Multi-element Characterization Research Articles

Influence of sand particle size on the erosion-corrosion resistance of Ni2FeCrMo0.2 HEA in seawater: Particle-surface-electrochemistry interaction

The erosion-corrosion mechanism in rotary flowing seawater is hugely complicated due to the multiscale coupling processes of particle-surface impact, ion mass transfer, and interface electrochemistry. Therefore, developing erosion-corrosion resistant material and exploring the synergistic mechanism between sand erosion and electrochemical corrosion is vital. This study conducted the erosion-corrosion test on Ni2FeCrMo0.2 high-entropy alloy under the particle-seawater flow. Based on a coupled analysis of multi-component weight loss, electrochemical behavior, and microscopic damage morphology, the multiscale coupling processes of sand transportation, particle-surface impact, ion mass transfer, and interface electrochemistry were revealed. The present study found that with the increase of sand size, the energy carried by the particles promoted impact erosion. Additionally, particle movement enhanced ion mass transfer through turbulent effects, and the impact behavior disrupted the passivation film to promote electrochemical processes by reducing the thickness of the passivation film, leading to an increase in the erosion-corrosion rate. However, when the particle size continued to increase to a certain extent, the impact frequency decreased, reducing the erosion-corrosion rate. As the sand size grew, the dominant damage mechanism transitioned from pure corrosion (100 μm) to synergistic effects (200 μm, 400 μm) and then to pure erosion (800 μm). This study provides an in-depth understanding of the erosion-corrosion mechanism in seawater from the perspective of particle-ion-fluid-surface interaction by multi-element characterization.

Multi-Elemental Characterization of Soils in the Vicinity of Siderurgical Industry: Levels, Depth Migration and Toxic Risk

Multi-Elemental Characterization of Soils in the Vicinity of Siderurgical Industry: Levels, Depth Migration and Toxic Risk

Multielemental Characterization of Bixa orellana L. (urucum) Seeds by Inductively Coupled Plasma Mass Spectrometry

Multielemental Characterization of Bixa orellana L. (urucum) Seeds by Inductively Coupled Plasma Mass Spectrometry

Isotopic (Cu, Zn, and Pb) and elemental fingerprints of antifouling paints and their potential use for environmental forensic investigations

Antifouling paints (APs) are one of the important sources of Cu and Zn contamination in coastal environments. This study applied for the first-time a multi-isotope (Cu, Zn, and Pb) and multi-elemental characterization of different AP brands to improve their tracking in marine environments. The Cu and Zn contents of APs were shown to be remarkably high ∼35% and ∼8%, respectively. The δ65CuAE647, δ66ZnIRMM3702, and 206Pb/207Pb of the APs differed depending on the manufacturers and color (−0.16 to +0.36‰, −0.34 to +0.03‰, and 1.1158 to 1.2140, respectively). A PCA analysis indicates that APs, tires, and brake pads have also distinct elemental fingerprints. Combining isotopic and elemental ratios (e.g., Zn/Cu) allows to distinguish the environmental samples. Nevertheless, a first attempt to apply this approach in highly urbanized harbor areas demonstrates difficulties in source apportionments, because the sediment was chemically and isotopically homogeneous. The similarity of isotope ranges between the harbor and non-exhaust traffic emission sources suggests that most metals are highly affected by urban runoff, and that APs are not the main contributors of these metals. It is suspected that AP-borne contamination should be punctual rather than dispersed, because of APs low solubility properties. Nevertheless, this study shows that the common coastal anthropogenic sources display different elemental and isotopic fingerprints, hence the potential for isotope source tracking applications in marine environments. Further study cases, combined with laboratory experiments to investigate isotope fractionation during releasing the metal sources are necessary to improve non-traditional isotope applications in environmental forensics.

Elemental Characterization of Leaded and Lead-Free Inorganic Primer Gunshot Residue Standards Using Single Particle Inductively Coupled Plasma Time-of-Flight Mass Spectrometry.

