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Environmental pollutions are considered a significant challenge in all human societies. Heavy metals, recognized as fundamental environmental pollutants, enter the environment through human activities and can pose various environmental hazards. In this study, a comprehensive investigation of environmental pollutions in Aligudarz County is considered as a strategic point in Iran and serves as a model for similar studies worldwide. The research utilizes geochemical, mineralogical, and statistical approaches to examine pollutions, providing innovative and quantitative insights into understanding the geochemistry of the environment and the relationship between pollutions and environmental factors. The results indicate that the study area is subject to moderate to severe pollution from toxic elements, including molybdenum, lead, cadmium, and copper. These pollutions are correlated with the geochemical, mineralogical, and environmental analysis of the region, and the information derived from this study contributes to environmental management and protection. Considering the research findings, this research model can serve as a global template for environmental studies, playing a crucial role in enhancing understanding of pollutions and advancing knowledge in this field. Therefore, the current research has a broad impact on fostering innovations and advancing knowledge in pollution management and environmental conservation. [ABSTRACT FROM AUTHOR]

This study aims to differentiate between Cu-Mo and Cu-Au porphyry deposits within Iran through fractal modeling, utilizing the Mo/Au geochemical index as a primary determinant. Employing the Concentration-Number (C-N) fractal model, the Mo and Au values within Iranian copper porphyry deposits were comprehensively classified. The findings from the fractal modeling reveal distinct criteria for separating these deposits. Cu-Mo porphyry deposits are identified by Mo concentrations ≥141 ppm, while Cu-Au porphyry deposits are characterized by Au concentrations ≥398 ppb. The pivotal threshold for the Mo/Au ratio stands at 1585, facilitating the division between these distinct types of porphyry deposits. Within the Urumieh-Dokhtar magmatic arc, numerous Cu-Mo porphyry deposits, exemplified by globally recognized sites like Sarcheshmeh and Sungun, are prevalent. Conversely, Cu-Au porphyry deposits are found in the NW and SW regions of the Urumieh-Dokhtar magmatic arc and eastern Iran, typified by occurrences like Dalli. The study's findings reveal a correlation between geological characteristics and the ages of porphyry deposits, indicating that those formed during the Miocene period and later are predominantly of the Cu-Mo (Copper-Molybdenum) porphyry type. [Display omitted] • Separation Cu-Mo and Cu-Au porphyry deposits in Iran • Using fractal modeling based on a geochemical index as Mo/Au • There are Cu-Mo porphyry deposits with Mo ≥ 141 ppm. • Cu-Au porphyry deposits are distinguished by Au ≥ 398 ppb. [ABSTRACT FROM AUTHOR]

Testing and developing nutrient diagnosis methods, which can result in the optimum production of fruits, is of significance. The nutritional balance and requirements of almond (Prunus sp.) orchards, in the city of Saman (province of Chaharmahal and Bakhtiari, Iran, one of the biggest producers of almond in the country), were investigated using the methods of diagnosis and recommendation integrated system (DRIS) and deviation from optimum percentage (DOP) in a two-year research. Using 36 gardens along the Zayandehrud River in a 60-km distance, soil physical and chemical properties, as well as leaf micro- and macro-nutrient contents were determined. Similar plant samples (leaf + petiole) in terms of age, genotype and rootstock were collected from the unfruitful trees. The most deficient nutrients including S, Cu, Zn and Mn were indicated by the DRIS and DOP methods. However, according to the DRIS method Mg, and according to the DOP method N, K and Mg were determined as the most excessive macronutrients. Interestingly, both methods indicated Mo as the most excessive micronutrient. The balance indexes of different nutrients for different orchards indicated that the nutritional balances of the orchards from the highest to the least deficiency are according to the following order Cu > S > Zn > Mn > Cl > P > Ca > Mg > B > N > K > Fe > Mo. Such results indicate the precisions and some similarities between the two methods. However, the two methods were compared using SAS Proc GLM, Proc REG, and Proc NLIN. The analyses indicated that the two methods were significantly different and the DOP method (significant model) indicated higher correlation with the results. Accordingly, the DOP method may be a more accurate method of estimating almond yield as affected by the concentration of different nutrients. It is possible to determine the deficiency, balance and excessiveness of nutrients in almond orchards using the DRIS and DOP methods, which is of economic and environmental significance, worldwide. [ABSTRACT FROM AUTHOR]

