bluuebunny/crossref_metadata_2025 huggingface dataset:
Physicochemical, Mechanical, and Esthetic Properties of the Composite Resin Manipulated with Glove Powder and Adhesive as a Modeling Liquid
Authors: Bauer Jose , Mendes Ruan Pinto , Cavaleiro de Macedo Rayssa , Carvalho Edilausson Moreno , Lopes Leonardo , Grazziotin-Soares Renata , Lima Darlon Martins , Oliveira Barbara Costa
Published: November 2022

Composite resins with low flowability are usually handled and manipulated before insertion into the tooth preparation with gloved hands and/or using an instrument covered with a little amount of adhesive to facilitate modeling. We investigated if the modeling techniques (combined or not) affected physicochemical and esthetic properties of a composite resin. Specimens were fabricated and divided into groups according to the handling/modeling technique: Gloved-hands (composite was hand-manipulated with powdered latex gloves); Adhesive (adhesive was used in between the composite layers); Gloved-hands + Adhesive; Control (no adhesive and no touch with gloved-hands). The highest values for flexural strength (MPa), modulus of elasticity (GPa), and fracture toughness (MPa.m0.5) were obtained for Adhesive and Gloved-hands + Adhesive (p < 0.05); the lowest values were obtained for Control and Gloved-hands (p < 0.05). The Control group had the highest sorption. The Gloved-hands (p < 0.05) group had the highest solubility. Adhesive and Gloved-hands + Adhesive had a similar solubility (p > 0.05). The Control group (p < 0.05) had the lowest solubility. There was no statistical interaction between translucency vs. handling/modeling techniques and color stability vs. handling/modeling techniques. Adhesive as a modeling liquid protected the composite against sorption and solubility (if powdered gloves were used) and improved its physical/mechanical properties. Translucency and color stability were not correlated with modeling techniques.
Microstructure and Properties of Densified Gd2O3 Bulk
Authors: Gao Pei-Hu , Jin Can , Zeng Sheng-Cong , Xie Rui-Guang , Zhang Bo , Chen Bai-Yang , Yang Zhong , Guo Yong-Chun , Liang Min-Xian , Li Jian-Ping , Zhang Li-Na , Yan Zhi-Yi , Jia Lu , Zhao Dan
Published: November 2022

In this work, Gd2O3 bulks were sintered at temperatures ranging from 1400 °C to 1600 °C for times from 6 h to 24 h, and their microstructure and properties were studied for a wider application of materials in thermal barrier coatings. The densification of the Gd2O3 bulk reached 96.16% when it was sintered at 1600 °C for 24 h. The elastic modulus, hardness, fracture toughness and thermal conductivity of the bulks all increased with the rise in sintering temperature and extension of sintering time, while the coefficient of thermal expansion decreased. When the Gd2O3 bulk was sintered at 1600 °C for 24 h, it had the greatest elastic modulus, hardness, fracture toughness and thermal conductivity of 201.15 GPa, 9.13 GPa, 15.03 MPa·m0.5 and 2.75 W/(m·k) (at 1100 °C), respectively, as well as the smallest thermal expansion coefficients of 6.69 × 10−6/°C (at 1100 °C).
Dynamics of Strength Gain in Sandy Soil Stabilised with Mixed Binders Evaluated by Elastic P-Waves during Compressive Loading
Authors: Lindh Per , Lemenkova Polina
Published: November 2022

This paper addresses the problem of stabilisation of poor subgrade soil for improving its engineering properties and stiffness. The study aim is to evaluate the effects from single and mixed binders on the gain of strength in sandy soil over the period of curing. We propose an effective non-destructive approach of using P-waves for identifying soil strength upon stabilisation. The growth of strength and stiffness is strongly dependent on time of curing and type of the stabilising agents which can include both single binders and their blended mixtures. The diverse effects from mixed binders on the properties of soil were evaluated, compared and analysed. We performed the experimental trials of five different binders for stabilisation of sandy soil using cement, lime, Ground Granulated Blast Furnace Slag (GGBFS), energy fly ash and bio fly ash. The methodology included soil stabilisation by binders during a total period of 90 days, strength test for the Unconfined Compressive Strength (UCS) and seismic tests on the stabilised samples. The dynamics of soil behaviour stabilised by different binders for days 7, 14, 28 and 90 was statistically analysed and compared. The optimisation of binder blending has been performed using mixture simplex lattice design with three binders in each case as independent variables. Using P-waves naturally exploited strength characteristics of soil samples and allowed us to compare the effects from the individual and blended binders over the complete period of curing with dominating mixes. The results indicate that strength growth in stabilised soil samples is nonlinear in both time and content of binders with dominating effects from slag which contributed the most to the compressive strength development, followed by cement.
Influence of Physical Modification of the Adhesive Composition on the Strength Properties of Aerospace Aluminum Alloy Sheet Adhesive Joints
Authors: Miturska-Barańska Izabela , Rudawska Anna , Doluk Elżbieta
Published: November 2022

