Characterization Methods Research Articles

Characterization of coal pore structures and flow simulation based on CT and experiments of MIP and SEM

Characterization of pore structures and flow simulation are essential to spatial migration of coalbed methane. In this paper, coal samples from Xinjing and Xinzhuang coal mines are collected and a comprehensive characterization method by using computed tomography (CT) technique and experiments of mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) is proposed. Pore structure parameters are finely characterized and analyzed. Moreover, the flow process for coal samples is visualized and flow characteristics are analyzed. The result shows that pore structures of coal samples are strongly heterogeneous and are dominated by micropores, and filled with kaolinite, calcium monofluorophosphate, pyrite, etc. The flow velocity increases obviously in micropores and narrow throats. The flow is greatly affected by the pore structure. This study is of practical significance for the coalbed methane recoverability evaluation and exploration.

Embroidered Transmission Lines with Conductive Yarns: Challenges, Modeling, Fabrication, and Experimental Performance Assessment

This paper presents an enhanced measurement technique for evaluating embroidered transmission lines (TLs), based on a TL characterization method. The evaluation metric is the “pure” losses of the embroidered TL excluding mismatch losses. Enhanced mechanical stability and removability of embroidered samples under a test is supported by a specially designed measurement setup. Losses are used to find the effective conductivity of each embroidery pattern. Various embroidered samples are fabricated, measured, and evaluated. The repeatability of measurements and fabrication are analyzed and assessed, resulting in average deviations of 0.5 dB and 0.7 dB, respectively. A comparative evaluation of two different yarns of low and high conductivity is presented. Single and double stitching patterns for each yarn are manufactured with stitch densities of 1–7 lines/mm. For interconnection with SMA connectors, a conductive fabric contact (CFC) was selected as the finish of the TL, as a more practical interface instead of direct yarn contact (YC). The analysis of the measurements proved useful findings, such as an increase in the stitch density or the amount of yarn used does not always improve the performance; the use of double stitching greatly improves low-performance stitch densities; the effective conductivity of embroidery patterns changes with frequency; the YC interface yields more losses for medium stitch densities, but for higher stich densities, it presents an improved performance compared with the CFC interconnection.

Altering the Solid Electrolyte Interface Through Surface-Modification of Lithium Metal Anode for High-Voltage Lithium Battery

Abstract The physical structure and chemical composition of the solid electrolyte interphase (SEI) affect the performance of the lithium metal anode. The tuning of the chemical composition and structure of the SEI through the surface modification of the lithium metal anode has been conducted. A series of dicarboxylic acids, oxalic acid, malonic acid, succinic acid, glutaric acid, and adipic acid have been utilized to modify the surface of the lithium anode. Physical characterization methods have been employed to study the surface morphology and chemical composition of the SEI. Symmetrical (Li/Li) and asymmetrical (NMC622/Li) cells with pristine lithium and surface modified lithium electrodes have been assembled and tested. NMC622/Li cell with surface modified lithium shows improved performance compared to that of pristine lithium. Malonic acid-treated lithium outperforms all the electrodes by retaining 141 mAh/g specific capacity even after 100 cycles of charge-discharge. XPS depth profiling analysis reveals that the SEI on the MA-Li contains evenly distributed organic and inorganic components which are responsible for the performance of MA-Li.

Application of Polymers as Drug Nanocarriers in the Oral Treatment of Ulcerative Colitis

AbstractUlcerative colitis (UC) is a chronic non‐specific inflammatory disease of the intestines with a high prevalence. Polymer‐prepared nanoparticles are well‐targeted, highly biocompatible, and have high potential for personalized therapy. Polymer nanoparticles are able to achieve localized therapy through their unique design. First, this review compares the advantages and disadvantages of natural and synthetic polymeric materials as well as describes the application of polymeric nanoparticles in UC therapy. Then, the preparation, characterization methods, and current challenges of common polymer nanoparticles are presented. Next, one‐by‐one examples of polymer nanoparticle‐targeted drug delivery strategies for the treatment of UC are presented. In addition, polymer nanoparticle‐based therapeutic approaches for UC, including anti‐inflammatory therapies, reactive oxygen species scavenging therapies, and intestinal flora modulation therapies, are presented. Finally, future research directions for polymer nanoparticles in UC therapy are discussed and current challenges are identified. The aim of this paper is to provide valuable references and guidance for researchers to design and develop novel UC therapies.

