bluuebunny/crossref_metadata_2025_split huggingface dataset:
Green synthesis of novel cyclopentapyridines: One‐pot multicomponent reactions of vinilydene Meldrum's acid
Authors: Amiri Somayeh Soleimani , Azizi Zahra , Hossaini Zinatossadat , Jouladehroodbar Hadi 
Published: June 2024

AbstractThis study focused on the investigation of synthesizing new derivatives of cyclopentapyridines with high yields employing multicomponent reaction that involved vinilydene Meldrum's acid, ethyl 2‐amino‐4‐dioxo‐4‐arylbutanoates, hydrazonoyl chlorides, and activated acetylenic compounds. The reaction was conducted in water at room temperature, resulting in the synthesis of new compounds. Also, the reaction of synthesized cyclopentapyridines with dimethyl acetylenedicarboxylate was performed in water at room temperature which produced other cyclopentapyridine derivatives by elimination of N2. The advantages of this technology encompass rapid response times, high product yields, and facile product separation via uncomplicated procedures.
Photochemical method for preparation of benzo[a]pyrano[3,2‐c]phenazin‐4‐ones from quinoxalines with 4‐pyranone unit
Authors: Tsyganov Dmitry V. , Komogortsev Andrey N. , Melekhina Valeriya G. , Fakhrutdinov Artem N. , Lichitsky Boris V. 
Published: June 2024

AbstractPhotochemical properties of terarylenes with quinoxalines bridge unit and allomaltol fragment was investigated. We have demonstrated that starting compounds with hydroxyl group in 3‐hydroxy‐4‐pyranone substituent does not undergo any photoinduced transformations. Wherein, conversion to methoxy derivatives allows one to realize photochemical 6π‐electrocyclization for considered quinoxalines. Based on data of x‐ray analysis the observed difference in reactivity is connected with the presence of hydrogen bond in hydroxyl derivatives. As a result of carried out research photochemical approach to novel benzo[a]pyrano[3,2‐c]phenazin‐4‐ones was implemented.
Deep Learning‐Enabled Automated Quality Control for Liver MR Elastography: Initial Results
Authors: Nieves‐Vazquez Heriberto A. , Ozkaya Efe , Meinhold Waiman , Geahchan Amine , Bane Octavia , Ueda Jun , Taouli Bachir 
Published: June 2024

BackgroundSeveral factors can impair image quality and reliability of liver magnetic resonance elastography (MRE), such as inadequate driver positioning, insufficient wave propagation and patient‐related factors.PurposeTo report initial results on automatic classification of liver MRE image quality using various deep learning (DL) architectures.Study TypeRetrospective, single center, IRB‐approved human study.PopulationNinety patients (male = 51, mean age 52.8 ± 14.1 years).Field Strengths/Sequences1.5 T and 3 T MRI, 2D GRE, and 2D SE‐EPI.AssessmentThe curated dataset was comprised of 914 slices obtained from 149 MRE exams in 90 patients. Two independent observers examined the confidence map overlaid elastograms (CMOEs) for liver stiffness measurement and assigned a quality score (non‐diagnostic vs. diagnostic) for each slice. Several DL architectures (ResNet18, ResNet34, ResNet50, SqueezeNet, and MobileNetV2) for binary quality classification of individual CMOE slice inputs were evaluated, using an 8‐fold stratified cross‐validation (800 slices) and a test dataset (114 slices). A majority vote ensemble combining the models' predictions of the highest‐performing architecture was evaluated.Statistical TestThe inter‐observer agreement and the agreement between DL models and one observer were assessed using Cohen's unweighted Kappa coefficient. Accuracy, precision, and recall of the cross‐validation and the ensemble were calculated for the test dataset.ResultsThe average accuracy across the eight models trained using each architecture ranged from 0.692 to 0.851 for the test dataset. The ensemble of the best performing architecture (SqueezeNet) yielded an accuracy of 0.921. The inter‐observer agreement was excellent (Kappa 0.896 [95% CI 0.845–0.947]). The agreement between observer 1 and the predictions of each SqueezeNet model was slight to almost perfect (Kappa range: 0.197–0.831) and almost perfect for the ensemble (Kappa: 0.833).ConclusionOur initial study demonstrates an automated DL‐based approach for classifying liver 2D MRE diagnostic quality with an average accuracy of 0.851 (range 0.675–0.921) across the SqueezeNet models.Evidence Level4Technical EfficacyStage 1
Combined application of hot water and hexanal‐based formulations preserves the postharvest quality of mango fruits
Authors: Darshan Devi , Gill Karan Bir Singh , Gill Parmpal Singh , Boora Rajbir Singh , Bajaj Kashish , Gill Mandeep Singh , Singh Harpreet 
Published: June 2024

