bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interactions between ants and non-myrmecochorous diaspores in a tropical wet forest in southern Bahia, Brazil
Authors: Santana Flávia Delgado , Cazetta Eliana , Delabie Jacques Hubert Charles 
Published: January 2013

Abstract:Interactions between ants and non-myrmecochorous diaspores occur frequently on the forest floor and the results of these interactions (e.g. diaspore cleaning or removal) will often depend on the morpho-chemical characteristics of the diaspores. We conducted two different experiments with seven plant species in the north-eastern Atlantic forest, Brazil. To evaluate whether ant interactions decrease diaspore persistence time on the forest floor, we established sample stations by placing five diaspores of each species spaced every 10 m along a transect and monitored ant interactions over a 24-h period. We also compared diaspore removal by ants and vertebrates through a paired experiment. We monitored removal of the seven plant species in treatments where ants were excluded and treatments where vertebrates were excluded. We recorded 332 ant–diaspore interactions, most resulting in ants cleaning diaspores in situ. Persistence of diaspores on the forest floor varied greatly among studied species and was less than 50% for three species. Ants also removed more diaspores than did vertebrates. Number of diaspores removed by ants was greater for small diaspores and with high lipid concentration. Ant–diaspore interactions may not always exert a positive influence on plant recruitment for diaspores with poor nutrient concentration. Consequently, ants may play a disproportionately important role as secondary dispersers in tropical forests.
Edward Schillebeeckx's Creation Theology as a Resource for Ecological Ethics
Authors: Olson-Bang Erica 
Published: January 2013

ABSTRACTAs the global community becomes increasingly attuned to the disastrous consequences of our long-standing environmental prodigality, Christians and Christian theologians are cultivating theological and ethical responses to the ecological crisis with the goal of fostering life-giving understandings of creation and ecophilic lifestyles. While many theologians and ethicists have heeded this call to read the signs of the environmental times, Schillebeeckx's creation theology remains an underutilized resource for developing an ethical response to this contemporary crisis. This article seeks to offer Schillebeeckx's theology of creation as fertile soil for nurturing an ecological ethic. This article highlights Schillebeeckx's growing ecological concerns, illustrates the connection between Schillebeeckx's theology of creation and his ecological consciousness, and transposes Schillebeeckx's emerging ecological themes into the register of environmental ethics. This ecological ethics emphasizes co-creativity with God in creation, ecological asceticism, following Christ's creational praxis, and actualizing the present practice of the coming kingdom of God.
X-ray powder diffraction data for two new N-substituted 3,4-dihydrospiro-2(1H) quinolines
Authors: Henao J. A. , Palma A. , Kouznetsov V. V. , Delgado J. M. 
Published: January 2013

The X-ray powder diffraction patterns for two N-substituted tetrahydroquinolines are reported. N-(α-Chloroacetyl)-6-methoxy-3,4-dihydro-4-methylspiro[cyclohexane-1′,2(1H)quinoline], C18H24ClNO2, and N-(α-chloroacetyl)-6-chloro-3,4-dihydro-4-methylspiro[cyclohexane-1′,2(1H)-quinoline], C17H21Cl2NO are monoclinic, with refined unit cell parameters a=1.4471(3), b=0.9600(4), c=1.1948(3) nm, β=93.21(2)°, V=1.6573(6) nm3, Z=4, Dx=1.29 gcm−3, and a=1.4487(3), b=0.9878(2), c=1.1390(2) nm, β=91.66(2)°, V=1.6294(4) nm3, Z=4, and Dx=1.32 gcm−3, respectively, with space group P21/n (No. 14).Key words: powder diffraction data, spirotetrahydroquinolines.
An introduction of chemical structure coding in the X-ray Powder Diffraction File
Authors: Lianhu Wei , Yunde Xiao , Jinbei Zhang , ShaoFan Lin 
Published: January 2013

A special computer storage method for chemical structures is illustrated in this article. With an improved method of two-dimensional connection table and topology, we can fit almost all chemical structures and display them very conveniently. We have used this method in the PDF (X-Ray Powder Diffraction File) database, which contains many special structures.Key words: database, computer application, chemical structure
Computer Automation of Structure-Sensitive Search-Match Algorithm for Powder Diffraction Analysis
Authors: Filsinger D. H. , Frevel L. K. 
Published: January 2013

