Petrochemical Research Articles

Legacy ICS Cybersecurity Assessment Using Hybrid Threat Modeling—An Oil and Gas Sector Case Study

As security breaches are increasingly widely reported in today’s culture, cybersecurity is gaining attention on a global scale. Threat modeling methods (TMM) are a proactive security practice that is essential for pinpointing risks and limiting their impact. This paper proposes a hybrid threat modeling framework based on system-centric, attacker-centric, and risk-centric approaches to identify threats in Operational Technology (OT) applications. OT is made up of software and hardware used to manage, secure, and control industrial control systems (ICS), and its environments include factories, power plants, oil and gas refineries, and pipelines. To visualize the “big picture” of its infrastructure risk profile and improve understanding of the full attack surface, the proposed framework builds on several threat modeling methodologies: PASTA modeling, STRIDE, and attack tree components. Nevertheless, the continuity and stability of vital infrastructure will continue to depend heavily on legacy equipment. Thus, protecting the availability, security, and safety of industrial environments and vital infrastructure from cyberattacks requires operational technology (OT) cybersecurity. The feasibility of the proposed approach is illustrated with a case study from a real oil and gas production plant control system where numerous significant cyberattacks in recent years have targeted OT networks more frequently as hackers realized the possibility of disruption due to insufficient OT security, particularly for outdated systems. The proposed framework achieved better results in detecting threats and severity in the design of the case study system, helping to increase security and support cybersecurity assessment of legacy control systems.

Operational status effect on the seismic risk assessment of oil refineries

The operational status of an oil refinery (type and scale of operations that take place at any time instance) largely determines the amount of fuel produced, circulated within the facility, and stored in tanks. This status is affected by seasonality, periods of peak or low demand, as well as periods of routine maintenance. However, it is an aspect that is typically neglected even though it stands out among the factors that determine the seismic performance of several critical industrial assets, such as the storage tanks, as well as the consequences of any potential failure. An open-source refinery testbed is employed herein to demonstrate the effect of the refinery's operational status on the seismic risk estimates. Alternative realistic operational scenarios are developed following typical industry practices and are arranged over a time period between two refinery major maintenance shutdown events. The most probable damage state is selected for each asset to identify the most vulnerable ones. Based on the type and importance of the impacted assets, the potential consequences are determined at the facility level. Resulting estimates are very different if an earthquake strikes during a regular/high/low-demand period, or a maintenance period. The framework can be utilized to identify the locations within the refinery that may trigger cascading failures and secondary damages, should their assets be damaged by a seismic event. The outcomes can be exploited by stakeholders, risk engineers, and emergency action planners for developing customized and businesslike procedures to enhance the seismic resilience of the facility.

Preparation, characterization, and application of chitosan-silver nanoparticles for Cu(II) and Zn(II) removal from oil refinery wastewater

Copper and zinc stand as one of the most alarming contaminants, presenting a formidable challenge in the realm of drinking water across numerous countries. To deal with this challenge, the sequestration of copper and zinc by adsorption has been extensively investigated in the solid media. Here, an adsorbent system based on a natural polymer - chitosan with physical cross-linking using silver nanoparticles is investigated for high binding, to get a new modified adsorbents (CS/AgNPs) that used these metal ions from simulated oil refinery wastewater. The adsorption mechanism is extensively studied via FTIR, zeta potential, dynamic light scattering (DLS), EDS, SEM, and BET. The prepared adsorbents (CS/AgNPs) have a bigger surface area than pristine chitosan that expanded from 4.74 to 36.34 m2/g, respectively. The prepared CS/AgNPs showed stronger adsorption ability than pristine chitosan attributable to its permeable structure and expanded surface area. In batch experiments, the Langmuir adsorption isotherms revealed that the highest uptake removal amount for Copper (II) and zinc (II) onto CS/AgNPs are 110.67 and 92.13 mg/g, correspondingly. These findings indicate that CS/AgNPs show a great potential as a proficient and selective materials for eliminating copper and zinc ions from aqueous solutions.