One of the most important design factors in the constitution of adhesive joints is the correct choice of adhesive. Currently, there is a full range of options on the commercial market in this regard, but there is increasing research into modifying adhesives for specific engineering applications. The aim of this study was to analyze the effect of physical modification with fillers on the properties of the adhesive composition and the adhesive joints. The adhesives used in the study were a composition of Epidian 5 epoxy resin and PAC curing agent modified with 1% montmorillonite, 5% calcium carbonate and 20% activated carbon. The adhesive compositions in the cured state were subjected to strength tests and SEM and DSC analyses. Using these compositions, adhesive joints of EN AW 2024 T3 aluminum alloy sheets were also made. The tests carried out showed that, due to the use of different fillers, their effects on certain properties of the adhesive compositions are different types. It was shown that physical modification of the adhesive composition does not always result in positive effects. The study also attempted to determine the correlation between the properties of the adhesive compositions in the cured state and the strength of the adhesive joints.
Effect of the Severe Plastic Deformation on the Corrosion Resistance of a Tantalum–Tungsten Alloy
Authors: Ma Guoqiang , Zhao Man , Xiang Song , Zhu Wanquan , Wu Guilin , Mao Xinping
Published: November 2022

Tantalum and its alloys are regarded as equipment construction materials for processing aggressive acidic media due to their excellent properties. In this study, the influence of severe rolling (90%) on the dissolution rate of a cold-rolled Ta-4%W sheet in different directions was investigated during immersion testing and the corresponding mechanism was discussed. The results show that the dissolution rate of the cold-rolled sample is significantly lower than that of the undeformed sample. The corrosion resistance followed the sequence of “initial” < “90%-ND” < “90%-RD” < “90%-TD”, while the strength is in positive correlation with the corrosion resistance. Severe rolling promotes grain subdivision accompanied by long geometrically necessary boundaries and short incidental dislocation boundaries on two scales in the cold-rolled sample. The volume elements enclosed by geometrically necessary boundaries form preferential crystallographic orientations. Such preferential crystallographic orientations can greatly weaken the electrochemical process caused by adjacent volume elements, resulting in greatly reduced corrosion rates in the severely deformed sample. The unexpected finding provides a new idea for tailoring the structures of tantalum alloys to improve both their strength and corrosion resistance.
Hot Deformation Behavior of 4130 High-Strength Steel
Authors: Łukaszek-Sołek Aneta , Śleboda Tomasz , Lisiecki Łukasz , Krawczyk Janusz
Published: November 2022

Hot deformation behavior of 4130 steel and optimization of its processing parameters are presented in this paper. Compression tests were performed at temperatures ranging from 800 to 1200 °C and at the strain rates in the range from 0.01 to 100 s−1. A comprehensive analysis of the material behavior at different temperature and strain-rate ranges was performed taking into account various criteria of stability and instability of the material flow under various thermomechanical conditions. The flow–stress curves obtained during compression tests, as well as the processing maps elaborated on the basis of various flow–stability criteria, are discussed. Processing parameters developed according to the Prasad’s and Murty’s criteria are recommended for designing the technology of forging of the investigated steel. Such parameters ensure the homogeneity and stability of the material flow in a forged part, what was confirmed by successful forging of 4130 steel in industrial conditions. The processing map developed according to Gegel’s approach, as compared to the processing maps obtained in accordance with the Prasad’s and Murty’s criteria, should be treated as general support for determining the thermomechanical processing parameters.
Role of Density and Grain Size on the Electrocaloric Effect in Ba0.90Ca0.10TiO3 Ceramics
Authors: Curecheriu Lavinia , Buscaglia Maria Teresa , Lukacs Vlad Alexandru , Padurariu Leontin , Ciomaga Cristina Elena
Published: November 2022

Pure perovskite Ba0.90Ca0.10TiO3 ceramics, with a relative density of between 79 and 98% and grain sizes larger than 1 µm, were prepared by solid-state reaction. The dielectric and electrocaloric properties were investigated and discussed considering the density and grain size of the samples. Room temperature impedance measurements show good dielectric properties for all ceramics with relative permittivity between 800 and 1100 and losses of <5%. Polarization vs. E loops indicates regular variation with increasing sintering temperature (grain size and density), an increase in loop area, and remanent and saturation polarization (from Psat = 7.2 µC/cm2 to Psat = 16 µC/cm2). The largest electrocaloric effect was 1.67 K for ceramic with GS = 3 µm at 363 K and electrocaloric responsivity (ζ) was 0.56 K mm/kV. These values are larger than in the case of other similar materials; thus, Ba0.90Ca0.10TiO3 ceramics with a density larger than 90% and grain sizes of a few µms are suitable materials for electrocaloric devices.
Effectiveness of Se/ZnO NPs in Enhancing the Antibacterial Activity of Resin-Based Dental Composites
Authors: Saleem Iqra , Rana Nosheen Fatima , Tanweer Tahreem , Arif Wafa , Shafique Iqra , Alotaibi Amenah S. , Almukhlifi Hanadi A. , Alshareef Sohad Abdulkaleg , Menaa Farid
Published: November 2022