This study describes the use of single particle inductively coupled plasma time-of-flight mass spectrometry (spICP-TOFMS) for the detection and classification of inorganic gunshot residue (IGSR) particles. To establish reliable multi-element criteria to classify IGSR particles, leaded and lead-free IGSR reference materials were analyzed, and the elemental compositions of the individual particles were quantified. The results suggest that expanded element compositions may be used to classify IGSR particles via spICP-TOFMS compared to those used in conventional IGSR analysis using scanning electron microscopy energy dispersive X-ray spectroscopy (SEM-EDS). For spICP-TOFMS analysis of leaded IGSR particles, classification may be based on the presence of lead (Pb), antimony (Sb), and barium (Ba) just as in SEM-EDS; however, additional particle types, such as lead-copper (Pb-Cu) particles, contribute significantly (∼30%) to the leaded IGSR particle population. In lead-free IGSR particles, the dominate multi-metal particle composition found is titanium-zinc (Ti-Zn) with a conserved Zn:Ti ratio of 1.4:1, but other elements, such as copper (Cu), are also characteristic. In mixtures of the two IGSR reference materials, we were able to classify over 80% of the multi-metal particles detected with no false-positive particle-type assignments. With spICP-TOFMS, particles smaller than those typically measured by SEM-EDS are detected, with estimated median diameters for leaded and lead-free IGSR of 180 and 320 nm, respectively. Through measuring these smaller particles, up to ∼two times more particles per mL are recorded by spICP-TOFMS compared to that found by SEM-EDS. Overall, high-sensitivity and high-throughput analysis using spICP-TOFMS enables quantitative, rapid multi-elemental characterization, and classification of individual IGSR particles.

Multielemental Characterization of Chicken Breasts from Conventional and Sustainable Farms by Inductively Coupled Plasma – Optical Emission Spectrometry (ICP-OES) and Inductively Coupled Plasma – Mass Spectrometry (ICP-MS)

Sustainable chicken meat production has grown rapidly worldwide in the context of development. The study aimed to analyze macro (Ca, K, Mg, Na, P, S), micro (Cu, Mn, Rb, Sr, Zn), trace (Ba, Co, Cr, Ga, Li, Se, V), and toxic trace (As, Cd, Pb) elements in chicken breast meat from conventional and sustainable farms of South Korea. The elemental analyses were conducted by inductively coupled plasma – optical emission spectrometry (ICP-OES) and inductively coupled plasma – mass spectrometry (ICP-MS). The contents of Zn, Sr, Ba, Se, Li, and Ga were higher in sustainable samples compared to in conventional farms. The trace and toxic element contents were lower compared to recommended standard values. Chemometric tests, including principal component analysis (PCA) and linear discriminant analyses (LDA), together explained the highest variability index (100.0%). The outcomes of this study help in profiling the elemental composition of chicken breast meat from South Korean conventional and sustainable farms.

Multi-elemental Characterization of Semolina Samples by Inductively Coupled Plasma-Tandem Mass Spectrometry (ICP-MS/MS).

The precise characterization of the elemental composition of cereals and cereal products is becoming crucial to assess their nutritional values, geographical labeling, and also toxicological profile. Inductively coupled plasma-mass spectrometry (ICP-MS) has become popular for the elemental analysis of foods in recent years. Analytical performance of the inductively coupled plasma-tandem mass spectrometry (ICP-MS/MS) is improved with a reaction/collision cell that provides an interference-free analysis of most of the elements including phosphorus and sulfur. In this study, an analytical method was optimized for the quantification of 57 elements using ICP-MS/MS technique and validated for 25 elements that were available in certified reference materials (CRMs). Then, the mineral contents of semolina samples obtained from the durum wheat (Triticum durum) cultivars were analyzed according to the validation procedure. Recoveries of the elements were found in the range of 92-108% for the digested CRM. The method was robust for all elements and the results indicated good precision for the analytical method. The inter- and intra-day precision values were found below 5%, and in the range of 0.11-3.31% and 0.09-4.51%, respectively. Analyzed elements showed significant variability among the semolina samples. The variety and growing conditions might have influences on the elemental composition of semolina samples.

Physico-chemical and multielemental traits of anaerobic digestate from Mediterranean agro-industrial wastes and assessment as fertiliser for citrus nurseries.

