A historical overview of the understanding of art and the path to abstract painting

This paper deals with the analysis of the historical work from the beginning of the ancient era, when painting was considered a craft, until today, where the artist has complete freedom of expression. It is about the time when painting was declared as a spiritual skill and through which stages painting and society itself went through. Many challenges were imposed on artists in order to survive in the coming periods, until they fully freed themselves and started making pure art from the depths of their souls. Pictures that are full of emotions and feelings can only create a pure spirit. Artists resisted the way they were accepted in society, with new rebellious ideas of the time. Starting with modernism and the emergence of abstract painting, and later abstract expressionism. The very position of the most influential artists of those periods in which they lived is analyzed in this paper. Through various applications of their most famous works, how their art contributed to the development of painting and how they inspired other artists to continue to always search for something new

Characterization and potential application of dextran-based biopolymer powder obtained from Hydrangea macrophylla liquid anthocyanins extract by ultrasonic extraction

Biopolymers have numerous advantages, such as their biodegradable, non-toxic, non-inflammatory and biocompatible properties, and, therefore, have a potential for various applications. In this paper dextran-based biopolymer powder, obtained from Hydrangea macrophylla liquid anthocyanins extract by ultrasonic extraction and simple precipitating method, was synthetized and characterized in order to determine its properties and potential application. Attenuated total reflectance Fourier-transform infrared spectroscopy (ATR FT-IR) analyses showed interactions between the components of the system. Optical microscopy suggested that the prepared biopowder formulation was small and somewhat uniform in size, and also showed its easy binding to the fingerprint residues. Additionally, the prepared biopolymer powder was used to visualize latent fingerprints left on different non-porous and semi-porous surfaces, i.e. flat wood, glass, plastic and rubber. The results demonstrated the potential of the obtained dextran-based biopowder to complement routinely applied systems in developing latent fingerprints

The application of chitosan-based micropowders in development of latent fingermarks

Latent fingermarks are common type of traces found at the crime scene. Therefore, their visualization and enhancement are widely used techniques in identification of offenders and accomplices by law enforcement agencies worldwide. Chemical and physical methods seemed to be reliable for that purpose and have now been used for years. Therefore, researchers focus their work in order to discover new methods for detection and visualization of latent fingermarks. In this regard, the usage of polymeric materials, especially biopolymers, has not yet been sufficiently tested, and scientific public is almost unaware of the potential of these materials in forensic science. In this paper, conjugates based on chitosan were obtained by the precipitating method and their application in detection and visualization of latent fingermarks was examined. The results demonstrated that this bio-based powder system could be potentially used as substitutes for commercially used powders in detecting and visualizing of latent fingermarks

Detection and enhancement of latent fingerprints using dextran-based biopolymer powders obtained from anthocyanin solution

Dextran is extensively exploited in medicine and pharmacy, but, currently no studies using this biopolymer as a powder system for enhancement of latent fingerprints were published. In this paper four different formulations of dextran-based biopolymer powders, obtained by simple precipitation of dextran within anthocyanin solution, were synthetized and characterized in order to determine potential of these biopowders in forensic application. Since detrimental effect on humans is often present while routinely employing commercial dusting methods, the main advantage of prepared dextran-based biopowders are their non-toxic properties, contributing to the safer/healthier operating conditions. The interactions between components of the systems were confirmed by FT-IR analysis. Optical microscopy was used to determine the size of the prepared biopowders, while simultaneously confirmed the interaction between powders and the sweat/lipid residues present in the latent trace. The results demonstrated the potential of novel dextran-based biopowders to supplement routinely employed physical systems in visualizing latent fingerprints

Chitosan-based micropowders for the development of latent fingermarks – the effect of biopolymer concentration on powder properties

Detection and enhancement of these marks nowadays is of a huge importance for law enforcement agencies in order to identify persons/offenders. Although commercial chemical and physical methods provide satisfying results on multiple surfaces (glass, wood, rubber surface, etc.), many surfaces still pose a great challenge (firearms, colored surfaces and fabrics, etc.), and not to mention their toxicity and detrimental effect to users. Thus, many research groups focus their efforts in constant improvement and development of already used methods and in preparation of new systems. Due to their specific properties, the polymeric materials, especially biopolymers, are drawing an incredible level of the attention, while experiencing the rapid growth in all areas of research and application. However, the application of these materials in the field of forensic science has not yet been sufficiently exploited and the scientific public is almost unaware of its potential in aforementioned forensic application. In this paper, conjugates based on chitosan were obtained by the precipitating method. The initial concentration of the biopolymer (biopolymer/crosslinker ration) was varied and their potential in detection and visualization of latent fingermarks was examined. The prepared micropowders were characterized by spectrophotometric and spectroscopy methods, while scanning electron microscopy confirmed the shape, size and uniformity of the obtained micropowders, as well as their ability to bind to the fingerprint residues. The results demonstrated that these bio-based micropreparations have potential for commercial development and could complement commercial powders in visualizing and enhancing latent fingermarks

Tehnička dijagnostika i održavanje prema stanju na primeru remonta aviona

U radu je prikazano i objašnjeno održavanje tehničkih sistema, primenom tehničke dijagnostike i održavanja prema stanju, na primeru aviona tipa G-4, korišćenjem programa ubrzanog remonta.This paper presents and elucidates the maintenance of technical systems, using technical diagnostics and condition-based maintenance (CBM), in the case of a G-4 type aircraft, applying an accelerated overhaul programme

Chitosan And Dextran Based Powders – The Preparation, Performance Comparison and Potential Application in Forensic Examination of Latent Fingermarks