Photochemical generation of ketenes from phenanthrene-based cyclobutanones

Various 9,10-cyclopropanated phenanthrenes have been shown previously to be viable photochemical precursors to many different types of carbenes. There is also one known example in the literature of a related approach used to generate diphenylketene from a phenanthrene-derived cyclobutanone in a laser flash photolysis study. In an effort to broaden the scope of this promising yet under-utilized method of ketene generation, the synthesis and characterization of several phenanthrene-based cyclobutanones, and their subsequent photolysis to produce a variety of ketenes, are presented in this report. The ketenes are produced, along with phenanthrene, by a formal 2 + 2 cyclo-reversion of the cyclobutanone moiety and have been intercepted by benzyl alcohol and benzyl amine to form the corresponding benzyl esters and amides respectively.

Laser beam welding of T joints for aluminum–Copper–lithium aircraft panels: Effect of filler wire on recyclability and weldability

This study assessed the weldability and recyclability of four filler wires, two commercial (ER4047 and ER2319) and two experimental (ER2395 and J300), for laser beam welding of aluminum-Copper-lithium (Al–Cu–Li) aircraft panels. The results showed key differences in porosity and crack formation. The ER2319 filler exhibited a higher tendency for wormhole-type porosity compared to the others, which had similar pore area fractions. ER2395 displayed the longest crack length, likely due to its high lithium content. Chemical compatibility with the Al–Cu–Li base alloy AA2198 was confirmed for the ER2319, ER2395, and J300 filler wires, enabling 100% closed-loop recyclability without disassembly or alloy sorting. However, the high silicon content (around 11%) of ER4047 resulted in a recycled alloy that exceeded the allowable Si limit for AA2198, making it unsuitable for closed-loop recycling. Several end-of-life (EoL) strategies were explored for scrap fractions from ER4047-welded coupons. The 0C and 1C cutting strategies yielded hybrid fractions incompatible with AA2198 but suitable for the more Si-tolerant AA2196 alloy. The 3C strategy, involving weld seam separation before remelting, optimized recycling rates and minimized environmental impact. Additionally, a pre-scrap characterization method was developed to analyze weld seam composition, allowing for the prediction of recyclability issues and filler wire mass estimation in coupons where both the skin and stringer were made of the same alloy. This method provides a practical approach for evaluating welded structures in future recycling efforts.

Multi-Electrode Extended Gate Field Effect Transistors Based on Laser-Induced Graphene for the Detection of Vitamin C and SARS-CoV-2.

Despite the clinical data showing the importance of ascorbic acid (AA or vitamin C) in managing viral respiratory infections, biosensors for their simultaneous detection are lacking. To address this need, we developed a portable and wireless device for simultaneous detection of AA and SARS-CoV-2 virus by integrating commercial transistors with printed laser-induced graphene (LIG) as the extended gate. We studied the effect of laser printing pass number and showed that with two laser printing passes (2-pass LIG), the sensor sensitivity and limit of detection (LOD) for AA improved by a factor of 1.6 and 12.8, respectively. Using complementary characterization methods, we attribute the improved response to a balanced interplay of crystallinity, defect density, surface area, surface roughness, pore density and diameter, and mechanical integrity/stability. These factors enhance analyte transport, reduce noise/variability, and ensure consistent sensor performance, making 2-pass LIG the most effective material in this work. Our sensors exhibit promising performance for detecting AA with a selective response in the presence of common salivary interfering molecules, with sensitivity and LOD of 73.67 mV/dec and 54.04 nM in 1× phosphate buffered saline and 81.05 mV/dec and 78.34 nM in artificial saliva, respectively. We also showed that functionalization of the 2-pass LIG gate with S-protein antibody enables the detection of SARS-CoV-2 protein antigens with an ultralow LOD of 52 zg/mL─an improvement of more than 10-fold compared to 1-pass LIG─and 4 particles/mL for virion mimics with a selective response against influenza virus and multiple human coronavirus strains. With low signal drift/hysteresis and wireless capabilities, the developed device holds great potential for improving at-home monitoring and clinical decision-making.