An ionic liquid crystal functionalized nanocellulose lubricant additives

Cellulose, one of nature's most abundant, clean, and sustainable resources, has often shown unsatisfactory results when used as bio-lubricant additives. Herein, nanocellulose (NC) from amorphous waste natural poplar was extracted using deep eutectic solvent encapsulation treatment and chlorine bleaching process. Subsequently, 1-hexadecyl-3-methylimidazolium bromide was integrated onto NC using a one-step hydrothermal treatment (high-temperature and high-pressure environment) to obtain ionic liquid crystal (ILC) functionalized products (named as ILC-NC). After ball-milling process and solid phase separation step, ILC-NC exhibits excellent dispersion stability and lubrication properties in the liquid phase (including water and vegetable oil). Based on the polar and colloidal activity properties of ILC, it can form an ordered molecular layer on NC surface and form a lubricating film-like structure, making NC smoother and sliding well. Compared to ILC/NC aqueous dispersion, ILC-NC reduces the coefficient of friction and wear rate on steel disk surface by 68.75 % and 74.07 %, respectively. The minimum coefficient of friction was further reduced to 0.032 as dispersing ILC-NC in sunflower oil, showing a reduction of 0.134 (77.91 %) compared to pure sunflower oil. Finally, the lubrication theoretical model calculation reveals the lubrication state of ILC-NC on the steel disk surface and proposes the lubrication mechanism.

The Preparation of MoS2/Metal Nanocomposites Functionalized with N-Oleoylethanolamine: Application as Lubricant Additives

In this study, MoS2 nanosheets have been prepared and treated ultrasonically with silver ammonia solutions. The MoS2/Ag precursor was reduced using dopamine (DA) as reducing and linking agent at room temperature, and it was subjected to a hydrothermal treatment to produce MoS2/Ag nanocomposites (denoted as MoAg). The MoAg samples were functionalized with N-oleoylethanolamine to improve dispersion in the base oil component of additives. Use of the functionalized MoAg (denoted as Fc-MoAg) as a lubricant additive for steel balls resulted in effective friction reduction and anti-wear. This work avoids ion exchange during exfoliation, and the Ag+ has been reduced to nano-silver particles by dopamine to enlarge the layer spaces of MoS2. Taking the case of lubrication with base oil containing Fc-Mo0.6Ag15, the wear scar diameters and coefficients of friction of the steel balls were 0.428 and 0.098 mm, respectively, which were about three-fifths base oil. In addition, MoS2/Cu and MoS2/Ni nanocomposites were synthesized and the tribological properties associated with steel/steel balls assessed. The results demonstrate that all MoS2/metal composites exhibit enhanced tribological behavior in the steel/steel pair tests. Both nanocomposite synergy and the tribofilm containing sulfide, oxide, carbide, and other compounds play important roles in achieving reduced friction and improved anti-wear. The friction and wear properties of base oil containing Fc-MoAg and commercial additives were evaluated using a four-ball wear tester with steel/steel, steel/zirconia and zirconia/zirconia pairs. The base oil containing Fc-MoAg delivered smaller coefficients of friction (COFs) and/or scarring groove depths than those observed with the use of pure base oil and base oil containing commercial additives.

Research on the corrosion mechanism of Q345R steel under water-oil two-phase flow with the HCl and NH4Cl corrosive medium in low-temperature system of petrochemical plants

The serious corrosion failure phenomenon of HCl and NH4Cl in the water-oil two-phase flow are usually occurred in the low-temperature system of petroleum refinery facilities. In this paper, the corrosion mechanism of these corrosive medium in two-phase flow environment was investigated in detail by using corrosion weight loss, electrochemical measurement methods, surface analysis techniques, and numerical research methods. The results indicate that the corrosion rate of Q345R steel in an HCl-NH4Cl coupling medium falls between the rates observed with each medium alone. The stirring of the corrosive fluid creates an unstable oil-in-water emulsion. The formation of an oil film on the surface of Q345R steel slows down the corrosion process and alters the surface corrosion morphology when the oil phase was not originally present. Increasing the proportion of the water phase accelerates the corrosion rate, and the stronger wettability of the oil phase makes the loose γ-FeOOH products easier to cover the surface, which can effectively prevent the mass transfer and corrosion reaction process.

