Fundamental Parameters Line Profile Fitting in Laboratory Diffractometers.

The fundamental parameters approach to line profile fitting uses physically based models to generate the line profile shapes. Fundamental parameters profile fitting (FPPF) has been used to synthesize and fit data from both parallel beam and divergent beam diffractometers. The refined parameters are determined by the diffractometer configuration. In a divergent beam diffractometer these include the angular aperture of the divergence slit, the width and axial length of the receiving slit, the angular apertures of the axial Soller slits, the length and projected width of the x-ray source, the absorption coefficient and axial length of the sample. In a parallel beam system the principal parameters are the angular aperture of the equatorial analyser/Soller slits and the angular apertures of the axial Soller slits. The presence of a monochromator in the beam path is normally accommodated by modifying the wavelength spectrum and/or by changing one or more of the axial divergence parameters. Flat analyzer crystals have been incorporated into FPPF as a Lorentzian shaped angular acceptance function. One of the intrinsic benefits of the fundamental parameters approach is its adaptability any laboratory diffractometer. Good fits can normally be obtained over the whole 20 range without refinement using the known properties of the diffractometer, such as the slit sizes and diffractometer radius, and emission profile

Microscopic co-existence of superconductivity and magnetism in Ba1-xKxFe2As2

It is widely believed that, in contrast to its electron doped counterparts, the hole doped compound Ba1-xKxFe2As2 exhibits a mesoscopic phase separation of magnetism and superconductivity in the underdoped region of the phase diagram. Here, we report a combined high-resolution x-ray powder diffraction and volume sensitive muon spin rotation study of underdoped Ba1-xKxFe2As2 (0 \leq x \leq 0.25) showing that this paradigm is wrong. Instead we find a microscopic coexistence of the two forms of order. A competition of magnetism and superconductivity is evident from a significant reduction of the magnetic moment and a concomitant decrease of the magneto-elastically coupled orthorhombic lattice distortion below the superconducting phase transition.Comment: 4 pages, 4 figure

A waste-derived lithium metasilicate basic catalyst

A mixed product of lithium metasilicate (74%) and minor proportions of calcium carbonate, lithium carbonate and calcium hydroxide was prepared by hydrothermal synthesis from waste green container glass in 4 M lithium hydroxide solution at 125 °C. The reaction product was characterised by powder X-ray diffraction and Fourier transform infrared spectroscopy. The lithium metasilicate product was found to be a successful heterogeneous catalyst for the Knoevenagel synthesis of ethyl trans-α-cyanocinnamate from benzaldehyde and ethyl cyanoacetate

STRUKTUR TEKS DAN MAKNA PEMENTASAN KESENIAN TRADISIONAL DEDER KALIMANTAN TENGAH (THE STRUCTURE OF TEXT AND MEANING OF DEDER TRADITIONAL ART PERFORMANCE IN CENTRAL KALIMANTAN)

Struktur Teks dan Makna Pementasan Kesenian Tradisional Deder Kalimantan Tengah.Deder adalah syair yang dilantunkan serta berisikan nasehat, sindiran, atau petuah yang dapatdiiringi oleh nyanyian. Deder dilakukan berpasangan, laki-laki dan perempuan secara bergantian.Saat penampilannya, deder diiringi oleh alat musik kecapi, gong, suling, dan gendang. Penelitianini menggunakan pendekatan kualitatif. Dengan pendekatan ini, peneliti dapat memberikan tujuanpenelitian secara objektif karena menggunakan dokumen karya sastra, yaitu kesenian deder yangditampilkan oleh pededer yang selanjutnya ditranskripsikan menjadi bentuk tulis untuk diteliti. Sumberdata diperoleh dari beberapa orang yang latar belakangnya adalah sebagai seniman sastra lisan dederdan juga rekaman video penampilan deder. Hasil penelitian yang diperoleh adalah sebagai berikut. (1)Struktur teks deder terdiri atas pembukaan, isi, danpenutup. Pembukaan berisi tentang pengucapansalam kepada hadirin dan kepada seluruh pihak. Penyampaian isi berisi tentang penyampaian maksuddan tujuan dari bededer. Penutup berisi salam perpisahan kepada hadirin dan kepada seluruh pihak.(2). Teks deder pada umumnya, seperti deder Dampak Sosial Asep memiliki rima berangkai namunada beberapa bait yang tidak sempurna. Terjadi pengecualian pada deder karya Bilton yaitu tidaksemua baitnya memiliki rima karena hamper tiap baitnya, terdapat pengulangan bunyi akhir katalarik pertama dengan kata awal larik kedua. Hal tersebut terjadi karena pemenggalan kata akhir larikpertama yang kemudian disebutkan secara utuh pada kata awal larik kedua. Selain itu teks dedermemiliki asonansi atau pengulangan bunyi huruf vocal dan aliterasi atau pengulangan bunyi hurufkonsonan. (3).Pola irama teks deder dalam pelantunannya terdapat penekanan pada beberapa katatiap baitnya. Letak penekanannya tidak teratur tergantung kesesuain kata dengan nada yang ingindilantunkan. Teks Deder terdiri atas kata yang tidak sama jumlahnya pada tiap baitnya.4.Penyajiandeder ditampilkan dengan menghadirkan unsure penyaji, penonton, music setting, dan interaksi denganpenonton. Penyaji pada deder ditampilkan dengan berpasangan, biasanya laki-laki dengan perempuan.Pededer secara bergantian melantunkan teks deder antara bait satu ke bait selanjutnya hingga selesai.Penonton yang menyaksikan berasal dari berbagai kalangan. Alat musik yang digunakan dalampenyajian deder adalah gong,gendang, kecapi dan suling yang merupakan khas Kalimantan tengah.Pada deder karya Bilton, Setting yang ditampilkan adalah taman wisata kum-kum dan juga tempatwisata huma betang. Kum-kum menggambarkan panorama hutan di Kalimantan sedangkan wisataHuma betang menggambarkan rumah yang digunakan suku dayak pada zaman dulu. Sedangkan, padadeder dampak sosial asep, setting bertempat di studio RRI KalimantanTengah.Kata-kata kunci: deder, struktur teks, pementasa

