bluuebunny/crossref_metadata_2025 huggingface dataset:
Combined Jasmonic Acid and Ethylene Treatment Induces Resistance Effect in Faba Bean Plants Against Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae)
Authors: Jia Yu-Lian , Zhang Tao , Zhi Jun-Rui , Tuo Lu , Yue Wen-Bo , Li Ding-Yin , Liu Li
Published: November 2022

Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) is a serious invasive pest in China. In this study, we determined whether exogenous jasmonic acid (JA) and ethylene (ET) treatments could induce resistance against F. occidentalis in faba bean plants. First, we investigated the effects of different concentrations of JA or ET alone on F. occidentalis and then assessed the effects of optimal concentrations of JA and ET combined. Our results showed that the optimal concertation of JA was 2 mmol/L and ET was 0.5 mmol/L. JA + ET mixture showed the greatest inhibitory effect in terms of oviposition and feeding. JA with ET was found to induce changes in the activities of lipoxygenase (LOX), allene oxide synthase (AOS), polyphenol oxidase (PPO), 1-aminocyclopropane 1-carboxylic acid synthase (ACS), and trypsin inhibitor (TI). This treatment also activated or inhibited the relative expression levels of LOX1, ACO2, ACS2, and AP2/ERF. Treatment of faba bean plants with JA and ET significantly prolonged F. occidentalis development and adult preoviposition period, significantly reduced per-female oviposition, and altered male longevity and offspring demographic parameters. These results indicate that JA with ET can induce defenses against the growth and development of F. occidentalis in faba bean plants.
Crystallographic and Physicochemical Analysis of Bovine and Human Teeth Using X-ray Diffraction and Solid-State Nuclear Magnetic Resonance
Authors: Hiraishi Noriko , Gondo Tadamu , Shimada Yasushi , Hill Robert , Hayashi Fumiaki
Published: November 2022

Dental research often uses bovine teeth as a substitute for human teeth. The aim of this study was to evaluate differences in the crystalline nanostructures of enamel and dentin between bovine and human teeth, using X-ray diffraction (XRD) and solid-state nuclear magnetic resonance (NMR). The crystallite size (crystallinity) and microstrains were analyzed using XRD with the Rietveld refinement technique and the Halder–Wagner method. The 31P and 1H NMR chemical environments were analyzed by two-dimensional (2D) 1H-31P heteronuclear-correlation (HETCOR) magic-angle spinning (MAS) NMR spectroscopy. Enamel had a greater crystallite size and fewer microstrains than dentin for both bovine and human teeth. When compared between the species, the bovine apatite had a smaller crystallite size with more microstrains than the human apatite for both dentin and enamel. The 2D HETCOR spectra demonstrated that a water-rich layer and inorganic HPO42− ions were abundant in dentin; meanwhile, the hydroxyl group in the lattice site was more dominant in enamel. A greater intensity of the hydroxyl group was detected in human than in bovine for both dentin and enamel. For 31P projections, bovine dentin and bovine enamel have wider linewidths than human dentin and human enamel, respectively. There are differences in the crystallite profile between human and bovine. The results of dental research should be interpreted with caution when bovine teeth are substituted for human teeth.
Sinus Mucosal Damage Triggered by Synthetic or Xenogeneic Bone Substitutes: A Histological Analysis in Rabbits
Authors: Omori Yuki , Botticelli Daniele , Migani Stefano , Ferreira Balan Vitor , Pires Godoy Eduardo , Xavier Samuel
Published: November 2022

Background: It has been shown in rabbit models that the sinus mucosa in contact with graft particles might experience a progressive thinning and perforations. The phenomenon depends on the graft used. Hence, the aim of the present study was to compare the damaging effects of a synthetic of a xenogeneic graft. Methods: Forty New Zealand rabbits received a bilateral sinus elevation. Both sinuses of twenty rabbits were grafted with a biphasic 60% hydroxyapatite and 40% β-tricalcium phosphate while the other twenty received a deproteinized bovine bone mineral graft. Thinned sites (<40 µm) and perforations on the mucosa in contact with graft particles were evaluated after 2 and 10 weeks (ten animals each period). The width of the pseudostratified epithelium was also measured as control. Results: After 2 weeks of healing, 61 thinned sites were detected in the Synthetic group and 49 in the Xenogeneic group. After 10 weeks, the number of thinned mucosae increased to 79 sites in the Synthetic group (p = 0.222 between periods), and to 114 sites in the Xenogeneic group (p = 0.030 between groups; p = 0.001 between periods). Perforations were few in the 2-week period, two in two sinuses out of 20 in the Synthetic group, and four in two sinuses out of 20 in the Xenogeneic group (p = 0.721). In the 10-week period, the perforations increased to eight in the Synthetic group, distributed in six sinuses out of 20, and to sixteen in the Xenogeneic group, distributed in 11 sinuses out of 20 (p = 0.082). The pseudostratified epithelium presented a reduced width at the thinned sites. Conclusions: The contact with synthetic or xenogeneic grafts will induce thinning and possible perforations of the sinus mucosa. This effect will increase over time, and it is stronger at the xenogeneic than the synthetic graft.
Al-Cu-Mg Alloy Powder Reinforced with Graphene Nanoplatelets: Morphology, Flowability and Discrete Element Simulation
Authors: Pekok Mulla Ahmet , Setchi Rossitza , Ryan Michael , Gu Heng , Han Quanquan , Gu Dongdong
Published: November 2022