Biofilm formation in the resin-composite interface is a major challenge for resin-based dental composites. Using doped z nanoparticles (NPs) to enhance the antibacterial properties of resin composites can be an effective approach to prevent this. The present study focused on the effectiveness of Selenium-doped ZnO (Se/ZnO) NPs as an antibacterial nanofiller in resin composites and their impact on their mechanical properties. Pristine and Se/ZnO NPs were synthesized by the mechanochemical method and confirmed through UV-Vis Spectroscopy, FTIR (Fourier Transform Infrared) analysis, X-ray Diffraction (XRD) crystallography, Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), and Zeta analysis. The resin composites were then modified by varying concentrations of pristine and Se/ZnO NPs. A single species (S. mutans and E. faecalis) and a saliva microcosm model were utilized for antibacterial analysis. Hemolytic assay and compressive strength tests were also performed to test the modified composite resin’s cytotoxicity and mechanical strength. When incorporated into composite resin, 1% Se/ZnO NPs showed higher antibacterial activity, biocompatibility, and higher mechanical strength when compared to composites with 1% ZnO NPs. The Se/ZnO NPs has been explored for the first time as an efficient antibacterial nanofiller for resin composites and showed effectiveness at lower concentrations, and hence can be an effective candidate in preventing secondary caries by limiting biofilm formation.
Analysis of the Effectiveness of Removing Surface Defects by Brushing
Authors: Matuszak Jakub , Zaleski Kazimierz , Ciecieląg Krzysztof , Skoczylas Agnieszka
Published: November 2022

The paper presents the results of a study on the effectiveness of removing surface defects by brushing. Damage to machine components usually begins on their surface or in the surface layer area. This determines the development of methods, conditions, and process parameters that will positively affect the stereometric and physical properties of the surface layer. Experiments were conducted in which surface defects were generated on a specially designed test stand. By controlling the load and speed of the defect generator it was possible to affect the geometry, depth, and width of the surface defect. A FEM simulation of the brushing treatment was carried out in order to determine the effect of fibers passing through a surface defect in the form of a groove with a small depth and width. It was shown that for certain conditions of brushing treatment, surface defects could be removed effectively. Moreover, the microhardness of the surface layer after the brushing process was analyzed. Changes in microhardness due to brushing reached up to 50 μm for EN AW-2024 aluminum alloy and up to 150 μm for AZ91HP magnesium alloy. The results demonstrated that brushing was an effective method for strengthening the surface layer and that the value of strengthening in the area of defects depended on the effectiveness of their removal.
New Ceramic Tiles Produced Using Old Technology Applied on Historic Roofs—Possibilities and Challenges
Authors: Ałykow Krzysztof , Bednarz Łukasz , Piechówka-Mielnik Magdalena , Napiórkowska-Ałykow Magdalena , Krupa Michał
Published: November 2022

In the case of historic buildings, especially those under protection, it is important to replace elements of the roof covering, while maintaining current technical standards, to meet the requirements of the conservator. The authors of the article present alternatives to commonly used solutions, based on their experience with replacing historic building roofing with ceramic tiles made according to the production and firing technology of the nineteenth century. They emphasize that the correct/specialized restoration of existing tiles in a building makes it possible to preserve and reuse them, which is in line with the principles of historic preservation. However, due to the preservation of the roof tiles, it is not always possible to revitalize them. As a solution to the problem, the use of clay roof tiles manufactured according to 19th-century firing technology, including handmade methods, is presented, which preserves the geometry of the historic roof tiles. The approach presented by the authors meets both the requirements of conservation theory and the building standards for roofing elements. Although it is much more expensive than the solutions currently commonly used that result from modern technical requirements and tile-manufacturing technology, in the case of objects of significant cultural heritage, it is a solution that meets modern technical requirements while not compromising the original appearance of the monument.
Microextrusion Printing of Hierarchically Structured Thick V2O5 Film with Independent from Humidity Sensing Response to Benzene
Authors: Gorobtsov Philipp Yu. , Mokrushin Artem S. , Simonenko Tatiana L. , Simonenko Nikolay P. , Simonenko Elizaveta P. , Kuznetsov Nikolay T.
Published: November 2022

The process of V2O5 oxide by the combination of sol-gel technique and hydrothermal treatment using heteroligand [VO(C5H7O2)2–x(C4H9O)x] precursor was studied. Using thermal analysis, X-ray powder diffraction (XRD) and infra-red spectroscopy (IR), it was found that the resulting product was VO2(B), which after calcining at 300 °C (1 h), oxidized to orthorhombic V2O5. Scanning electron microscopy (SEM) results for V2O5 powder showed that it consisted of nanosheets (~50 nm long and ~10 nm thick) assembled in slightly spherical hierarchic structures (diameter ~200 nm). VO2 powder dispersion was used as functional ink for microextrusion printing of oxide film. After calcining the film at 300 °C (30 min), it was found that it oxidized to V2O5, with SEM and atomic force microscopy (AFM) results showing that the film structure retained the hierarchic structure of the powder. Using Kelvin probe force microscopy (KPFM), the work function value for V2O5 film in ambient conditions was calculated (4.81 eV), indicating a high amount of deficiencies in the sample. V2O5 film exhibited selective response upon sensing benzene, with response value invariable under changing humidity. Studies of the electrical conductivity of the film revealed increased resistance due to high film porosity, with conductivity activation energy being 0.26 eV.
Non-Destructive Health Monitoring of Structural Polymer Composites: Trends and Perspectives in the Digital Era
Authors: Chaki Salim , Krawczak Patricia
Published: November 2022

