Spectroscopic techniques applied to discriminate soils for forensic purposes

Soil Research ◽  
2020 ◽  
Vol 58 (2) ◽  
pp. 151 ◽  
Author(s):  
Luis Valério Prandel ◽  
Vander Freitas Melo ◽  
Samara Alves Testoni ◽  
André Maurício Brinatti ◽  
Sérgio da Costa Saab ◽  
...  

Soils are a complex mixture with a variety of mineralogical, chemical, biological and physical properties, which can be explored within forensic case work. This study aimed to apply energy-dispersive X-ray fluorescence (EDXRF) and Fourier transform infrared (FTIR) spectroscopic techniques to discriminate soil samples collected in southern Brazil in a forensic context. Four replicates of soil were collected at four sites: two sites from the same parent material (claystone) and two other sites from limestone and granite/gneiss respectively. The physical and chemical (organic and mineral composition) and spectroscopic techniques (EDXRF and FTIR) produced 16 quantitative variables from only 2 g of sample. The main results from a forensic context were the separation of the soils collected from close neighbourhoods developed on the same parent material and the separation of soils collected in the A and B horizons of the same soil profile. The highest degree of similarity in the clustering of samples collected at the same site was 98.6% (B horizon in claystone domain). In addition to the parent material, the effect of organic matter on the chemical and mineralogical characteristics of the A horizon was important in the grouping dynamics of samples. This work demonstrated the potential of spectroscopic techniques in a forensic context.

Agropedology ◽  
2019 ◽  
Vol 30 (2) ◽  
Author(s):  
R. Srinivasan ◽  
◽  
R. Vasundhara ◽  
M. Lalitha ◽  
B. Kalaiselvi ◽  
...  

Four typical pedons representing major mango growing soils, developed from granite gneiss parent material were studied for their morphological, physical and chemical properties. The soils were moderately shallow (50-75 cm) to very deep (>150 cm) in depth, loamy sand to sandy clay loam in texture, sub-angular blocky in structure, reddish brown to dark red in colour, slightly acidic to moderately alkaline in reaction, non-saline, very low to high in organic carbon content (0.09 to 1.29%), low AWC (3.36 to 7.80%), low to medium in cation exchange capacity (2.90 to 19.36 cmol (p+) kg-1) and high base saturation (78 to 98%). The soils also had high amounts of coarse fragments in P1 and P2 and high clay content in P4 and P2. Among the exchangeable cations, calcium was found to be high in most of the soils, followed by magnesium, sodium, and potassium. Based on the soil characteristics, the mango growing soils were classified as Typic Haplargids and Typic Paleargids in subgroup level. Varying soil and site characters i.e., poor rainfall, shallow soil depths, excess gravel contents, low AWC, poor nutrient status and severe soil erosion are limiting the growth and development of mango plantation. Developing site-specific soils based suitable management practices can improve the productivity of mango crops.


MRS Bulletin ◽  
1992 ◽  
Vol 17 (5) ◽  
pp. 53-59 ◽  
Author(s):  
Frank C. Hawthorne

Glasses are a minor fraction of Earth materials. However, all igneous processes within the Earth involve a melt phase (magma), and our understanding of the physical and chemical features of these processes is contingent upon an adequate understanding of the melt phase itself. In particular, we wish to relate the behavior of such melts to their composition and structure in the range of physical and chemical conditions in which they occur. The physical conditions of many of these processes are particularly difficult to reproduce in the laboratory, and the ability to predict behavior under such conditions is the goal. From a geological viewpoint, the primary interest is in silicate melts because of the composition of the Earth's lithosphere and mantle. There are significant experimental difficulties in looking at the behavior of silicate melts, so much work has focused on glasses as melt analogues since spectroscopic data on silicate glasses and melts (Figure 1) are similar.Silicate glasses are also of considerable industrial interest, and early work in the geological field borrowed heavily from materials science. However, the thrust to understand natural magmas led geologically based work into more complex chemical systems (e.g., hydrous alkali-alkaline-earth-aluminosilicates) and their behavior at high pressures.The structure of glasses is a complex issue, and many different experimental techniques are needed to resolve the details of their structure. Here I will focus on the following techniques: IR (infrared), Raman, Mössbauer, EXAFS (extended x-ray absorption fine structure) and XANES (x-ray absorption near-edge spectroscopy) spectroscopies.


