Composition Of Products Research Articles

Corrosion behavior and mechanism of Inconel 625 coatings in high-temperature acidic environments for waste incineration applications

This study explores the high-temperature corrosion behavior and mechanisms of laser-clad Inconel 625 coatings applied in waste incineration environments. Inconel 625 coatings were deposited on a substrate using laser cladding technology, and corrosion tests were performed in various high-temperature acidic environments. The coatings were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and laser confocal microscopy to investigate their microstructure, composition, and corrosion products. The findings indicate that corrosion weight gain was most pronounced in HCl environments at 800 °C and HBr environments at 600 °C, underscoring the critical influence of temperature and acidity on reaction kinetics. Moreover, the corrosion morphology was closely tied to the environment, with distinct patterns observed: pitting in HCl, nodular growth in H2SO4, and cracking and spalling in HF and HBr environments. High temperatures promoted oxidation reactions, resulting in the formation of a dense oxide layer predominantly composed of Cr2O3 and NiCr2O4, which offered some degree of protection. However, pitting and cracking in acidic environments suggested that the protective oxide layer's effectiveness was compromised under extreme conditions. This study provides a comprehensive understanding of the corrosion behavior and mechanisms of Inconel 625 coatings in various acidic environments and high temperatures within waste incineration applications. It offers valuable insights into the impact of temperature and different acidic media on corrosion rates and morphologies, laying the groundwork for predicting the service life and developing protective strategies for these materials in industrial settings.

In Vitro Corrosion of Polyester-Coated Magnesium Alloy under pH-Static Conditions.

The resorption rate of bioresorbable implants requires tuning to match the desired field of application. The use of Mg as implant material is highly advantageous, as it provides sufficient mechanical strength combined with its biodegradability. Consequently, the implant vanishes after it has served its intended purpose, allowing the complete restoration of natural tissue and organ function. However, a biodegradable Mg implant requires a biodegradable coating to slow the rate of Mg corrosion, as a permanent coating would negate the benefits of using Mg as an implant material. Therefore, degradable polymers are the materials of choice, especially polyester-based coatings, such as PLLA, as they have been proven in clinical practice over the long term. Within this work, the degradation retarding effect of a physical barrier in form of four clinically relevant polyester-based coatings, poly-l-lactide (PLLA), poly-l-lactide-co-glycolide (PLGA), poly(l-lactide-co-PEG) triblock copolymer (PLLA-co-PEG), and polydioxanone (PDO), is investigated in vitro under pH-static conditions using CO2 gas to compensate pH changes due to Mg corrosion. Coating thicknesses of 7.5 to 8.3 μm were comparable to commercially available stent systems. Quantitative analysis of magnesium concentration in buffered test medium by a photometric assay allows real-time monitoring. Shielding effect of different polyesters through polymer coating and formation of a protective passivation layer beneath the polymer coating was observed and characterized using SEM and EDX techniques. Our finding was that even imperfect polymer layers provide a considerable protective effect, and the used in vitro setup matches reported in vivo observations regarding elemental composition of corrosion products.

Effects of NOx and NH3 on the secondary organic aerosol formation from α-pinene photooxidation

Understanding the effects of mixed anthropogenic pollutants on the photooxidation of volatile organic compounds (VOCs) is essential for unraveling the formation pathways of secondary organic aerosols (SOA). Yet, it remains a highly challenging experimental target owing to the complexities in the precise measurement of molecular compositions of products and number/mass concentrations of particles as a function of pollutant concentration in the ambient atmosphere. Here, a series of well-defined chamber experiments were performed to explore the effects of NOx and NH3 on the SOA formation from photooxidation of the most abundant monoterpene, α-pinene. The results indicate that the suppression effect of NO and NO2 on the α-pinene photooxidation shows monotonous and parabolic trends, respectively. The presence of NH3 enhances particle number concentrations during the α-pinene + NOx photooxidation by participating in reactions with organic acids. New compounds, including organic peroxides, esters, organic nitrates, and peroxyacyl nitrates, are observed at molecular weight (MW) = 166, 173, 217, 231, 280, 282, 304, and 410 through threshold photoionization making use of a recently constructed vacuum ultraviolet free electron laser in positive ion mode. The molecular structures and formation paths of these species are speculated, which advance the category of VOC oxidation products. Our study provides significant understanding of the influence of NOx and NH3 on the VOC photooxidation, which can be utilized to establish predictive SOA formation networks and to improve atmospheric models.

