scholarly journals Investigations into Sampling Approaches for Chemical Analysis of Latent Fingermark Residue

2019 ◽  
Author(s):  
Buddhika Dorakumbura ◽  
Francesco Busetti ◽  
Simon Lewis
Keyword(s):  
Chemical Composition ◽  
Chemical Analysis ◽  
Sampling Strategies ◽  
Deposition Pressure ◽  
Polar Material ◽  
Percentage Difference ◽  
Porous Surfaces ◽  
Latent Fingermark ◽  
Donor Variation ◽  
Subsequent Chemical

<div> <div> <div> <p>The quantitative variation in latent fingermark deposits sampled from the same donor (intra-donor) poses considerable challenges to studies into the chemical composition of latent fingermarks. The work presented here investigates approaches to the sampling of latent fingermark residues within this context. The amount of squalene in fingermarks deposited on non-porous surfaces, determined by GC-MS, was used as an indicator of the amount of non-polar material present. It was found that the percentage difference of squalene between deposits from two hands at a given time, without controlling the deposition pressure, was in the range of 4-100 %. This was reduced to 0-44 % in alternative sampling approaches where deposition pressure was controlled. These results demonstrate the significant influence of sampling on subsequent chemical analysis of fingermark residues, and offer possible sampling strategies to overcome issues associated with intra-donor variation. </p> </div> </div> </div>

scholarly journals Investigations into Sampling Approaches for Chemical Analysis of Latent Fingermark Residue

2019 ◽  
Author(s):  
Buddhika Dorakumbura ◽  
Francesco Busetti ◽  
Simon Lewis
Keyword(s):  
Chemical Composition ◽  
Chemical Analysis ◽  
Sampling Strategies ◽  
Deposition Pressure ◽  
Polar Material ◽  
Percentage Difference ◽  
Porous Surfaces ◽  
Latent Fingermark ◽  
Donor Variation ◽  
Subsequent Chemical

<div> <div> <div> <p>The quantitative variation in latent fingermark deposits sampled from the same donor (intra-donor) poses considerable challenges to studies into the chemical composition of latent fingermarks. The work presented here investigates approaches to the sampling of latent fingermark residues within this context. The amount of squalene in fingermarks deposited on non-porous surfaces, determined by GC-MS, was used as an indicator of the amount of non-polar material present. It was found that the percentage difference of squalene between deposits from two hands at a given time, without controlling the deposition pressure, was in the range of 4-100 %. This was reduced to 0-44 % in alternative sampling approaches where deposition pressure was controlled. These results demonstrate the significant influence of sampling on subsequent chemical analysis of fingermark residues, and offer possible sampling strategies to overcome issues associated with intra-donor variation. </p> </div> </div> </div>

scholarly journals Investigations into Sampling Approaches for Chemical Analysis of Latent Fingermark Residue

2019 ◽  
Author(s):  
Buddhika Dorakumbura ◽  
Francesco Busetti ◽  
Simon Lewis
Keyword(s):  
Chemical Composition ◽  
Chemical Analysis ◽  
Sampling Strategies ◽  
Deposition Pressure ◽  
Polar Material ◽  
Percentage Difference ◽  
Porous Surfaces ◽  
Latent Fingermark ◽  
Donor Variation ◽  
Subsequent Chemical

<div> <div> <div> <p>The quantitative variation in latent fingermark deposits sampled from the same donor (intra-donor) poses considerable challenges to studies into the chemical composition of latent fingermarks. The work presented here investigates approaches to the sampling of latent fingermark residues within this context. The amount of squalene in fingermarks deposited on non-porous surfaces, determined by GC-MS, was used as an indicator of the amount of non-polar material present. It was found that the percentage difference of squalene between deposits from two hands at a given time, without controlling the deposition pressure, was in the range of 4-100 %. This was reduced to 0-44 % in alternative sampling approaches where deposition pressure was controlled. These results demonstrate the significant influence of sampling on subsequent chemical analysis of fingermark residues, and offer possible sampling strategies to overcome issues associated with intra-donor variation. </p> </div> </div> </div>

scholarly journals Investigations into Sampling Approaches for Chemical Analysis of Latent Fingermark Residue

2019 ◽  
Author(s):  
Buddhika Dorakumbura ◽  
Francesco Busetti ◽  
Simon Lewis
Keyword(s):  
Gas Chromatography Mass Spectrometry ◽  
Compositional Variation ◽  
Sampling Strategies ◽  
Deposition Pressure ◽  
Polar Material ◽  
Percentage Difference ◽  
Porous Surfaces ◽  
Latent Fingermark ◽  
Controlled Deposition ◽  
Donor Variation

