Intact Material Research Articles

Mitotic chromatin marking governs asymmetric segregation of DNA damage.

The faithful segregation of intact genetic material and the perpetuation of chromatin states through mitotic cell divisions are pivotal for maintaining cell function and identity across cell generations. However, most exogenous mutagens generate long-lasting DNA lesions that are segregated during mitosis. How this segregation is controlled is unknown. Here, we uncover a mitotic chromatin-marking pathway that governs the segregation of UV-induced damage in human cells. Our mechanistic analyses reveal two layers of control: histone ADP-ribosylation, and the incorporation of newly synthesized histones at UV damage sites, that both prevent local mitotic phosphorylations on histone H3 serine residues. Functionally, this chromatin-marking pathway drives the asymmetric segregation of UV damage in the cell progeny with consequences on daughter cell fate. We propose that this mechanism may help preserve the integrity of stem cell compartments during asymmetric cell divisions.

Fine-Needle Aspiration versus the CytoCore® Motorized Rotating Needle Device for Thyroid Nodule Biopsies: A Retrospective Cohort Study

Introduction: Recently, an FDA cleared motorized fine-needle aspiration device (CytoCore®, Praxis Medical) has become available which is designed to reduce sample variability by enabling more consistent sampling due to the rotational drilling action of the device in combination with the standard in and out motion used to access the thyroid nodule with a needle. The rotation of the needle permits the ability to collect a higher quantity of intact cellular material, which is optimal for determining adequacy and, ultimately, for making a diagnosis. The present study compares the diagnostic performance of a motorized fine needle aspiration (FNA) device to a historical cohort of patients biopsied using ultrasound-guided fine needle aspiration (US-FNA). Methods: Data from 120 patients with thyroid nodules biopsied using a motorized FNA device was retrospectively analyzed. Patient demographics, lesion characteristics, number of passes, Bethesda category, and cellularity scores were compared to a historical control cohort of 100 patients who underwent US-FNA. Nondiagnostic and indeterminate samples rates for motorized FNA were separately compared to literature controls. Results: A significantly reduced median number of passes were required with motorized FNA compared to US-FNA (1.48 ± 0.62 vs. 2.64 ± 1.63, p < 0.001). Adequate samples were obtained after the first pass for 58% of biopsies with motorized FNA compared to 11% with US-FNA. The cumulative percentage of adequate samples increased to 98% after two passes for motorized FNA versus 58% for the US-FNA group. The mean cellularity score was also significantly greater for motorized FNA (3.42 ± 0.63 vs. 1.9 ± 0.59; p < 0.001). A determinant diagnosis was possible for a greater number of samples in the motorized FNA group compared to the control group (91.6% vs. 78%; p = 0.05). The motorized FNA also had a lower nondiagnostic rate compared to US-FNA (2.0% vs. 10%) and a lower indeterminate rate compared to published rates associated with the use of FNA (8.3% vs. 20.0%; p = 0.05). Conclusion: The motorized FNA device required less passes to obtain an adequate biopsy than US-FNA. Its use is also associated with obtaining samples with a higher cellularity and lower nondiagnostic and indeterminate sample rates.

On the Behavior of Bauxite Tailings under a Wide Range of Stresses

Despite its vital importance to the contemporary economy, some drawbacks are mainly associated with waste derived from mining activity. This waste consists of tailings that are hydraulically disposed of in large impoundments, the tailings dams. As the dams are enlarged to accommodate higher amounts of materials, the stress states at which the deposited tailings are submitted change. This may be a concern for the stability of such structures once the geotechnical behavior of this material may be complex and challenging to predict, considering the existing approaches. Thus, the present study concerns the mechanical response of bauxite tailings under a wide span of stresses, ranging from 25 kPa to 4000 kPa. One-dimensional compression tests and isotropically drained and undrained triaxial tests were carried out on intact and remolded samples of the bauxite tailings. The after-shearing grain size distribution was characterized via sedimentation analysis. The results have shown a stress-dependency of the critical state friction angle for the intact material, which may be related to fabric alterations derived from structure deterioration and particle breakage. Overall, this research provides valuable insights into the response of structured and de-structured bauxite tailings, which are helpful for future constitutive modeling of such material.