Adsorption of methylene blue onto clay/carbon composite: kinetics and isotherms study

ABSTRACT Waste treatment for pollution control is a hot topic being studied and has received growing attention. In this study, spent bleaching earth (SBE), a waste material from the oil refineries, was pyrolyzed in a N2 atmosphere to produce an environmentally sustainable clay/carbon composite (SBE@C (500 °C)). SBE@C (500 °C) was tested for its ability to remove methylene blue (MB) from water. The Langmuir model best explained the adsorption isotherms, with maximum adsorption capacity of 29.54 mg/g (MB solution (10–60 mg/L)). The pseudo-second-order kinetic model effectively described the adsorption kinetics data. Thermodynamic parameters indicated spontaneous and endothermic processes. The impact of coexisting cations on MB adsorption by SBE@C (500 °C) decreased in the following order: Fe3+ > Al3+ > Mg2+ > K+ > Na+. The ionic strength results indicated that increasing the concentration of Na+ ions led to a decrease in adsorption capacity. MB removal was greatest at pH level of 8. The adsorption mechanisms involved π–π interactions, electrostatic interactions, and changes in physicochemical properties. After 3 cycles, SBE@C (500 °C) may be recycled up to 11 times before completely losing its adsorption capacity. Overall, SBE@C (500 °C) shows promise for removing MB from wastewater, while mitigating secondary pollution from SBE.

Determination of acoustic properties of paraffin oil mixed with activated coal nanoparticles or SPAN80 using only BAW time delay measurement

An important aspect of controlling the properties of liquids relates to their use in modern engines powered by composite materials. In this context, controlling the properties of industrial fluids containing micro- and nanoscale particles is essential. Understanding the temperature-dependent behavior of fluid density and elasticity is crucial for proper engine operation. Seven physical parameters of pure paraffin oil, paraffin oil with varying concentrations of activated coal nanoparticles or sorbitane monooleate (SPAN 80) were simultaneously determined using only BAW time delay measurement in the single experimental run. This technique relies on propagating LBAW through the test fluid and measuring the time delay and amplitude of these waves at different temperatures. By calculating temperature coefficients for velocity, density, time delay, and expansion using well-established formulas the physical properties of fluids under study were determined. The frequency of the LBAW used in the experiment was 13 MHz. The length of the liquid sample in the propagation direction of LBAW was ∼ 5 mm. The experiments were carried out within a temperature range of −20 °C to +90 °C. The volume of the test sample was around 1 milliliter. The comparison of the physical properties of different suspensions under these conditions allows us to demonstrate the dependence of the measured properties on the type and composition of the medium tested.

The impact of molecular configuration on the bond breaking rates of hydrocarbons: a computational study.

The dissociation of hydrocarbon bonds plays a pivotal role in their utilization, whether through fuel combustion or the thermo-cracking of large hydrocarbons in petroleum refinement. Previous studies have primarily focused on the effects of temperature, pressure, and chemical environment on hydrocarbon reactions. However, the influence of molecular configuration on bond breaking rates has not been thoroughly explored. In this study, we propose an approach to compute bond dissociation rates, and apply it to the reactive molecular dynamics simulation (ReaxFF) trajectories of three molecules: n-tridecane, n-pentane, and 1,3-propanediol. Our results reveal that the bond dissociation rate depends not only on the bond position in the chain, but also on the molecular configuration. Stretched configurations exhibit higher dissociation rates, particularly favoring the breaking of central bonds. Conversely, when the molecule is coiled, resulting in a reduced size, terminal bonds exhibit higher dissociation rates. This research contributes to a deeper understanding of molecular dissociation properties in the oxidation of hydrocarbons, and provides a way to explore the bond breaking properties of other molecules.