AbstractBACKGROUNDMango fruits undergo numerous postharvest quality losses during storage. Hence, the present study aimed to increase the shelf life of mango fruits by applying hexanal‐based enhanced freshness formulations (EFF) in combination with hot water treatment (HWT).RESULTSThe findings revealed that, among all the tested applications, the combination of EFF 1.0% + HWT reduced the weight loss, decay incidence, and activity of cell wall degrading enzymes of mango fruits. Also, the combined treatment was effective in maintaining the fruit quality parameters such as soluble solid contents, titratable acidity, ascorbic acid and activity of antioxidant compounds.CONCLUSIONThe present study concludes that the postharvest application of EEF 1.0% in combination with HWT can be used in extending the shelf life of mango cv. ‘Langra,’ fruits stored at 12° C and 85–90% relative humidity for 35 days. © 2024 Society of Chemical Industry.
Radioactivity of Technosols on thermal power station ash disposal sites: Assessment of potential radiological human‐health risk
Authors: Uzarowicz Łukasz , Stobiński Marcin , Jędrzejek Filip , Szarłowicz Katarzyna , Murach Damian 
Published: June 2024

AbstractSoil radioactivity is a poorly recognized form of land degradation; however, there are regions all around the world where it can be dangerous to the environment and human health. The aim of the study was to analyze the radioactivity of Technosols developed on thermal power station (TPS) ash disposal sites. Total concentration of uranium (U), thorium (Th), and cesium (Cs), as well as the radioactivity of select radionuclides in Technosols were determined to recognize the level of radioactivity and to assess the potential radiological health risk. Total U, Th and Cs concentrations in Technosols were in ranges 1.5 to 11.3, 4 to 22.9, and 0.2 to 21.3 mg·kg−1, respectively. The radioisotope activities in Technosols (in Bq·kg−1) were in the 1.6–25.5 (137Cs); 29.2–1265 (40K); 26.2–99.9 (228Th); 27.9–100 (228Ra); 20.5–134. (226Ra); 32.8–177 (210Pb); 23.9–144 (238U); 1.2–7.0 (235U) ranges. The activity concentrations were slightly higher than the activities of non‐contaminated soils. Technosols developed from bituminous coal ash had higher 40K, 228Th, and 228Ra activity concentrations than soils developed from lignite ash. Artificial 137Cs occurred in surface horizons of Technosols due to fall of atmospheric dust enriched in 137Cs. Annual effective dose (AED) in Technosols amounted 0.07–0.16 mSv·a−1 and was somewhat higher than the global and Polish average (0.06 and 0.07 mSv·a−1, respectively) for outdoor external terrestrial radiation. The radioactivity of the investigated Technosols is slightly above the average radioactivity of native soils. The radiological human‐health risk related to the analyzed soils is low.
3D Nanolithography via Holographic Multi‐Focus Metalens
Authors: Wang Xinger , Fan Xuhao , Liu Yuncheng , Xu Ke , Zhou Yining , Zhang Zexu , Chen Fayu , Yu Xuan , Deng Leimin , Gao Hui , Xiong Wei 
Published: June 2024

Abstract3D nanolithography based on two‐photon polymerization (TPP) allows for the high‐precision fabrication of nearly arbitrary 3D micro/nanostructures, finding extensive applications in areas such as micro‐optics, micro‐mechanics, and biomedicine. However, the large size, complexity of optical systems, and high costs have significantly constrained the widespread adoption of 3D nanolithography technology in both scientific research and industry. In this study, a metasurface is introduced, for the first time, into 3D nanolithography resulting in the construction of a miniaturized and simplified TPP system that achieved efficient multi‐focus parallel processing with high uniformity. A microlens array is fabricated, showcasing the system's application capacity to generate an array of devices with high consistency and quality. It is believed that the utilization of metasurface devices will provide a novel TPP operating platform, enabling richer and more flexible printing functionalities while maintaining system miniaturization and low cost.
Ultrathin Niobium‐Doped Indium Oxide Active Layer Enables High‐Performance Phototransistors for Driving Quantum‐Dot Light‐Emitting Diodes
Authors: Lin Jianrong , Fang Wenhui , Tan Haixing , Zhang Haojun , Dai Jingfei , Liu Ziqing , Liu Si , Chen Jianwen , Wu Runfeng , Xu Hua , Ng Kar Wei , Xiao Peng , Liu Baiquan 
Published: June 2024

