Background and Aim: The aim of this study was the evaluate using of techniques LIBS (laser-induced breakdown spectroscopy) to detect biological agents in bioterrorism threat. Remote and real-time identification of biological agents is now one of the key needs for defense and security dimensions in the world.Methods: In this study, has been used a descriptive method that after collecting the literature and the internet search.Results: LIBS technique based on laser-induced plasma spectroscopy can lead to determining of amount various elements in the microorganisms. In this method, in place of laser focus was evaporate a small amount of the target surface and on the impacts of successive molecules in the vapor phase, was break the molecular bonds which the atoms and ions excited were create laser induced plasmas.Conclusion: Detection of bioterrorism threats by means of light and simple at the online and distant is very important. According to the results of the research showed that LIBS technique is used to detect bioterrorism threats and its utilizations is being rapidly developed for the detection of biological agents.

Due to the limitations of conventional biological identification methods, spectroscopic methods, including laser induced breakdown spectroscopy, have been used to characterize the genus, species and strains of different bacteria in the static phase of growth. Due to the increading importance of biological problems, the characterization, detection and classification of bacterial specimens has been considered by researchers in the military, industrial and medical fields. In this paper, in order to monitor the changes in the elemental structure of bacteria in the growth process, the constituent elements of the two phases of exponential and static growth of Escherichia coli were studied and compared based on this spectroscopic method. In this experiment, Nd: YAG laser with 100 mJ pulse energy, spectrometer and CCD detector were used. The industrial strain of gram-negative Escherichia coli BL21 bacteria was selected. Bacteria were selected at three different times (2. 5, 4 and 6 hours after inoculation) during the growth process in broth, at optical density of 0. 4 and 0. 8 (exponential growth phase) and optical density of 1. 2 (Static growth phase), respectively, and after dry freezing, under pressure has been pressed into tablets. Considering the chemical structure of Escherichia coli, the elements of phosphorus, carbon, calcium, sodium, magnesium, potassium, oxygen, nitrogen and hydrogen were considered in the sample. The results showed that Escherichia coli bacteria in the growth process have different patterns of recognizable elemental composition in its structure in the growth process. It is predicted that due to the change in the composition of structural elements of bacteria in growth phases, the use of this spectroscopic method to identify bacteria will be dependent on the growth phase. The results of this study showed that this method can play an effective role in the development of polyphasic methods to indentify bacteria, determine the composition of the culture medium as well as optimizing and evaluating the production conditions in this industrial strain.

Growing plastic waste emission as a planetary threat urges the development of a rapid and efficient recycling process, especially during the classification process. Herein, we aimed to solve the problem by employing laser-induced breakdown spectroscopy (LIBS) in combination with principal component analysis (PCA) as means for automated plastic waste classification. Samples used in the study were plastic wastes derived from beverage, food, and stationery products of different brands. The Nd:YAG laser was shot to the sample surface without a pre-treatment and under an open-air system (laser energy= 54 mJ; time delay= 1-2 μs). The spectral profile of each plastic waste revealed the presence of metal components such as those indicated by Ca II 396.85 nm, Al I 395.92 nm, Mg I 383.83 nm, and Fe I 404.85 emission lines. Peak intensities of organic material-related emission lines (C I 247.86 nm, O II 777.32 nm, O I 844.48 nm, H I 666.22 nm, N II 818.83 nm, and N II 821.62 nm) were revealed fluctuating, suggesting that a mere LIBS spectral analysis could not discriminate the plastic waste. PCA analysis revealed that C2 molecular band 490—520 nm had the most discriminative properties against polyethylene terephthalate (PET) and polypropylene (PP). The molecular band was generated differently between PET and PP because of their contrast thermal behavior. In conclusion, molecular LIBS-PCA could be used to distinguish PET and PP in a simple and rapid way.