Hard turning performance assessment of AISI D2 steel under dual nozzle MQL assisted ZrO2 and GO nano-cutting fluids: A sustainability approach

“Green manufacturing” is often referred as a sustainable manufacturing process where ecofriendly cutting fluids are used to achieve social, economic, and environmental goals, which mitigates the soil, air, and water contamination and enhances operator’s health and safety. In this current study, mineral oil based ZrO2 and GO nano-cutting fluids are utilized for the cooling and lubrication purpose during the machining of hardened AISI D2 steel (55 ± 1 HRC). Machinability characteristics such as tool wear, surface roughness, cutting temperature, power consumption, and the span of the tool has been investigated in this study along with the sustainability aspects such as machining cost, carbon, and noise emissions during the machining process. Machining under GO nano-cutting fluid coupled with dual nozzle assisted MQL outperformed other environments such as ZrO2 NFMQL, pure mineral oil MQL and dry conditions in all aspects. The maximum tool life was achieved under GO NFMQL condition as 136.16 min followed by 94.41, 65.52, 20.58 min under ZrO2 NFMQL, pure oil MQL, and dry conditions. A substantial impact has been noticed on the cost savings under GO-NFMQL condition and cost saving have been reduced by 2.07%, 5.19%, and 5.48%, compared to ZrO2-NFMQL, MQL and dry environments respectively. Further, GO NFMQL environment performed better in both machinability and sustainability aspects than other environments as it gets the highest score of 11 in Pugh matrix sustainability assessment approach.

Detection and quantification of groundnut oil adulteration with machine learning using a comparative approach with NIRS and UV–VIS

Groundnut oil is known as a good source of essential fatty acids which are significant in the physiological development of the human body. It has a distinctive fragrant making it ideal for cooking which contribute to its demand on the market. However, some groundnut oil producers have been suspected to produce groundnut oil by blending it with cheaper oils especially palm olein at different concentrations or by adding groundnut flavor to palm olein. Over the years, there have been several methods to detect adulteration in oils which are time-consuming and expensive. Near infrared (NIR) and ultraviolet–visible (UV–Vis) spectroscopies are cheap and rapid methods for oil adulteration. This present study aimed to apply NIR and UV–Vis in combination with chemometrics to develop models for prediction and quantification of groundnut oil adulteration. Using principal component analysis (PCA) scores, pure and prepared adulterated samples showed overlapping showing similarities between them. Linear discriminant analysis (LDA) models developed from NIR and UV–Vis gave an average cross-validation accuracy of 92.61% and 62.14% respectively for pure groundnut oil and adulterated samples with palm olein at 0, 1, 3, 5, 10, 20, 30, 40 and 50% v/v. With partial least squares regression free fatty acid, color parameters, peroxide and iodine values could be predicted with R2CV’s up to 0.8799 and RMSECV’s lower than 3 ml/100 ml for NIR spectra and R2CV’s up to 0.81 and RMSECV’s lower than 4 ml/100 ml for UV–Vis spectra. NIR spectra produced better models as compared to UV–Vis spectra.

An Analysis Of Energy And Nutrient Content In High Energy Natural Isotonic Drink (Isopower)

Isotonic drink is the carbonated or non-carbonated drink product used to subtitute the fluid lost in the body. Lack of fluid in the body can cause muscle fatigue until causing the performance decrease in athlete. Isotonic drink can accelerate the return of body fluid compared to water. The purpose of this research was to analyze the content of energy, sodium, potassium, and Vitamin C in isotonic drink with raw material coconut water, pure coconut oil, bee bread, palm vinegar, and honey as high energy natural istotonic drink. The research design used was descriptive observation based laboratory test. The data analysis employed SPSS 22 programs namely by carrying out descriptive test until obtained the average for each isotonic namely 247,491 kkla, sodium 77,085 mg.kg, potassium 1000,785 mg/kg and Vitamin C 2,112 mg. This research concluded that the energy drink content has fulfilled the quality specification of isotonic drink, while the sodium and potassium level do not fulfill the quality specification of isotonic drink yet. Likewise with the Vitamin C content which also does not fulfill the Referrence of Nutrition Label namely 10%.

