Fingerprints are one of the most present and valuable pieces of physical evidence in forensic science and can often, to some extent, be found at the crime scene. These marks, a series of ridges and furrows and their random combinations on the finger surface [1,2], are assumed to be unique for every person, pointing out that there are no two people on Earth that have identical fingerprints [3]. There are three distinct types of fingerprint: patent, plastic, and latent, that could be recovered from the crime scene [4,5]. On the other hand, latent fingerprints are impressions secreted on a surface and are usually imperceptible [6-8]. Identification of these latent fingerprints is one of the most important tasks for law enforcement agencies in order to identify persons suspected of having committed a crime [3]. Fingerprint detection and analysis for individual identification has undergone tremendous changes since its introduction to the investigation of crimes in 1892 [9,10]. Many approaches are used for their visualization, but two main and routinely employed are

This article presents the study of direct dye sorption onto the flax fiber during the dyeing process in the presence of an inorganic electrolyte. The previously prepared linen fabric was subjected to dyeing by a standard process, varying in concentration and time of dyeing. The results are satisfactory considering that they reveal the character of the direct dye sorption for fibers as well as the capacity and energy adsorption, on the basis of which the process of dyeing can be optimized. The increase of dye concentration in the solution during dyeing decreases, and longer time of dyeing increases the degree of exhaustion. The adsorbed amount of adsorbate on the adsorbent rises during the increase of initial concentration and dyeing time. Langmuir, Freundlich, Temkin and Flory-Huggins models can be used to describe adsorption of a direct dye onto the linen fiber, having in mind the advantage of Flory-Huggins model because of its characteristics in the description of the sorption and maximum values of the coefficient of determination as well.

The study deals with modeling of linen fabric dyeing after previous scouring and bleaching. The results reveal the process of the direct dye adsorption on the fabric, as well as the capacity and energy of adsorption based on which the optimization of the dyeing process with maximum performance and minimal costs can be done. With the increase of the dye concentration during dyeing, the degree of exhaustion decreases while the longer dyeing time gives a higher degree of dye exhaustion. Variation in the adsorbed amount of adsorbate increases with the increased initial concentration and time, i.e. a bigger amount of the dye or a longer time period of dyeing causes a bigger quantity of the adsorbed dye per mass unit of the linen fabric. The advantage in results processing is given to Freundlich-s model since the maximal value of the determination coefficient can be obtained.

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.

The new knowledge through a concrete scientific study of the dyeing process of polyamide filament yarns (nylon yarn) with anionic dye in slightly acidic medium without any other additives (electrolyte, yeast, equalizer, etc.) in order to transfer the process in industrial conditions have investigated in this study. Generally, polyamide fibers (nylon, PA) have a different but similar chemical composition, depending on the base materials used for their synthesis. Anionic dye is usually used for dyeing cellulosic materials, but in special cases it can also be used for dyeing other textile raw materials. In this study, samples of polyamide filament yarn of linear density of 151 Nm have dyed with anionic dye at a temperature of 95 °C. Acetic acid was added in the dyeing solution to adjust the pH of the medium. The used dye is marked like C.I. Direct Red 1. The used dye concentrations for dyeing the samples were 5, 10, 15 and 20 mg/dm3, while the time of the dyeing process were 5, 10, 15, 25 and 40 minutes. At the end of dyeing, the absorbance measuring at the maximum wavelength (520 nm) was performed using a spectrophotometer (Cary 100 Conc UV-VIS, Varian). From the results, the degree of exhaustion dye and the amount adsorbed dye are obtained. The degree of dye exhaustion compared to initial dye concentration for different dyeing time, after 40 min was 70 %. The influence of the contact length between adsorbate (dye) and absorbent (polyamide yarn) on dye is evident i.e. a longer time contributes to a bigger degree of exhaustion. Changing the adsorbed amount of adsorbate on the adsorbent for different initial concentrations and dyeing time shows continuity in changes during initial concentration and time growth, i.e. a bigger amount of dye in the solution or longer dyeing time cause a bigger amount of adsorbed dye per unit mass of the adsorbent. Isotherms of adsorption are of big importance for the study of the dyeing process, so more of them were used in this study, but thee isothermal Halsey model was the most effective for clarifying process of dyeing. High functionality of the variables was detected with Halsey model (coefficient of determination=0,995). The process of dyeing polyamides with used dye solves the problem of large quantities of electrolytes and surfactants in wastewater after dyeing. The results show that the addition of acetic acid in solution, gives a bigger dye adsorption to the fiber. For better results, it is necessary to carefully select to the appropriate of the bath (appropriate acid, mineral-organic, some additives, etc.), the temperature-time regime od dyeing process, as well as the dyeing stage itself. For better results, it is necessary to carefully select the appropriate composition of the bath (appropriate acid, mineral-organic, some additives, etc.), the temperature-time regime of the dyeing process, as well as the dyeing phase.