Non-destructive testing (NDT) techniques are usually used for the characterisation of defects arising in polymer composites during manufacturing or in-service use. However, each of these NDT techniques cannot always allow a full diagnosis of the material’s or component’s structural health. Thus, several techniques have to be combined in order to improve the diagnosis of the damaged state of composite structures and their evolution during the part’s life span. This opinion paper proposes a critical overview of the use and applicability of these NDT techniques for the detection and characterisation of damage to structural composite materials in view of in-service performance assessment and residual durability prognosis. It also addresses some current trends of structural health monitoring (SHM) of these materials, such as sensor–actuator embedding and NDT data fusion, and draws future perspectives on how composite SHM could evolve in the digital era, taking advantage of artificial intelligence, Internet of Things and big data to implement digital twins.
A GAN-BPNN-Based Surface Roughness Measurement Method for Robotic Grinding
Authors: Zhang Guojun , Liu Changyuan , Min Kang , Liu Hong , Ni Fenglei
Published: November 2022

Existing machine vision-based roughness measurement methods cannot accurately measure the roughness of free-form surfaces (with large curvature variations). To overcome this problem, this paper proposes a roughness measurement method based on a generative adversarial network (GAN) and a BP neural network. Firstly, this method takes images and curvature of free-form surfaces as training samples. Then, GAN is trained for roughness measurement through each game between generator and discriminant network by using real samples and pseudosamples (from generator). Finally, the BP neural network maps the image discriminant value of GAN and radius of curvature into roughness value (Ra). Our proposed method automatically learns the features in the image by GAN, omitting the independent feature extraction step, and improves the measurement accuracy by BP neural network. The experiments show that the accuracy of the proposed roughness measurement method can measure free-form surfaces with a minimum roughness of 0.2 μm, and measurement results have a margin of 10%.
Investigation of the Influence of Cutting Parameters on Conical Pick Cutting Performance and Rock Damage
Authors: Wang Zhiwen , Zeng Qingliang , Wan Lirong , Lu Zhenguo , Wang Hongbin
Published: November 2022

Conical picks are applied to rock breaking, and the cutting parameters greatly influence cutting performance and rock damage. A conical pick rock-cutting numerical simulation model and software to provide a quantitative analysis of rock damage are established to research the influence of cutting parameters on cutting force and rock damage. The research results indicated that the average peak cutting force decreases with an increased cutting angle, and the average peak cutting force increases with a decreased cutting speed. The average peak cutting force of the second conical pick increases as the distance between double conical picks increases in the process of rock-cutting with double conical picks. There is a positive correlation between the volume of rock damage, the volume of rock breaking, and the cutting force of the conical pick. The research results provide a reference for optimizing the cutting parameters of conical picks.
Design and Analysis of 6-DoFs Upper Limb Assistant Rehabilitation Robot
Authors: Li Shuang , Wang Zhanli , Pang Zaixiang , Gao Moyao , Duan Zhifeng
Published: November 2022

This paper presents an assisted upper limb rehabilitation robot (ULRR) for patients who have experienced stroke who are in the middle and late stages of rehabilitation and have certain muscle strength. The ULRR can complete adduction and abduction motion of the shoulder joint (SJ) in the frontal plane in one step, which can save time and improve the efficiency of rehabilitation training. Based on the principles of ergonomics and rehabilitation medicine, the freedom degree of the upper limb and the motion range of each joint are determined, and the structure of the shoulder, the elbow, and the wrist joint of ULRR are designed. The kinematics model of the robot is established, and the kinematics equations are derived. Meanwhile, the simulation analysis and the workspace analysis of the robot are carried out, and the different movement forms of SJ adduction and abduction are compared and analyzed. Then, the trajectory of the robot is planned to complete the act of drinking water. Finally, an experimental platform is built to complete the ULRR to help participants complete the experiments of drinking water and active training. The experiments verify that the robot is suitable for rehabilitation tasks.
Fuzzy Differential Subordination and Superordination Results Involving the q-Hypergeometric Function and Fractional Calculus Aspects
Authors: Alb Lupaş Alina , Oros Georgia Irina
Published: November 2022

The concepts of fuzzy differential subordination and superordination were introduced in the geometric function theory as generalizations of the classical notions of differential subordination and superordination. Fractional calculus is combined in the present paper with quantum calculus aspects for obtaining new fuzzy differential subordinations and superordinations. For the investigated fuzzy differential subordinations and superordinations, fuzzy best subordinates and fuzzy best dominants were obtained, respectively. Furthermore, interesting corollaries emerge when using particular functions, frequently involved in research studies due to their geometric properties, as fuzzy best subordinates and fuzzy best dominants. The study is finalized by stating the sandwich-type results connecting the previously proven results.
A Novel Formulation of the Fractional Derivative with the Order α≥0 and without the Singular Kernel
Authors: Jassim Hassan Kamil , Hussein Mohammed A.
Published: November 2022

A new definition of fractional derivative (NFD) with order α≥0, is developed in this paper. The new derivative has a smooth kernel that takes on two different representations for the temporal and spatial variables. The advantage of the proposed approach over traditional local theories and fractional models with a singular kernel lies in the possibility that there is a class of problems capable of describing scale-dependent fluctuations and material heterogeneities. Moreover, it has been shown that the NFD converges to the classical derivative faster than some other fractional derivatives.
Machine Learning Based Approach for Automated Cervical Dysplasia Detection Using Multi-Resolution Transform Domain Features
Authors: Bora Kangkana , Mahanta Lipi B. , Borah Kasmika , Chyrmang Genevieve , Barua Barun , Mallik Saurav , Das Himanish Shekhar , Zhao Zhongming
Published: November 2022