In addition to reading historical books and texts, an examination of the natural and artificial artifacts left over from the past can also provide a comprehensive and appropriate view of human life style. Pottery is a work of art, due to their nature as well as their compositional structure, has been able to retain its originality for many years and present itself as a viable option for study purposes. Despite the widespread use of both Micro-Raman Spectroscopy, and Laser-Induced Breakdown Spectroscopy (LIBS) techniques in the world of archeology, these study methods are still unknown within the country and have not been applied to the study of artwork in accordance with their global status. Careful study of historic Arg-e Bam pottery is done for the first time in the country in a scientific and practical way, in order to reveal some of the historical and artistic aspects of these works. Studies also show that in the Middle Ages and during the Seljuk, Khwarezmshahi, Ilkhanid and Timurid rule to beautify and extend the life of pottery from seven types of matte turquoise blue glaze, matte milky glaze, clear turquoise blue glaze, milky gray glaze, monochrome glaze, embossed glaze and also golden glaze were used. The current paper applies both above mentioned study methods, following a comprehensive review of the nature of glazes used in the pottery industry and their historical antiquity. The results of the study are then described on seven samples of historic Arg-e Bam pottery to illustrate the source of cobalt oxide for blue, chromium and copper glazes for green and turquoise glazes as well as tin for white glazes. Keywords: Arg-e Bam, Pottery, Glaze, Micro Raman Spectroscopy, Laser-Induced Breakdown Spectroscopy (LIBS).     Introduction One of the most important and main ways to be aware of the style and context of human life throughout history is to study the objects made by them, especially works of art. Considering that clay objects have the ability to maintain their originality for many years and remain intact in the face of various dangers; Archaeologists and researchers have always been interested in various studies. On the other hand, by combining archeology with other sciences such as physics, chemistry, etc., more accurate and reliable analyzes can be achieved, and as a result, a clearer picture of the past lifestyle of human beings can be obtained. In this research, using Raman spectroscopy and Laser-Induced Breakdown Spectroscopy (LIBS), studies have been conducted on the origin and structure of glazes on a number of pottery of the historic citadel of Bam. Using this study method on glazed pottery, in addition to requiring a short time, can provide us with complete information about the structure, contents and history of these samples. In this research, it is shown that these two spectroscopic methods are able to determine and introduce the materials used in the production of glaze on Pottery samples with a high reliability coefficient. It can be said that the first generation of glazed pottery found in Bam belongs to the Sassanid period, at the end of the historical period, which archaeologists consider to be rough blue glazed pottery related to this period. Researchers believe that the Bam region in the Islamic era was much richer in terms of pottery and its species diversity than the two prehistoric and historical periods; Because most of the pottery discovered in this area belongs to the Islamic era. In the leading research, the word glaze and the necessity of using it in the pottery industry are first introduced. In the next step, the history of pottery discovered from Bam citadel and also the use of glaze in these samples were reviewed and then, by introducing materials and study methods, the common materials used to produce different types of glaze in different colors were introduced. Finally, by examining seven samples of pottery in the historic citadel of Bam, we will talk about the characteristics of the glazes used to cover these samples, as well as the results obtained from this research.   Discussion Ceramic glaze is an impervious layer or coating of a vitreous substance which has been fused to a ceramic body through firing. Glaze can serve to color, decorate or waterproof an item.[1] Glazing renders earthenware vessels suitable for holding liquids, sealing the inherent porosity of unglazed biscuit earthenware. It also gives a tougher surface.   Green and Turquoise Glazes: Copper oxide: It is one of the most widely used colored oxides that has been used since ancient times to produce green glazes by potters and artists. Zinc oxide: By using this material and copper oxide at the same time, a turquoise color can be created in different glazes. Chromium oxide: The use of this material together with one of the alkaline metals in the structure of the glaze makes its color green. The green color created in this way has a very good stability.   White Glazes Tin oxide: This material is generally used for the purpose of opaque and opaque different glazes, but if we use only tin oxide and lead in the production of glaze, then after heating it, a white and milky glaze is obtained. For experiments in this research, a green laser Raman microscope with a wavelength of 532 nm was used. The intensity and amount of Raman rays scattered from the surface of each sample is a function of the location and three-dimensional arrangement of its constituent atoms in space relative to the other components. With this description, the Raman signal received from the sample surface can be introduced as a fingerprint identifier that can play an important role in identifying materials. Also for LIBS spectroscopy method, (In this spectroscopic method, a small part of the material is converted to plasma using a laser as a light source).  Nd: YAG Q-Switch laser with a wavelength of 532 nm, a pulse width of 10 nanoseconds and a repetition rate of 3 Hz is used.   Conclusion in the study of pottery discovered from the historic citadel of Bam using the Raman spectroscopy method, it was found that cobalt oxide was generally used to create blue glazes in the coating of these materials. But in one of the samples, the presence of azure or Lapis lazuli was also visible. In addition, while copper oxide can be introduced as the most important factor in the formation of green glazes in the above samples, the study of the range obtained from a number of samples showed that chromium ions are the main structure of their green glazes. In addition, it was confirmed that in white glazes, a sudden increase in the band in the 500 region could be evidence of the presence of tin oxide in the glaze structure. The use of laser induction sales spectroscopy also showed that copper-dependent compounds and most likely copper oxide were generally used to prepare the blue glazes on these pottery. The identification of copper radiation lines in the spectra obtained from samples 2, 4, 5 and 6 is a good confirmation and expression of this issue. On the other hand, in the study of samples 1, 4 and 7, it was found that the glazes of these materials, while containing copper-dependent compounds, were prepared using compounds prepared from chromium (most likely chromium oxide) and the application of different percentages of this Two materials during the preparation and baking of the glaze have caused us to see a range of different colors from green to turquoise on these samples. Although it was expected that cobalt radiation lines could be found in some of these samples, the presence of this element and its related compounds, such as cobalt oxide, was not found in any of the obtained spectra. In the sample review section, it was also shown that in white glazes, it is possible to identify elements such as tin, barium and titanium, and these elements are responsible for creating this color in the glazes of samples 6 and 7. Examination of the glaze structure on these 7 samples also showed that only one of them has a glaze of lead nature and lead lines are visible only in sample 3.