Research in metal matrix composites (MMCs) indicates that superior mechanical properties may be achieved by embedding reinforcement materials. However, the development of new composite powder for additive manufacturing requires an in-depth understanding of its key characteristics prior to its use in the fabrication process. This paper focuses on the low-energy ball milling (LEBM) of aluminium 2024 alloy (AA2024) reinforced with graphene nanoplatelets (GNPs). The main aim is to investigate the effect of the milling time (from 0.5 to 16 h) on the morphology and flowability of the powder. The study shows that, while short milling times (under 2 h) could not break the Van der WaRals forces between nanoparticles, GNPs were well separated and sufficiently covered the powder surface after 4 h of milling, thanks to the continuously applied impact energy. Longer milling time provides increasingly similar flowability results, confirmed by both the experimental work and discrete element model (DEM) simulations. Moreover, the ball milling process decreases the crystallite size of the milled powder by 24%, leading to a 3% higher microhardness. Lastly, the surface energy of the powder was determined as 1.4 mJ/m2 by DEM, using the angle of repose of the as-received powder from experimental work.
A Study on the Vortex Induced Vibration of a Cylindrical Structure with Surface Bulges
Authors: Xu Haoyuan , Wang Jie , Li Zhiqing , Liu Kaihua , Yu Jiawei , Zhou Bo
Published: November 2022

Inspired by the cactus in nature, a cactus-like cross-sectional structure was proposed to achieve the VIV suppression. The VIV of the elastically mounted cylinder was realized based on the ANSYS Fluent and User Defined Function (UDF). The dynamic motion of the cylinder was solved by the single-step time integration algorithms Newmark-β method. The in-house code was first validated by studying the 2DOF VIV of a circular cylinder with small mass ratio over the range U*=2~13, and the results agree well with the published literature. Then, the performance of surface bulge on VIV suppression was studied and four different coverage ratios (CR) were considered, i.e., 0%, 20%, 33%, and 40%. The VIV of a bulged cylinder can be effectively suppressed. CR20 performs the best in VIV suppression and the suppression efficiency in streamwise and transverse direction are 44.6% and 63.1%, respectively. The mechanism of surface bulge on the VIV suppression is the shift of separation point of the shear layer and vortices form between the surface bulges.
Water Circulation, Temperature, Salinity, and pCO2 Distribution in the Surface Layer of the East Kamchatka Current
Authors: Andreev Andrey , Pipko Irina
Published: November 2022

The ship-borne observations of the temperature, salinity, pCO2 (1995–2020) and satellite geostrophic velocity fields, SST, and chlorophyll concentration are used to identify the factors that determine the spatio-temporal variability of seawater parameters on the western boundary of the subarctic North Pacific. In winter, the surface layer of the East Kamchatka Current (EKC) was characterized by two types of water: the waters with a negative temperature (−1.0–−0.5 °C) and salinity of 32.4–32.9 and waters with a positive temperature (0.4–1.7 °C) and salinity of 33.0–33.1. The source of water with negative (positive) temperature and decreased (increased) salinity for the EKC zone is the Bering Sea shelf (Aleutian Basin). The surface waters in the eastern Kamchatka area in winter were close to gas equilibrium with the atmosphere or supersaturated with carbon dioxide (pCO2 = 380–460 µatm). In summer, extremely low pCO2 values (140–220 µatm) in the surface layer of the eastern Kamchatka and the northern Kuril Islands regions have been associated with the decreased salinity (32.1–32.6) of the waters. The distributions of the temperature, salinity, and pCO2 in the surface layer of the central Kuril Islands are determined by the location and intensity of the Kuril eddies and the EKC stream jets. The water mixing in the central Kuril Straits and the Kruzenshterna Bank area leads to increased salinity (33.2–33.4) and high values of pCO2 (480–670 µatm) in the surface layer of the EKC. The comparison of the pCO2 data collected in winter demonstrates an increase in pCO2 between 1998/2001 and 2018/2020 at about 50 µatm in the surface waters with a salinity of 33.0–33.1, which is in agreement with an increase in pCO2 in the atmosphere at 46 µatm (from 368 to 414 µatm) during this period.
First Record of Aspergillus fijiensis as an Entomopathogenic Fungus against Asian Citrus Psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae)
Authors: Yan Jianquan , Liu Hao , Idrees Atif , Chen Fenghao , Lu Huilin , Ouyang Gecheng , Meng Xiang
Published: November 2022