AbstractThe Semi-manual Structure-sensitive SEARCH-MATCH procedure [Frevel, (1982), Anal. Chem. 54, 691–697] has been automated for the Hewlett-Packard HP 3354 Computer. The software is coded in the interpretive HP LAB BASIC II language. A core file of 1026 selected powder diffraction standards has been compiled covering the common crystalline phases encountered in industry, the ubiquitous crystalline minerals, and prototypes of the more frequently found crystal structures. Solid solutions can be readily identified.
Chemical Analysis by X-Ray Diffraction: Classification and Use of X-Ray Diffraction Patterns
Authors: Hanawalt J. D. , Rinn H. W. , Frevel L. K. 
Published: January 2013

Editor's Note: As part of our plan to reprint previously published papers of great historical interest, the editorial board is pleased to reproduce the following paper by Hanawalt, Frevel and Rinn. This paper was originally published in Volume 10 (1938) of the Analytical Ediction of “Industrial and Engineering Chemistry” and is considered by most diffractionists to be the classic work in qualitative identification of multiphase polycrystalline material. The original publication carried a foreword written by the editor of Industrial and Engineering Chemistry. This foreword ended with this prophetic statement:“There is reason to believe that this publication, which is made possible in this form by the generous financial assistance of the Dow Chemical Company, will serve to bring this method of analysis into general use in industrial and consulting analytical laboratories.”
Powder Diffraction Data for Trans-Bis (Dimethylphenylphosphine) Bis (Pyrazole) Platinum, [Pt(C3H4N2)2{P(CH3)2(C6H5)}2] and Trans-(Tricyclohexylphosphino)-(Triethylphosphino) Platinum(II) Chloride, PtCl2P2C24H48
Authors: Mullica D. F. , Sappenfield E. L. 
Published: January 2013

AbstractThe indexed X-ray diffraction powder data of trans-bis(dimethylphenylphosphine)bis(pyrazole)platinum, {Pt(C3H4N2)2[P(CH3)2(C6H5)]2, PTPP} and trans-(tricyclohexylphosphino) (triethylphosphino) platinum(II) chloride, (PtCl2P2C24H48, PTHE) are reported. PTPP crystallizes in the monoclinic space group C2/c and PTHE crystallizes in the orthorhombic space group Pcab. The refined cell parameters were determined by employing a Siemens Debye-Scherrer camera (Fe radiation, λmean = 1.93736 Å). The cell constants are a = 21.516(5), b = 6.287(1), c = 17.929(4)Å, β = 102.51(1)°, V = 2367.7Å3 Dx=1.70Mg m−3, Dm = 1.70Mg m−3 for PTPP and a = 12.271(1), b = 19.375(1), c = 23.864(3)Å, V = 5673.4Å3, Dx = 1.553Mg m−3 for PTHE. The quantitative figures of merit (FN) are F23 = 47(0.010,51) [F20 = 60(0.009,35)] for PTPP and F30 = 12(0.008,324) [F20 = 27(0.017,105)] for PTHE. The JCPD S Diffraction File No. for PTPP is 37-1999 and for PTHE is 37-2000.
Quantitative Analysis of Sedimentary Minerals by Powder X-ray Diffraction
Authors: Bayliss Peter 
Published: January 2013

AbstractThe variables of reflection overlap, crystallinity and crystallite size, primary extinction, microabsorption, chemical substitutions, preferred orientation, and analytical procedures affect quantitative analysis by powder X-ray diffraction. The intensity of the strongest reflection (I) of 39 minerals from a typical sedimentary environment divided by the intensity of the strongest reflection (Ic) of corundum, I/Ic, may be used to determine mineral percentages. Because of the numerous variables mentioned above, the I/Icratios used should be taken from multi-mineral specimens that occur either in the same geological formation for quantitative analysis (±7%) or in a similar geological formation for quantitative analysis (±30%).
Acquisition and Analysis of Powder X-Ray Diffraction Data Using CALS Chromatographic Software
Authors: Moynihan Kelly J. , Proulx Richard , Windsor Brian K. 
Published: January 2013

AbstractA conventional semi-automated powder X-ray diffractometer that was previously equipped with a strip chart recorder for data acquisition has been interfaced to an HP 1000 minicomputer via an analog-to-digital converter. Data acquisition and analysis is now accomplished using CALS chromatographic software and two in-house-developed FORTRAN 77 computer programs. This has resulted in significant improvements in experimental repeatability and accuracy, decreased sample turn-around times, and rapid and facile analysis, manipulation, and comparison of crystallographic data.
Searching and Matching of X-Ray Powder Diffraction Patterns Using a Programmable Calculator
Authors: Škrobian Milan , Havlik Tomas , Havlik Milan 
Published: January 2013