A significant feature of alloys is their surfaces hardness which its measurement by common mechanical techniques is always accompanied by challenges. In this investigation, we used Laser Induced Breakdown Spectroscopy (LIBS) as a replacement method for common mechanical techniques employed for the surfaces hardness measurement of different alloys. After recording the spectrum of alloy samples, K-Nearest Neighbors (KNN) method was used in order to identify the surface hardness of analyzed sample. The obtained results showed that the LIBS-KNN method can distinguish and identify the surfaces hardness of samples with 93. 3% accuracy. In addition, in order to identify the percentage of constituent elements of alloys and their hardness, calibration approach was applied showing that there is an appropriate linear relation between recorded emission lines from the LIB spectra of sample alloys and the percentage of their constituent elements as well as their Vickers hardness numbers. Therefore, considering the exclusive advantages of LIBS technique, its high speed analysis, its non-destructive analysis and being portable, some of the current difficulties in conventional mechanical techniques can be removed.

Purpose Agronomic and environmental reasons force farmers to know the total P concentration of composted cattle manure. Laser-Induced Breakdown Spectroscopy seems proper to obtain such information. For logistic reasons (carriage, storage, field application, etc. ), a dry matter characterization is also needed. Method Thirty samples of feedlot compost at different stages of stability and maturity were studied. Samples were dried at 50°, C for dry matter characterization. As a reference method to determine total P concentration, wet digestion and colorimetry were employed. The area of the P I line emission obtained by laser-induced ablation of the samples was measured to estimate the total P concentration. Randomized calibrations through a modified version of the Kennard-Stone algorithm based on the Mahalanobis distance were performed. Results Dry matter varied from 40% to 90%, and no pattern was found related to compost origin, maturity, or stability. The total P concentration of the studied compost ranged from 1800 ppm up to 11200 ppm. Almost 80% of the calibration fittings have an R2 ≥,0. 895. The mean validation error was less than 22% for about 80% of the calibrations, with a mean prediction error bound to 40%. Discarding outliers, the errors were reduced to 19% and 30%, respectively. Conclusion Water content must be considered in addition to other characterizations due to logistic implications. Calibrations with a 30 percent of prediction error were achieved, which seems enough as a first approximation to predict the total P content in compost for utilization in farms to recycle nutrients.