The Asian citrus psyllid Diaphorina citri Kuwayama (Hemiptera: Liviidae) is the most widespread and devastating pest species in citrus orchards and is the natural vector of the phloem-limited bacterium that causes Huanglongbing (HLB) disease. Thus, reducing the population of D. citri is an important means to prevent the spread of HLB disease. Due to the long-term use of chemical control, biological control has become the most promising strategy. In this study, a novel highly pathogenic fungal strain was isolated from naturally infected cadavers of adult D. citri. The species was identified as Aspergillus fijiensis using morphological identification and phylogenetic analysis and assigned the strain name GDIZM-1. Tests to detect aflatoxin B1 demonstrated that A. fijiensis GDIZM-1 is a non-aflatoxin B1 producer. The pathogenicity of the strain against D. citri was determined under laboratory and greenhouse conditions. The results of the laboratory study indicated that nymphs from the 1st to 5th instar and adults of D. citri were infected by A. fijiensis GDIZM-1. The mortality of nymphs and adults of D. citri caused by infection with A. fijiensis increased with the concentration of the conidial suspension and exposure time, and the median lethal concentration (LC50) and median lethal time (LT50) values gradually decreased. The mortality of D. citri for all instars was higher than 70%, with high pathogenicity at the 7th day post treatment with 1 × 108 conidia/mL. The results of the greenhouse pathogenicity tests showed that the survival of D. citri adults was 3.33% on the 14th day post-treatment with 1 × 108 conidia/mL, which was significantly lower than that after treatment with the Metarhizium anisopliae GDIZMMa-3 strain and sterile water. The results of the present study revealed that the isolate of A. fijiensis GDIZM-1 was effective against D. citri and it provides a basis for the development of a new microbial pesticide against D. citri after validation of these results in the field.
Screening, and Optimization of Fermentation Medium to Produce Secondary Metabolites from Bacillus amyloliquefaciens, for the Biocontrol of Early Leaf Spot Disease, and Growth Promoting Effects on Peanut (Arachis hypogaea L.)
Authors: Ahsan Taswar , Zang Chaoqun , Yu Shuyi , Pei Xue , Xie Jinhui , Lin Ying , Liu Xiaozhou , Liang Chunhao
Published: November 2022

A novel Bacillus amyloliquefaciens BAM strain, with novel fermentation nutrient mediums and compositions, could produce potent antifungal secondary metabolites, as the existing strains face resistance from fungus pathogens. In the current study, we introduced two novel nutrient mediums for the fermentation process, semolina and peanut root extract, as carbon and nitrogen sources in order to maximize the antifungal effects of B. amyloliquefaciens against Cercaspora arachidichola to control early leaf spot disease in peanuts. Based on a single-factor test and the central composite design of response surface methodology, the optimum fermentation medium for Bacillus amyloliquefaciens antagonistic substance was determined, containing 15 gm/L of semolina flour, 12.5 gm/L of beef extract, and 0.5 gm/L of magnesium sulfate, which inhibited the fungal growth by 91%. In vitro, antagonistic activity showed that the fermentation broth of B. amyloliquefaciens BAM with the optimized medium formulation had an inhibition rate of (92.62 ± 2.07)% on the growth of C. arachidichola. Disease control effects in pot experiments show that the pre-infection spray of B. amyloliquefaciens BAM broth had significant efficiency of (92.00 ± 3.79)% in comparison to post-infection spray. B. amyloliquefaciens BAM broth significantly promoted peanut plant growth and physiological parameters and reduced the biotic stress of C. archidechola. Studies revealed that B. amyloliquefaciens BAM with a novel fermentation formulation could be an ideal biocontrol and biofertilizer agent and help in early disease management of early leaf spots in peanuts.
The Role of Phialocephala fortinii in Improving Plants’ Phosphorus Nutrition: New Puzzle Pieces
Authors: Mikheev Vyacheslav S. , Struchkova Irina V. , Ageyeva Maria N. , Brilkina Anna A. , Berezina Ekaterina V.
Published: November 2022

Plants’ mineral nutrition in acidic soils can be facilitated by phosphate solubilizing fungi inhabiting the root systems of these plants. We attempt to find dark septate endophyte (DSE) isolates in the roots of wild-heather plants, which are capable of improving plants’ phosphorus nutrition levels. Bright-field and confocal laser scanning microscopy were used for the visualization of endophytes. A model system of co-cultivation with Vaccinium macrocarpon Ait. was used to study a fungal isolate’s ability to supply plants with phosphorus. Fungal phytase activity and phosphorus content in plants were estimated spectrophotometrically. In V. vitis-idaea L. roots, we obtained a Phialocephala fortinii Wang, Wilcox DSE2 isolate with acid phytase activity (maximum 6.91 ± 0.17 U on 21st day of cultivation on potato-dextrose broth medium) and the ability to accumulate polyphosphates in hyphae cells. The ability of the isolate to increase both phosphorus accumulation and biomass in V. macrocarpon is also shown. The data obtained for the same isolate, as puzzle pieces put together, indicate the possible mediation of P. fortinii DSE2 isolate in the process of phosphorus intake from inorganic soil reserves to plants.
Ecological Evaluation of Sponge City Landscape Design Based on Aquatic Plants Application
Authors: Jiang Dan , Hua Rui , Shao Jian
Published: November 2022

Urbanization increases the impervious surface of land and disrupts the hydrological cycle of urban water resources. Optimum landscape design based on climatic and geographical factors can reduce the destructive effects of urban development on surface and subsurface flows. The construction of a sponge city is an essential step towards achieving this structure. Aquatic plants are the most important component of the ecological regeneration of urban landscapes. The land cover changes caused by aquatic plants reduce the speed of water and increase the penetration of runoff into the porous environment. In addition, not only can the use of aquatic plants as the main component of water saving for ecological restoration control water erosion, but it can also have a positive effect on landscape architecture. Therefore, the aim of this study was to develop a multi-objective urban landscape design model based on the use of aquatic plants. Moreover, the limitations of improving the urban ecosystem with aquatic plants were analyzed based on the theory of ecological restoration in a sponge city. The required area for the cultivation of these plants was calculated according to the flood return periods and the two objective functions of land slope and runoff rate. The results show that surface runoff decreased by 15% and that rainfall and flood decreased by 21% for a 50-year return period.
19β,28-Epoxy-18α-olean-3β-ol-2-furoate from Allobetulin (19β,28-Epoxy-18α-olean-3β-ol)
Authors: Lugemwa Fulgentius Nelson
Published: November 2022