Compositional variation of latent fingermark deposits sampled from the same donor (intra-donor) poses considerable challenges for the investigation of the degradation of chemical composition. The work presented here investigates the best approach of sampling of latent fingermark residues within this context. Gas chromatography-mass spectrometry (GC-MS) was used to quantify the amount of squalene in fingermarks deposited on non-porous surfaces and used it as an indicator of the amount of non-polar material successfully extracted. It was found that the percentage difference of squalene between two deposits (from two hands) obtained at a given time without controlling the deposition pressure was in the range of 4-100%. This was reduced to 0-44% in the other three sampling approaches, where deposition pressure was controlled. Under controlled deposition pressure, the averages of percentage difference (n=9) for sebum-rich and natural deposits were 13% and 20% respectively. These results demonstrate the significant influence of fingermark sampling approach over data and offer possible sampling strategies that can be undertaken to overcome issues associated with intra-donor variation.

The chemical composition of leucoxene in Cainozoic bauxite from Boolarra, Victoria

1942 ◽  
Vol 26 (179) ◽  
pp. 273-274 ◽  
Author(s):  
A. B. Edwards
Keyword(s):  
Chemical Composition ◽  
Chemical Analysis ◽  
Olivine Basalt ◽  
Pure Sample ◽  
Residual Structure ◽  
Aluminium Titanate

During a petrological examination of samples of bauxite from Boolarra, in south Gippsland, Victoria, it was noted that some specimens of the bauxite, which is largely derived from Tertiary olivine-basalt, contained numerous grains of yellow-brown to amber-yellow leucoxene. The leucoxene is clearly pseudo-morphous after ilmenite, residual particles of ilmenite being enclosed in many of the leucoxene grains. Most of the leucoxene grains are opaque, but occasional grains are translucent to transparent, though isotropic. Some of them show parallel markings suggestive of cleavage, but probably a residual structure from the replaced ilmenite. In view of the highly aluminous nature of the enclosing rock, there seemed some possibility that this mineral might be the little-known aluminium titanate, xanthitane. It was thought, therefore, that if a pure sample of the mineral could be prepared, a chemical analysis would establish its identity.

scholarly journals Elementary chemical analysis in leaves infected by fumagina by X-Ray fluorescence technique

2007 ◽  
Vol 50 (5) ◽  
pp. 851-860 ◽  
Author(s):  
Maria Sélia Blonski ◽  
Carlos Roberto Appoloni ◽  
Paulo Sérgio Parreira ◽  
Pedro Henrique Arruda Aragão ◽  
Virgilio Franco Nascimento Filho
Keyword(s):  
Chemical Composition ◽  
Chemical Analysis ◽  
Fluorescence Technique ◽  
Energy Dispersion ◽  
X Ray ◽  
Set Up ◽  
Elementary Chemical ◽  
Cu And Zn

Energy Dispersion X-Ray Fluorescence Technique (EDXRF) was employed to study the effects of the fumagina disease on the elementary chemical composition of the leaves. The experimental set up consisted of a Mo X-ray tube (Ksub<FONT FACE=Symbol>µ</FONT> = 17.44 keV) with Zr filter and a Si (Li) detector. The measurements were performed with the infected and healthy leaves of citric plants. The elements Ti, Mn, Fe, Cu and Zn were quantified, with an average DL of 69, 12, 8, 4 and 4 µg.g-1 respectively. The obtained concentration for Fe varied from 44 to 192 µg.g-1 in healthy leaves and from 363 to 704 µg.g-1 in infected leaves with fumagina .

scholarly journals Hot metal desulfurization by marble waste and fluorspar

2012 ◽  
Vol 65 (2) ◽  
pp. 233-240 ◽  
Author(s):  
Felipe Nylo de Aguiar ◽  
Felipe Fardin Grillo ◽  
Jorge Alberto Soares Tenório ◽  
José Roberto de Oliveira
Keyword(s):  
Chemical Composition ◽  
Chemical Analysis ◽  
Pig Iron ◽  
Hot Metal ◽  
Industrial Mixture ◽  
Desulfurization Process ◽  
Hot Metal Desulfurization ◽  
Vacuum Sampling ◽  
Marble Waste

The objective of this paper is to present an analysis of the use of residual marble mixtures in the pig iron desulfurization process. The study involved the use of: marble waste, fluorspar, lime, and hot metal. Four mixtures were made and added to a liquid hot metal - with known chemical composition - at a temperature of 1450ºC. The mass of each element was calculated from its chemical analysis and compared with an industrial mixture. All of the four mixtures used in the experiments were stirred by a mechanical stirrer. Samples were collected by vacuum sampling for times of 5, 10, 15, 20, and 30 minutes, and analysis was performed to check sulfur variation in the bath with time. The results were analyzed and they verified that it was possible to use marble waste as a desulfurizer.