Application of Raman spectroscopy and machine learning for Candida auris identification and characterization.

Currently, combating Candida auris infections and transmission is challenging due to the lack of efficient identification and characterization methods for this species. To address these challenges, our study presents a novel approach that utilizes Raman spectroscopy and artificial intelligence to achieve precise identification and characterization of C. auris at the singe-cell level. It can accurately identify a single cell from the four C. auris clades. Additionally, we developed machine learning models designed to detect antifungal resistance in C. auris cells and differentiate between two distinct phenotypes based on the single-cell Raman spectrum. We also constructed prediction models for detecting aggregating and filamentous cells in C. auris, both of which are closely linked to its virulence. These results underscore the merits of Raman spectroscopy in the identification and characterization of C. auris, promising improved outcomes in the battle against C. auris infections and transmission.

Functionalization of ZnO Nanorods with Au Nanodots via In Situ Reduction for High-Performance Detection of Ethyl Acetate

Ethyl acetate is a critical medical indicator for detecting certain types of cancer. However, at present, available sensitive materials often exhibit drawbacks, such as high operating temperatures and poor responses to low concentrations of ethyl acetate. In this study, a ZnO nanorod sensing material was prepared using high-temperature annealing and a hydrothermally synthesized metal-organic framework (MOF) as a template. Au nanodots (AuNDs) were subsequently modified on the ZnO nanorods using an in situ ion reduction, which provided a better dispersion of Au nanodots compared with that obtained using the common reductant method. A variety of characterization methods indicate that the highly dispersed AuNDs, which possess a high catalytic activity, were loaded onto the surface as active centers, leading to a significant augmentation in the adsorption of oxygen on the surface compared with the original ZnO material. Consequently, the AuND@ZnO material exhibited heightened responsiveness to ethyl acetate at a lower operating temperature. The Au@ZnO-based sensor has a response rate (Ra/Rg) of 41.8 to 20 ppm ethyl acetate gas at 140 °C, marking a 17.4-fold increase compared with that of the original material. Due to its low power consumption and high responsiveness, AuND@ZnO is a promising candidate for the detection of ethyl acetate gas in medical applications.

A Review on the Partitioning of Solutes Along Dislocations and Stacking Faults in Superalloys

AbstractChemical and microstructural alterations at near-atomic scale can influence the high temperature mechanical performance of superalloys. These alterations are strongly associated with solute segregation at crystal defects, such as dislocations and stacking faults. This review provides an overview of the phenomena that occurs during deformation at elevated temperatures due to the interactions of solutes with crystal defects. These interactions are discussed based on investigations conducted by exploiting the recent technological advancements of advanced characterization methods, such as transmission electron microscopy and atom probe tomography. Insights on local phase transformation mechanisms along stacking faults are discussed providing perspectives on new alloy design concepts. Besides, various microstructural alterations controlled by the interactions of solutes with dislocations are discussed. Bringing together observations at near-atomic scale that control superalloys in the macroscopic level, we aim to bridge an atomic scale microanalysis gap. Thus, providing insights that future alloy designers, modelers, and engineers can incorporate these effects into their analyses, alloy design models and life prediction calculations.

MgCo2O4@g‐C3N4 Composite Induced Peroxymonosulfate Activation for Effective Degradation of Tetracycline Under Visible Light

AbstractThe composite Fenton catalyst was prepared by attaching MgCo2O4 to the surface of g‐C3N4 using a one‐pot method after preparing MgCo2O4 through co‐precipitation. The microstructure of the composites was analyzed using X‐ray diffraction (XRD) and other characterization methods. The catalytic activity of the composites towards tetracycline (TC) was studied, and a possible catalytic mechanism was proposed. The experimental results indicate that the degradation of TC by MgCo2O4@g‐C3N4 reached almost 99.0 % within 30 min in the presence of PMS and visible light. The combination of MgCo2O4 and g‐C3N4 improved the absorption of visible light, and the energy level‐matched heterojunction facilitated the separation of photogenerated electrons and holes, accelerating the redox cycle of ≡Co3+/≡Co2+. The free radical quenching experiment confirmed that the main active substances were free radical ⋅O2− and 1O2. The one‐step synthesis of composite catalysts exhibits high catalytic performance and good stability, offering a potential solution for the efficient treatment of tetracycline wastewater.