A phase-field gradient-based energy split for the modeling of brittle fracture under load reversal

In the phase-field modeling of fracture, the search for a physically reasonable and computationally feasible criterion to split the elastic energy density into fractions that may or may not contribute to crack propagation has been the subject of many recent studies. Within this context, we propose an energy split – or energy decomposition – aimed at accurately representing the evolution of a crack under load reversal. To this purpose, two key assumptions are made. First, the damage gradient direction is interpreted as being representative of the normal-to-crack direction, as already assumed in previous works in the literature. The second assumption consists of considering the sign of the projection of the stress tensor onto the damage gradient direction at a point as an indicator of whether this point should behave as an opening or as a closing crack. We associate the latter case (crack closing) to both (a) a complete recovery of elastic energy density of the intact material (i.e., perfectly rough crack surfaces) and (b) a zero crack driving force at that point. The first case (crack opening) is treated classically as a damageable material point at which damage can increase. The implementation of the proposed approach turns out to be remarkably simple and computationally robust. For the evaluation of the displacements and damage gradients at nodes, the classical Z2 technique is used, and a new effective and computationally convenient iterative strategy is implemented to guarantee convergence of the staggered scheme. Four examples are presented in order to assess the suitability of the present model by using both AT1 and AT2 regularization models. Results show the desired effect of limiting crack propagation to prevailing tensile states, as well as of recovering the initial intact stiffness upon load reversal, even when two of the most common energy splits fail.

EBUS-guided cryobiopsy in the diagnosis of mediastinal lesions - step by step

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is the gold standard in the diagnosis of mediastinal and hilar lesions. For certain purposes, such as the diagnosis and subtyping of lymphoproliferative disorders or molecular pathology, a larger amount of intact sample material is required. EBUS cryobiopsy is a new and efficient tool for this purpose. As it is a new approach, there is still no standardised workflow. In this review, we present the procedure step by step as it is performed at the Ruhrlandklinik in Essen.

Post-metabolism impurity profiling of carfentanil, remifentanil, sufentanil, and benzylfentanyl

Carfentanil, remifentanil, and sufentanil are potent fentanyl analogues that are regularly mixed with illicit drugs causing many overdose deaths. Chemical impurity profiling of these drugs is a well-established technique for linking evidence found at a crime scene to other seized samples. The current study aims to expand the application of impurity profiling to metabolized samples to find synthesis specific markers. This is particularly relevant when the drug has been consumed, and no intact material is present at a crime scene. Carfentanil, remifentanil, and sufentanil were synthesized according to the Ugi or 7-step method and benzylfentanyl was produced using the Siegfried method. After in-vitro metabolism with human liver microsomes, the samples were analyzed by gas chromatography-mass spectrometry (GC–MS) and liquid chromatography high resolution tandem mass spectrometry (LC-HRMS/MS). Characteristic markers were found by applying a match criterion approach and principal component analysis (PCA). The precursors 4-ANBP, aniline, and N-phenylacetamide and several metabolites were identified in post-metabolism samples, indicating that specific synthesis information is retained after in-vitro metabolism. The detected levels were in line with concentrations reported in case work. In addition, LDA was applied to maximize discrimination between synthesis methods and to establish likelihood ratios (LRs). Calibrated LR values were in the range of 0.083 to 16 with very low false positive and false negative error rates. In conclusion, the presented work demonstrates the possibility of combining chemical profiling and retrospective biomarker analysis to obtain information about the synthesis method, which could be useful for forensic reconstructions and attribution investigations.