One of the most crucial components in risk management in an organization is detection of risk modes in a system, prioritization of them and making plans in order to enact corrective actions. And one of the common methods for prioritization of risks is the conventional Failure Mode Effects Analysis (FMEA). Although this approach is widely used in different industries, it suffers from some shortcomings, which can lead to failures in reaching reality-based results. This research study, therefore, proposed an approach in three phases for the compensation of the shortcomings of the FMEA method. In the first phase, the FMEA method was used to detect different risk modes and then assign values to the Risk Priority Number (RPN) determinant factors. In the second phase, the weights of the triple factors were calculated by means of Fuzzy Best-Worst Method (FBWM) and experts' opinions. And finally, with respect to the outputs of previous phases, the risks were ranked by means of the proposed Z-WASPAS method. In addition to the assignment of different weights to the triple factors and considering the feature of uncertainty in these factors, the proposed approach paid attention to reliability in the risk modes via the Z-Numbers theory. The proposed approach was applied in the operation processes of Mes-e Sarcheshmeh molybdenum factory in Iran and the results indicated a full ranking of risks compared to other conventional methods such as FMEA and fuzzy WASPAS. [ABSTRACT FROM AUTHOR]

The Siah Kamar porphyry Mo deposit is the newly discovered deposit of this type in the Neo Tethys-related Urumieh–Dokhtar magmatic arc, northwest Iran. Mineralization occurs as stock-work quartz–molybdenite and mono-mineralic molybdenite veinlets within the porphyry quartz-monzonite stock and the country rocks, accompanied by locally scattered later-stage and cross-cutting quartz-chalcopyrite-pyrite veinlets in the trachy-andesite and trachy-basalt country rocks. U–Pb zircon geochronology of the porphyry stock yielded Early Oligocene dates of 32.7 ± 0.4 to 30.9 ± 0.4 Ma (at 2σ level). The Th/U ratios of the zircons range between 0.48 and 0.77, and they possess initial εHf(t) values of 3.2 to 12.1, which may suggest a dominant mantle source for the magma. Molybdenite separates yielded rhenium contents between ~10 and 41 ppm (average ~26 ppm, n = 4) and slightly younger Re–Os ages compared to the porphyry stock, ranging from 29.1 ± 0.2 to 28.1 ± 0.2 Ma (at 2σ level). The Siah Kamar porphyry Mo deposit is nearly temporally coeval with the Haft Cheshmeh porphyry Cu deposit and the vein-type Cu–Mo–Au mineralization in the Qarachilar area, corresponding to the second porphyry Cu–Mo mineralization epoch in NW Iran. However, it is younger than the majority of the porphyry Cu deposits in the southern Lesser Caucasus and only shows temporal correlation with the Paragachay and first-stage Kadjaran porphyry Cu deposits. Moreover, it is older than all the porphyry Cu–Mo systems across the central and south-eastern parts of the Urumieh–Dokhtar magmatic arc, except the Bondar Hanza deposit, which is nearly coeval with the Siah Kamar porphyry Mo deposit. All these data reveal an old to young trend along the UDMA and the porphyry Cu belt of Iran, further testifying to the diachronous and later closure of the Neo-Tethyan oceanic basin in central and SE Iran. [ABSTRACT FROM AUTHOR]