Advancing Osteoarthritis Treatment: The Therapeutic Potential of Mesenchymal Stem Cell-Derived Exosomes and Biomaterial Integration

Background/Objectives: Osteoarthritis (OA) is a prevalent and debilitating joint disorder characterized by progressive cartilage degradation and inflammation, for which traditional treatments offer only symptomatic relief without halting disease progression. Exosomes, cell-free vesicles derived from mesenchymal stem cells, have emerged as a promising alternative therapy owing to their regenerative and anti-inflammatory properties. Methods: This review synthesizes findings from recent studies (2017–2023) on the therapeutic potential of exosomes in OA treatment, highlighting their ability to modulate the joint microenvironment, reduce inflammation, and promote cartilage repair by delivering bioactive molecules such as cytokines, growth factors, and regulatory ribonucleic acids. Results: We explore the integration of exosomes with biomaterials, such as hydrogels and scaffolds, to enhance their delivery and therapeutic efficacy, and we address the critical challenges associated with their clinical application, including standardization of isolation and characterization methods, scalability of production, mechanistic understanding, and long-term safety. Despite these challenges, exosome-based therapies offer several advantages over traditional and cell-based treatments, including lower immunogenicity, ease of handling, and targeted delivery of therapeutic agents to damaged tissues. Conclusions: We provide an analytical perspective on the current state of exosome research in OA, emphasizing the need for standardized production methods, deeper mechanistic insights, and rigorous long-term safety assessments. Future directions should focus on optimizing delivery systems, exploring personalized medicine approaches, and conducting comparative effectiveness studies to fully realize the potential of exosome therapies for OA treatment. Addressing these gaps will be crucial for translating exosome therapies from bench to bedside and achieving a transformative impact on OA management.

Extraction of RNA from the fungus Moniliophthora Perniciosa (Stahel) Aime and Phillips-Mora cultivated in induction medium for characterization of chitininases

Chitin is considered the second most important biopolymer in nature, both for its physiological functions in different organisms and for its high availability in the biosphere. However, its natural accumulation does not occur in the environment, this demonstrates that there are natural mechanisms responsible for its degradation. The chitinolytic enzymes found in living beings are targets of great biotechnological interest because they degrade chitin into useful derivatives for various sectors of the economy. Given this, this study aimed to extract RNA for subsequent molecular characterization of chitinases from the fungus Moniliophthora perniciosa. To this end, the fungus was cultivated in WY medium, remaining in the greenhouse for 10-14 days. After growth, RNA was extracted using the traditional Trizol method and the Direct-zol commercial kit. The resulting samples were analyzed using the spectrophotometric technique and verified by photodocumentation after agarose electrophoresis. It was observed that the culture medium was considered satisfactory for RNA extraction and the ideal growth time was 8-10 days for the strain to present sufficient mycelial mass for extraction. Furthermore, the commercial kit used was more favorable than the traditional Trizol method, the product had a low level of contaminants and electrophoresis demonstrated high RNA quality due to the presence of intact rRNA bands. Therefore, as it was extracted from cultivation in a medium that induces chitinase production, the RNA extraction described becomes the most suitable method for the molecular characterization of chitinase production.

Functionalized Quasi-Solid-State Electrolytes in Aqueous Zn-Ion Batteries for Flexible Devices: Challenges and Strategies.

The rapid development of wearable and intelligent flexible devices has posed strict requirements for power sources, including excellent mechanical strength, inherent safety, high energy density, and eco-friendliness. Zn-ion batteries with aqueous quasi-solid-state electrolytes (AQSSEs) with various functional groups that contain electronegative atoms (O/N/F) with tunable electron accumulation states are considered as a promising candidate to power the flexible devices and tremendous progress has been achieved in this prospering area. Herein, this review proposes a comprehensive summary of the recent achievements using the AQSSE in flexible devices by focusing on the significance of different functional groups. The fundamentals and challenges of the ZIBs are introduced from a chemical view in the first place. Then, the mechanism behind the stabilization of the flexible ZIBs with the functionalized AQSSE is summarized and explained in detail. Then the recent progress regarding the enhanced electrochemical stability of the ZIBs with the AQSSE is summarized and classified based on the functional groups on the polymer chain. The advanced characterization methods for the AQSSE are briefly introduced in the following sections. Last but not least, current challenges and future perspectives for this promising area are provided from the authors' point of view.

