background, as well as overlapping peaks. The analysis is essentially independent of background.
Experiences with automated X‐ray fluorescence spectrometry in the analysis of refractory metals
Authors: Ortner H. M. , Lassner E. , Hertroys P.
Published: May 2005

This paper reflects three years' experience on the part of two of the authors with the Philips PW 1220/C X‐ray fluorescence spectrometer in combination with the Philips software packages ‘X‐ray 21’ and ‘X‐ray 10’ for the analysis of molybdenum, tungsten and their alloys.

Of the ten analysis programs developed, three are discussed in detail. They embrace the determination of main constituents in the region of 100 per cent as well as the determination of traces in the ppm range after trace‐matrix separation. For trace analysis the standard software had to be modified in order to measure several blanks and standards and to overcome other shortcomings in the original program. The arithmetical means of blanks and standards are used for the calculation of linear calibration functions. This new, more versatile X‐ray 10 software package extends the applicability of the standard X‐ray 10 system to trace analysis. It also proved advantageous for the analysis of minor constituents in aqueous solutions.
Analysis of powdered materials by X‐ray fluorescence spectrometry. Evaluation and correction of the interferences
Authors: Frigieri P. , Trucco R. , Caretta E.
Published: May 2005

A method is described for the direct quantitative analysis by X‐ray fluorescence spectrometry of some elements in powdered materials collected on inert filters. In order to gain a view of the general applicability of the method, the effects of the interferences due to the nature of the analytical samples were studied and verified, and a possible means of overcoming them is proposed. The principal factors that effect the interference phenomena were found to be variation of the X‐ray path into the sample due to different deposit thickness, different X‐ray beam penetration owing to sample density, and absorption and enhancement of the characteristic radiation by the combining elements. The aim of this work is to propose a method which eliminates the drawbacks due to the matrix absorption effects, whatever their origin. A better understanding of the phenomena, the mathematical treatment of the basic principles and the use of experimental artifices, allowed us to achieve optimized conditions for analysis, suitable for general routine applications.
Indium antimonide as an X‐ray monochromator
Authors: Gohshi Y. , Hirao O. , Murata M. , Tanoue T. , Tsuruoka M.
Published: May 2005

A single crystal of indium antimonide (zinc blende type InSb) was evaluated as an X‐ray monochromator. The long 2d spacing of 7.481 Å makes it possible to diffract Si K α in an ordinary X‐ray emission spectrometer. The indium antimonide data were compared with crystals of EDDT, Ge and LiF. Indium antimonide shows seven times higher Si Kα intensity than EDDT. It also has very low second order reflection. A low coefficient of thermal expansion (4.9 × 10−6 °C−1), together with its very stable chemical nature will facilitate high precision measurement ranging from 14Si to 46Pd(Kα), 38Sr to 92U(Lα) and 74W to 92U(Mα).
Nickel‐59 excitation source for X‐ray fluorescence analysis of carbon and low alloy steels
Authors: Gehrke R. J. , Helmer R. G.
Published: May 2005

The use of Nickel‐59 as an excitation source for the X‐ray fluorescence analysis of carbon and low alloy steels has been investigated. Nickel‐59 has a half life of 80 000 y and is essentially a pure source of cobalt K X‐rays. It is ideal as an X‐ray source for field systems because the encapsulated source is small, rugged and requires no external power or maintenance. The prototype system require ∼2½ minutes to obtain a manganese analysis, and 15 minutes to determine vanadium, chromium and manganese concentrations. These times could be shortened about a factor of 40 with a more intense excitation source and a larger area detector. The feasibility of portable field systems is discussed.
Zinc trace analysis in InSb by proton‐induced X‐rays
Authors: Pabst W. , Schmid K.
Published: May 2005

The zinc concentration in an epitaxial layer of InSb was measured by proton excited X‐rays. For the determination of zinc concentration, the X‐ray yield was compared to that from known zinc concentrations. As layer thickness, stopping power and X‐ray absorption must be taken into account, a general mathematical evaluation was developed. In an appendix, the derived equations are shown to allow a layer thickness determination. The calculated values agree quite well with the experimental results.
Recent experimental values for K shell X‐ray fluorescence yields
Authors: Freund H. U.
Published: May 2005