The E ring of betulin rearranges and forms a cyclic ether when treated with an acid. Treatment of betulin with iodine generated hydrogen iodide in situ, which went on to promote the rearrangement at C-19 and C-20, followed by cyclization to form allobetulin. A reaction of allobetulin with 2-furoyl chloride yielded 19β,28-Epoxy-18α-olean-3β-ol-2-furoate.
N2,N6-Bis(6-iodo-2-methyl-4-oxoquinazolin-3(4H)-yl)pyridine-2,6-dicarboxamide
Authors: Molnar Maja , Komar Mario , Jerković Igor
Published: November 2022

A green chemistry method was applied in the synthesis of N2,N6-bis(6-iodo-2-methyl-4-oxoquinazolin-3(4H)-yl)pyridine-2,6-dicarboxamide. The desired compound was synthesized mechanochemically, using a choline chloride-based deep eutectic solvent as a catalyst. The synthesis took 20 min and the new compound was characterized using different spectral methods.
Behavior of Silica Nanoparticles Synthesized from Rice Husk Ash by the Sol–Gel Method as a Photocatalytic and Antibacterial Agent
Authors: Alhadhrami A. , Mohamed Gehad G. , Sadek Ahmed H. , Ismail Sameh H. , Ebnalwaled A. A. , Almalki Abdulraheem S. A.
Published: November 2022

Silica nanoparticles (SiO2 NPs) are one of the most well-studied inorganic nanoparticles for many applications. They offer the advantages of tunable size, biocompatibility, porous structure, and larger surface area. Thus, in this study, a high yield of SiO2 NPs was produced via the chemical treatment of rice husk ash by the sol–gel method. Characteristics of the prepared SiO2 NPs were validated using different characterization techniques. Accordingly, the phase, chemical composition, morphological, and spectroscopic properties of the prepared sample were studied. The average particle size of the SiO2 NPs was found to be approximately 60–80 nm and the surface area was 78.52 m²/g. The prepared SiO2 NPs were examined as photocatalysts for the degradation of methyl orange (MO) dye under UV irradiation. It was found that the intensity of the characteristic absorption band of MO decreased gradually with exposure time increasing, which means the successful photodegradation of MO by SiO2 NPs. Moreover, the antibacterial activity of obtained SiO2 NPs was investigated by counting the coliform bacteria in the surface water using the most probable number (MPN) index method. The results revealed that the MPN of coliform bacteria untreated and treated by SiO2 NPs was estimated to be 170 CFU/100 mL and 10 CFU/100 mL, respectively, resulting in bacterial growth inhibition of 94.12%.
The Influence of Nanosilica on Properties of Cement Based on Tetracalcium Phosphate/Monetite Mixture with Addition of Magnesium Pyrophoshate
Authors: Stulajterova Radoslava , Giretova Maria , Medvecky Lubomir , Sopcak Tibor , Luptakova Lenka , Girman Vladimir
Published: November 2022

The effect of nanosilica on the microstructure setting process of tetracalcium phosphate/nanomonetite calcium phosphate cement mixture (CPC) with the addition of 5 wt% of magnesium pyrophosphate (assigned as CT5MP) and osteogenic differentiation of mesenchymal stem cells cultured in cement extracts were studied. A more compact microstructure was observed in CT5MP cement with 0.5 wt% addition of nanosilica (CT5MP1Si) due to the synergistic effect of Mg2P2O7 particles, which strengthened the cement matrix and nanosilica, which supported gradual growth and recrystallization of HAP particles to form compact agglomerates. The addition of 0.5 wt% of nanosilica to CT5MP cement caused an increase in CS from 18 to 24 MPa while the setting time increased almost twofold. It was verified that adding nanosilica to CPC cement, even in a low amount (0.5 and 1 wt% of nanosilica), positively affected the injectability of cement pastes and differentiation of cells with upregulation of osteogenic markers in cells cultured in cement extracts. Results revealed appropriate properties of these types of cement for filling bone defects.
From Light-Powered Motors, to Micro-Grippers, to Crawling Caterpillars, Snails and Beyond—Light-Responsive Oriented Polymers in Action
Authors: Rogóż Mikołaj , Dziekan Zofia , Dradrach Klaudia , Zmyślony Michał , Nałęcz-Jawecki Paweł , Grabowski Przemysław , Fabjanowicz Bartosz , Podgórska Magdalena , Kudzia Anna , Wasylczyk Piotr
Published: November 2022