Enhancing Adsorption Performance of Ce(III) by Amine-Thiourea and Aniline-Modified Magnetic Chitosan Nanocomposites.

To enhance the adsorption performance of chitosan for rare earth ions, two novel magnetic chitosan-based adsorbents were prepared by using chitosan-coated magnetic silica nanoparticles modified with amine-thiourea and aniline. The structure of copolymers was analyzed using characterization methods such as X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis, confirming the successful synthesis of modified magnetic chitosan nanocomposites. The investigation explored the influence of pH, contact time, dosage, initial concentration, and temperature on the adsorption performance. Comparative studies revealed a significantly enhanced adsorption performance after modification. The chitosan-coated magnetic silica nanoparticles modified with aniline (PAN-CS/Fe3O4@SiO2) reached adsorption saturation in about 120 min with a capacity of 136 mg/g, while the chitosan-coated magnetic silica nanoparticles modified with amine-thiourea (TSC-CS/Fe3O4@SiO2) exhibited a higher adsorption capacity of 156 mg/g for Ce(III). Both materials demonstrated strong agreement with the Langmuir isotherm model and pseudo-second-order kinetics. Thermodynamic analysis indicated that Ce(III) adsorption is both spontaneous and endothermic. Examination of the adsorption mechanisms suggested that the effective adsorption of Ce(III) is due to the strong synergistic effects of chelation and electrostatic interactions involving amino, carboxyl, and hydroxyl groups. This study demonstrates that chitosan modified with amine-thiourea and aniline is an effective approach to significantly enhance the rare earth ion adsorption by chitosan.

A Comparison of Molecular Techniques for Improving the Methodology in the Laboratory of Pharmacogenetics

One of the most critical goals in healthcare is safe and effective drug therapy, which is directly related to an individual’s response to treatment. Precision medicine can improve drug safety in many scenarios, including polypharmacy, and it requires the development of new genetic characterization methods. In this report, we use real-time PCR, microarray techniques, and mass spectrometry (MALDI-TOF), which allows us to compare them and identify the potential benefits of technological improvements, leading to better quality medical care. These comparative studies, as part of our pharmacogenetic Five-Step Precision Medicine (5SPM) approach, reveal the superiority of mass spectrometry over the other methods analyzed and highlight the importance of updating the laboratory’s pharmacogenetic methodology to identify new variants with clinical impact.

Agent-based modeling system for real-time characterization of film thickness in digital twin coating

In the automated spraying workshop of ship segments, poor visibility caused by dust and fog hampers the effectiveness of the video monitoring system. The traditional method used during the automated spraying process fails to provide real-time measurement of film thickness and prediction of spraying quality, resulting in uneven film thickness and high rework rates. Robotic spraying technology also faces challenges, such as the time-consuming and labor-intensive process of building and computing a highly reliable Computational Fluid Dynamics (CFD) based spraying film-forming simulation model, which cannot be reflected in real-time during the spraying process. The digital twin characterization method, based on the agent model, offers a solution to these limitations and challenges, providing new ideas and approaches for improving and optimizing the spray film formation model. This paper presents the development of a real-time characterization system for sprayed film thickness based on digital twin technology. The spraying film thickness under different working conditions is obtained using Ansys-Fluent simulation software by varying the gun height and gun speed. The predictive model for spraying film thickness is then established using the obtained simulation data and the corresponding gun height and gun speed, employing the surrogate modeling method (BP neural network). The real-time characterization system for spraying film thickness is developed by combining C# and Unity3D. Finally, in order to ensure the accuracy of the predictive model, a spraying experimental platform is built to verify the accuracy of the predictive model.