The Siah-Kamar porphyry Mo deposit (SKD) is located at the north-western termination of the Urumieh-Dokhtar magmatic arc and it is the only known porphyry Mo ore reserve in Iran. The SKD formed in two main mineralisation stages, at ~33–32 Ma (late-stage, disseminated) and ~ 29–28 Ma (late-stage, high-grade), within a context of a long-lived magmatism. We integrate results from the whole-rock geochemistry, the O C stable and Sr isotope systematics across the mineralised alteration zones with the available drilling data (ore element concentration) to define the ore-forming processes leading to Mo enrichment in the SKD. Our investigation shows that CO 2 bearing magmatic fluids had the major role in both early and late-stage mineralisation. The Mo shows positive correlation with SiO 2 content but a clear negative correlation with W, Cu, and S, due to a delayed precipitation of Mo during the early-stage mineralisation. The released fluids from the new acidic magmas and subsequent fluid-rock interaction in an open-system, primarily assisted by brittle fracturing, and accompanied by cooling and mixing with various amounts of meteoric water and fluid neutralisation, was responsible for the selective ore depletion and Mo-ore enhancement during carbonatisation along structurally-controlled pathways. [Display omitted] • Mo correlates positively with Si, K, Rb, and Pb but negatively with W, Cu, and S. • Two distinct stages of mineralisation (W and Mo) with different fluid conditions. • Existence of a shallow magma chamber with water-saturated acidic melts at ~29 Ma. • Structurally controlled carbonatisation and Mo ore enhancement. • Late carbonate overprinting formed columnar and planar Mo ore bodies. [ABSTRACT FROM AUTHOR]

In this study, we investigated the combined effects of MoS 2 QDs' catalytic properties and the colorimetric responses of organic reagents to create a sniffing device based on the sensor array concept of the mammalian olfactory system. The aim was to differentiate the volatile organic compounds (VOCs) present in cigarette smoke. The designed optical nose device was utilized for the classification of various cigarette VOCs. Unsupervised Principal Component Analysis (PCA) and supervised Linear Discriminant Analysis (LDA) methods were employed for data analysis. The LDA analysis showed promising results, with 100% accuracy in both training and cross-validation. To validate the sensor's performance, we assessed its ability to discriminate between five cigarette brands, achieving 100% accuracy in the training set and 82% in the cross-validation set. Additionally, we focused on studying four popular Iranian cigarette brands (Bahman Kootah, Omega, Montana Gold, and Williams), including fraudulent samples. Impressively, the developed sensor array achieved a perfect 100% accuracy in distinguishing these brands and detecting fraud. We further analyzed a total of 126 cigarette samples, including both original and fraudulent ones, using LDA with a matrix size of (126 × 27). The resulting LDA model demonstrated an accuracy of 98%. Our proposed analytical procedure is characterized by its efficiency, affordability, user-friendliness, and reliability. The selectivity exhibited by the developed sensor array positions it as a valuable tool for differentiating between original and counterfeit cigarettes, thus aiding in border control efforts worldwide.

Groundwater is the main water resource in rural areas throughout the world. The present study aimed to measure nine heavy metals (arsenic, chromium, cobalt, iron, manganese, mercury, molybdenum, nickel, and zinc) in rural areas of Saqqez, Iran. Water samples were collected from 150 sampling stations (wells, springs, and tanks). The heavy metal concentrations were measured using inductively coupled plasma and the spatial distribution of the heavy metal concentrations was mapped. Risk assessment was performed using average daily dose and hazard quotient. The mean concentration of heavy metals in drinking water from different sources were found in order of iron > zinc > chromium > molybdenum > nickel > cobalt > arsenic > mercury > manganese. The concentrations of arsenic, iron, and molybdenum were, however, higher than World Health Organization and U.S. Environmental Protection Agency standards in a few of the samples. Moreover, the statistical analysis revealed that there are no significant variations between well, spring, and tank sources (p < .05). In addition, no significant difference was observed between water quality with different geographical directions and slopes (p < .05). The mean human health risk values for mercury in well and tank water sources were above 1, indicating potential risk. [ABSTRACT FROM AUTHOR]