Previous researches have demonstrated the bioenergetic potential of agri-food Mediterranean wastes showing that anaerobic co-digestion is a valuable solution for Mediterranean areas. This implies a great interest for anaerobic digestates use in agriculture to replace fertilizers. The present study aimed at: i) producing knowledge on continuous anaerobic co-digestion of feedstock mixture composed by different Mediterranean agri-food wastes in terms of multielemental characterization and ii) assessing the agronomic value of industrial anaerobic digestate (AD) based on the potential as fertiliser in nursery condition for the citrus seedlings. Results have demonstrated that agro-industrial biomasses have great potentiality to be converted by anaerobic digestion in biofertilizer to be used in citrus nurseries as sustainable alternative to mineral fertilisers. Multielemental traits of the tested AD were valuable in terms of nutritional supply for the growth and development of the plant. AD was useful to replace the mineral fertilizers in terms of total N content (10.81±0.32%TS) and organic matter (43.32±0.80%TS). The seedlings nutritive status showed that no need for supplemental of nutrients was requested. Volkamer lemon highly benefited from the administration of liquid digestate, increasing the total chlorophyll level (2.97±0.31mgg-1 FW) presumably due to the higher ammonium content of the AD (59±0.08%TKN). Besides providing useful tools for citrus nurseries for conceiving new sustainable fertilization strategies, this study is a starting point for further in-depth works on physiological status and traits of citrus plants fertilized by using agro-industrial anaerobic digestate.

Multi-Elemental Characterization of PM0.4–0.7 and PM1.1–2.1 in the Ambient Air of Isfahan (Iran) Complemented by the Speciation of Mn and Cr Using SR-XANES

In the present paper, we seek to study the interaction of desert dust and urban pollution in the particulate matter (PM) of an urban area of Isfahan, Iran, where anthropogenic and natural emission sources substantially contributed to the urban emission inventory. We used an eight-stage Anderson Cascade Impactor (ACI) for size-segregated sampling from the Isfahan PM for autumn 2017. According to the gravimetric analysis results, our study concentrated on the fractions with the largest mass concentrations, i.e. aerosols with sizes from 0.4 to 0.7 µm (PM0.4–0.7) and from 1.1 to 2.1 µm (PM1.1–2.1). We then employed chemical and optical methods for the multi-elemental characterization of the size-segregated particles and analyzing the interactions between the desert dust and urban pollution. The absorption-near-edge-structure (XANES) spectroscopy technique was also applied here for the speciation of Mn and Cr in the studied fractions. Our results showed that PM1.1–2.1 dominated by the dust particles, and particles originated by the fuel combustion have a significant contribution to the fraction PM0.4–0.7. The mass concentration of the iron element in the PM0.4–0.7 was higher than that in the PM1.1–2.1. The significant contribution of iron-rich particles to both studied fractions demonstrates that anthropogenic sources play an important role in the air quality degradation of the city. The interaction of desert dust and urban pollution was notably achieved in the fraction PM0.4–0.7, but the fraction PM1.1–2.1 is comprised predominantly of regular-shaped particles with the origin of natural sources (desert dust). XANES results argued that Cr and Mn species exist mainly in the trivalent and divalent oxidation states in the studied area, respectively. The weathering and surrounding conditions of the city could moderately develop the oxidation states of Cr and Mn.

Multielemental characterization of honey using inductively coupled plasma mass spectrometry fused with chemometrics.

Honey is considered a desirable ingredient in a range of different foodstuffs because of its nutrient and therapeutic effect. The honey characteristics mainly depend on the type of vegetation visited by the bees and the climatic conditions in which the plants are growing. Therefore, the purity, floral and geographical origin and authenticity are important factors influencing the overall perception of honey and honey-based products in terms of quality and price. An important parameter in this picture is the elemental composition of honey because it can be linked with the floral type of honey, floral plant density and the botanical origin of nectar and pollens. In this work, the concentration range variation of 18 elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Mg, Mn, Na, Ni, K, Pb, Sr, Ti, V and Zn) was investigated in four varieties of honey (linden, acacia, rape, and sunflower) originating from Romania, because the elemental profile of honey may give important information to differentiate its geographical and varietal origin for authenticity purpose. All the determinations were carried out by inductively coupled plasma quadrupole mass spectrometry (ICP-Q-MS). The most abundant minerals decreased in the following order: K > Ca > Mg > Na, having the mean values of 248.70, 59.97, 20.54 and 11.92 mg kg-1 , respectively. The mineral content marks the differences in honey samples from different botanical origin and can be used as a tool for authentication purposes and also extends its applicability to assess the traceability of honey. Analysis of variance showed the preliminary relationships between the elements and samples. Further, the discrimination between different studied honey samples was achieved by principal component analysis (PCA). The multivariate analysis of the data allowed us to separate the honey samples into distinct groups according to their macroelement and microelement composition, emphasizing the origin of variation of element concentrations by honey type. Therefore, this approach might be potentially useful for the control of honey quality, origin or authenticity, and even to use the honey as environmental tracer.