Pattern detection and classification of cervical cell dysplasia can assist with diagnosis and treatment. This study aims to develop a computational model for real-world applications for cervical dysplasia that has the highest degree of accuracy and the lowest computation time. Initially, an ML framework is created, which has been trained and evaluated to classify dysplasia. Three different color models, three multi-resolution transform-based techniques for feature extraction (each with different filters), two feature representation schemes, and two well-known classification approaches are developed in conjunction to determine the optimal combination of “transform (filter) ⇒ color model ⇒ feature representation ⇒ classifier”. Extensive evaluations of two datasets, one is indigenous (own generated database) and the other is publicly available, demonstrated that the Non-subsampled Contourlet Transform (NSCT) feature-based classification performs well, it reveals that the combination “NSCT (pyrexc,pkva), YCbCr, MLP” gives most satisfactory framework with a classification accuracy of 98.02% (average) using the F1 feature set. Compared to two other approaches, our proposed model yields the most satisfying results, with an accuracy in the range of 98.00–99.50%.
Exploration of Multiple Transfer Phenomena within Viscous Fluid Flows over a Curved Stretching Sheet in the Co-Existence of Gyrotactic Micro-Organisms and Tiny Particles
Authors: Ragupathi Pachiyappan , Ahammad N. Ameer , Wakif Abderrahim , Shah Nehad Ali , Jeon Yongseok
Published: November 2022

In the present study, the magnetohydrodynamics (MHD) bio-convective flow and heat transfer of nanofluid, due to the swimming of the gyrotactic micro-organisms over a curved stretched sheet, is examined. In addition, thermophoresis and Brownian motion behaviors are also investigated by assuming slip conditions at the boundary. A non-linear system of partial differential equations (PDEs) is reduced to a system of ordinary differential equations (ODEs). For convergent solutions, the obtained ODE system is solved by the use of the BVP4C routine integrated MATLAB package. In addition, the impacts of different influential parameters on motile micro-organisms, temperature, velocity, and concentration profiles are deliberated. The velocity field is observed to be reduced when the slip parameter increases. As the main results, it is demonstrated that the distribution of motile microorganisms against the curvature parameter decreases significantly. Similarly, it is found that the nanofluid parameters (i.e., Brownian motion and thermophoresis parameters) and the Peclet number reduce the motile micro-organisms’ number. On the other hand, it is evidenced that the motile micro-organisms’ distribution can be improved with an increase in bio-convective Schmidt number.
HSICCR: A Lightweight Scoring Criterion Based on Measuring the Degree of Causality for the Detection of SNP Interactions
Authors: Zheng Junxi , Zeng Juan , Wang Xinyang , Li Gang , Zhu Jiaxian , Wang Fanghong , Tang Deyu
Published: November 2022

Recently, research on detecting SNP interactions has attracted considerable attention, which is of great significance for exploring complex diseases. The formulation of effective swarm intelligence optimization algorithms is a primary resolution to this issue. To achieve this goal, an important problem needs to be solved in advance; that is, designing and selecting lightweight scoring criteria that can be calculated in O(m) time and can accurately estimate the degree of association between SNP combinations and disease status. In this study, we propose a high-accuracy scoring criterion (HSICCR) by measuring the degree of causality dedicated to assessing the degree. First, we approximate two kinds of dependencies according to the structural equation of the causal relationship between epistasis SNP combination and disease status. Then, inspired by these dependencies, we put forward this scoring criterion that integrates a widely used method of measuring statistical dependencies based on kernel functions (HSIC). However, the computing time complexity of HSIC is O(m2), which is too costly to be an integral part of the scoring criterion. Since the sizes of the sample space of the disease status, SNP loci and SNP combination are small enough, we propose an efficient method of computing HSIC for variables with a small sample in O(m) time. Eventually, HSICCR can be computed in O(m) time in practice. Finally, we compared HSICCR with five representative high-accuracy scoring criteria that detect SNP interactions for 49 simulation disease models. The experimental results show that the accuracy of our proposed scoring criterion is, overall, state-of-the-art.
An Adapted Discrete Lindley Model Emanating from Negative Binomial Mixtures for Autoregressive Counts
Authors: van der Merwe Ané , Ferreira Johannes T.
Published: November 2022

Analysing autoregressive counts over time remains a relevant and evolving matter of interest, where oftentimes the assumption of normality is made for the error terms. In the case when data are discrete, the Poisson model may be assumed for the structure of the error terms. In order to address the equidispersion restriction of the Poisson distribution, various alternative considerations have been investigated in such an integer environment. This paper, inspired by the integer autoregressive process of order 1, incorporates negative binomial shape mixtures via a compound Poisson Lindley model for the error terms. The systematic construction of this model is offered and motivated, and is analysed comparatively against common alternate candidates with a number of simulation and data analyses. This work provides insight into noncentral-type behaviour in both the continuous Lindley model and in the discrete case for meaningful application and consideration in integer autoregressive environments.
Employing Quantum Fruit Fly Optimization Algorithm for Solving Three-Dimensional Chaotic Equations
Authors: Zainel Qasim M. , Darwish Saad M. , Khorsheed Murad B.
Published: November 2022