A table is presented summarizing recently available data of experimentally determined K shell X‐ray fluorescence yields.
On obtaining consistent solutions of the equations for quantitative analysis by X‐ray fluorescence spectrometry. A program for use when the power method fails
Authors: Boniforti R. , Buffoni G. , Riccardi R.
Published: May 2005

For the case where the power method fails to give a non‐negative eigenvector for system (1) a program has been set up to calculate all the eigenvalues and eigenvectors of system (1).
Energy dispersion quantitative X‐ray microanalysis on a scanning electron microscope
Authors: Servant Jean‐Michel , Meny Lucienne , Champigny Michel
Published: May 2005

In this work quantitative measurements performed by EDX on SEM, abd by WDX on EPMA are compared. The commerical SEM has been improved by the addition of a beam regulation and an anticontamination device. The spectra are detected by a Si(Li) detector (FWHM = 180 eV) and digitalized by an analog‐to ‐digital converter. The spectra obtained are treated by an on‐line minicomputer PDF 11/05 included in a NS 880 system. A teminal byilt‐in magnetic tape cassette functions as a storage device for the computer. The dialogue between the system and the operator and programmation are possible through a keyboard and a visualization screen. The programs used include: spectrun smoothing, background subtaction selected area totalizing and spectrum stripping. The count rate is maintained at the order of 3000 counts per second to avoid pulse pile up and dead time losses. The experimental intensities are then corrected through a ZAF method by the profgram C ø R on an IBM 360. Binary alloys TiA1, FeA1, ZrNi, NbA1 and TiZr have been studied by K and L lines at different values of the excitation voltage. Alloys MgA1, FeMn and TiVCr Presenting overlapping peaks, and a glass, have also been analysed. The errors, advantages and limits of the method are discussed: in a homgeneous bulk material the minimum detectable limit calculated by C(DL)A = 3I CA/IA is of the order of 0.03 wt % with WDX and 0.2 Wt % with EDX for 100 seconds counting time. It could be improved by increasing the counting time and by using better electronics. The precision of the result is comparable to that obtained by WDX. With EDX on SEM the rapid and simultaneous quentitative micro analysis of all the elements of 11 < Z ≤ 92 can be performed with good precision. This method is very interesting for thin targets and dispersion of precipitates.
Intercomparison of trace element determinations in simulated and real air particulate samples
Authors: Camp David C. , VanLehn Allan L. , Rhodes John R. , Pradzynski Andrej H.
Published: May 2005

Results are presented of an intercomparison study involving twenty‐two investigators who collectively used six different analytical techniques. Synthetic dried solution and particulate deposits were prepared and, together with natural aerosol samples, were used for the study. Analytical techniques utilized by the participants were wavelength dispersive X‐ray spectometry, two different energy dispersive X‐ray techniques, atomic absorption spectrometry, emmision spectroscopy and neutron activation analysis. Results showed that energy dispersive X‐ray spectrometry, is a reliabnle technique for the multi‐element analysis of particulate matter collected on filter media. It reported the most elemental determinations per man‐hour invested and provided satisfactory accuracy for the quantitative determination of elements pottassium (Z = 19) and above, with somewhat larger errors for elements down to aluminium (Z = 13). The study demonstrated the need for a better understanding and practical application of particle size corrections for lighter elements. The non X‐ray techniques were neither well represented nor strongly supported by the study.
Determination of gadolinium in uranium by X‐ray fluorescence analysis
Authors: Boniforti R. , Riccardi R.
Published: May 2005

A method is presented discussing the determination of gadolinium in Gd2O3 + UO2 pellets. The relative accuracy ranges between 1 and 2%.
Theoretical correction of inter‐element effects: System iron + nickel + chromium
Authors: Budesinsky Bret W.
Published: May 2005