Experimental study of penetration for the analysis of pre-cut free surface parameters in rock materials based on response surface methods

The strength of intact rock material is reduced after it has been cut by techniques such as water jets, based on which the use of disc cutter hobs for rock-breaking by hobbing has good economic results. The kerf is the free surface created by water jet cutting. The kerf depth, kerf spacing, and kerf angle are the main parameters affecting the rock-breaking force of the disc cutter, which can be simplified as the normal penetration load of the indenter. To investigate the effect of prefabricated notch parameters on the penetration load and the sensitivity of the response of penetration load to each factor, response surface tests were carried out on sandstone and granite specimens, and every factor’s impact on the penetration load was examined. The results showed that: (1) The single factor analysis and interactive analysis of the prefabricated kerf parameters for sandstone and granite samples showed that the penetration load was negatively correlated with kerf depth and kerf angle, and positively correlated with kerf spacing within the set range of the test. (2) The difference in rock strength can also affect the penetration load of the samples. In the prefabricated kerf-assisted rock-breaking test, for the high-strength rock samples represented by granite, increasing the prefabricated kerf depth can reduce the penetration load of the samples more effectively.

Characterization of 2-Butanone Peroxide Oligomeric Profiles and Their Associated Gas-Phase and Solution-Phase Rearrangement Products by Electrospray Ionization Mass Spectrometry for Forensic Applications.

2-Butanone peroxide (also known as methyl ethyl ketone peroxide, MEKP) has applications as a cross-linker in the chemical industry and is also encountered as a homemade primary high explosive; therefore, it is of interest to both process chemists and forensic examiners. Specifically for forensic applications, we demonstrate that when traditional synthetic procedures, available to any hobbyist, are utilized to generate MEKP, oligomeric peroxide units (n ≤ 12), along with several other oligomeric byproduct distributions, are readily observed by liquid chromatography-mass spectrometry (LC-MS). These oligomeric byproducts correspond to the formation of methyl/ethyl ketone end group(s) at the oligomer end group (i.e., loss of ethanol(s) and/or methanol(s) from the oligomer termini). Based on the interpretation of the MS and MS/MS behavior along with the characterization of newly generated terminal alkyl ketone products, we propose that these byproducts are consistent with a Hock-like rearrangement of the primary MEKP distribution in the acidified reaction medium. Following a procedure for homemade preparation, triplicate lots were synthesized. Unique oligomeric and byproduct distributions provided discriminatory power between the synthetic lots. Furthermore, the distributions of MEKP oligomers and the various byproducts in the initiated MEKP match the intensity distributions observed in the intact material with remarkable accuracy. This observation suggests that the postinitiation residue of MEKP could be associated or dissociated from a separately collected intact material obtained during an investigation by examining these oligomeric and byproduct profiles.

Physically consistent nonlocal macro–meso-scale damage model for quasi-brittle materials: A unified multiscale perspective

Despite great efforts in capturing the damage evolution law in multiscale approaches in damage mechanics, much less attention has been paid to the conversion from geometric damage to energy dissipation. In the present paper, the newly proposed nonlocal macro–meso-scale damage (NMMD) model is physically consolidated and a multiscale point of view is consistently adopted in both the damage evolution and energy dissipation. In this model, for each macroscopic material point a mesoscopic structure is attached such that all the point pairs composed of this point and the points in its influence domain are connected to it when the material is intact. The deformation field under loading will result in deformation of point pairs, and thus mesoscopic damage related to a point pair will occur if the deformation index of this point pair exceeds the prescribed threshold. Such mesoscopic change among point pairs connected to a material point within its influence domain has two-fold consequences: geometrically the accumulation of mesoscopic damage will result in macroscopic discontinuity, and simultaneously the free energy will be dissipated, leading to degradation of mechanical behavior of quasi-brittle materials. In other words, the damage as a metric of the geometric discontinuity will lead to the damage in the sense of energy dissipation and degradation of mechanical behavior for quasi-brittle materials, which can be physically captured by the ratio of summation of all the dissipated mesoscopic free energy in point pairs to the free energy of intact material within the influence domain. This energy-based macroscopic damage could then be inserted into the framework of continuum damage mechanics. Therefore, the conversion from geometric damage to energetic damage is implemented on the mesoscale instead of the macroscale, and thus a macroscopic energetic degradation function is not needed. In addition, the structured strain which is suitable for quasi-brittle materials can be adopted to determine the deformation index of point pairs. Correspondingly, the macroscopic free energy can be split into dissipative and non-dissipative parts. In this way, several inconsistencies in the previous NMMD models are remedied. The influence of mesoscopic model parameters is investigated in depth, and several numerical examples including mode-I, mixed-mode and compressive splitting fracture problems of quasi-brittle materials are carried out. Numerical results indicate that the proposed model can not only well capture the cracking process with or without initial cracks but also quantitatively predict the load–deformation curves without mesh size sensitivity. Moreover, due to the inherent physical consistency, in mixed-mode cracking problems the proposed model performs better than the previous NMMD model. Problems to be further studied are also discussed.