Author(s):  
C. Goessens ◽  
D. Schryvers ◽  
J. Van Landuyt ◽  
A. Verbeeck ◽  
R. De Keyzer

Silver halide grains (AgX, X=Cl,Br,I) are commonly recognized as important entities in photographic applications. Depending on the preparation specifications one can grow cubic, octahedral, tabular a.o. morphologies, each with its own physical and chemical characteristics. In the present study crystallographic defects introduced by the mixing of 5-20% iodide in a growing AgBr tabular grain are investigated. X-ray diffractometry reveals the existence of a homogeneous Ag(Br1-xIx) region, expected to be formed around the AgBr kernel. In fig. 1 a two-beam BF image, taken at T≈100 K to diminish radiation damage, of a triangular tabular grain is presented, clearly showing defect contrast fringes along four of the six directions; the remaining two sides show similar contrast under relevant diffraction conditions. The width of the central defect free region corresponds with the pure AgBr kernel grown before the mixing with I. The thickness of a given grain lies between 0.15 and 0.3 μm: as indicated in fig. 2 triangular (resp. hexagonal) grains exhibit an uneven (resp. even) number of twin interfaces (i.e., between + and - twin variants) parallel with the (111) surfaces. The thickness of the grains and the existence of the twin variants was confirmed from CTEM images of perpendicular cuts.


2020 ◽  
Vol 71 (1) ◽  
pp. 192-200
Author(s):  
Anca-Luiza Stanila ◽  
Catalin Cristian Simota ◽  
Mihail Dumitru

Highlighting the sandy soil of Oltenia Plain calls for a better knowledge of their variability their correlation with major natural factors from each physical geography. Pedogenetic processes specific sandy soils are strongly influenced by nature parent material. This leads, on the one hand, climate aridity of the soil due to strong heating and accumulation of small water reserves, consequences emphasizing the moisture deficit in the development of the vegetation and favoring weak deflation, and on the other hand, an increase in mineralization organic matter. Relief under wind characteristic sandy land, soil formation and distribution has some particularly of flat land with the land formed on the loess. The dune ridges are less evolved soils, profile underdeveloped and poorly supplied with nutrients compared to those on the slopes of the dunes and the interdune, whose physical and chemical properties are more favorable to plant growth.Both Romanati Plain and the Blahnita (Mehedinti) Plain and Bailesti Plain, sand wind shaped covering a finer material, loamy sand and even loess (containing up to 26% clay), also rippled with negative effects in terms of overall drainage. Depending on the pedogenetic physical and geographical factors that have contributed to soil cover, in the researched were identified following classes of soils: protisols, cernisols, cambisols, luvisols, hidrisols and antrosols.Obtaining appropriate agricultural production requires some land improvement works (especially fitting for irrigation) and agropedoameliorative works. Particular attention should be paid to preventing and combating wind erosion.


2018 ◽  
Vol 21 (7) ◽  
pp. 495-500 ◽  
Author(s):  
Hassan A. Almarshad ◽  
Sayed M. Badawy ◽  
Abdalkarem F. Alsharari

Aim and Objective: Formation of the gallbladder stones is a common disease and a major health problem. The present study aimed to identify the structures of the most common types of gallbladder stones using X-ray spectroscopic techniques, which provide information about the process of stone formation. Material and Method: Phase and elemental compositions of pure cholesterol and mixed gallstones removed from gallbladders of patients were studied using energy-dispersive X-ray spectroscopy combined with scanning electron microscopy analysis and X-ray diffraction. Results: The crystal structures of gallstones which coincide with standard patterns were confirmed by X-ray diffraction. Plate-like cholesterol crystals with laminar shaped and thin layered structures were clearly observed for gallstone of pure cholesterol by scanning electron microscopy; it also revealed different morphologies from mixed cholesterol stones. Elemental analysis of pure cholesterol and mixed gallstones using energy-dispersive X-ray spectroscopy confirmed the different formation processes of the different types of gallstones. Conclusion: The method of fast and reliable X-ray spectroscopic techniques has numerous advantages over the traditional chemical analysis and other analytical techniques. The results also revealed that the X-ray spectroscopy technique is a promising technique that can aid in understanding the pathogenesis of gallstone disease.