AbstractA simple, practical search/match program, RIFRAN 85, has been written and implemented for the EMG 666B programmable calculator. The computer programs are written in EMG Assembler, which is identical to the assembler language for the Hewlett-Packard 9821 calculator. The EMG 666B is made in Hungary and has 8 kbytes of operational memory. The programs interactively provide qualitative phase analysis of X-ray powder diffraction patterns using standard files collected from published data and stored on a compact magnetic tape cassette. Each standard pattern can comprise up to 35 two-theta — intensity pairs. The identification procedure is based on the comparison of the diffraction data of the standard and of the unknown within limits imposed by user-established match and chemical criteria. This paper describes the algorithm used and the performance of the RIFRAN 85 identification system. The system's operation is illustrated using an example of phase analysis of a mineral sample.
X-Ray Quantitative Analysis of Coal By The Reference Intensity Method
Authors: Davis Briant L. , Johnson L. Ronald , Mebrahtu T. 
Published: January 2013

AbstractTwenty-four coal samples representing the four major rank types were analyzed by the X-ray RIM methodology which includes mass absorption analysis by X-ray transmission and quantitative X-ray powder diffraction. Twenty-three separate mineral species were observed in the samples, many of which could be quantified in the whole coal analysis. Several mineral species at levels of 5 weightpercent or less were observed only in the ashed scans. Some dehydration and reconstitution reactions were observed in the ashing process, including the combination of organically bound alkaline-earth elements and sulfur to form bassanite and magnesium sulfates. Quartz and kaolinite dominated the silicate mineral portion of the mineralogy, whereas calcite and siderite represented the carbonate; pyrite with associated sulfate oxidation products were generally present as well. The X-ray transmission studies were successful in estimating the carbonaceous matter in the whole coal samples and comparison of the chemical oxides derived from the X-ray data with direct analyses from the Penn State data sheets revealed good correlations, although significant departures occurred for some species and a systematic underestimation of aluminum oxide from the X-ray clay peaks was observed. This study suggests that the RIM procedure can be applied to coal mineral and amorphous component analysis on a routine basis.
New Copper (II) — Rare Earth (III) Compounds II. Crystal Chemistry of CuLn2Ge2O8, CuLn2Si4O12 and CuLn2Ge4O12
Authors: Lambert U. , Eysel W. 
Published: January 2013

AbstractTwenty seven new rare earth (Ln) compounds CuLn2 Ge2O8, CuLn2Ge4O12 and CuLn2Si4O12 have been synthesized. The powder diagrams were indexed and solid solutions of silicates and germanates were investigated. Structural variations with temperature, lanthanide contraction and Ge/Si substitution are described. Indications for second order phase transitions were found.
Standard X-Ray Diffraction Powder Patterns from The JCPDS Research Associateship
Authors: McMurdie Howard F. , Morris Marlene C. , Evans Eloise H. , Paretzkin Boris , Wong-Ng Winnie , Hubbard Camden R. 
Published: January 2013

The following new or updated patterns are submitted by the JCPDS Research Associateship at the National Bureau of Standards. The patterns are a continuation of the series of standard X-ray diffraction powder patterns published previously in the NBS Circular 539, the NBS Monograph 25, and in this journal. The methods of producing these reference patterns are described in this journal, Vol. 1, No. 1, p. 40 (1986).The data for each phase apply to the specific sample described. A sample was mixed with one or two internal standards: silicon (SRM640a), silver, tungsten, or fluorophlogopite (SRM675). Expected 2-theta values for these standards are specified in the methods described (ibid.). Data, from which the reported 2-theta values were determined, were measured with a computer controlled diffractometer. Computer programs were used to locate peak positions and calibrate the patterns as well as to perform variable indexing and least squares cell refinement.
Considerations in the Design of Goniometers for Use in X-Ray Powder Diffractometers
Authors: Jenkins R. , Schreiner W. N. 
Published: January 2013