Damaged creep constitutive models of rock-like materials containing multiple flaws and their relationships to those of the intact materials

A number of pre-flawed specimens made of sandstone-like material with four different numbers and five different angles were prepared and tested in three various loading paths to investigate the time-dependent mechanical behaviors. It was determined that the deformations and strengths increase and decrease with increasing flaw number and decreasing flaw angle, respectively. The ratio of the long-term strength to the uniaxial compressive strength of specimens with the same pre-existing flaws varies within a small range (0.637–0.729). The specimens in the creep tests exhibited more shear failures than those in the uniaxial compression tests. A modified Burgers model was then developed. By using different parameter values, it can well describe the entire creep phases of all the pre-flawed and intact specimens, which is in accordance with the principles of damage mechanics. In view of this, pre-existing flaws were regarded as a type of damage to the intact material, and a damage creep model was developed that can derive the creep curves of fractured materials from those of the intact material. This idea provides a reference for the study of the damage creep model of fractured rock masses.

Simulation of crack propagation in piping components using phase field approach

Understanding the fracture behaviour in pipelines transporting steam and other resources is vital for its longevity and structural integrity. The prediction of crack initiation and propagation, involving crack branching, and the nucleation of new cracks, etc. in fracture processes are challenging tasks. The phase field method (PFM), based on variational formulation, emerged as a competitive mathematical tool to address fracture mechanics problems. PFM does not require the presence of predefined cracks, handles the crack initiation and propagation within the same system. This feature provides an added advantage to PFM and overcomes the limitations of Griffith’s approach-based linear elastic fracture mechanics (LEFM). In the present work, simulation of the crack propagation in the piping components by employing phase field methodologies has been carried out. Two parameters namely; a phase field parameter (ϕ) that varies between 0 and 1 differentiating between broken and intact material, and a length scale parameter (l_0) that approximates the sharp crack into the diffused crack with exponential distribution are introduced in the mathematical modeling. Numerical modeling is solved using the staggered algorithm in three layered scheme defining the displacement field and phase field within a 3-D finite element framework and implemented in Abaqus via user-defined element (UEL) subroutine codes. PFM simulates the crack path and predicts the load-displacement response, which is validated with benchmark problems, and extended for piping components under monotonic loading. The proposed study accurately captures the crack growth behaviour as observed in experiments on SA312 Type 304LN stainless steel pipes and hence, demonstrated the robustness of the proposed formulation.

Albumen and Yolk Plasma Peptidomics for the Identification and Quantitation of Bioactive Molecules and the Quality Control of Hen Egg Products.