Along with the development of laboratory methods for diagnosing addiction, concealment ways for creating false results, either physically or chemically, have been in progress. In this research, based on the Laser Induced Breakdown Spectroscopy (LIBS) technique and analyzing hair of addicted and normal people, a new method is proposed to overcome problems in conventional methods and reduce possibility of cheating in the process of diagnosing addiction significantly. For this purpose, at first, we sampled hair of 17 normal and 17 addicted people and recorded 5 spectrums for each sample, overall 170 spectrums. After analyzing the recorded LIBS spectra and detecting the atomic and ionic lines, as well as molecular bands, relative intensities of emission lines for Aluminum to Calcium (Al/Ca) and Aluminum to Sodium (Al/Na) were selected as the input variables for the Support Vector Machine (SVM) model. The radial basis and polynomial Kernel functions as well as a linear function were chosen for classifying the data in SVM model. The results of this research showed that by the combination of LIBS technique and SVM one can distinguish addicted person with precision of 100%. Because of several advantages of LIBS, such as high speed analysis and being portable, this method can be used individually or together with available methods as an automatic method for diagnosing addiction through hair analysis.

Introduction: A modern technique for elemental analysis of biological samples is laser induced breakdown spectroscopy (LIBS). This technique is based on emission of excited atoms, ions, and molecules in plasma produced by focusing a high power laser pulses on sample surface. Because of several advantages of LIBS including little or no sample preparation; minimally invasive; fast analysis time and very easy to use, in this study, this method was used for investigating the mineral content of fingernails. As the trace element of nail can be changed by several pathological, physiological, and environmental factors, we analyze the human fingernails to evaluate the possibility of thyroidism diagnosis.Method: A Q-switched Neodymium-Doped Yttrium Aluminium Garnet (Nd:YAG) laser operating at wavelength of 1064 nm, pulse energy of 50 mJ/pulse, repetition rate of 10 Hz and pulse duration of 6 ns was used in this analysis. Measurements were done on 28 fingernails belonging to 5 hypothyroid, 2 hyperthyroid and 21 normal subjects. For classification of samples into different groups based on thyroid status, a discriminant function analysis (DFA) was used to discriminate among normal and thyroidism groups.Results: The elements detected in fingernails with the present system were: Al, C, Ca, Fe, H, K, Mg, N, Na, O, Si, Sr, Ti as well as CN molecule. Classification in two groups of normal and patient subjects and also in three groups of normal, hyperthyroid and hypothyroid subjects shows that 100% of original grouped cases were correctly classified. So, efficient discrimination among these groups is demonstrated.Conclusion: It is shown that laser-induced breakdown spectroscopy (LIBS) could be a possible technique for the analysis of nail and therefore identification of health problems.

Laser-induced breakdown spectroscopy (LIBS) is a new approach for determination and characterization of various nanomaterials structures. In this work, LIBS emission spectra of different species of nanocarbon nanomaterials (carbon allotropes) were described. Ablation was performed using an Nd: YAG laser at 1064 nm in ambient air at atmospheric pressure. Results are consistent with the atomic emission lines of carbon or molecular bands, C2 being released directly from the target, and CN being formed later by the interaction of C2 with nitrogen gas (N2) in the atmospheric ambient of plasma. It was indicated that probably there is a relationship between C2 emission from the plasma and the presence of aromatic rings (containing carbon-carbon double bonds) in the compounds.