Red Earth, Green Glass, and Compositional Data: A New Procedure for Solid-State Elemental Characterization, Source Discrimination, and Provenience Analysis of Ochres

Ochres are a diverse category of naturally occurring iron-enriched earths and rocks, as well as iron oxide minerals, that derive their color from iron-containing chromophores and are suitable for use as pigments. Over the last two decades, provenience studies of archaeological ochres have grown from a rarity largely of interest only to specialists to an accepted and expected part of the archaeological science panoply. The most effective approach to distinguishing among sources of ochre and assigning archaeological pigments to their origin is multi-elemental characterization or “elemental fingerprinting.” In this study, we coupled a sample preparation method not previously used in ochre archaeometry with elemental fingerprinting by Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) and Electron Probe MicroAnalysis (EPMA). We present a procedure for lithium borate (LiBo) fusion of samples for solid-state analysis, optimized for use with ochres, and designed for the budget and laboratory equipment constraints faced by many professional and student archaeologists. This method development research is part of the broader project “OLKARIA: Ochre Landscapes of Kenya – Anthropological Research and Iron-oxide Archaeometry,” which seeks in part to characterize the elemental composition of all known geologic ochre sources in the Kenya Rift Valley. Using a subset of project OLKARIA samples prepared by LiBo fusion and measured with LA-ICP-MS and EPMA, we successfully distinguished among six geologic ochre sources and a sample of commercially available iron oxide pigment. Our ability to uphold the Provenience Postulate for this data set compared favorably with source discrimination analyses done using data from Neutron Activation Analysis (NAA) of whole ochre for the same samples. LiBo fusion presents potential solutions to some criticisms of solid-state analysis of ochre using beam techniques, including issues arising from mineralogical heterogeneity, variable surface topography, the presence of free and chemically bound water, and the lack of matrix-matched standard reference materials. We also address the challenges of applying compositional data analysis best practices to ochre with an emphasis on the issues of rounded zero replacement and multivariate normality and highlight the work that remains to be done in this area.

Characterization of soil, sediment, and wastewater samples from hydraulic fracturing processes using the comparative NAA method

Regulatory monitoring of oil and gas development requires the accurate multi-elemental analysis of wellbore samples on a regular basis. In this study, an unconventional method, comparative neutron activation analysis (comparative NAA), was applied for the multi-elemental characterization of solid and liquid hydraulic fracturing samples at the ppm level. The obtained values from three wastewater samples were compared with the most probable values determined via an inter-laboratory study, which involved 15 different laboratories from the United States, Canada, and Germany. The comparison showed that 15 out of 19 comparative NAA trace element concentration values were considered acceptable, providing a new technique to determine elemental concentrations in high salinity hydraulic fracturing samples.

Sugar Press Mud as a Proposed Futuristic Aqua-fertilizer - Multi-Elemental Quantitative Characterization by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES)

Sugar Press Mud as a Proposed Futuristic Aqua-fertilizer - Multi-Elemental Quantitative Characterization by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES)

A new method based on low background instrumental neutron activation analysis for major, trace and ultra-trace element determination in atmospheric mineral dust from polar ice cores

Dust found in polar ice core samples present extremely low concentrations, in addition the availability of such samples is usually strictly limited. For these reasons the chemical and physical analysis of polar ice cores is an analytical challenge. In this work a new method based on low background instrumental neutron activation analysis (LB-INAA) for the multi-elemental characterization of the insoluble fraction of dust from polar ice cores is presented. Thanks to an accurate selection of the most proper materials and procedures it was possible to reach unprecedented analytical performances, suitable for ice core analyses. The method was applied to Antarctic ice core samples. Five samples of atmospheric dust (μg size) from ice sections of the Antarctic Talos Dome ice core were prepared and analyzed. A set of 37 elements was quantified, spanning from all the major elements (Na, Mg, Al, Si, K, Ca, Ti, Mn and Fe) to trace ones, including 10 (La, Ce, Nd, Sm, Eu, Tb, Ho, Tm, Yb and Lu) of the 14 natural occurring lanthanides. The detection limits are in the range of 10−13–10−6 g, improving previous results of 1–3 orders of magnitude depending on the element; uncertainties lies between 4% and 60%.