Hen eggs and the correspondingfood products are essential components of human diet. In addition to supplying basic nutrients, they contain functional peptides that are released in vivo within the intact raw material following physiological proteolytic events affecting specific proteins or derive from technological processing of albumen and yolk fractions as a result of the dedicated use of proteases from plant and microbial sources. Besides their potential importance for functional applications, peptides released under physiological conditions in intact egg can be used as markers of product storage and deterioration. Therefore, characterization and quantitation of peptides in egg and egg-derived products can be used to implement evaluation of potential bioactivities as well as to assess food product qualitative characteristics. Here, we provide dedicated information on extraction, identification, and quantitative analysis of peptides from albumen and yolk plasma; nano-liquid chromatography-mass spectrometry combined with bioinformatic analysis of resulting raw data by different software tools allowed to assign molecules based on database searching and to evaluate their relative quantity in different samples.

Evaluation of self-healing by a combination of ultrasonic measurements and 3D numerical simulations

Self-healing concrete became an attractive resolution to costly and labour-intensive manual repairs. Up to now, the regain in mechanical performance is generally assessed using destructive tests, which are not suited for in-situ measurements, nor for monitoring purposes. Hence, ultrasound was adopted, combining a non-intrusive character together with a direct correlation to the elastic properties. Ultrasound has shown its potential to evaluate repair and self-healing processes in literature. The wave velocity provides a direct link to the global E-modulus. However, the healing layer cannot be separated from the intact material that is included in the investigated area. Therefore, ultrasonic measurements are combined with 3D numerical wave simulations. Through a comparison between experiments and simulations, an estimation of the elastic properties of the healing layer was performed. Furthermore, a method to evaluate the stiffness and the filling ratio of healed layers within the crack is proposed, based on wave velocity and amplitude.

PSIII-1 Effect of Cannabidiol Extraction on the Cell Wall Carbohydrate Composition of Hemp Inflorescences

Abstract Since the 2018 Farm Bill, US growers have been allowed to cultivate hemp (Cannabis sativa L.), prompting interest in exploring the use of hemp products in ruminant diets. Extraction of cannabidiol (CBD) oil from hemp biomass generates spent inflorescent material that could be upcycled as a feedstuff, yet little is known about its fiber composition. A recent study measured in vitro true digestibility and fermentation parameters of multiple hemp cultivars, some intact and some CBD-extracted (Altman et al., 2022). Both categories of hemp inflorescence material had similar or greater total digestible nutrients (TDN) than an alfalfa cube control, supporting hemp’s potential as a feedstuff. However, comparisons between non-extracted and CBD-extracted samples could not be made, and the fiber content was only described as neutral detergent fiber (NDF). Fiber composition can significantly impact ruminal digestibility, and in-depth characterizations of cell wall carbohydrate composition can provide further insight into the digestibility of a specific plant-based feed. Therefore, in the present study, we examined the effect of CBD oil extraction on the cell wall carbohydrate composition of the inflorescent material of two hemp cultivars. Intact (Biomass) and CBD-extracted (Spent) inflorescent material from two hemp cultivars, Mary and Zelios, were analyzed. The scell wall monosaccharides of the samples were released via two complementary acid hydrolyses, methanolysis and Saeman (sulfuric acid) hydrolysis, and separated and quantified using high-performance anion-exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD). Additionally, the carbohydrate linkage patterns were assessed by generating partially methylated alditol acetates (PMAAs). Student’s unpaired t-tests were run in GraphPad Prism, and no differences (P &amp;gt; 0.05) in monosaccharide concentrations based upon treatment (CBD extraction) or cultivar were found with either hydrolysis method except for the methanolysis glucose concentration between the biomass forms of the two cultivars where Mary Biomass possessed more glucose than Zelios Biomass (P &amp;lt;b0.001). In the Saeman hydrolysates, glucose was the dominant monosaccharide (38.75 ± 1.44 molar %), indicating a large amount of cellulose, supported by the presence of 1,4-Glcp in the linkage analysis. Linkage analysis also revealed the presence of xyloglucans and rhamnogalacturonan Type 1 pectins in all materials. The data showed no effect of CBD oil extraction on the monosaccharide composition, suggesting that the extraction process leaves the fiber components mostly intact, but there may be differences in glucose concentration (and consequently cellulose content) between cultivars of hemp. Future studies may benefit more from investigating the impact of hemp cultivar on fiber digestibility rather than impact of the CBD extraction process.