In a chaotic system, deterministic, nonlinear, irregular, and initial-condition-sensitive features are desired. Due to its chaotic nature, it is difficult to quantify a chaotic system’s parameters. Parameter estimation is a major issue because it depends on the stability analysis of a chaotic system, and communication systems that are based on chaos make it difficult to give accurate estimates or a fast rate of convergence. Several nature-inspired metaheuristic algorithms have been used to estimate chaotic system parameters; however, many are unable to balance exploration and exploitation. The fruit fly optimization algorithm (FOA) is not only efficient in solving difficult optimization problems, but also simpler and easier to construct than other currently available population-based algorithms. In this study, the quantum fruit fly optimization algorithm (QFOA) was suggested to find the optimum values for chaotic parameters that would help algorithms converge faster and avoid the local optimum. The recommended technique used quantum theory probability and uncertainty to overcome the classic FA’s premature convergence and local optimum trapping. QFOA modifies the basic Newtonian-based search technique of FA by including a quantum behavior-based searching mechanism used to pinpoint the position of the fruit fly swarm. The suggested model has been assessed using a well-known Lorenz system with a specified set of parameter values and benchmarked signals. The results showed a considerable improvement in the accuracy of parameter estimates and better estimation power than state-of-the art parameter estimation approaches.
The Inhibitory Effect of Phycocyanin Peptide on Pulmonary Fibrosis In Vitro
Authors: Liu Run-Ze , Li Wen-Jun , Zhang Juan-Juan , Liu Zheng-Yi , Li Ya , Liu Chao , Qin Song
Published: November 2022

Phycocyanin is an excellent antioxidant with anti-inflammatory effects on which recent studies are growing; however, its specific target remains unclear. Linear tetrapyrrole compounds such as bilirubin have been shown to lead to the induction of heme oxygenase 1 expression in vivo, thus achieving antioxidant and anti-inflammatory effects. Phycocyanin is bound internally with linear tetrapyrrole phycocyanobilin in a similar structure to bilirubin. We speculate that there is probably a way of inducing the expression of heme oxygenase 1, with which tissue oxidative stress and inflammation can be inhibited, thus inhibiting pulmonary fibrosis caused by oxidative damage and inflammation of lung. By optimizing the enzymatic hydrolysis process, phycocyanobilin-bound phycocyanin peptide were obtained, and its in vitro antioxidant, anti-inflammatory, and anti-pulmonary fibrosis activities were investigated. The results show that the phycocyanobilin peptide was able to alleviate oxidative and inflammatory damage in cells through the Keap1-Nrf2-HO-1 pathway, which in turn relieved pulmonary fibrosis symptoms.
Comparison of the Ammonia Trapping Performance of Different Gas-Permeable Tubular Membrane System Configurations
Authors: Soto-Herranz María , Sánchez-Báscones Mercedes , García-González María Cruz , Martín-Ramos Pablo
Published: November 2022

The technology of gas-permeable tubular membranes (GPMs) is promising in reducing ammonia emissions from livestock manure, capturing NH3 in an acidic solution, and obtaining final products suitable for valorization as fertilizers, in line with the principles of the circular economy. This study aimed to evaluate the performance of several e-PTFE membrane systems with different configurations for the recovery of NH3 released from pig slurry. Ten different configurations were tested: only a submerged membrane, only a suspended membrane in the same chamber, only a suspended membrane in an annex chamber, a submerged membrane + a suspended membrane in the same chamber, and a submerged membrane + a suspended membrane in an annex chamber, considering in each case the scenarios without and with agitation and aeration of the slurry. In all tests, sulfuric acid (1N H2SO4) was used as the NH3 capture solution, which circulated at a flow rate of 2.1 L·h−1. The results showed that NH3-N removal rates ranged from 36–39% (for systems with a single submerged or suspended membrane without agitation or aeration of the slurry) to 70–72% for submerged + suspended GPM systems with agitation and aeration. In turn, NH3-N recovery rates were found to be between 44–54% (for systems with a single membrane suspended in an annex compartment) and 88–91% (for systems based on a single submerged membrane). However, when choosing a system for farm deployment, it is essential to consider not only the capture and recovery performance of the system, but also the investment and operating costs (ranging from 9.8 to 21.2 €/kg N recovered depending on the selected configuration). The overall assessment suggests that the simplest systems, based on a single membrane, may be the most recommendable.
Effect of Cobalt Ferrite Nanoparticles in a Hydrophilic Shell on the Conductance of Bilayer Lipid Membrane
Authors: Anosov Andrey , Koplak Oksana , Smirnova Elena , Borisova Elizaveta , Korepanova Eugenia , Derunets Alice
Published: November 2022

We measured the conductance of bilayer lipid membranes of diphytanoylphosphatidylcholine induced by interaction with cubic magnetic nanoparticles (MNPs) of cobalt ferrite 12 and 27 nm in size and coated with a hydrophilic shell. The MNP coating is human serum albumin (HSA) or polyethylene glycol (PEG). The interaction of nanoparticles added to the bulk solution with the lipid bilayer causes the formation of metastable conductive pores, which, in turn, increases the integral conductance of the membranes. The increase in conductance with increasing MNP concentration was practically independent of the particle size. The dependence of the bilayer conductance on the concentration of PEG-coated MNPs was much weaker than that on the concentration with a shell of HSA. Analyzing the current traces, we believe that the conductive pores formed as a result of the interaction of nanoparticles with the membrane can change their size, remaining metastable. The form of multilevel current traces allows us to assume that there are several metastable pore states close in energy. The average radius of the putative cylindrical pores is in the range of 0.4–1.3 nm.
Development of Pomegranate Peel Extract and Nano ZnO Co-Reinforced Polylactic Acid Film for Active Food Packaging
Authors: Dai Lu , Li Runli , Liang Yanmin , Liu Yingsha , Zhang Wentao , Shi Shuo
Published: November 2022