Mechanical properties and strain rate effect of graphene oxide grafted carbon fiber modified concrete under dynamic impact load

In order to improve the shortcomings of carbon fiber, such as smooth surface, poor bonding with concrete matrix and easy to pull out under dynamic impact load, graphene oxide is grafted onto the surface of carbon fiber by chemical bonds to prepare graphene oxide grafted carbon fiber (CF-GO). The dynamic impact test on CF-GO modified concrete (CF-GOMC) is carried out by the split hopkinson pressure bar (SHPB) test system, and the mechanical properties and strain rate effect of CF-GOMC under dynamic impact loads are studied. The modification mechanism of CF-GO is analyzed by microscopic tests. The results show that compared with carbon fiber, the surface roughness and surface area of CF-GO increase and CF-GO is more suitable for bonding with concrete matrix. CF-GO can improve the mechanical properties of concrete under dynamic impact load and enhance the strain rate effect of dynamic mechanical properties indicators by preventing crack, bridging, filling and promoting hydration. With the increase of CF-GO content, the dynamic mechanical properties and strain rate sensitivity of CF-GOMC increase first and then decrease. The optimal content of CF-GO is 0.3 %. The improvement effect of CF-GO on the dynamic mechanical properties and strain rate effect of concrete is better than that of carbon fiber. The graphene oxide on the surface of CF-GO makes the interface of CF-GO/concrete matrix compact by improving the mechanical bite force of fiber/concrete matrix and promoting the formation of hydration products on the surface of fiber. The addition of CF-GO does not change the composition of cement hydration products, but promotes the crystal growth of hydration products and optimizes the pore structure of concrete.

Failure of a high-pressure flash gas pipeline from coal coke gasification to the cleaning section due to hydrogen-induced cracking

ABSTRACT The high-pressure flash pipeline of coal coke gasification leaked within one week after the operation. Further macroscopic observation showed that cracks appeared in the base material area near the weld. The medium transported by the pipe was low-concentration acid gas. Visual inspection, tensile testing, impact testing, chemical composition analysis, metallographic analysis, energy dispersive spectroscopy, X-ray diffraction analysis, and electron backscattering diffraction analysis were used to reveal the sources of cracks in the pipeline. It was found that the cracks were intergranular and filled with corrosion products. The chemical composition of the corrosion products is rich in Cr, S, and O. After the crack was opened, fracture features of ‘rock candy’ were observed, exhibiting brittle fracture characteristics. The cracks were caused by hydrogen-induced cracking along the grain boundary. On this basis, suggestions and countermeasures were put forward for the failure of the high-pressure flash gas pipeline.

Geographical Variation in Pasturelands and Their Impact on the Physicochemical Characterization and Fatty Acid Composition of Cheese in Caraș-Severin County, Romania

In Caraș-Severin County, Romania, the integration of sustainable agricultural practices with organic dairy production represents a unique opportunity to promote agro-tourism farms and guesthouses. This study examines the synergy between the chemical composition of pastures from three farms in different alleys and the impact on the chemical composition of dairy products produced on those farms. Thus, the comparative analysis of two types of traditional cow’s cheeses (soft and mature) from three different areas of Caraș-Severin County was pursued, as well as of the feed given to the animals from which the raw material for obtaining the cheeses originated. Initially, the physicochemical profile of the pastures (fresh grass and grass hay) was analyzed in terms of proximate composition (moisture, lipids, proteins, ash and carbohydrates), and the content of bioactive compounds (total polyphenols, antioxidant activity using the DPPH method). The proximate composition of the cheese samples, including moisture, lipids, proteins, ash and carbohydrates was analysed, and the content of fatty acids. A correlation was also made between the content of bioactive compounds in feed samples and fatty acid profile of the cheese samples. Our findings demonstrate that the geographical area and the chemical composition of the pasture have a considerable influence on the physicochemical characterization and fatty acid composition of the cheese. The cheese from the mountain area had a higher fat, protein and polyunsaturated fatty acid content compared to the samples from the hill and plain areas.