“How would you build a robot, the size of a bacteria, powered by light, that would swim towards the light source, escape from it, or could be controlled by means of different light colors, intensities or polarizations?” This was the question that Professor Diederik Wiersma asked PW on a sunny spring day in 2012, when they first met at LENS—the European Laboratory of Nonlinear Spectroscopy—in Sesto Fiorentino, just outside Florence in northern Italy. It was not just a vague question, as Prof. Wiersma, then the LENS director and leader of one of its research groups, already had an idea (and an ERC grant) about how to actually make such micro-robots, using a class of light-responsive oriented polymers, liquid crystal elastomers (LCEs), combined with the most advanced fabrication technique—two-photon 3D laser photolithography. Indeed, over the next few years, the LCE technology, successfully married with the so-called direct laser writing at LENS, resulted in a 60 micrometer long walker developed in Prof. Wiersma’s group (as, surprisingly, walking at that stage proved to be easier than swimming). After completing his post-doc at LENS, PW returned to his home Faculty of Physics at the University of Warsaw, and started experimenting with LCE, both in micrometer and millimeter scales, in his newly established Photonic Nanostructure Facility. This paper is a review of how the ideas of using light-powered soft actuators in micromechanics and micro-robotics have been evolving in Warsaw over the last decade and what the outcomes have been so far.
Effect of Poling on Multicatalytic Performance of 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Sr0.3)TiO3 Ferroelectric Ceramic for Dye Degradation
Authors: Gaur Akshay , Dubey Shivam , Elqahtani Zainab Mufarreh , Ahmed Samia ben , Al-Buriahi Mohammed Sultan Abdulghaffar , Vaish Rahul , Chauhan Vishal Singh
Published: November 2022

Ferroelectric materials with a spontaneous polarization are proven to be potential multicatalysts in water remediation applications. The composition of 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Sr0.3)TiO3 (BST-BZT) was examined for photocatalysis, piezocatalysis, and piezo-photocatalysis processes by degrading an azo dye named methylene blue (MB). Generally, dis-aligned dipoles restrict the catalytic activities due to which the BST-BZT powder sample was poled by the corona poling technique. Coupled piezocatalysis and photocatalysis process, i.e., the piezo-photocatalysis process has shown maximum dye degradation. There was a significant improvement in degradation efficiency by using a poled BST-BZT sample compared to the unpoled sample in all processes, thus the results suggest an extensive scope of poled ferroelectric ceramic powder in the catalysis field.
One Dimensional Twisted Van der Waals Structures Constructed by Self-Assembling Graphene Nanoribbons on Carbon Nanotubes
Authors: Zhou Kun , Wang Liya , Wang Ruijie , Wang Chengyuan , Tang Chun
Published: November 2022

Twisted van der Waals heterostructures were recently found to possess unique physical properties, such as superconductivity in magic angle bilayer graphene. Owing to the nonhomogeneous stacking, the energy of twisted van der Waals heterostructures are often higher than their AA or AB stacking counterpart, therefore, fabricating such structures remains a great challenge in experiments. On the other hand, one dimensional (1D) coaxial van der Waals structures has less freedom to undergo phase transition, thus offer opportunity for fabricating the 1D cousin of twisted bilayer graphene. In this work, we show by molecular dynamic simulations that graphene nanoribbons can self-assemble onto the surface of carbon nanotubes driven by van der Waals interactions. By modifying the size of the carbon nanotubes or graphene nanoribbons, the resultant configurations can be controlled. Of particular interest is the formation of twisted double walled carbon nanotubes whose chiral angle difference can be tuned, including the 1.1° magic angle. Upon the longitudinal unzipping of such structures, twisted bilayer graphene nanoribbons can be obtained. As the longitudinal unzipping of carbon nanotubes is a mature technique, we expect the strategy proposed in this study to stimulate experimental efforts and promote the fast growing research in twistronics.
The Effect of Cu Addition on the Precipitation Sequence in the Al-Si-Mg-Cr Alloy
Authors: Chen Bin , Dong Liang , Hu Bin , Liu Zhenyang
Published: November 2022

In this work, the effect of Cu additives and heat treatment on the precipitation sequence of an Al-Si-Mg-Cr alloy has been systematically studied by means of advanced spherical aberration-corrected electron microscopy. Cu atoms tend to gather at the interface between the precipitates and the matrix at the beginning of the aging process. Then, Cu atoms diffuse into the precipitates. Two types of GP zones are formed in the first stage of precipitation: one is the type I GP zone and the other is the type II GP zone. The type I GP zone βCu″ evolved into the Q′ phase, while the type II GP zone evolved into the θ′ phase during the aging process. The aging sequence of the Al-Si-Mg-Cr alloy can be determined as a supersaturated solid solution (SSSS) → GP zones → β″→ β′/B′(→β). The aging sequence of the Al-7%Si-0.3%Mg-0.3%Cr-1.5%Cu alloy can be determined as a supersaturated solid solution (SSSS)→GP zone→βCu″→Q′ + θ′(→Q + θ).
Experimental Study on the Effects of Matric Suction on Shear Properties of Polypropylene Fiber Reinforced Unsaturated Clay
Authors: Wu Ruiqian , Yang Guang , Li Shaohe , Xiang Qichen
Published: November 2022

Matric suction has an important effect on the behavior of unsaturated soils, and polypropylene fibers are often used to improve soil. In order to probe into the mechanism of matric suction and fiber reinforcement, triaxial shear tests are carried out with changing matric suction and net confining pressure. Unsaturated clay in the Shaoxing section of East Zhejiang Grand Canal is selected with polypropylene fiber as a reinforcement material in the tests. The results show that the total cohesion intercept and effective internal friction angle of soil increase with the increase in matric suction, while the adsorption internal friction angle decreases gradually. Similarly, the contribution of matric suction to shear strength decreases. The total cohesion intercept is more sensitive to matric suction. As the length of fiber is 12 mm, the shear strength parameters of soil will be improved accordingly, which makes the fiber reinforcement achieve the best. The stress–strain relationship is approximately hyperbolic and strain hardening. The characteristics of strain hardening are more obvious with the increase in matric suction, and the soil specimens present plastic failure. The volumetric strain of specimen is more sensitive to the changing net confining pressure. It increases with the increase in net confining pressure, and increases linearly as the matric suction is zero. The failure modes of triaxial tests are divided into tensile failure and friction failure.
Effects of Ni and Cu Residuals on the Magnetic Properties and Microstructure of SmCo5 Magnets
Authors: Mehmood Muhammad Farhan , Eldosouky Anas , Žužek Rožman Kristina , Šturm Sašo
Published: November 2022