AbstractActive materials play a crucial role in the performance of phototransistors. However, the discovery of a novel and versatile active material is a big challenge. For the first time, phototransistors with ultrathin niobium‐doped indium oxide (InNbO) active layer are fabricated. The InNbO phototransistors without additional light‐absorbing layers exhibit the performance with a high average mobility of 22.86 cm2 V−1s−1, a turn‐on voltage of −0.75 V, a low sub threshold swing of 0.18 V/decade, and a high on/off current ratio of 5.74 × 108. Detailed studies show that Nb is the key to suppress the free carrier generation due to the strong bonding strength of Nb─O. In addition, the InNbO phototransistors exhibit a very broad spectral responsivity with a photocurrent of 4.72 × 10−4 A, a photosensitivity of 1.69 × 108, and a high detectivity of 3.33 × 1013 Jones under violet (405 nm) light illumination, which is significantly higher than that of the IGZO phototransistors. Furthermore, an active‐matrix quantum‐dot light‐emitting diode pixel circuit based on InNbO phototransistors is demonstrated. The findings not only indicate that InNbO is a new active material for phototransistors, but also suggest that InNbO‐based phototransistors have a great potential for the next‐generation interactive display technology.
All‐Optical Physical Field Recognition Via Sparse Feature Extraction
Authors: Qi Haotong , Hu Jianyang , Li Chang , Zhang Xuyao , Chen Chen , Cao Danlin , Lin Jie , Wang Yiqun , Jin Peng 
Published: June 2024

AbstractOptical computing has been proven to have the ability to process information with ultra‐high speed. Here, an all‐optical feature extraction system via sparse representation (AFE‐SR) is introduced. The AFE‐SR, which is achieved by multiple diffractive optical elements (DOEs), can realize the recognition of generated physical fields with the speed of light. The sparse representation simplifies the target and improves the recognition accuracy. With the mathematical analysis principle of sparse optical features extraction and optical integration, the identification accuracy of the generation of physical fields is 100% in 2100 frames of the experimental videos. The application field of optical computing systems is extended to state recognition.
Reversibility of Semicrystalline Polymers in Creep Testing by Coarse‐Grained Molecular Dynamics Simulations
Authors: Higuchi Yuji , Matsuba Go 
Published: June 2024

AbstractUnraveling the deformation processes of semicrystalline polymers is essential for improving their durability. Owing to their hierarchical structures composed of lamellae and spherulites, many aspects of these deformation processes remain unclear at the molecular scale, such as the differences in molecular structure changes in the elastic and plastic regions and the molecular‐scale structural changes during reversible and irreversible processes. Herein, simulated creep tests of the lamellar structure of polyethylene under a constant load are performed using the coarse‐grained molecular dynamics method. Typical creep curves are observed under various constant loads. During the recovery process after stretching, the reversible and irreversible processes are distinguished by a strain of approximately 0.4 at the boundary of the elastic and plastic regions. Interestingly, during recovery, the interfaces between the amorphous and crystalline layers are highly oriented, which may inhibit strain relaxation. In terms of the molecular structure changes in the plastic region, the number of tie chains remains constant, whereas the numbers of chain ends and loops in the amorphous layers decrease. These simulation results advance current understanding of the molecular‐scale deformation processes of semicrystalline polymers, which contribute to the improvement of long‐term durability and reliability.
Co‐Crystalline Phases of Syndiotactic Polystyrene with Azelaic Acid Molecules of Pharmaceutical Interest
Authors: Covelli Verdiana , Cozzolino Antonietta , Rodriquez Manuela , Daniel Christophe , Rizzo Paola 
Published: June 2024