Assessing a single-cell multi-omic analytic platform to characterize ex vivo-engineered T-cell therapy products.

Genetically engineered CD8+ T cells are being explored for the treatment of various cancers. Analytical characterization represents a major challenge in the development of genetically engineered cell therapies, especially assessing the potential off-target editing and product heterogeneity. As conventional sequencing techniques only provide information at the bulk level, they are unable to detect off-target CRISPR translocation or editing events occurring in minor cell subpopulations. In this study, we report the analytical development of a single-cell multi-omics DNA and protein assay to characterize genetically engineered cell products for safety and genotoxicity assessment. We were able to quantify on-target edits, off-target events, and potential translocations at the targeting loci with per-cell granularity, providing important characterization data of the final cell product. Conclusion: A single-cell multi-omics approach provides the resolution required to understand the composition of cellular products and identify critical quality attributes (CQAs).

Understanding normal and restricted normal products in soft directed graphs

This paper extends the framework of soft set theory to directed graphs by introducing and analyzing the concepts of the normal product and restricted normal product of soft directed graphs. Building on Molodtsov’s foundational work in developing soft set theory to address uncertainty in data, this study presents new methods for modeling and understanding complex systems where uncertainty plays a significant role. Soft directed graphs, which enhance traditional graph models by incorporating parameters and uncertain relationships, serve as the foundation for this investigation. The normal product, defined as a combination of two soft directed graphs based on their respective parameter sets, and the restricted normal product, which combines soft directed graphs only where their parameter sets intersect, provide a comprehensive framework for these new operations. This paper also establishes the structural properties of these products, ensuring they are well-defined and retain the key features of soft directed graphs. Furthermore, we derive combinatorial identities related to vertex and arc counts, as well as degree sums, offering deeper insights into the composition and behavior of these graph products.

High-Temperature Steam Oxidation Behavior of VDM Alloy 699 XA Produced by Laser Powder Bed Fusion

AbstractVDM alloy (AM) 699 XA (AM-XA) produced by laser powder bed fusion (LPBF) was subjected to steam oxidation at different high temperatures. Initial studies on mass gain of AM-XA at 650 °C after 500 hours revealed insignificant changes. Typical to high temperatures, a wide range of oxides were obtained at 750 and 950 °C associated with mass gain. To fully understand AM-XA material behavior at high temperatures, hot-rolled 699 XA (HR-XA) was also fabricated and tested under similar conditions. At 750 °C, HR-XA showed a higher mass gain in comparison with AM-XA, whereas at 950 °C mass gain of AM-XA overtook HR-XA. This anomalous behavior was related mostly to carbide formation. In-depth anomalous behavior of AM-XA is explained by investigating the microstructure and phase composition of the oxidation products formed.

Partial substitution of rhodium with ruthenium in Pd-Rh nanoalloys and its impact on catalytic characteristics

In the present work, alumina-supported trimetallic Pd-Rh-Ru catalysts were synthesized and studied in comparison with the bimetallic Pd-Rh reference sample. The alloy nanoparticles were formed on the surface of the alumina support by thermolysis of the complex salts [Rh(NH3)5Cl][Pd(NO2)4] and [Rh(NH3)5Cl]0.5[Ru(NH3)5Cl]0.5[Pd(NO2)4], preliminary deposited via an incipient wet impregnation method. The influence of the conditions of the thermolysis process on the phase composition of the final products and the size of the trimetallic particles was established. Thus, nanoscale trimetallic (Rh-Ru-Pd) alloy particles of a given composition were obtained. The catalytic performance of the alumina-supported samples was examined in a CO oxidation reaction under prompt thermal aging conditions. It was ascertained that the addition of ruthenium only improves both the initial activity and thermal stability of the catalytic system. The state of each metal in the alloy nanoparticles was characterized by diffuse reflectance UV–vis spectroscopy and X-ray photoelectron spectroscopy.