AbstractMost modern X-ray powder diffraction work is carried out using the parafocusing powder diffractometer. The typical instrument employs a mechanical goniometer to control the basic geometric movements required for recording diffraction data. Modern trends toward high speed data acquisition and computerized analytical procedures make the need for a well designed and well maintained goniometer system increasingly critical. This paper reviews the mechanical design parameters of typical goniometer systems in light of their influence on the accuracy and precision obtainable in diffraction data. Data on typical vertical and horizontal goniometer systems are compared, along with bench tests using a state of the art “anti-backlash” gearing system. By examining the nature of the errors typically encountered in today's goniometers it becomes evident why the next major improvement will likely be in software rather than hardware.
The Application of X-Ray Powder Diffraction to Forensic Science
Authors: Thatcher P. J. , Briner G. P. 
Published: January 2013

Although forensic science is regarded with a certain amount of fascination and admiration by the general public, to the practising forensic scientist it is often associated with painstaking and frustrating examinations.This is particularly so in the most traditional area of forensic science, namely that of contact evidence where the identification and comparison of minute samples may provide an important clue for the investigator and assist in the conviction or exoneration of an accused person.Contact evidence may include hairs and other fibres, paint samples, glass fragments, stains, soils and other deposits. Modern instrumentation such as infra-red spectrophotometry, gas chromatography, atomic absorption spectroscopy and energy dispersive X-ray analysis now allows a relatively simple identification of the composition of these materials. However, these techniques are not necessarily directed towards the absolute determination of structure of materials and this is particularly so in the case of crystalline materials of forensic interest such as soil, mortar, brick dust and paint fillers. Although the techniques previously mentioned provide the basis of an elemental analysis this may not be of much assistance in a forensic approach where chemical structure is the basis of a scentific comparison.
X-Ray Diffractometry of Low-Mass Samples
Authors: Zevin L. S. , Zevin I. M. 
Published: January 2013

AbstractThe intensity diffracted by a low-mass sample with negligible absorption may be expressed as It = I∞ (B/2μ*)/G, where I∞ = intensity diffracted by a bulk sample, B = cross section of the primary beam, μ* = mass absorption coefficient, and G = mass of the sample. Measurable intensity may be obtained from samples with less than 1 μg mass. In order to improve the limit of detection, the primary beam should be collimated so as to irradiate the sample and only a minimum volume of the sample support. The optimum spreading area of a low-mass sample is S sinθ≅10μ*. Comminution of low-mass samples to 1 — 2μm particles is adequate for reasonable intensity measurements.
Quantitative Phase Analysis By Linear Regression of Chemistry on X-Ray Diffraction Intensity
Authors: Renault Jacques 
Published: January 2013

AbstractXRF and XRD measurements made on a single pressed powder briquet can be combined to give more quantitative information than either technique employed alone. Speed of analysis and simplification of sample preparation are also enhanced. The algorithm presented here uses multiple linear regression of the concentrations of one or more elements on the corrected X-ray diffraction intensities of the phases containing them. The data reduction program runs on a microcomputer. Data are presented to show its application to mineralogical analysis of artificial mixtures of quartz, microcline (a feldspar) and calcite.
X-Ray Powder Structural Analysis of the Complexes of Benzo-15-Crown-5 with NaClO4 and KI: [C14H20O5]NaClO4 and [C14H20O5]2KI
Authors: Shoham G. , Cohen N. , Schneider S. , Mayer I. 
Published: January 2013

AbstractX-ray powder diffraction analysis of the complex of Benzo-15-Crown-5 (B-15-Crown-5) with NaClO4 displays a monoclinic crystal system with refined unit cell parameters of a = 8.829(3)Å, b = 8.327(3)Å, c = 24.21(2)Å, ß = 99.18(1)Å, V = 1757.1(1)Å3, Z = 4, and Dx = 1.48 g/cm3. The space group, P21/c, and the unit cell dimensions, determined by a single crystal diffraction analysis, agree well with those of the powder analysis. X-ray powder diffraction analysis of the complex of B-15-Crown-5 with KI displays a tetragonal crystal system with refined unit cell dimensions of a = b = 17.869(3)Å, c = 9.761(3)Å, V = 3116.7(1)Å3, Z = 4, and Dx = 1.50 g/cm3. The space group, P4/n, and the unit cell dimensions, determined by a single crystal diffraction analysis, agree well with those of die powder diffraction analysis. The powder and single crystal analyses of the two complexes indicate that in the solid phase, B-15-Crown-5 forms a 1:1 complex with Na+ and a 2:1 complex with K+. The variation in the complexation mode of B-15-Crown-5 with different cations, partially explains the lack of selectivity of this crown ether towards Na+, while from considerations of the cavity size alone this crown ether was expected to be considerably selective towards this cation.
Standard X-Ray Diffraction Powder Patterns of Fifteen Ceramic Phases
Authors: Wong-Ng Winnie , McMurdie Howard F. , Paretzkin Boris , Hubbard Camden R. , Dragoo Alan L. , Stewart James M. 
Published: January 2013