Harnessing Novel Reduced Graphene Oxide-Based Aerogel for Efficient Organic Contaminant and Heavy Metal Removal in Aqueous Environments

Ensuring clean water sources is pivotal for sustainable development and the well-being of communities worldwide. This study represents a pioneering effort in water purification, exploring an innovative approach utilizing modified reduced graphene oxide (rGO) aerogels. These advanced materials promise to revolutionize environmental remediation efforts, specifically removing organic contaminants from aqueous solutions. The study investigates the exceptional adsorption properties of rGO-aerogel, enhanced with cysteamine, to understand its efficacy in addressing water pollution challenges. The characterization methods utilized encompass various analytical techniques, including FE-SEM, BET, FTIR, TGA, DSC, XPS, NMR, and elemental analysis. These analyses provide valuable insights into the material’s structural modifications and surface chemistry. The research comprehensively explores the intricacies of adsorption kinetics, equilibrium, and isothermal study to unravel the underlying mechanisms governing contaminant removal. MO and Ni2+ exhibited adsorption of 542.6 and 150.6 mg g−1, respectively, at 25 °C. Ni2+ has unveiled the highest removal at pH 5, and MO has shown high removal in a wide pH range (pH 4–7). Both contaminants have shown fast adsorption kinetic performance on an rGO-aerogel surface. This study aims to identify the synergistic effect of cysteamine and rGO in aerogel formation to remove heavy metals and organic contaminants. These findings mark a significant stride in advancing sustainable water-treatment methods and pioneering in synthesizing innovative materials with versatile applications in environmental contexts, offering a potential solution to the global water pollution crisis.

Influence of X-ray spectrum and bowtie filter characterisation on the accuracy of Monte Carlo simulated organ doses: Validation in a whole-body CT scanning mode

PurposeFor patient-specific CT dosimetry, Monte Carlo dose simulations require an accurate description of the CT scanner. However, quantitative spectral information and information on the bowtie filter material and shape from the manufacturer is often not available. In this study, the influence of different X-ray spectra and bowtie filter characterisation methods on simulated CT organ doses is studied. MethodsUsing ImpactMC, organ doses of whole-body CTs were simulated in twenty adult whole-body voxel models, generated from PET/CT examinations previously conducted in these patients. Simulated CT organ doses based on the manufacturer X-ray spectra and bowtie filter data were compared with those obtained using alternative characterisation models, including spectrum generators and experimentally measured dose data. A total of four different X-ray spectra and one bowtie filter model were defined based on these data. ResultsFor all X-ray spectra and bowtie filter combinations, estimated CT organ doses are within 6% from those resulting from simulations with the CT characterisation models provided by the manufacturer. While varying the bowtie filter model results in CT organ dose differences smaller than 1%, dose differences up to 6% are observed when X-ray spectra are not based on the quantitative data from the manufacturer. ConclusionsEstimated organ doses slightly depend on the applied CT characterisation model. When manufacturer’s data are not available, half-value layer and dose measurements provide sufficient input to obtain equivalent X-ray spectra and bowtie filter profiles, respectively.

A single-stranded based library preparation method for virome characterization

BackgroundThe gut virome is an integral component of the gut microbiome, playing a crucial role in maintaining gut health. However, accurately depicting the entire gut virome is challenging due to the inherent diversity of genome types (dsDNA, ssDNA, dsRNA, and ssRNA) and topologies (linear, circular, or fragments), with subsequently biases associated with current sequencing library preparation methods. To overcome these problems and improve reproducibility and comparability across studies, universal or standardized virome sequencing library construction methods are highly needed in the gut virome study.ResultsWe repurposed the ligation-based single-stranded library (SSLR) preparation method for virome studies. We demonstrate that the SSLR method exhibits exceptional efficiency in quantifying viral DNA genomes (both dsDNA and ssDNA) and outperforms existing double-stranded (Nextera) and single-stranded (xGen, MDA + Nextera) library preparation approaches in terms of minimal amplification bias, evenness of coverage, and integrity of assembling viral genomes. The SSLR method can be utilized for the simultaneous library preparation of both DNA and RNA viral genomes. Furthermore, the SSLR method showed its ability to capture highly modified phage genomes, which were often lost using other library preparation approaches.ConclusionWe introduce and improve a fast, simple, and efficient ligation-based single-stranded DNA library preparation for gut virome study. This method is compatible with Illumina sequencing platforms and only requires ligation reagents within 3-h library preparation, which is similar or even better than the advanced library preparation method (xGen). We hope this method can be further optimized, validated, and widely used to make gut virome study more comparable and reproducible.EMStnH64sPQJC5VtA73CKfVideo