Application of Steady-State and Time-Resolved Fluorescence Spectroscopy in Identification of Bee Products

In this study, steady-state and time-resolved fluorescence spectroscopy techniques have been applied to determine fluorescence characteristics and fluorescence decay kinetics parameters (fluorescence lifetimes and their amplitudes) of available on the Polish market bee products, including several nectar honeys, royal jelly, bee bread in honey and in liquid artificial honey. The fluorescence properties of the tested bee products arise from the presence of a unique composition of aromatic amino acids, vitamins, phenolic compounds and Maillard reaction products. In the 300–550 nm region of the emission spectra (excited at 280 nm), each of the tested bee products exhibited (showed) a specific and distinctive vibronic structure, which was not observed in the spectrum of artificial honey. Quantitative and qualitative composition as well as specific interactions between fluorescent constituents determine the specific fluorescence characteristics of a given bee product providing a unique fingerprint that can be used in the identification of bee products of different botanical origin. Combination of stationary and time-resolved fluorescence techniques seems to be a promising approach in the identification, authentication and quality control of bee products to verify their health-beneficial properties.

Assessment of adeno-associated virus purity by capillary electrophoresis-based western

A rigorous analytical assessment of recombinant adeno-associated virus (rAAV)-based drug products is critical for their successful development as clinical candidates. It is especially important to ascertain high purity while simultaneously ensuring low levels of impurities in the final drug product. One approach to evaluate the purity of rAAV drug products is to determine the relative stoichiometry of the three viral proteins (VPs) that comprise an rAAV capsid, and the levels of impurities in the final drug product. Here we present two capillary electrophoresis-western (CE-western) assays for quantifying (1) the relative stoichiometry of VP using the anti-AAV B1 antibody, and (2) residual levels of a baculovirus protein impurity, GP64, using the anti-GP64 antibody. In each assay, various purified samples from diverse AAV serotypes were analyzed to determine their VP ratio or GP64 levels. The ratio of VP3/VP1 in rAAV samples was correlated with biological activity, and the clearance of GP64 from the manufacturing process was demonstrated. The results obtained from both assays were further supported by liquid chromatography-mass spectrometry analyses. Overall, we report that CE-western is a high-throughput platform that utilizes low sample volumes for a rapid, sensitive, and robust assessment of the identity, composition, and purity of rAAV drug products.

Development of a Technological Flowchart and the Main Components of the Composition of a Cosmetic Product for the Prevention of Inflammatory Skin Diseases (Systematic Scoping Review)

Development of a Technological Flowchart and the Main Components of the Composition of a Cosmetic Product for the Prevention of Inflammatory Skin Diseases (Systematic Scoping Review)

Influence of packing height on the pyrolysis products of Jimsar (China) oil shale

AbstractThe effect of particle packing height (10, 30, 50, 70 mm) on the yield and composition of oil shale pyrolysis products is investigated. The results show that the oil yield could decrease 1.0% and the noncondensable gases yield could increase 0.5% as the oil shale packing height increased from 10 to 70 mm. The main hydrocarbon gases are C1–C6 gases, and the increase of packing bed height could decrease the relative content ratio of alkanes to alkenes in hydrocarbon gases. The primary components of the derived oil are aliphatic compounds, aromatic compounds, and compounds containing heteroatoms in the carbon atoms range of C6–C28. And the hydrogen type of shale oil is mainly composed of methylene groups (about 70%) with longer alkyl chains, and CH3 in aromatics, cycloalkanes, and alkanes. The chemical composition and hydrogen type have certain regularity changes with the changing of packing height, attributing to the effect of temperature gradients between surface and center of packing bed, and the diffusing time of products through the packing bed.