1999 ◽  
Vol 23 (7) ◽  
pp. 418-419
Author(s):  
Simon J. Coles ◽  
Paul Faulds ◽  
Michael B. Hursthouse ◽  
David G. Kelly ◽  
Georgia C. Ranger ◽  
...  

Nickel(II) phosphine complexes are prepared with a series of diphenylalkenylphosphine ligands and characterised by single crystal X-ray diffraction and spectroscopic techniques.


2021 ◽  
pp. 174751982198965
Author(s):  
Guoqi Zhang

( E)-4-[2-(Pyridin-4-yl)vinyl]benzaldehyde, containing both a 4-vinylpyridine and an aldehyde functionality, is utilized to develop new, highly conjugated chalcone compounds and a bis-Schiff base azine compound. The chalcone-containing compounds are further explored for their protonation, methylation and silver(I) coordination chemistry using the pyridine moiety. In parallel, a cyano-containing analogue, ( E)-4-[2-(pyridin-4-yl)vinyl]benzonitrile is also synthesized and studied for its silver(I) coordination chemistry. These new compounds are fully characterized by mass spectrometry, elemental analysis and spectroscopic techniques. The methylated product of ( E)-1-(9-anthryl)-3-{4-[2-(pyridin-4-yl)vinyl]phenyl}prop-2-en-1-one and a silver complex of ( E)-4-[2-(pyridin-4-yl)vinyl]benzonitrile are structurally determined by X-ray crystallography.


2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Hiroyuki Yamane ◽  
Masaki Oura ◽  
Osamu Takahashi ◽  
Tomoko Ishihara ◽  
Noriko Yamazaki ◽  
...  

AbstractAdhesion is an interfacial phenomenon that is critical for assembling carbon structural composites for next-generation aircraft and automobiles. However, there is limited understanding of adhesion on the molecular level because of the difficulty in revealing the individual bonding factors. Here, using soft X-ray spectromicroscopy we show the physical and chemical states of an adhesive interface composed of a thermosetting polymer of 4,4’-diaminodiphenylsulfone-cured bisphenol A diglycidyl ether adhered to a thermoplastic polymer of plasma-treated polyetheretherketone. We observe multiscale phenomena in the adhesion mechanisms, including sub-mm complex interface structure, sub-μm distribution of the functional groups, and molecular-level covalent-bond formation. These results provide a benchmark for further research to examine how physical and chemical states correlate with adhesion, and demonstrate that soft X-ray imaging is a promising approach for visualizing the physical and chemical states at adhesive interfaces from the sub-mm level to the molecular level.


Author(s):  
Romain Geneaux ◽  
Hugo J. B. Marroux ◽  
Alexander Guggenmos ◽  
Daniel M. Neumark ◽  
Stephen R. Leone

Attosecond science opened the door to observing nuclear and electronic dynamics in real time and has begun to expand beyond its traditional grounds. Among several spectroscopic techniques, X-ray transient absorption spectroscopy has become key in understanding matter on ultrafast time scales. In this review, we illustrate the capabilities of this unique tool through a number of iconic experiments. We outline how coherent broadband X-ray radiation, emitted in high-harmonic generation, can be used to follow dynamics in increasingly complex systems. Experiments performed in both molecules and solids are discussed at length, on time scales ranging from attoseconds to picoseconds, and in perturbative or strong-field excitation regimes. This article is part of the theme issue ‘Measurement of ultrafast electronic and structural dynamics with X-rays’.


1970 ◽  
Vol 37 (290) ◽  
pp. 705-707 ◽  
Author(s):  
L. C. Hodge

SummaryRussellite Bi2O3. WO3 occurs in a small pegmatite near Poona, Western Australia. The fine-grained yellow to pale green material is an inseparable mixture of russellite, bismite, koechlinite, and bismutite. X-ray powder diffraction, physical, and chemical data agree in general with the original description of the mineral from Cornwall, England. The original analyses made on micro quantities are now supplemented by analyses on macro quantities.


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