The effect of Ni/Cu-coating residuals on the magnetic properties and microstructures of samarium–cobalt (SmCo5) magnets was studied. SmCo5 magnets with 0.0, 0.5, 1.0, 2.0, 3.0 and 4.0 wt.% of added Ni/Cu (85 wt.% Ni/15 wt.% Cu) were prepared using a conventional sintering route. The magnetic properties of the magnets were found to be consistent up to 2 wt.% Ni/Cu. Any further increase in the Ni/Cu content resulted in a significant reduction in the magnetic properties, to lower than values that would be commercially acceptable. SEM/EDS studies showed that two major phases, i.e., the SmCo5 matrix phase and Sm2O3 were present in all the sintered SmCo5 magnets. The presence of Sm2Co7 as a minor phase fraction was detected in the sintered SmCo5 magnets containing up to 2 wt.% Ni/Cu. A 2 wt.% Ni/Cu addition to magnets resulted in the presence of two new phases with compositions close to SmCo and Sm2Co17 in addition to SmCo5 and Sm2O3 as major phases in the SEM-observed microstructure. These newly formed phases are present in small fractions and are presumably homogenously distributed at the grain boundaries of the magnets. As they are known to act as nucleation sites for reverse magnetic domains, they effectively reduce the intrinsic grain boundary magnetic strength, leading to a drop in the coercivity. We concluded that the sintered SmCo5 magnets could be recycled with up to 2 wt.% Ni/Cu as a residual from the coating under our sintering and heat treatment conditions.
On the Theory of Magnetoelectric Coupling in Fe2Mo3O8
Authors: Eremin Mikhail , Vasin Kirill , Nurmukhametov Alexey
Published: November 2022

In the last decade, Fe2Mo3O8 was recognized for a giant magnetoelectric effect, the origin of which is still not clear. In the present paper, we contribute to the microscopic theory of the magnetoelectric coupling in this compound. Using crystal field theory and the molecular field approximation, we calculated the low-lying energy spectrum for iron ions and their interaction with electric and magnetic fields. Classical ionic contribution to the electric polarization related to the ionic shifts is also estimated. It is found that the electronic and ionic contributions to the electric polarization are comparable and these mechanisms support each other at T<TN. The suggested electronic mechanism provides insight into the nature of huge jumps in polarization upon phase transitions from paramagnetic (PM) to antiferromagnetic (AFM) and then to ferrimagnetic (FRM) states under an applied external magnetic field as well as the large differential magnetoelectric coefficient.
Use of Neural Networks for Lifetime Analysis of Teeming Ladles
Authors: Jančar Dalibor , Machů Mario , Velička Marek , Tvardek Petr , Kocián Leoš , Vlček Jozef
Published: November 2022

When describing the behaviour and modelling of real systems, which are characterized by considerable complexity, great difficulty, and often the impossibility of their formal mathematical description, and whose operational monitoring and measurement are difficult, conventional analytical–statistical models run into the limits of their use. The application of these models leads to necessary simplifications, which cause insufficient adequacy of the resulting mathematical description. In such cases, it is appropriate for modelling to use the methods brought by a new scientific discipline—artificial intelligence. Artificial intelligence provides very promising tools for describing and controlling complex systems. The method of neural networks was chosen for the analysis of the lifetime of the teeming ladle. Artificial neural networks are mathematical models that approximate non-linear functions of an arbitrary waveform. The advantage of neural networks is their ability to generalize the dependencies between individual quantities by learning the presented patterns. This property of a neural network is referred to as generalization. Their use is suitable for processing complex problems where the dependencies between individual quantities are not exactly known.
(Cr1−xAlx)N Coating Deposition by Short-Pulse High-Power Dual Magnetron Sputtering
Authors: Grenadyorov Alexander , Oskirko Vladimir , Zakharov Alexander , Oskomov Konstantin , Solovyev Andrey
Published: November 2022

The paper deals with the (Cr1−xAlx)N coating containing 17 to 54 % Al which is deposited on AISI 430 stainless steel stationary substrates by short-pulse high-power dual magnetron sputtering of Al and Cr targets. The Al/Cr ratio in the coating depends on the substrate position relative to magnetrons. It is shown that the higher Al content in the (Cr1−xAlx)N coating improves its hardness from 17 to 28 GPa. Regardless of the Al content, the (Cr1−xAlx)N coating manifests a low wear rate, namely (4.1–7.8) × 10−9 and (3.9–5.3) × 10−7 mm3N−1m−1 in using metallic (100Cr6) and ceramic (Al2O3) counter bodies, respectively. In addition, this coating possesses the friction coefficient 0.4–0.7 and adhesive strength quality HF1 and HF2 indicating good interfacial adhesion according to the Daimler-Benz Rockwell-C adhesion test.
Optimization of Sputtering Process for Medium Entropy Alloy Nanotwinned CoCrFeNi Thin Films by Taguchi Method
Authors: Zhong Jing-Yi , Wang Jian-Jie , Ouyang Fan-Yi
Published: November 2022