AbstractSorption of dicarboxylic acid molecules of pharmaceutical interest such as azelaic acid (AzA), in syndiotactic polystyrene (sPS) films presenting δ and ε nanoporous crystalline structure, is reported. Fourier Transform Infrared (FTIR), Polarized FTIR and Wide‐Angle X‐ray diffraction (WAXD) patterns on axially oriented sPS films has been performed to verify their sorption in crystalline lattices resulting in the formation of co‐crystalline (CC) phases. Experimental evidence provides that AzA molecules can be included in the crystalline nanochannels of ε phase both as isolated and hydrogen‐bonded molecules whereas they are only dissolved in the amorphous phase of δ samples.
Melting Behavior of Nanoporous‐Crystalline Poly(2,6‐Dimethyl‐1,4‐Phenylene) Oxide Films
Authors: Nagendra Baku , Salman Syed , Daniel Christophe , Rizzo Paola 
Published: June 2024

AbstractThe melting behavior of nanoporous‐crystalline (NC) poly(2,6‐dimethyl‐1,4‐phenylene)oxide (PPO) films is obtained by guest removal from co‐crystalline (CC) films, as crystallized by sorption at different temperatures of liquid guests exhibiting largely different molecular volumes, is discussed. For all the considered guest‐induced crystallizations, the NC α form is obtained with melting temperatures (Tm) being essentially independent of the chemical nature of the guest. Tm of α NC films, as obtained by solution casting, instead widely varies with guest molecular volume (Tm in the range 236–264°C). This difference in the melting behavior of α NC PPO films is obtained by solution casting and guest‐induced crystallization using the same guest is attributed to the kinetics of the crystallization.
A New FE Modelling Approach to Simulate the Inter‐Layer Adherence in Hybrid Sandwich Structures Achievable by Additive Manufacturing
Authors: Garofano Antonio , Sellitto Andrea , Acanfora Valerio , Battaglia Miriam , Riccio Aniello 
Published: June 2024

AbstractNumerically predicting the mechanical behavior of additively manufactured sandwich structures, particularly those produced through filament extrusion, poses a significant challenge. Existing collapse mechanisms, including interlayer debonding, lack comprehensive numerical formulation. This paper presents an improved finite element (FE) modeling approach for filament‐based additive processes. Utilizing the cohesive zone model (CZM), it incorporates a cohesive‐type contact to simulate critical layer interactions, such as the core‐face sheet interface. Validation against a literature‐referenced composite sandwich structure with designed for additive manufacturing honeycomb core demonstrates good agreement between the proposed numerical approach and experimental test data in compression and bending.
Investigation on the Crashworthiness of a Composite Fuselage Barrel with Double–Double Designed Frames
Authors: Riccio Aniello , Garofano Antonio , Di Caprio Francesco 
Published: June 2024

AbstractDouble–double (DD) laminates approach enables the design of mass‐minimized composite structures with number and orientation of plies tailored on the acting loads. Thus, the investigation of the crashworthiness capabilities is crucial in assessing the airworthiness of DD designed structures. In this work, two composite fuselage barrel configurations with conventional and DD designed frames have been compared to study their crashworthiness performance during an impact event. Numerical results highlight that configurations with DD optimized frames exhibit performance in terms of crashworthiness and passive safety for passengers comparable to the one with conventional designed frames while reducing the structure's total mass by up to 13%.
Structural Evaluation of a Vertical Tail for a Supersonic Vehicle: Architecture, Boundary Conditions, and Material System Influence
Authors: Battaglia Miriam , Baldieri Ferdinando , Russo Gennaro , Voto Claudio , Acanfora Valerio , Sellitto Andrea , Riccio Aniello 
Published: June 2024

AbstractSupersonic aircraft is defined as aircraft that can travel at speeds above the speed of sound (M > 1). For these aircraft, correct dimensioning is essential to enable them to withstand the high aerodynamic loads they face. This study evaluates the impact of internal architecture, boundary conditions, and material on the dimensioning of the vertical tailplane when subjected to a gust load. The optimal configuration is the one that achieves a balance between weight and structural performance. Titanium alloy Ti 6AI‐4 V and carbon/carbon composites are selected as the most suitable materials for this application due to their known high‐temperature resistance. The best configuration, although it weighs 20% times more than the composite configuration, manages to achieve a reduction in tip displacement of 80%, significantly improving strength and instability performance.
Dimensional and Weight Characterization of 3D Printed PET Specimens Designed for Compliant Mechanisms
Authors: Nicolescu Alexandru‐Ionut , Hadăr Anton , Baciu Florin , Stochioiu Constantin , Ulmeanu Mihaela‐Elena 
Published: June 2024