ANALISIS STUDI KOMPARATIF KEBERHASILAN BERWIRAUSAHA PADA PENGUSAHA VCO (VIRGIN COCONUT OIL) DI KABUPATEN BULELENG

This study aims to determine how the analysis of Comparative Studies of Entrepreneurial Success in VCO (Virgin Coconut Oil) Entrepreneurs in Buleleng Regency. This research uses a qualitative approach, with data collection techniques using structured interview techniques to extract information and documentation techniques to collect a number of documents as information data material, namely sound recordings and photographs to make conclusions and data analysis. The source triangulation technique is used as a data validity technique by asking several questions to the sources so that conclusions can be drawn from the answers that have been given. Data analysis techniques used in this study using SWOT analysis, namely strengths, opportunities, weaknesses, and threats. The results of the study analyzed the entrepreneurial success of VCO products in Buleleng Regency from internal and external factors, which is said to be successful is Bali Pure VCO. From the S-O strategy where this strategy uses the strengths of the company, to take advantage of its great opportunities. This can be seen from the situation and condition of the company that is being run, which has followed the development of technology by using large industrial machines and unique packaging techniques and maintained sterilization. In addition, Bali Pure products have also innovated a lot by utilizing coconut fruit not only as pure coconut oil but also as a bath soap product with a variety of natural aromas

1,2,4-trihydroxybenzene induces non-apoptotic cell death via the structural damage of intracellular organelles

Benzene occurs naturally and is widely applied in the production process of petrochemical products. It is mainly exposed through the respiratory tract and dermal and metabolized in the liver, leading to systemic health effects, and 1,2,4-trihydroxybenzene (THB) is a benzene metabolite used as a hair dye ingredient in some countries. In an effort to identify a toxic mechanism of THB, we first analyzed the hair of consumers who used a shampoo containing THB, and contrary to our expectations, THB was not persistent in the hair. Following, we treated THB to human keratinocytes and HeLa Chang liver cells. Membrane damage was observed in both cell lines, which was more notable in HeLa Chang liver cells than in keratinocytes. Thus, we decided on HeLa Chang liver cells as target cells for further study. Cell viability decreased sharply between 20 μg/ml and 40 μg/mL, inducing G2/M phase arrest and non-apoptotic cell death. The expression of carcinogenesis-, DNA damage-, and transcriptional dysregulation–related genes were notably up-regulated, and the structure and function of mitochondria were disrupted. The volume of the ER and acidic compartments decreased, and intracellular ROS and calcium ion levels increased. More interestingly, we found that THB formed unique structures within the cells, especially around the nuclear membrane, and that those structures seemed to dig into the nucleus over time. A reverse docking analysis also showed that SULT1A1, CYP2E1, and CAT, known to play a significant role in protecting cells from harmful factors, might be potential target proteins for THB. Taken together, we suggest that THB induces non-apoptotic cell death via structural damage of intracellular organelles, especially the nuclear membrane.

Crosslinked polyetherimide based electrospun membrane: Effect of fibre morphology on hot oil sorption

Handling hot oil spillage, particularly from oil refineries, petrochemical industry and automobiles is challenging and there have been limited solutions to address the issue. Polyetherimide (PEI) electrospun fibrous membranes were developed in this study by leveraging PEI's high-temperature stability to serve as promising materials for hot oil sorption. The morphology of the membrane forming fibers varied from circular to dumbbell shaped, by judicious choice of solvents of varying boiling points, to study the effect of fiber morphology on oil sorption capacity. Crosslinking of PEI membranes was carried out using ethylenediamine (EDA) to impart structural integrity and resiliency to the membranes. The PEI membrane composed of dumbbell-shaped fibers demonstrated an oil-sorption capacity of 25.4 ±1.5 g/g for engine oil at 150°C within one hour, outperforming a commercial polypropylene (PP) nonwoven absorbent, which failed and collapsed under the same high-temperature conditions. Enhanced oil sorption in the dumbbell-shaped fibrous membrane was achieved due to its lower tortuosity, aligned inter-fiber channels, and higher capillary pressure. Usefulness and sorption capacity of PEI based electrospun membranes may further be explored for controlling the oil spillage through introduction of specific surface features and functionalization.