scholarly journals Effect of Nickel Equivalent on Austenite Transition Ratio in Ni-Mn-Cu Cast Iron

2013 ◽  
Vol 13 (2) ◽  
pp. 53-58 ◽  
Author(s):  
A. Janus ◽  
A. Kurzawa
Keyword(s):  
Cast Iron ◽  
Chemical Composition ◽  
Chemical Analysis ◽  
Wall Thickness ◽  
Brinell Hardness ◽  
Austenite Decomposition ◽  
Structural Components ◽  
Microscopy Image ◽  
Image Analyser ◽  
Nickel Equivalent

Abstract Determined was quantitative effect of nickel equivalent value on austenite decomposition degree during cooling-down castings of Ni-Mn- Cu cast iron. Chemical composition of the alloy was 1.8 to 5.0 % C, 1.3 to 3.0 % Si, 3.1 to 7.7 % Ni, 0.4 to 6.3 % Mn, 0.1 to 4.9 % Cu, 0.14 to 0.16 % P and 0.03 to 0.04 % S. Analysed were castings with representative wall thickness 10, 15 and 20 mm. Scope of the examination comprised chemical analysis (including WDS), microscopic observations (optical and scanning microscopy, image analyser), as well as Brinell hardness and HV microhardness measurements of structural components.

scholarly journals Failure Analysis of fractured Fixing Bolts of a Mobile Elevating Work Platform using Finite Element Methods

2019 ◽  
Author(s):  
DongHoon Choi ◽  
Jae-Hoon Kim
Keyword(s):  
Finite Element ◽  
Chemical Composition ◽  
Chemical Analysis ◽  
Failure Analysis ◽  
Visual Inspection ◽  
Standard Procedure ◽  
Fatigue Analysis ◽  
Certification Authority ◽  
Element Analysis ◽  
Safety Certification

Mobile elevating work platforms (MEWPs) consist of a work platform, extending structure, and chassis, and are used to move persons to working positions. MEWPs are useful but are composed of pieces of equipment, and accidents do occur owing to equipment defects. Among these defects, accidents caused by the fracture of bolts fixed to the extension structure and swing system are increasing. This paper presents a failure analysis of the fixing bolts of MEWP. Standard procedure for failure analysis was employed in this investigation. Visual inspection, chemical analysis, tensile strength measurement, and finite element analysis (FEA) were used to analyze the failure of the fixing bolts. Using this failure analysis approach, we found the root cause of failure and proposed a means for solving this type of failure in the future. First, the chemical composition of the fixing bolt is obtained by a spectroscopy chemical analysis method, which determined that the chemical composition matched the required standard. The tensile test showed that the tensile and yield strengths were within the required capacity. The stress analysis was carried out at five different boom angles, and it was determined that the fixing bolt of MEWP can withstand the loads at all the boom angles. The outcomes of the fatigue analysis revealed that the fixing bolt fails before reaching the design requirements. The results of the fatigue analysis showed primarily that the failure of the fixing bolt was due to fatigue. A visual inspection of the fractured section of the fixing bolt also confirmed the fatigue failure. We propose a method to prevent failure of the fixing bolt of the MEWP from four different standpoints: the manufacturer, safety certification authority, safety inspection agency, and owner.

scholarly journals ANALISIS BEBERAPA UNSUR KIMIA KOMPOS Azolla mycrophylla

2018 ◽  
Vol 14 (2) ◽  
pp. 60-5
Author(s):  
Sri Utami Lestari ◽  
Muryanto Muryanto
Keyword(s):  
Chemical Composition ◽  
Chemical Analysis ◽  
Rainy Season ◽  
Nutrient Content ◽  
N Fertilizer ◽  
High Nitrogen ◽  
Leaf Part

The most consumed part of the plants is the leaf part so that the fertilizer provided should contain high nitrogen (N). The nature of the N fertilizer is volatile and when the rainy season there can be washing.  When plants deficienci nutrients shows symtoms of yellowing leaves so that the application of N fertilizer to the plant must remain unfulfilled.  Azolla is a usable alternative.  Azolla has a high N nutrient content because it is symbiotic with anabaena in binding to free nitrogen in the air.             The purpose of this study was to determine the chemical composition (pH,N,P,K) Azolla mycrophylla.  The experiment was conducted experimentally with the first stage of composting azolla after it was done chemical analysis in the laboratory.  The result of this research can be concluded that chemical analysis of Azolla mycrophylla cpmpost is as follows :pH 7,17, N 2,57%, P 0,34%, K 0,03%.  

Sign in / Sign up

Export Citation Format

Share Document