The papillary lines are unique for each person, and that feature is frequently used in modern forensic science to identify and distinguish individuals. Fingerprints are often present at the crime scene, but they are usually in the form of latent (invisible) marks which need to be visualized prior to the further processing. Many routinely employed commercial methods show harmful effect on human health, so the research groups are constantly trying to improve or develop some new approaches, and some of them are resorting to the utilization of bio(polymeric) materials. This paper deals with chitosan- and dextran-based biopowders prepared and characterized to evaluate their potential application in visualizing latent fingermarks. Chitosan and dextran are widely used in medicinal and pharmaceutical applications, but there are only a few studies regarding the utilization of these biopolymers as a component for the fingerprint powder. These biopolymeric materials offer many benefits, such as non-toxic properties, specific binding mechanisms, and they also satisfy the cost-benefit demands. Two chitosan-based formulations and one dextran-based formulation were obtained in simple synthesis processes. FT-IR analyses confirmed interactions between components of prepared systems. Optical microscopy showed that prepared powder formulations possess small and uniformly distributed particles, which contributed to their easy binding to the sweat and lipid residues present in the fingerprint trace. Prepared formulations were tested on a rubber (semi-porous) and glass (non-porous) surface. The results indicated that the obtained bio-based powders have the potential to complement commercially exploited physical systems/fingerprint powders in detecting and enhancing latent fingermarks

Development of Latent Fingermarks on Different Substrates Using Polyaniline-Based Powder Obtained by Simple Precipitating Method

Purpose: Polymeric materials are widely used in various industries and fields, such as vehicle and air industry, medicine, pharmacy and nanotechnology, but still insufficiently investigated in forensic applications. Their specific properties could be of a great significance in forensic trace analysis and they could also gratify the cost-benefit requirements. Design/Methods/Approach: This paper deals with polyaniline-based polymer powder, obtained by simple precipitating method, with the aim to develop latent fingermarks deposited onto different surfaces, often found at the crime scene. Findings: Attenuated total reflectance Fourier-transform infrared spectroscopy (ATR FT-IR) analyses confirmed interactions between components of the system. Optical microscopy and scanning electron microscope (SEM) analysis suggested that prepared powder has fine, uniform particles, which easily bind to the sweat and lipid fingerprint residues. Prepared powder was also used to visualize latent fingermarks left on different non-porous, semi-porous and porous surfaces, i.e. plywood, glass and paper. Originality/Value: Obtained results showed that prepared powder could be used as a substitution for commercially employed fingerprint powders used in everyday forensic practice/trace analysis

Visualization of Latent Fingerprints Using Dextran-Based Micropowders Obtained from Anthocyanin Solution

Fingerprints are usually classified as patent, plastic, and/or latent. However, detection and visualization of latent fingerprints, as relevant traces found at the crime scene are very important for reliable identification of suspects by law enforcement personnel. Chemical and physical methods have now been used for years for that purpose, but they showed many deficiencies, where the most important one was related to their toxicity. Therefore, researchers are in constant search for producing complementary, less harmful methods, and some novel approaches are based on (bio)polymeric materials exploiting their specific properties. In this paper, dextran-based micropowders obtained from anthocyanin solution by the simple precipitating method were synthesized and characterized. Dextran is widely used in medicinal and pharmaceutical applications, but, up to our knowledge, no study has been reported using this biopolymer as a powder component for the developing agent for latent fingermarks visualization. Besides being biodegradable and biocompatible, dextran shows non-toxic properties and thus prevents detrimental effect on humans often present when commercial chemical and physical methods are being routinely employed, while at the same time reduces the overall cost of the obtained powder system. Four different formulations of dextran-based micropowders were prepared with the aim of evaluating their performances in visualizing latent fingerprints. FT-IR analyses confirmed interactions between components of the systems. Optical microscopy showed that prepared powdered samples were small and uniform in size, while at the same time confirmed their easy binding to the sweat and lipid residues present in the latent trace. The results demonstrated that these novel dextran-based powders have the potential to supplement routinely employed physical systems in detecting and visualizing latent fingerprints

The influence of time on oxidation process of fluorescein-chitosan powder conjugates used to develop latent fingerprints on different substrates

Purpose: The application of fluorescent powders is of great significance for development of latent fingerprints on some unconventional substrates, such as firearms, skin, multicolored surfaces, etc. Therefore, researchers are constantly improving these formulations in order to increase their sensitivity and obtain adequate contrast. Design/Methods/Approach: This paper deals with chitosan-based powder systems conjugated with fluorescein (FL) and crosslinked with sodium-tripolyphosphate (Na-TPP), obtained by simple ionotropic gelation process. Prepared powders were used to visualize latent fingerprints deposited onto non-porous (glass), semi-porous (varnish paper) and porous (wood) surfaces, with the aim to enhance the quality of developed fingerprints by fluorescence assisted by ultraviolet (UV) light. The effect of time on oxidation of fluorescein in the conjugates used to develop traces was also investigated in order to determine whether the color change appears, as well as whether it affects the quality of the visualized fingerprints over time. Findings: Fourier-transform infrared spectroscopy (FT-IR) analyses confirmed interactions between components of the system and the formation of conjugates. Optical microscopy indicated that prepared powders show uniformity in shape and size, supporting binding to the sweat and lipid fingerprint residues. Originality/Value: Prepared powder showed good fluorescence under UV light and satisfying development of latent fingerprints deposited onto different substrates. The results indicated that prepared bio-based powder system could complement some of the routinely used (fluorescent) systems, particularly due to relatively low price and non-toxic (eco-friendly) properties.13 International Scientific Conference "Archibald Reiss Days", Belgrade, 8-9 November 202