Laser ablation inductively coupled plasma mass spectrometry investigation of late 19th Century Blaschka marine invertebrate glass models

Micro-destructive Laser Ablation Inductively Coupled Mass Spectrometry (LA-ICP-MS) was used to obtain a unique multi-elemental characterization for late 19th century glass. This study describes detailed analysis of glass and enamels from 45 of 187 glass models of invertebrate sea creatures made by Leopold and Rudolf Blaschka and acquired by The Natural History Museum, London in 1866, 1876, 1883 and 1889. Although it is not possible to establish the nature of individual raw materials used for the manufacture of these glasses it was found that all four batches contain mixed alkali glasses of very similar composition. Discrimination between melting batches and different suppliers was possible by investigating trace element patterns. Lead glasses, representing 20% of the colourless glasses analysed, are present in three acquisition batches, and are more heterogeneous, showing clear chronological segregation and varying levels of As. Soda Lime Silicate glass was found in only two samples. All 38 coloured glasses contained extremely high PbO; levels of colouring ions and colouring and/or opacifying crystals are described, providing clues to the decoration techniques employed by the Blaschkas for the first two batches. Identical structures found on the same model sometimes had different compositions, while anatomical structures requiring similar processes to be made shared identical glass compositions. This confirms the Blaschkas worked by producing many items in batches for assembly rather than creating each model from scratch on demand. Surface treatments and surface conditions such as on-going degradation processes were identified through depth profiling but in general all glass analysed appeared very well preserved. This information can be used to plan the conservation of Blaschka objects, appropriate storage and display conditions.

Synergetic inhibition of thermochemical formation of chlorinated aromatics by sulfur and nitrogen derived from thiourea: Multielement characterizations

Nitrogen and sulfur (N/S)-containing compounds inhibit the formation of polychlorinated dibenzo-p-dioxins (PCDDs) and furans (PCDFs) in thermal processes. However, few studies have examined the inhibition mechanisms of N/S-containing compounds. In the present study, we focused on thiourea [(NH2)2CS] as such a compound and investigated its inhibition effects and mechanisms. The production of PCDD/Fs, polychlorinated biphenyls (PCBs), and chlorobenzenes (CBzs) were inhibited by >99% in the model fly ash in the presence of 1.0% thiourea after heating at 300°C. Experimental results using real fly ash series were indicative of the thermal destruction of these chlorinated aromatics by thiourea. Multielement characterization using K-edge X-ray absorption fine structures of copper, chlorine, sulfur, nitrogen, and carbon revealed three possible inhibition paths, namely, (a) sulfidization of the copper catalyst to CuS, Cu2S, and CuSO4; (b) blocking the chlorination of carbon via the reaction of chlorine with N-containing compounds to generate ammonium chloride and other minor compounds; and (c) changing the carbon frame involved in attacking the carbon matrix by sulfur and nitrogen. Thus, thiourea plays a role as a sulfur and nitrogen donor to achieve multiple and synergistic inhibition of chlorinated aromatics. Our results suggest that other N/S-containing inhibitors function based on similar mechanisms.

Characterization of commercially available products of aronia according to their metal content

Introduction. Among different fruit species, aronia have attracted a great attention because of its wide range of protective effects with potential benefits for human health. Furthermore, the consumption of products of aronia (juice, tea, berries) is becoming a part of a healthy lifestyle. Materials and Methods. The multi-element characterization of products of aronia has been carried out using inductively coupled plasma atomic emission spectrometry (ICP-AES). Results and Discussion. Among the major elements, the most abundant are K, Ca and P, followed by the Mg and Na. Fe, Zn, Mn, Cu, Bi and Si are the most abundant among the microelements. In terms of heavy metals (As, Cd, Pb), it can be concluded that the concentrations of them are below permissible levels (PLs) prescribed by national legislation in all samples. The chemometric techniques of principal component analysis (PCA) and cluster analysis (CA) were used to differentiation of products aronia according to their metal content. The application of PCA and CA was resulted in two clusters with similarities in the mineral composition. The first cluster includes tea bag samples (T1-T6). The second cluster includes berries (B1, B2), juices (J1-J4) and leaves (L). Conclusion. Data obtained in this study showed that analyzed products are potentially a rich source of some dietary metals such are K, Ca, P, Mg, Na, Fe and Zn. Obtained results could be also used as selection criteria for further use of products of aronia as a part of conventional diet.