GA-mADAM-IIoT: A new lightweight threats detection in the industrial IoT via genetic algorithm with attention mechanism and LSTM on multivariate time series sensor data

The Industrial Internet of Things (IIoT) is undergoing rapid development, and as a result, security threats have emerged as a significant concern. IIoT networks, while enhancing service quality, are particularly susceptible to security risks because of their intrinsic interconnectedness and the use of low-power devices. The data produced by millions of sensors in the IIoT is highly dynamic, diverse, and of massive magnitude. The risk of dangers to IoT gadgets in a nuclear plant or a petroleum refinery is significantly greater when compared to that of home appliances. Often connected to the internet, IIoT devices and systems lack robust security measures, rendering them susceptible to cyberattacks. A breach in IIoT security could result in data theft, equipment damage, or even physical harm. To mitigate these risks, IIoT systems require secure authentication and encryption protocols, regular software updates, and proactive monitoring and response capabilities. These methods' primary disadvantages are their difficulty in implementation and inability to ensure effective security. Hence, a second line of protection, such as intrusion threat detection in IIoT, is required. In this research, we propose a new threat intrusion detection model in the IIoT through a genetic algorithm with attention mechanism and modified Adam optimized LSTM (GA-mADAM-IIoT). The GA-mADAM-IIoT consists of six modules: the activity receiver, communication module (CM), attention module (AM), intrusion detection module, mitigation module, and alert module. The GA was designed for feature dimensionality and selection trained on network flow data via a Long Short-Term Memory (LSTM) network. The adaptive moment estimation (Adam) optimizer was modified in order to optimize the LSTM (mADAM-LSTM) networks. To enhance the performance of our model, the categorical cross-entropy (CCE) cost function was used to calculate the difference between the predicted output and the actual output. Additionally, the CCE cost function optimized the model's parameters to minimize the difference between predicted and actual values in terms of probability distributions. The Modified Adam (mADAM) optimization algorithm updates the weights and biases of the LSTM to minimize the cost function. Due to the limited availability of real-world datasets containing accurately labelled anomalies, particularly for industrial facilities and manufacturing facilities, we have utilized two sensor datasets derived from physical test-bed systems for water treatment: Secure Water Treatment (SWaT) and Water Distribution (WADI). In these datasets, operators have simulated attack scenarios that occur in real-world water treatment plants and have recorded these instances as the ground truth anomalies. A regularization parameter was added to the cost function to prevent LSTM from overfitting. In order to improve the model's performance, the AM integrates a succinct yet effective attention mechanism that enhances significant information in the output of the CM. This reduces the burden on GA-mADAM-IIoT to detect threat patterns at the IDS module. The experimental findings showed that the threat detection GA-mADAM-IIoT via GA feature dimensionality and modified Adam LSTM outperforms the ablation studies. Furthermore, we improve the suggested transparency of threat detection by integrating the Shapley Additive Explanations (SHAP) technique from Explainable AI. This enhances the trustworthiness and comprehensibility of the threat detection process. The proposed model was also compared with the state-of-the-art models, and our results showed outstanding accuracy of 99.98 %, AUC of 100 %, recall of 99.98 %, precision of 99.98 %, F1 of 99.98 %, and MCC of 99.66 % on SWaT data. On the WADI, we obtained an accuracy of 99.87 %, AUC of 100 %, recall of 99.87 %, precision of 99.87 %, F1-score of 99.87 %, and MCC of 98.20 %. The proposed GA-mADAM-IIoT is a generalized model that can be integrated with other IIoT security solutions, such as firewalls and access controls, to provide comprehensive security coverage in real time.