The following fifteen reference patterns of boride, silicide and oxide ceramics represent the first group of ceramic phases measured at the National Bureau of Standards under the project “High Quality Reference Patterns and Total Digital Powder Patterns of Technologically Important Ceramic Phases”. The support and interest of the JCPDS-ICDD in this project is gratefully acknowledged.The general methods of producing these X-ray powder diffraction reference patterns are described in this journal, Vol. 1, No. 1, pg. 40(1986).
Powder X-Ray Data for Synthetic Anhydrous Sodium Zirconium Silicates
Authors: Wilson G. , Glasser F. P. 
Published: January 2013

AbstractA systematic survey of phase formation in the Na2O-ZrO2-SiO2 system has revealed inconsistencies in the number and identity of ternary phases, and of their X-ray powder data. The phases Na2ZrSiO5, Na4Zr2Si3O12, Na2ZrSi2O7 and Na2ZrSi4O11 were prepared by solid-state reaction and their experimental X-ray diffraction patterns measured. Calculated X-ray diffraction patterns were generated by computer, using published crystallographic data, and critically compared with the experimentally observed values. The unit-cell constants were redefined to a greater accuracy than the presently accepted values published in the Powder Diffraction File. Only Na4Zr2Si3O12 produced an X-ray diffraction pattern which agreed with that previously published; those from the other phases were significantly different in both the intensities and positions of the reflections. Data for synthetic Na2ZrSi4O11 identical to the mineral vlasovite are reported.
X-Ray Powder Diffraction and Single-Crystal Data for the Isomorphous Series (Fe,Al)3(K,NH4, H3O)H14(PO4)8 ·4H2O
Authors: Waerstad Kjell R. , Frazier A. William 
Published: January 2013

AbstractX-ray powder diffraction and single-crystal data are reported for a series of isomorphous compounds with the general chemical composition (Fe,Al)3(K,NH4,H3O)H14 (PO4)8·4H2O. The compounds are monoclinic with space group C2/c. Unit-cell parameters were determined on the mixed salt (Fe0.84,Al0.16)3KH14(PO4)8·4H2O, as obtained from sludge precipitated in commercial shipping-grade wet-process phosphoric acid. Single-crystal studies and refined powder diffraction data provided unit-cell parameters of a= 16.908(9) Å, b = 9.588(2) Å, c = 17.539(5) Å, and β = 91.06(4)°.
Determination of Mica Cell Parameters by X-Ray Powder Diffractometry — A Case Study
Authors: Stern W. B. 
Published: January 2013

AbstractPossibilities and restrictions of least-square methods for mica cell refinement are briefly described. If diffractometric raw data are precise and accurate, and if geometrical errors are properly corrected, a cell refinement (determination of ao, bo, cO, β) can be carried out rapidly, but the reliability of obtained data has to be evaluated carefully.
Application of the Rietveld Refinement Procedure in Assaying Powdered Mixtures
Authors: O'Connor Brian H. , Raven Mark D. 
Published: January 2013

AbstractResults are given of an assessment of a Rietveld-type X-ray powder diffraction pattern fitting structure refinement technique for assaying powdered mixtures as an alternative to conventional discrete peak empirical methods of the type described by Klug and Alexander (1974) and Chung (1974). The values obtained for a mixture of corundum and α-quartz, following calibration of the instrument with a profile of the former, indicate that this technique has excellent potential as an analytical tool.
Bragg-Brentano and Seeman-Bohlin Diffractometers for Thin Films
Authors: Zevin L. S. 
Published: January 2013

AbstractThe performances of Seeman-Bohlin (S-B) and Bragg-Brentano (B-B) diffractometers with flat thin film samples were compared on the basis of equal instrumental aberrations. It was found that the S-B arrangement has only a marginal advantage as regards diffracted intensity, and that both types of diffractometer may be successfully employed for characterization of thin films. Diffraction data obtained with very thin metallic films (down to 30 Å) are included for illustration. In order to eliminate reflections from the singlecrystal substrate in the B-B diffractometer, sample tilting was employed. Provided the tilting angle remains within 0.5°, sample tilting causes only moderate additional broadening of the thin film peaks.