Catalytic pyrolysis of straight-run naphtha to light olefins: Experiment and molecular-level kinetic modeling study

In this work, molecular-level kinetic modeling was developed for the fluid catalytic pyrolysis of straight-run naphtha based on the structural unit and bond-electron matrix framework. The kinetic parameters were tuned and optimized using systematic experimental data from a fluidized bed under different conditions, the predicted values of the fraction yield, naphtha composition, and gas product yield were in agreement with the experimental data. The model can obtain the typical reaction rate of naphtha with different carbon numbers and structure compositions at the molecular level under typical conditions. The model can also quantify and compare the effects of eliminating different side reactions on the light olefins production, and different optimized reaction types of naphtha feedstocks under two typical conditions were revealed, quantitative model calculations show a significant boost in light olefin yield of 15–33 percentage points without hydrogen transfer.

Разработка технологии получения безлактозного молока методом диафильтрации

Abstract. The purpose. The research is aimed at solving the problem related to the development of technology for producing an environmentally friendly product of animal origin – lactose-free milk. This will solve the problem of consumption of milk and dairy products by people who do not tolerate milk sugar for physiological reasons. Analyzing, on the basis of a literary review, the current state of the issue of lactose-free milk production, it can be concluded that existing technologies have certain disadvantages due to changes in the composition of the initial product, or the significant complexity of the technological chain. The proposed development is based on a method of milk diafiltration consisting of several repetitive cycles. The cycle consists in the separation of milk by the ultrafiltration process into permeate (aqueous lactose solution) and concentrate (proteins, fat, lactose residues). Then pure water is added to the concentrate in a volume equal to the volume of the discharged permeate. For a scientifically based approach to the development of the proposed technology, it is necessary to conduct a study of ultrafiltration separation of milk, obtain optimal operating parameters of the process, determine the change in permeability and selectivity of membranes from lactose concentration, consider the possibility of obtaining lactose-free milk with different mass fraction of fat, determine the number of cycles of the membrane diafiltration process. Research methods. The study of the process of ultrafiltration separation of milk was carried out in laboratory conditions on a membrane installation using organic and inorganic membranes. The experiments determined the main characteristics of ultrafiltration membranes – permeability and selectivity, with varying parameters (parameter range: P = 0.15…0.5 MPa, t = 35…65 °C). Results. Based on the experimental data obtained, by processing them and optimizing the parameters, optimal modes of the milk separation process by ultrafiltration were obtained. The following parameters are defined: the velocity of the product in the supramembrane space, the operating pressure of the separation process, its temperature. The preferred ultrafiltration membranes for the membrane-milk system have been selected. Scientific novelty. To develop a technology for producing lactose-free milk, for the first time a number of studies and experiments were carried out, such as changing the permeability and selectivity of membranes from the concentration of lactose, obtaining lactose-free milk with mass fraction of fat the number of cycles of the membrane diafiltration process was determined.

Effect of flowing water on the ettringite-induced healing of concrete cracks by electrodeposition: Experiments and molecular dynamics simulations

The electrodeposition method (EDM) has been regarded as a new technique for healing concrete microcracks in recent years due to its advantages of excellent remediation in aqueous environments. However, a flowing water environment may influence the effectiveness of the EDM. Therefore, in this paper, the effect of flowing water on the synthesis of ettringite by the EDM to heal concrete cracks was investigated through experiments and molecular dynamics simulations. The experiment results showed that the impermeability coefficient of concrete decreased from 6.41 to 5.36 and 5.18 as the flow rate increased from 0 to 1 m/d and 3 m/d after 7d. The healing products on the surface developed from a cotton-like floc structure to a gel-like morphology. At the microscopic level, with the increase in flow rate, the ettringite changed from the disordered distribution of reticulation to the orderly growth of clusters in the form of long rods. Meanwhile, the phase compositions of healing products transformed from ettringite to gypsum and calcium carbonate. In addition, combined with the molecular dynamics simulations by LAMMPS, the increase in flow rate changed the crystal characteristics of the synthesized ettringite, both the decrease in length-to-diameter ratio and crystallinity, as well as the increase in specific surface area, d-spacing, and crystallite size.