The theoretical relationship between relative intensity and concentration is used for the estimation of influence coefficients for the Rasberry‐Heinrich, Claisse‐Quintin and Lachance‐Traill method. Those coefficients are used to evaluate Rasberry‐Heinrich, Beattie‐Brissey and Shiraiva‐Fujino measurements in the system of iron + nickel + chromium. An improved program, printing the average error of calculation per element had containing safeguards to avoid the divergence of iteration, is used for computation. The Rasberry‐Heinrich method gives the best results. Theoretical reasons are given in explanation.
A design to minimize exposure to scattered X‐ray radiation
Authors: Shepard R. L.
Published: May 2005

A design is described which conforms to OSHA recommendations for good radiation protection procedures. This design can be used on most units where X‐ray optics are exposed to the atmosphere. It proves sufficient and should make most nonvacuum X‐ray units comply with today's recommended dosage levels. A survey of our instrument gave results well below the maximum permissible level of 2.5 milliröntgen per hour for scattered radiation at a distance five centimeters from the housing surface. The detected scattered radiation was in the range of 0.03 milliröntgen per hour, which is within the limits of normal background radiation.
X‐ray spectroscopic study of some cobalt chalcogenides
Authors: Kondawar V. K. , Mande C.
Published: May 2005

The position, shape and the extended fine structure of the cobalt K absorption discontinuity have been studied in the pure metal and in its four chalcogenides, CoO, CoS, CoSe and CoTe, using a forty centimetre diameter bent crystal X‐ray spectrograph. It has been found that the discontinuity shifts towards the high energy side in the chalcogenides and that the chemical shift ΔE depends upon the effective ionic charge on the absorbing atom. The fine structure within the main discontinuity is discussed on the basis of band structure and molecular orbital diagram, while the extended fine structure is interpreted on Lytle's theory. The results obtained throw light on the chemical bonding prevalent in these compounds.
A method of producing mounted thin windows for X‐ray spectrometer flow counters
Authors: Borley G. D. , Bullen G. , Hara K. O'
Published: May 2005

Thin windows for X‐ray spectrometer flow counters can be produced by stretching unorientated polypropylene film. A piece of the stretched film is clamped into a holder and pressed onto a copper ring made from thin copper sheeting. The mounted window is then suspended in a high vacuum coating unit and flashed with aluminium to a thickness of approximately 20 nm.
A comparative study of techniques for quantitative analysis of the X‐ray spectra obtained with a Si(Li) detector
Authors: Statham Peter John
Published: May 2005

With the appropriate excitation, a specimen will emit an X‐ray spectrum where the characteristic line intensities are strongly dependent on the elemental composition. The measurement of these intensities thus affords a method of accurate quantitative elemental analysis. A digitized record of the spectrum may be obtained using a lithium drifted silicon detector, associated electronics and some storage medium. The recorded data is the original spectrum convoluted by the appropriate instrumental function. This paper describes several procedures which may be applied to this data to obtain accurate estimates of the individual X‐ray line intensities, mainly with reference to the spectra obtained by electron excitation of thick specimens. The choice of a particular procedure depends on the quality of the data acquistion system, and the likely systematic errors which have been calculated for illustrative examples with special reference to the effects of drift and resolution changes in the electronics. Background subtraction techniques involving interpolation, extrapolation and filtering are discussed, together with methods for deconvolution of overlapping peaks, in particular least squares regression. A versatile new procedure, iterative stripping, is presented which simultaneously accomplishes background subtraction and peak deconvolution.
Determination of yttrium and niobium on standard silicate rocks by X‐ray fluorescence analyses
Authors: Leoni L. , Saitta M.
Published: May 2005

Eleven international standards [U.S.G.S. Standards. G‐2, GSP‐1, AGV‐1 and BCR‐1; C.R.P.G. standards: GA, GH, BR and Mica‐Fe; A.N.R.T. standard: DR‐N; G.S.J. standards: JG‐1 and JB‐1] have been analysed by X‐ray fluorescence for niobium and yttrium. Coefficients for full matrix effect correction are reported.