AbstractThe paper presents a study on the dimensional and weight characterization of 3D printed polyethylene terephthalate specimens designed specifically for compliant mechanisms. Compliant mechanisms find applications in various industries, including medical, consumer goods, education, and research and development. Ensuring these mechanisms meet the required functional needs is crucial, particularly when customizing medical devices. The research focuses on material selection, a critical aspect for 3D printed compliant mechanisms. To investigate the influence of the material deposition angle on the quality and precision of 3D printing, the study considers traction and bending specimens. For each specimen type, three sets of five specimens are manufactured, incorporating different deposition angles: 0°, ±45°, and 90°. In total, 30 specimens are produced, labeled, weighted, and measured. The results reveal that specimens printed at a deposition angle of 45° exhibit the smallest dimensional and mass deviations, indicating higher precision and accuracy. Those printed at 0° follow closely in terms of deviation, while specimens printed at 90° display larger deviations.
Numerical Investigation on the Compressive Behaviors of Islamic Geometric Patterns Inspired Architectured Material
Authors: Marcon Stefano , Ferro Paolo , Berto Filippo , Bertolin Chiara , Gao Chao 
Published: June 2024

AbstractThe remarkable mechanical performance of architectural materials—composed of carefully designed building blocks—have received increasing interest from the scientific and engineering community in recent decades. Among architectural materials, lattice materials turned out to be the most promising structure to be further investigated as they offer many attractive properties for engineering applications—e.g., lightweight, auxetic effect, and high strength‐to‐weight ratio. Inspired by traditional Islamic Geometric Patterns (IGPs), this contribution investigates a new set of designs of lattice structures based on geometrical patterns easily controlled by a single designing parameter derived by the “Hasba” (measure in Arabic) method of construction of Islamic geometric patterns. Utilizing the commercial software Abaqus for finite element analysis, the mechanical behavior of an IGP‐inspired lattice structure is numerically analyzed, particularly focusing on its uniaxial in‐plane compressive properties under quasi‐static conditions and revealing, through buckle and postbuckle analyses with a hyperelastic material model, insights into the structural instability and of these innovative lattice structures.
Development of a Prototype Drone through Carbon Fiber Composite Structures and Additive Manufacturing Techniques
Authors: Mihailescu Razvan , Simion Ionel , Enache Catalina Ioana , Chivu Oana Roxana , Nitoi Dan 
Published: June 2024

AbstractDrones, currently employed in various sectors such as the military, agriculture, mapping, and transportation, function as aerial vehicles. This paper highlights contributions related to the construction of a drone with composite structures, utilizing epoxy resin reinforced with carbon fiber. The focus is on designing and practically implementing key structural components, including the main body that supports electronic parts, carbon tube arms, the drone head, and landing bracket. Geometric design is carried out using Inventor 2023 software. Practical aspects encompass the technology employed for crafting drone body elements and details about the materials used. The drone's design undergoes iterative improvements to produce an advanced prototype with superior capabilities compared to existing models. Additive printing is performed using an Anycubic Vyper printer. To ascertain the quality of the new material, tensile and bending tests are conducted to validate the integrity of the composite structures.
Determination of the Friction Coefficient Magnitude in the Case of Polymer Samples Manufactured by 3D Printing
Authors: Crăciun Elisaveta , Mihalache Andrei Marius , Hrițuc Adelina , Coteață Margareta , Dodun Oana , Nagiț Gheorghe , Ionuț Rîpanu Marius , Slătineanu Laurențiu 
Published: June 2024

AbstractIn industrial practice, there are situations where friction processes are developed, one of the components involves in the process being made of polymeric materials. In such situations, it may be necessary to know more information regarding the magnitude of the friction coefficient for polymer–polymer or polymer–metal material pairs. A relatively simple equipment is designed and materialized, starting from the idea of moving a sled on which there is a strip of known material and on which a sample of the material to be tested is pressed with a force of known magnitude. The processing of the results of some experimental tests carried out on this equipment, using specialized software, allows the determination of an empirical mathematical model to highlight the influence exerted by some input factors in the experiment on the size of the friction coefficient. It is thus found that, for the available experimental conditions, the nature of the couple of materials in contact and the thickness of the polymer layer deposited by 3D printing exert the greatest influence on the magnitude of the friction coefficient.