Modeling heterogeneity and permeability evolution in a compaction band using a phase-field approach

Compaction bands are tabular zones of localized compressive deformation associated with porosity and permeability reduction. Depending on their orientation, compaction bands can act as barriers to fluid flow, and can be detrimental to fluid production in oil and gas reservoirs, as well as in CO2 sequestration. The process of permeability reduction and the development of excess pore pressures during compaction band formation in a heterogeneous rock mass are not fully understood. Furthermore, few studies have modeled compaction band formation considering coupled hydromechanical processes. In this study, we propose a coupled hydromechanical, phase-field approach for capturing the formation and propagation of compaction bands in heterogeneous porous media. Breakage mechanics is adopted to characterize the free energy function in the intact and damaged material. The resulting phase-field variable provides a measure of the degree of grain crushing. Permeability reduction in the zone of compaction localization is modeled using the Kozeny–Carman equation accounting for microstructural evolution. Numerical simulations demonstrate the ability of the model to capture compaction band formation, porosity reduction, and permeability evolution under drained and undrained conditions. The results highlight the role of effective confining pressure, drainage conditions, and material parameters on the styles of compaction bands that form.

A Calcination-Free Sol-Gel Method to Prepare TiO2 -Based Hybrid Semiconductors for Enhanced Visible Light-Driven Hydrogen Production.

Invited for this month's cover are the collaborating groups of Dr. Jianwei Li at the University of Turku and Prof. Chunman Jia, Kang Yang and Dan Wei at Hainan University. The cover image compares the structure of calcined (left) and non-calcined (right) rutile TiO2 doped with a molecule NA. The calcination process enlarges the pores in TiO2 , reducing its surface area and hydrogen production efficiency under visible light. The "sad face" symbolizes the damaged pore structure. Conversely, doping TiO2 with NA without high-temperature calcination forms a covalent bond, resulting in smaller pores, larger surface area, and improved hydrogen production efficiency. The "smiley face" represents the structurally intact TiO2 hybrid material. More information can be found in the Research Article by Jianwei Li, Chunman Jia, and co-workers.

Role of Shear on Strength and Damage Evolution in Soda-Lime Glass Under High Dynamic Pressures

Abstract Silica glasses, such as soda-lime glass (SLG), have found wide ranging applications in engineering due to their excellent optical properties, high strength, and relatively low cost. In such applications, SLG may be subjected to intense dynamic loading due to high/hyper-velocity impact and therefore necessitates understanding of the dynamic shear strength and kinetics for the development of constitutive models. However, while several investigations have generated Hugoniots for silicate glasses, none appear to have measured shearing resistance at pressures above ∼ 20 GPa. In this study, the role of pressure and strain rate on the shearing resistance of soda-lime glass is explored using sandwich configuration high pressure-pressure shear plate impact (HP-PSPI) experiments. These experiments are conducted at pressures ranging from 14 to 42 GPa and strain rates of 105 − 106 s−1, and analyzed using finite element simulations incorporating a modified Johnson–Holmquist (JH-2) material model. The yield strength of SLG is observed to decrease as a function of pressure, which is reminiscent of the evolution of shear strength in granular media at high pressures. This observation suggests a probable shear-induced damage progression from intact material to granular matter in SLG at high pressures.