Heavy metal pollution has become one of the most important threats that can endanger the health of animals, the environment, and humans. The present study was performed to investigate the potential ecological risk (PER) of heavy metals [zinc (Zn), copper (Cu), cobalt (Co), molybdenum (Mo), manganese (Mn), and selenium (Se)] in the coastal soils of southwest Iran in 2019. The samples were collected from six soil sites and three depth intervals (0-15, 15-30, and 30-45 cm) among bare and vegetated coastal soils. The soil samples to study the soil properties (soil grain size, pH, EC, and soil organic carbon) and metal contamination were taken from soil (36 samples), water (6 samples), and plants (24 samples). The soil ecological risk (ER), the pollution load index (PLI), contamination degree (Cdeg), modified contamination degree (mCdeg) for heavy metal contamination in the soil, and enrichment factor (EF index) indicate the origin of metals entering the environment, and hence these parameters were investigated. The results of this study showed that the levels of Zn, Cu, Co, Mn, Se, and Mo were in the range of low-risk contaminants in this region. According to the results of the study, the risk index (RI) for metals was in the range of 1.296-3.845, which is much lower than 150, and therefore the ecological risk potential calculated in this study was in the low-risk category for toxic elements. Based on the results, it was found that agricultural, industrial, and human activities played an effective role in the accumulation of Zn, Cu, Co, Se, and Mo in the soil. In addition, the main source of Mn metal is believed to be natural due to geological activities in the region., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Hamid, Payandeh, Karimi Nezhad and Saadati.)

This paper presents the results of a study on the variation of Re in the Sar Cheshmeh porphyry copper-molybdenum deposit in Iran. The Re content was determined in monomineralic molybdenite separates from veinlets and from molybdenum milled floatation concentrates. Mineralogical data and chemical analyses indicate two generations of veinlet molybdenites in the Sar Cheshmeh deposit. The first generation (molybdenite I), which contains low Re, is found as intergrowth with quartz in silicified rocks with low total sulfide content, and the second generation (molybdenite II), which contains high Re, is found in veinlets with low quartz content. There is a positive correlation between the elevation of molybdenite deposition and Re content. Decrease in the temperature and pH of the hydrothermal fluids are effective for the accumulation Re in molybdenite. X-ray diffraction study of 14 molybdenite samples indicate that the molybdenites are of the 2H polytype. [ABSTRACT FROM AUTHOR]

Abstract: A spent processing catalyst from an Iranian oil refinery was initially characterized physically and chemically. Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans were used to mobilize Al, Co, Mo and Ni from the spent catalysts under optimized conditions in batch cultures. The characteristics of the bioleach solution (pH, Eh, cell concentration and Fe(II)/Fe(III) concentration) were determined along with the concentration of metal values extracted from the catalyst. The results showed that after bioleaching using A. ferrooxidans in the presence of ferrous sulfate, maximum extractions of 63% Al, 96% Co, 84% Mo and 99% Ni were achieved after 30days at pH 1.8–2.0. However, the highest extractions using A. thiooxidans in the presence of sulfur were 2.4% Al, 83% Co, 95% Mo and 16% Ni after 30days at pH 3.9–4.4. The recovery of these metals decreases the environmental impact of the waste catalyst and the recycled product can be further used for industrial purposes. [Copyright &y& Elsevier]

• The interlocking of pyrite with chalcopyrite is the major causes of chalcopyrite access to molybdenum concentrate, • Most of liberated pyrite particles not depressing and have been introduced into molybdenum concentrate, • Molybdenite particles introduced into tailing are blade-shaped and mostly free, • Re-grinding in the flotation circuit, is the major reason for the loss of molybdenite into the flotation tailing. The Sungun copper-molybdenum operation in Iran uses a typical copper-molybdenum flowsheet to produce separate copper and molybdenum concentrates through flotation and regrinding of the rougher concentrates arising from the primary circuit. This site was used as a case study limited to the feed and products of the copper-molybdenum separation circuit, in which process mineralogy might improve the quality of the molybdenum concentrate thorough diagnostic analysis of key flowsheet streams. The undesirable presence of copper in the molybdenum concentrate was identified as a key focus for the investigation by process mineralogy, which has a history of successful process diagnosis. This is because it develops information on minerals, which is far more informative than chemical assays alone. Together with the assays, the mineralogical data inform the investigator of the type and quantity of minerals present, their state of liberation and textural associations, and metal recovery. A key finding was that the appearance of chalcopyrite in the molybdenum concentrate was due to the presence of a chalcopyrite-pyrite texture that avoided the chalcopyrite depression in the molybdenum circuit because of suitable pyrite flotation conditions. Recovery of liberated pyrite to this concentrate also diluted the molybdenum concentrate. The open-circuit format of the regrind circuit also contributed to the unnecessary production of ultrafine particles. This flaw expressed itself as ultrafine losses of molybdenite to the flotation tailings. [ABSTRACT FROM AUTHOR]