We demonstrate a systematic study optimizing the properties of CoCrFeNi medium entropy alloy (MEA) thin films by tuning the deposition parameters of the pulsed direct current (DC) magnetron sputtering process. The chemical composition and microstructure of thin films were studied with energy dispersive X-ray spectroscopy (EDS), an X-ray diffractometer (XRD) and a transmission electron microscope (TEM). Abundant nanotwins and the dual face-centered cubic−hexagonal close-packed (FCC-HCP) phases were formed in some specimens. The Taguchi experimental method and analysis of variance (ANOVA) were applied to find the optimized parameters. The control factors are five deposition parameters: substrate bias, substrate temperature, working pressure, rotation speed and pulsed frequency. According to the signal-to-noise ratio results, the optimized parameters for low electrical resistivity (98.2 ± 0.8 μΩ·cm), low surface roughness (0.5 ± 0.1 nm) and high hardness (9.3 ± 0.2 GPa) were achieved and verified with confirmed experiments.
Effect of Pretreatment with Acids on the N-Functionalization of Carbon Nanofibers Using Melamine
Authors: Maksimova Tatyana A. , Mishakov Ilya V. , Bauman Yury I. , Ayupov Artem B. , Mel’gunov Maksim S. , Dmitrachkov Aleksey M. , Nartova Anna V. , Stoyanovskii Vladimir O. , Vedyagin Aleksey A.
Published: November 2022

Nowadays, N-functionalized carbon nanomaterials attract a growing interest. The use of melamine as a functionalizing agent looks prospective from environmental and cost points of view. Moreover, the melamine molecule contains a high amount of nitrogen with an atomic ratio C/N of 1/2. In present work, the initial carbon nanofibers (CNFs) were synthesized via catalytic pyrolysis of ethylene over microdispersed Ni–Cu alloy. The CNF materials were pretreated with 12% hydrochloric acid or with a mixture of concentrated nitric and sulfuric acids, which allowed etching of the metals from the fibers and oxidizing of the fibers’ surface. Finally, the CNFs were N-functionalized via their impregnation with a melamine solution and thermolysis in an inert atmosphere. According to the microscopic data, the initial structure of the CNFs remained the same after the pretreatment and post-functionalization procedures. At the same time, the surface of the N-functionalized CNFs became more defective. The textural properties of the materials were also affected. In the case of the oxidative treatment with a mixture of acids, the highest content of the surface oxygen of 11.8% was registered by X-ray photoelectron spectroscopy. The amount of nitrogen introduced during the post-functionalization of CNFs with melamine increased from 1.4 to 4.3%. Along with this, the surface oxygen concentration diminished to 6.4%.
Effect of Mechanical Vibration on the Mechanical Properties and Solidification Feeding in Low-Pressure Sand Casting of Al-Cu-Mn-Ti Alloy
Authors: Chen Wei , Wu Shiping , Wang Rujia
Published: November 2022

The shrinkage defects of Al-Cu-Mn-Ti alloy seriously hinder its application in high-performance engineering. In this study, mechanical vibration was introduced to low-pressure sand casting (LPSC) by a waveguide rod to eliminate shrinkage defects and improve mechanical properties. Four LPSC castings were performed by changing the solidification conditions: 20 kPa solidification pressure without and with 14 Hz vibration and 40 kPa without and with 24 Hz (the natural frequency of a casting system) vibration. The shrinkage defects, microstructures, and mechanical tensile properties at room temperature and at 2 mm/min tensile rate were investigated. X-ray detections showed that applying vibration was more effective than increasing solidification pressure in improving solidification feeding, while the most effective method was applying both simultaneously, which eliminated the shrinkage defects and increased the density by 2.7%. Microstructures exhibited that the average size of primary α-Al grains were reduced by 29.5%; mechanical tests showed that the ultimate tensile strength and the elongation increased by 21.7% and 7.8%, respectively, by applying vibration and increasing the solidification pressure simultaneously, as compared to the casting with 20 kPa solidification pressure without vibration. Mechanical vibration was conducive to mass feeding by refining the primary grains, to interdendritic feeding by reducing the threshold pressure gradient, and to burst feeding by collapsing the barrier.
Experimental Analysis of Nano-Enhanced Phase-Change Material with Different Configurations of Heat Sinks
Authors: Fayyaz Hamza , Hussain Abid , Ali Imran , Shahid Hanzla , Ali Hafiz Muhammad
Published: November 2022

The demand for high-performance and compact electronic devices has been increasing day by day. Due to their compactness, excessive heat is generated, causing a decrease in efficiency and life. Thermal management of electronic components is crucial for maintaining excessive heat within the limit. This experimental research focuses on the combined effect of nano-enhanced phase-change material (NePCM) with different configurations of heat sinks for cooling electronic devices. Multi-walled carbon nanotubes (MWCNTs) are used as nanoparticles with concentrations of 3 wt% and 6 wt%, RT-42 as the phase-change material (PCM), and aluminum as the pin fin heat sink material. Different configurations of the heat sink, such as circular, square, and triangular pin fins, are used against the fixed volume fraction of the fins. It is found that the square configuration has the highest heat transfer with and without PCM. A maximum base temperature reduction of 24.01% was observed in square pin fins with RT-42 as PCM. At 6 wt% of NePCM, the maximum base temperature lessened by 25.83% in the case of a circular pin fin. It is concluded from the results that a circular pin fin with NePCM is effective for base temperature reduction, and all fin configurations with NePCM collectively reduce the heat sink base temperature.
Effect of BASC and BASCA Heat Treatment on Microstructure and Mechanical Properties of TC10 Titanium Alloy
Authors: Zhang Mingyu , Yun Xinbing , Fu Hongwang
Published: November 2022