The rapid size- and shape-controlled continuous hydrothermal synthesis of metal sulphide nanomaterials

Continuous flow hydrothermal synthesis offers a cheap, green and highly scalable route for the preparation of inorganic nanomaterials which has predominantly been applied to metal oxide based materials. In this work we report the first continuous flow hydrothermal synthesis of metal sulphide nanomaterials. A wide range of binary metal sulphides, ZnS, CdS, PbS, CuS, Fe₍₁₋ᵪ₎S and Bi₂S₃, have been synthesised. By varying the reaction conditions two different mechanisms may be invoked; a growth dominated route which permits the formation of nanostructured sulphide materials, and a nucleation driven process which produces nanoparticles with temperature dependent size control. This offers a new and industrially viable route to a wide range of metal sulphide nanoparticles with facile size and shape control

Polymorphism in sulfadimidine/4- aminosalicylic acid cocrystals: solid-state characterization and physicochemical properties

YesPolymorphism of crystalline drugs is a common phenomenon. However, the number of reported polymorphic cocrystals is very limited. In this work, the synthesis and solid state characterisation of a polymorphic cocrystal composed of sulfadimidine (SD) and 4- aminosalicylic acid (4-ASA) is reported for the first time. By liquid-assisted milling, the SD:4-ASA 1:1 form I cocrystal, the structure of which has been previously reported, was formed. By spray drying, a new polymorphic form (form II) of the SD:4-ASA 1:1 cocrystal was discovered which could also be obtained by solvent evaporation from ethanol and acetone. Structure determination of the form II cocrystal was calculated using high resolution X-ray powder diffraction. The solubility of the SD:4-ASA 1:1 cocrystal was dependent on the pH and predicted by a model established for a two amphoteric component cocrystal. The form I cocrystal was found to be thermodynamically more stable in aqueous solution than form II, which showed transformation to form I. Dissolution studies revealed that the dissolution rate of SD from both cocrystals was enhanced when compared to a physical equimolar mixture and pure SD.Science Foundation Ireland (SFI) under Grant Number 07/SRC/B1158 and SFI/12/RC/2275

Suspension high velocity oxy-fuel spraying of TiO2: a quantitative approach to phase composition

A range of coatings from a water based suspension of anatase has been prepared by suspension high velocity oxy-fuel spraying with the aim to study effects of heat power of the flame on phase composition, microstructure and surface topography. Three most commonly used approaches of quantitative phase analysis have been scrutinized with respect to their applicability and as some of the coatings showed presence of preferred orientation and it was argued that quantitative Rietveld refinement is the most accurate method for phase composition determination. Coatings had a layered duplex anatase/rutile microstructure with fraction of rutile increasing exponentially with heat power. Spraying at the lower heat power led to a lower surface roughness and higher power resulted in surfaces with pronounced humps, which were distributed homogeneously on the surface. The emergence of humps is related to an increase in macroscopic surface area of up to 30% with respect to the flat coating

Whole-pattern profile fitting of powder diffraction data collected in parallel-beam flat-plate asymmetric reflection geometry

Abstract: A simple, physically based model that allows the whole-pattern profile fitting of diffraction data collected in parallel-beam flat-plate asymmetric reflection geometry is presented. In this arrangement, there is a fixed angle between the incident beam and the sample, resulting in a fixed-length beam footprint. The use of a wide-angle detector for the simultaneous detection of the data precludes the use of any diffracted beam optics. Therefore, the observed peak widths are a function of the length of the beam footprint on the sample. The model uses up to three refinable parameters, depending on the intensity profile of the beam, to calculate the effect of diffraction angle on the width of all diffracted peaks. The use of this model reduces the total number of parameters required to fit the observed peak widths and shapes, hence leading to increased stability in the profile analysis. Implementations of the model are provided for both fundamental parameters and empirical approaches