Potentially toxic elements (PTE) are considered to be dangerous threats, both for human health and the environment. Here, the contamination level, sources, and ecological risks posed by PTE were investigated in 19 topsoils from agricultural lands in the Bandar Abbas County on the southern coast of Iran. The soil fraction <63 μm was used for the analysis of the pseudototal contents of PTE (arsenic, cadmium, cobalt, chromium, copper, lead, manganese, molybdenum, nickel, vanadium, and zinc). The results were analyzed using principal component analysis (PCA) and Pearson's correlations, different pollution indices [enrichment factor (EF), contamination factor (Cf), and modified degree of contamination (mCd), and the potential ecological risk index (PERI). The results of the pollution indices showed that the contamination levels of the studied agricultural soils are low to moderate, while the average PERI values indicate that the ecological risks of PTE range from low to high in the soils of the studied area. Correlations and PCA analyses suggest that studied elements have three possible origins: geogenic (chromium, cobalt, copper, manganese, vanadium, and zinc), anthropogenic (cadmium, nickel, phosphorus and lead) and atmospheric (arsenic) sources. These findings are helpful for the long-term assessment of PTE in the Bandar Abbas County. [ABSTRACT FROM AUTHOR]

Introduction: Reducing human error is an important factor for enhancing safety protocols in various industries. Hence, analysis of the likelihood of human error in nuclear industries such as radiopharmaceutical production facilities has become more essential., Methods: This cross-sectional descriptive study was conducted to quantify the probability of human errors in a 99 Mo/ 99m Tc generator production facility in Iran. First, through expert interviews, the production process of the 99 Mo/ 99m Tc generator was analyzed using hierarchical task analysis (HTA). The standardized plant analysis risk-human (SPAR-H) method was then applied in order to calculate the probability of human error., Results: Twenty tasks were determined using HTA. All of the eight performance shaping factors (PSF S ) were evaluated for the tasks. The mean probability of human error was 0.320. The highest and the lowest probability of human error in the 99 Mo/ 99m Tc generator production process, related to the 'loading the generator with the molybdenum solution' task and the 'generator elution' task, were 0.858 and 0.059, respectively., Conclusion: Required measures for reducing the human error probability (HEP) were suggested. These measures were derived from the level of PSF S that were evaluated in this study.

The article reports that defying the West, Iran this week vowed to resume research and development on uranium enrichment and other sensitive elements of a nuclear program alleged to include weapons research. But U.S. officials and analysts believe it will take months for Iran to solve a key technical challenge in purifying uranium isotopes--unless it gets outside help. Iran's decision has endangered talks with three European countries on a diplomatic solution to the crisis and has exasperated officials at the International Atomic Energy Agency (IAEA) in Vienna, Austria, which is responsible for verifying that Iran's nuclear program is peaceful. The move also jeopardizes a Russian proposal to allow Iran to carry out uranium enrichment on Russian soil. The world is running out of patience with Iran, IAEA director Mohamed El-Baradei said to Sky News on January 9, 2006. Iran claims that its nuclear program is strictly for producing energy. To that end, it insists on exercising its right under the Nuclear Non-Proliferation Treaty to transform uranium ore, predominantly containing uranium-238, into fuel enriched in the rarer, fissile isotope uranium-235.