Analysis of Operational Control Data and Development of a Predictive Model of the Content of the Target Component in Melting Products

The relevance of this research is due to the need to stabilize the composition of the melting products of copper–nickel sulfide raw materials. Statistical methods of analyzing the historical data of the real technological object and the correlation analysis of process parameters are described. Factors that exert the greatest influence on the main output parameter (the fraction of copper in a matte) and ensure the physical–chemical transformations are revealed: total charge rate, overall blast volume, oxygen content in the blast (degree of oxygen enrichment in the blowing), temperature of exhaust gases in the off-gas duct, temperature of feed in the smelting zone, copper content in the matte. An approach to the processing of real-time data for the development of a mathematical model for control of the melting process is proposed. The stages of processing of the real-time information are considered. The adequacy of the models was assessed by the value of the mean absolute error (MAE) between the calculated and experimental values.

Comprehensive compositional analysis of liquid organic product prepared by industrialized hydrothermal cracking of biomass waste and its potential application as fertilizer

Hydrothermal cracking involves the conversion of organic waste into efficient fertilizer through hydrolysis at temperatures ranging from 180 to 220 °C and pressures of 1.5 to 2.45 MPa, which offers significant advantages in shortening the production cycle, enhancing efficiency, and decomposing antibiotics. As a result, it holds immense practical value for promoting organic fertilizer manufacturing processes globally. The products derived from hydrothermal cracking can be categorized into solid and liquid components. Extensive research has focused on the composition and use of solids, while studies on liquids have mainly examined basic characteristics. The study aimed to comprehensively analyze the components in liquid products prepared through hydrothermal cracking and evaluate their suitability as liquid fertilizers. Specifically, we employed rigorous analytical techniques to accurately identify and quantify medium and trace elements, organic acids, amino acids, and plant growth regulators. Furthermore, we carried out a planting experiment to assess the yield and soil changes following the application of liquid products in maize cultivation. The experimental data revealed that the liquid product contained abundant medium and trace elements, along with 6.22 g/L free amino acids and 9.22 g/L organic acids. It is noteworthy that this liquid product contained 1.22 × 105 pg/mL ABA, 6.26 × 103 pg/mL IAA, 1.07 × 102 pg/mL IBA, and 3.60 × 10−2 pg/mL GA3. The utilization of this liquid product has the potential to enhance the disease resistance of maize crops and promote the accumulation of nitrate nitrogen in the soil. By understanding the composition of liquid products via hydrothermal cracking, valuable insights can be gained into their potential benefits for agricultural and ecological applications.

Impact of dietary regime on the metabolomic profile of bovine buttermilk and whole milk powder

IntroductionBovine milk contains a rich matrix of nutrients such as carbohydrates, fat, protein and various vitamins and minerals, the composition of which is altered by factors including dietary regime.ObjectivesThe objective of this research was to investigate the impact of dietary regime on the metabolite composition of bovine whole milk powder and buttermilk.MethodsBovine whole milk powder and buttermilk samples were obtained from spring-calving cows, consuming one of three diets. Group 1 grazed outdoors on perennial ryegrass which was supplemented with 5% concentrates; group 2 were maintained indoors and consumed a total mixed ration diet; and group 3 consumed a partial mixed ration diet consisting of perennial ryegrass during the day and total mixed ration maintained indoors at night.ResultsMetabolomic analysis of the whole milk powder (N = 27) and buttermilk (N = 29) samples was preformed using liquid chromatography-tandem mass spectrometry, with 504 and 134 metabolites identified in the samples respectively. In whole milk powder samples, a total of 174 metabolites from various compound classes were significantly different across dietary regimes (FDR adjusted p-value ≤ 0.05), including triglycerides, of which 66% had their highest levels in pasture-fed samples. Triglycerides with highest levels in pasture-fed samples were predominantly polyunsaturated with high total carbon number. Regarding buttermilk samples, metabolites significantly different across dietary regimes included phospholipids, sphingomyelins and an acylcarnitine.ConclusionIn conclusion the results reveal a significant impact of a pasture-fed dietary regime on the metabolite composition of bovine dairy products, with a particular impact on lipid compound classes.