Elasto-plastic and post-yield weakening jointed rockmass response in a comparison of equivalent-continuum and explicit structural models

The strength and stiffness of a composite rockmass (intact material, defects, joints, bedding, etc.) are primary inputs for the engineering analysis of rock slopes and underground excavations. The Geological Strength Index (GSI) has served rock engineering for three decades as a rockmass assessment system based on the blockiness of the rockmass and discontinuity condition. GSI is used to factor the Hoek–Brown strength envelope for intact rock to represent jointed rockmasses in conventional equivalent-continuum numerical modelling. Modern numerical tools can represent networks of discrete (explicit) structure with assigned discontinuity properties. This provides an opportunity to compare explicit structural modelling with the conventional implicit equivalent-continuum approach. In this paper, explicit structural models are developed using elasto-plastic (constant-strength) constitutive models for intact rock and realistic parametric ranges for explicit structure properties. Explicit model results are compared to equivalent-continuum results, validating the classical implicit approach while also identifying key limitations. Explicit models with post-yield weakening of the intact and structural elements are then developed and compared to post-yield weakening implicit models that use post-yield dilation and empirical relationships between peak and residual GSI. The results provide guidance for practical modelling in strain-weakening rockmasses, including recommendations for post-yield dilation in the traditional implicit approach.

High-resolution core data and machine learning schemes applied to rock facies classification

Abstract This paper presents core analysis practices developed to increase the value of cores in reservoir characterization workflows. Core analysis traditionally implies extensive rock testing programmes that require large numbers of plug samples. Numerous stakeholders compete for intact core material and often do not base sample selection criteria on objective and reliable information. As a consequence, samples dedicated to core analysis programmes consume a significant fraction of the material available, yet they are selected on the basis of very little a priori information and therefore do not necessarily capture the complexity of the targeted formations. In an attempt to change this paradigm, we promote a more integrated core analysis solution combining transdisciplinary, high-resolution, non-destructive measurements on whole cores, for an early yet objective description of cores and the rapid estimation of formation properties. The first section describes multidisciplinary and non-destructive tests designed to increase the value of information from cores while keeping a minimal footprint. Core samples are scanned along a fit-for-purpose surface, with a collection of sensors interfaced to the same table-top equipment. Technologies including ultra-high-resolution pictures, elemental composition and the direct measurements of geomechanical properties provide continuous and high-resolution profiles with a unique depth reference. Panoramic pictures are processed to extract textural and colour features and grain size distributions. Grain size distributions are backed up by analysis of topographical maps created with a laser scan. The results are combined under one unique format, thereby easing interdisciplinary work from the verification of standard tests (routine core analysis, rock mechanical test) to the construction of robust predictive rock models. The paper describes machine learning schemes applied to core datasets. Unsupervised schemes are designed to identify rock facies, while supervised schemes are used to classify tested rocks into predefined rock facies with known petrophysical properties. Case studies highlight the benefits of this approach of core analysis in conjunction with artificial intelligence for the automated identification and classification of rock facies. This novel approach to core analysis leverages a detailed and comprehensive knowledge of the distributions of core properties, available under one unique format for all disciplines, which eases interdisciplinary work and significantly improves existing core analysis standards. It also provides a sound basis to train artificial intelligence rock reservoir property predictors linking well-log data to core-based lithofacies signatures.

Orange peel ash coated Fe3O4 nanoparticles as a magnetically retrievable catalyst for glycolysis and methanolysis of PET waste

Chemical recycling of PET offers the process of recovering virgin grade raw materials that can be reprocessed to produce an intact polymeric material or other valuable products. In the current study, we investigate the advantages of exercising biowaste derived orange peel ash (OPA) magnetic nano-catalyst, OPA@Fe3O4 as a green and reusable heterogeneous solid catalyst for glycolytic and methanolytic degradation of PET waste. The composition and physical features of the prepared catalyst were studied and analyzed using various techniques. Under the optimized condition, the catalyst was able to obtain an excellent bis(2-hydroxyethyl) terephthalate (BHET) and dimethyl terephthalate (DMT) yield with 100% PET conversion. Moreover, the catalyst was able to be recycled for ten consecutive runs for both processes without a significant reduction in the yield of the reaction, addressing the possible implementation of the catalyst for industrial purposes.