The multifunctional packaging used for fresh food, such as antioxidant and antimicrobial packaging, can reduce food waste. In this work, a polylactic acid (PLA)-based composite film with antioxidant and antibacterial properties was prepared by using nano-zinc oxide (ZnONPs) and pomegranate peel extract (PEE) via the solvent-casting method. Different amounts of PEE (0.5, 1, 1.5 and 2 wt%) and 3 wt% ZnONPs were added to PLA to produce the active films. The results of various characterizations (SEM, XRD, etc.) showed that ZnONPs and PEE were uniformly dispersed in PLA film. Compared to PLA films, the PLA/ZnONPs/PEE films showed an increased UV barrier, water vapor permeability and elongation at break, and decreased transparency and tensile strength. In addition, the antioxidant activity of the composite film was evaluated based on DPPH and ABTS. The maximum DPPH and ABTS scavenging activities of PLA/ZnONPs/PEE were 96.2 ± 0.8% and 93.1 ± 0.5%. After 24 h, PLA/ZnONPs/PEE composite film inhibited 1.4 ± 0.05 Log CFU/mL of S. aureus and 8.2 ± 0.35 Log CFU/mL of E. coli, compared with the blank group. The results showed that PLA/ZnONPs/PEE composite film had good antibacterial and antioxidant activities. Therefore, the composite film showed great potential for food packaging.
On the Choice of Different Water Model in Molecular Dynamics Simulations of Nanopore Transport Phenomena
Authors: Park Chulwoo , Robinson Ferlin , Kim Daejoong
Published: November 2022

The water transport through nanoporous multilayered graphene at 300k is investigated using molecular dynamics (MD) simulation with different water models in this study. We used functionalized and non-functionalized membranes along with five different 3-point rigid water models: SPC (simple point charge), SPC/E (extended simple point charge), TIP3P-FB (transferable intermolecular potential with 3 points—Force Balance), TIP3P-EW (transferable intermolecular potential with 3 points with Ewald summation) and OPC3 (3-point optimal point charge) water models. Based on our simulations with two water reservoirs and a porous multilayered graphene membrane in-between them, it is evident that the water transport varies significantly depending on the water model used, which is in good agreement with previous works. This study contributes to the selection of a water model for molecular dynamics simulations of water transport through multilayered porous graphene.
Development of a Moving-Bed Ironmaking Process for Direct Gaseous Reduction of Iron Ore Concentrate
Authors: Sohn Hong Yong , Roy Syamantak
Published: November 2022

A novel horizontal moving-bed ironmaking process has been developed at the University of Utah. This process uses iron concentrate directly without sintering or pelletization and reduces it with hydrogen in the temperature range of 500–1000 °C. The work started with the determination of the particle kinetics, which was then combined with diffusional effects to analyze the reduction rate of a particle bed. Based on the kinetics formulation, a mathematical model of the furnace for the proposed technology was developed for a modest industrial ironmaking operation designed to produce iron at a rate of 0.1 Mtpy.
Deformation Behavior and Connection Mechanism of EMP Connections in Aluminum Pipe Joints
Authors: Yu Haiping , Ma Boyang , He Yihan , Qi Yang
Published: November 2022

The joint is a key component of the aviation piping system, with severe performance requirements and better requirements for connection technology. With a focus on the manufacturing demand of AA6061 aerospace pipe joints, as well as the characteristics of EMP forming technology, this paper investigates the deformation behavior of the EMP forming on AA6061 aerospace pipe joints, the influence of process parameters on the deformation behavior, and the deformation mechanism of the tube wall. The results show that under the conditions of this paper, with an increase in the initial tube-sleeve gap and discharge voltage, the degree of local deformation of the AA6061 tube wall and the trench embedding rate increase. Keeping the width and depth of the grooves as 1.14 mm and 0.23 mm, the embedding rate of the grooves is less than 85% under the clearance conditions of 0.11 mm and 0.5 mm, while the lowest voltage for the embedding rate of the grooves to reach more than 85% under the clearance conditions of 1 mm, 1.5 mm and 2 mm is 7 kV, 6 kV, and 5 kV, respectively. The metallographic organization of the deformation area shows that the tube is deformed by the intense shear at the edge of the groove of the tube sleeve, thereby showing streamlined organization characteristics and deformation characteristics. The electromagnetic pulse forming process of the AA6061 tube is mainly divided into two stages: free bulging and local deformation; the inertia of high-rate deformation causes the groove filling to exhibit volume deformation characteristics in the local deformation stage.
The Effect of Thermomechanical Processing Sequence on the Dispersoid Distribution and Final Mechanical Properties of Spray-Formed Al-Cu-Li Alloy
Authors: Ning Yaru , Zhang Xingchen , Huang Yunjia , Ding Lipeng , Lei Xiuchuan , Weng Yaoyao , Cao Lingfei , Zhang Ke , Jia Zhihong
Published: November 2022