Relationship between tectonic structures and hydrogeochemical compartmentalization in aquifers: Example of the “Jeffara de Medenine” system, south–east Tunisia

Abstract Study region “Jeffara de Medenine” aquifer system in south-eastern Tunisia. Study focus This study investigates the role of fault structures in the distribution of hydrogeochemical facies and groundwater compartmentalization for the aquifer system. New hydrological insights for the region The proposed methodology, including seismic structural study, hierarchical cluster analysis and geostatistical methods, allowed an efficient multi-element characterization of the spatial patterns of the structural elements in the aquifers and of the hydrogeological parameters used in a spatial cross-correlation to explore the dependence of the geochemical properties in each “geochemical population” on the hosting structural compartment to delineate the different geochemical compartments. The tectonic studies showed that the lateral extent of the aquifers is controlled by normal faults. The multivariate statistical analysis revealed a strong spatial coherence between hydrogeochemical facies clustering and the reservoir compartments at both large and small scales. The kriged maps of major-ion concentrations and of total dissolved solids in the aquifers were then analyzed and compared with the reservoir facies distribution for each compartment, the geometric characteristics of the aquifer, and the piezometric level trends. This allowed to characterize the hydraulic behavior of the Medenine fault and to understand the underlying physical and chemical processes having led to the spatial distribution of the geochemical properties, and thus, the hydrogeochemical functioning of the aquifers.

Optimization and Validation of a Microwave Digestion Method for Multi-element Characterization of Vranec Wines

An analytical method for determination of multi-element composition of Vranec wines using microwave digestion for sample preparation and inductively coupled plasma mass spectrometry (ICP-MS) was optimized and validated. Best recoveries, ranging from 87 to 114 %, were obtained for all analyzed elements, using a volume of 5 mL wine and 5 mL HNO3 for sample microwave digestion. In total, 38 elements (Ag, Al, As, B, Ba, Be, Bi, Ca, Cd, Co, Cr, Cs, Cu, Fe, Ga, Ge, In, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Pd, Rb, S, Sb, Se, Si, Sn, Sr, Te, Ti, Tl, V, Zn) were determined in wines. The calibration curves of all elements were linear with correlation coefficients (R 2) ranging from 0.9920 for 11B to 1.0000 for 53Cr and 88Sr. The accuracy of the method was checked with a standard addition method showing good repeatability and reproducibility (relative standard deviation, RSD <10 %). Vranec wines were fermented with Saccharomyces cerevisiae yeast strains commercial Clos, RC212, D254, and BDX, and six autochthonous Vinalco yeasts. The content of total elements in all Vranec wines ranged between 348 to 678 mg/L, observing lower amounts in wines fermented with the autochthonous Vinalco yeast. The content of harmful elements, such as Pb and Cu, was below the maximal allowed concentration in all wines.

Multi-element characterization of archaeological floors at the prehistoric archaeological sites at Ban Non Wat and Nong Hua Raet in Northeast Thailand

This paper reports the results of geochemical analysis of hard floor sediment samples from the prehistoric Mun river valley occupation sites of Ban Non Wat and Nong Hua Raet in Northeast Thailand. Past human activities leave the chemical residues on the activity floors as an evidence for those activities. We examined the soil chemistry of compacted sediment features identified archaeologically as floors and sediments from the general spits and off-site natural soils, using standard chemistry-based method of inductively coupled plasma-mass spectroscopy. The results showed high levels of phosphorus, calcium, potassium and iron present in hard floor areas which was the most domestic activities took place. These results provide important information for the understanding of hard floor surfaces which has been found as compacted sediment layers in the excavations. Chemical analysis revealed key anthropogenic elements in the soil features of the hard floors to be phosphorus, calcium and potassium which reflect the occupation intensity of ancient people in different floor surfaces.