DEVELOPMENT OF NEW DESIGNS OF GP TYPE OIL-GAS BURNER DEVICES WITH NITROGEN OXIDES LOW EMISSION FOR OIL REFINERY FURNACES

The article discusses variants for new designs of GP type combined burner devices developed by the authors for oil refinery furnaces in order to reduce harmful emissions of toxic nitrogen oxides as one of the most dangerous chemicals. The main factors influencing the formation of nitrogen oxides during fuel combustion have been established. A classification of burner devices used in tube furnaces at oil refineries is given. Original designs of low-toxicity burner devices of the GP type, protected by patents for utility models differing from existing analogues in novelty and high environmental efficiency are recommended for implementation.

Monoaromatic Compounds Biodegradation by Hydrocarbon-Oxidizing Actinobacteria

Monoaromatic substances belong to the most widespread and dangerous environmental pollutants. They are components of wastewater from oil refineries and the coal and chemical industries and are often found in soil, groundwater, and surface water. The use of actinobacteria for bioremediation of natural and industrial objects contaminated by these substances is an environmentally and economically advantageous alternative to physicochemical cleaning methods. Therefore, it is actual to search for new actinobacteria strains capable to assimilate of monoaromatic compounds for their further use in biotechnologies of purification of the environment polluted by these substances. Aim. To determine the ability of hydrocarbon-oxidizing strains of actinobacteria of the Ukrainian Collection of Microorganisms to assimilate monoaromatic compounds − derivatives of benzene and phenol. Methods. The strain cultivation was carried out in a liquid mineral medium at an initial concentration of monoaromatic compounds of 500 mg/L as the only source of carbon and energy. The expression activity of the catA gene encoding catechol 1,2-dioxygenase, the key enzyme at the initial stage of the monoaromatic compounds biodegradation, was assessed under culture growth conditions with phenol and glucose. Relative expression of the catA gene was evaluated using RT-qPCR. Fatty acid methyl esters were obtained by hydrolysis of cells in a 5 % solution of acetyl chloride in methanol, followed by extraction with an ether-hexane mixture. Methyl esters were identified using an Agilent 6800N/5973 inert GC/MS system (Agilent Technologies, US). Fatty acid content was determined by AgilentChemStation software. Results. It was established that the studied strains of actinobacteria belonging to the species Dietzia maris, Gordonia rubripertincta, Rhodococcus aetherivorans, and Rhodococcus erythropolis differ in their ability to assimilate monocyclic aromatic compounds − benzene and phenol derivatives. Most strains grew better in media with benzene and its derivatives. All strains well grew on a mixture of ethylbenzene, ortho-, meta-, and para-xylene (EX), most of them grew with different intensities on a mixture of benzene, toluene, and ortho-xylene (BTX), and on monosubstrates – benzene, benzotriazole, and benzoate. Toluene was used by 50 % of the studied strains, and only one of them (R. aetherivorans UCM Ac-602) grew on ortho-xylene. A smaller amount of strains grew in media with phenol derivatives. They did not assimilate ortho-cresol and hydroquinone but grew with different intensities on phenol, paranitrophenol, resorcinol, and catechol. Only a few strains grew in the presence of meta- and para-cresols. The widest range of monoaromatic substances was used by R. aetherivorans UCM Ac-602. It was shown that in the process of phenol assimilation by strain R. aetherivorans UCM Ac-602, the level of transcriptional activity of the catA gene encoding the key enzyme of an ortho-pathway of aromatic ring cleavage, catechol 1,2-dioxygenase, increased almost 2-fold after 48 h compared to 24 h of strain growth on this substrate and 3-fold compared to glucose. The obtained data indicate the ability of R. aetherivorans UCM Ac-602 strains to assimilate monoaromatic substances through theortho-cleavage way. During growth on benzene, toluene, BTX and EX substances, the fatty acid pool of cells of this strain was dominated by hexadecanoic C16:0 (32.73-39.81 %), hexadecenoic C16:1 cis-9 (5.66-15.11 %), and octadecenoic C18:1 cis-9 (7.09-11.83 %) acids, as well as 10-methyloctadecanoic 10-Me-C18:0 (29.88-34.76 %) acid. The composition of fatty acids of cells grown on aromatic compounds, unlike those grown on glucose, contained 2.4-4.0 times less unsaturated C18:1 cis-9 acid and 2.8-3.2 times more methyl-branched acid 10Me-C18:0. Conclusions. Assimilation of monoaromatic compounds − derivatives of benzene and phenol - is a strain-specific characteristic of the actinobacteria species. Using strain R. aetherivorans UCM Ac-602 as an example, it was shown that the assimilation of monoaromatic substances in studied actinobacteria occurs through the ortho-cleavage pathway. One of the adaptation mechanisms of strain R. aetherivorans UCM Ac-602 to the assimilation of these substances is a significant decrease in unsaturated fatty acids and an increase in methyl branched acids, which contributes to an increase in membrane rigidity and cell resistance to the toxic effect of these substrates. The data obtained indicate a high level of adaptation of actinobacteria to the assimilation of monoaromatic compounds and the prospects for their further study to be used in biotechnologies for environmental purification from these pollutants.