Controlling the formation of the β′ (Al3Zr) phase is pivotal for regulating the recrystallization and thus the mechanical properties of the spray formed 2195 (Al-Cu-Li) alloy. In a conventional “homogenization-extrusion” process, the precipitation of β′ is severely affected by the presence of the T1(Al2CuLi) phase in the as-deposited alloy, leading to an inhomogeneous distribution of the β′ phase. In the present work, we propose a new thermomechanical processing (TMP)—swapping the order of the homogenization and extrusion processes. The microstructures and properties of the new proposed TMP were systematically studied at various stages of the alloy treatment and compared with the out of the conventional TMP. It was revealed that the introduction of the extrusion process on the as-deposited alloy can break the continuous network of primary phases and dissolve the T1 phase, promoting a uniform distribution of the β′ phase during subsequent two-step homogenization. During solution treatment, the new TMP is more effectively in suppressing the formation of a coarse grain layer at sheet surface, while after final peak aging, the new TMP produces a lower alloy strength but a higher elongation, due mainly to the smaller thickness reduction during deformation. The new proposed TMP technique provides a new insight into regulating the mechanical properties of Al-Cu-Li alloys.
CFD–DPM Simulation Study of the Effect of Powder Layer Thickness on the SLM Spatter Behavior
Authors: Cao Liu , Zhang Qindan , Meng Ruifan
Published: November 2022

Selective Laser Melting (SLM) has significant advantages in manufacturing complex structural components and refining the alloy microstructure; however, spatter, as a phenomenon that accompanies the entire SLM forming process, is prone to problems such as inclusions, porosity, and low powder recovery quality. In this paper, a Computational Fluid Dynamics–Discrete Particle Method (CFD–DPM) simulation flow for predicting the SLM spatter behavior is established based on the open-source code OpenFOAM. Among them, the single-phase flow Navier–Stokes equation is used in the Eulerian framework to equivalently describe the effect of metal vapor and protective gas on the flow field of the forming cavity, and the DPM method is used in the Lagrangian framework to describe the metal particle motion, and the factors affecting the particle motion include particle–particle collision, particle–wall collision, fluid drag force, gravity, buoyancy force, and additional mass force. In addition, the equivalent volume force and fluid drag force are used to characterize the fluid–particle coupling interaction. For the spatter behavior and powder bed denudation phenomenon, the calculation results show that the spatter height and the drop location show a clear correlation, and the powder bed denudation phenomenon is caused by the high-speed gas flow, causing the surrounding gas to gather in the forming area, which in turn drives the motion of the powder bed particles. For the effect of powder layer thickness on spatter and powder bed denudation, the calculation results show that the effect of powder layer thickness on the number of spatters is large (when the thickness was increased from 50 μm to 100 μm, the number of spatters increased by 157%), but the effect on spatter height and drop location distribution is small. When the powder layer thickness is small, the width of the denudation zone is significantly larger, but when the powder layer reaches a certain thickness, the width of the denudation zone does not show significant changes. It should be noted that the presented model has not been directly validated by experiments so far due to the difficulty of tracking the large-scale motion of SLM spatter in real time by current experimental means.
Effect of Myricetin on Lipid Metabolism in Primary Calf Hepatocytes Challenged with Long-Chain Fatty Acids
Authors: Yang Wei , Yang Mingmao , Tian Yan , Jiang Qianming , Loor Juan , Cao Jie , Wang Shuang , Gao Changhong , Fan Wenwen , Zhang Bingbing , Xu Chuang
Published: November 2022

Triacylglycerol (TAG) accumulation and oxidative damage in hepatocytes induced by high circulating concentrations of fatty acids (FA) are common after calving. In order to clarify the role of myricetin on lipid metabolism in hepatocytes when FA metabolism increases markedly, we performed in vitro analyses using isolated primary calf hepatocytes from three healthy female calves (1 d old, 42 to 48 kg). Two hours prior to an FA challenge (1.2 mM mix), the hepatocytes were treated with 100 μM (M1), 50 μM (M2), or 25 μM (M3) of myricetin. Subsequently, hepatocytes from each donor were challenged with or without FA for 12 h in an attempt to induce metabolic stress. Data from calf hepatocyte treatment comparisons were assessed using two-way repeated-measures (RM) ANOVA with subsequent Bonferroni correction. The data revealed that hepatocytes challenged with FA had greater concentrations of TAG and nonesterified fatty acids (NEFA), oxidative stress-related MDA and H2O2, and mRNA and protein abundance of lipid synthesis-related SREBF1 and inflammatory-related NF-κB. In addition, the mRNA abundance of the lipid synthesis-related genes FASN, DGAT1, DGAT2, and ACC1; endoplasmic reticulum stress-related GRP79 and PERK; and inflammatory-related TNF-α also were upregulated. In contrast, the activity of antioxidant SOD (p < 0.01) and concentrations of GSH (p < 0.05), and the protein abundance of mitochondrial FA oxidation-related CPT1A, were markedly lower. Compared with FA challenge, 50 and 100 μM myricetin led to lower concentrations of TAG, NEFA, MDA, and H2O2, as well as mRNA and protein abundance of SREBF1, DGAT1, GRP78, and NF-κB. In contrast, the activity of SOD (p < 0.01) and mRNA and protein abundance of CPT1A were markedly greater. Overall, the results suggest that myricetin could enhance the antioxidant capacity and reduce lipotoxicity, endoplasmic reticulum stress, and inflammation. All of these effects can help reduce TAG accumulation in hepatocytes.