SEARCH FOR METHODS TO INCREASE THE SEDIMENTATION RATE OF THE UPPER FLOATING LAYER OF OIL SLUDGE PITS

Traditionally, oil sludge with a liquid-viscous consistency is separated into petroleum product, water and solid mechanical impurities. A large number of technological devices, including separators, centrifuges, hydrocyclones of various designs, have been developed to carry out the operation of interfacial separation of liquid-viscous oil sludge.On the territory of every oil refinery that has been in operation for decades, there are oil sludge ponds — natural settling ponds in which large quantities of oil waste accumulate.The problem of processing barn oil sludge in the oil production and refining industry has not yet been completely solved. This is due to the high stability of barn emulsions, the peculiarities of their composition and properties, which are constantly changing under the influence of temperature and various processes occurring in them.The article presents the results of research aimed at identifying the possibility of destruction of a persistent oil-water emulsion taken from the upper floating layer of an oil sludge pit and its preparation without changing the technological scheme and technological parameters.The results of laboratory studies on the destruction of oily liquid during static sedimentation are considered. Simulation of the oily liquid preparation process was carried out in compliance with the temperature and time conditions of operation, with the use of demulsifiers, by analogy with the process of oily liquid preparation, as at the unit. The results of the simulation showed that at the dosage of the demulsifiers used at the unit, even with an increase in the dosage and an increase in the settling time to 5 days, the oil-water emulsion did not collapse at 60 0C. Further studies were carried out by testing eight brands of demulsifiers at different dosages and elevated temperatures. Based on the results of the research and the conclusions made, a scheme for the preparation of oil-containing liquid at static sludge with the existing set of equipment at the unit is proposed.Further studies were carried out to increase the depth and sedimentation rate of the persistent oil-water emulsion.

Study of the Relationship Between Antioxidant Enzymes in the Blood of Women Suffering From Miscarriage and The Effect of Heavy Metal Pollution on Them in Basra, Iraq

In this study, environmental heavy metal pollution is associated with recurrent miscarriage. It is closely linked to oxidative stress and homeostasis imbalance due to reproductive toxicity resulting from (HM), as lead (Pb) and mercury (Hg) are considered among the most important biological factors that are hostile to human health and can reduce the possibility of a healthy pregnancy. This study aimed to investigate the effect of antioxidant enzymes as well as some heavy metals such as lead and mercury on recurrent miscarriage. Comparing them to healthy women with no history of miscarriage. Samples were collected from women who had miscarried, 50 samples, compared to 40 samples from healthy women who had not suffered a miscarriage previously. In Basra Women's and Children's Hospital in Basra, Iraq. During the reproductive age of patients and healthy people (18-40) years. The patients were divided into two groups according to place of residence (city center and countryside). And compare them with healthy women. He also highlighted oxidative stress because it is more affected by heavy metals and the appearance of women who have frequent miscarriages who live in rural areas, where oil and gas refineries are close to them, unlike the city. Due to direct exposed to pollution.