The purpose of this study is to investigate two new heat treatment processes on the mechanical properties of TC10 titanium alloy. By changing the β annealing temperature, the variation in microstructure and mechanical properties of TC10 titanium alloy were investigated. The results showed that with the increase in β annealing temperature the microstructure type changes from an equiaxed structure to a lamellar structure. The strength of the alloy then increases firstly, followed by a decrease, while the plasticity decreases all the time. Microstructure observation revealed that the alloy is uniformly composed of α phase and β phase after the two processes. In addition, it was found that the fracture morphology of the equiaxed structure is mainly dimples, showing ductile fracture characteristics, while the fracture morphology of lamellar microstructure is mainly crystalline, showing brittle fracture characteristics. These results indicated that reasonable β annealing temperature can be set according to different requirements to obtain different types of microstructure and mechanical properties, which expands the application field of TC10 titanium alloy.
Modelling of Magnetic Stray Fields in Multilayer Magnetic Films with In-Plane or Perpendicular Anisotropy
Authors: Zhou Sai , Wang Yiyue , Liu Yaowen
Published: November 2022

The magnetic stray field is an unavoidable consequence of magnetic multilayers, which may have a significant influence on the performance of spintronic devices. Based on Maxwell’s magnetostatics theory, here we numerically calculated the distributions of magnetic stray fields and self-demagnetizing fields in a series of patterned multilayer thin-film structures with either an in-plane or a perpendicularly magnetized ferromagnetic layer. The stray field above the ferromagnetic layer is inhomogeneous, showing the dramatic changes near the sample edge, but the uniformity in the center region could be improved with the increasing sample size. The stray field strength tends to zero for large samples, increases with the increase in the hard-layer thickness, and decreases with the increase in the distance D away from the ferromagnetic layer. In the multilayer samples, the separately simulated stray field and self-demagnetizing field within the soft layer agree well with the classic magnetostatic relationship of B=μ0(Hd+M). For the in-plane magnetized trilayer sample, the magnetic-flux density within the soft ferromagnetic layer slightly decreases in the antiparallel magnetization alignment and increases in the parallel alignment state with the increase in the intermediate non-magnetic-layer thickness. In contrast, for the sample with the perpendicular magnetization, the magnetic-flux density decreases as the non-magnetic layer is thickened for both the antiparallel and parallel state. This study may provide a theoretical basis for the design of thin-film spintronic devices.
A New Rough Set Classifier for Numerical Data Based on Reflexive and Antisymmetric Relations
Authors: Ishii Yoshie , Iwao Koki , Kinoshita Tsuguki
Published: November 2022

The grade-added rough set (GRS) approach is an extension of the rough set theory proposed by Pawlak to deal with numerical data. However, the GRS has problems with overtraining, unclassified and unnatural results. In this study, we propose a new approach called the directional neighborhood rough set (DNRS) approach to solve the problems of the GRS. The information granules in the DNRS are based on reflexive and antisymmetric relations. Following these relations, new lower and upper approximations are defined. Based on these definitions, we developed a classifier with a three-step algorithm, including DN-lower approximation classification, DN-upper approximation classification, and exceptional processing. Three experiments were conducted using the University of California Irvine (UCI)’s machine learning dataset to demonstrate the effect of each step in the DNRS model, overcoming the problems of the GRS, and achieving more accurate classifiers. The results showed that when the number of dimensions is reduced and both the lower and upper approximation algorithms are used, the DNRS model is more efficient than when the number of dimensions is large. Additionally, it was shown that the DNRS solves the problems of the GRS and the DNRS model is as accurate as existing classifiers.
Computing Sharp Bounds of Metric Based Fractional Dimensions for the Sierpinski Networks
Authors: Fatima Arooba , Alamer Ahmed , Javaid Muhammad
Published: November 2022

The concept of metric dimension is widely applied to solve various problems in the different fields of computer science and chemistry, such as computer networking, integer programming, robot navigation, and the formation of chemical structuring. In this article, the local fractional metric dimension (LFMD) of the cycle-based Sierpinski networks is computed with the help of its local resolving neighborhoods of all the adjacent pairs of vertices. In addition, the boundedness of LFMD is also examined as the order of the Sierpinski networks approaches infinity.
Interactive Impacts of Overconfidence and Competitive Preference on Closed-Loop Supply Chain Performance
Authors: Xu Hao , Gao Kaiye , Chi Yuanying , Chen Yahui , Peng Rui
Published: November 2022

As sustainable development becomes an important goal for all industries, the study of closed-loop supply chains has gradually become a priority. Most of the previous studies on closed-loop supply chains are based on simple and single market conditions, which cannot analyze the real situation well. In this paper, two common behavioral preferences in the market, overconfidence and competitive preference, are incorporated into the study of closed-loop supply chains to investigate how the overconfidence of retailers and the competitive preference of manufacturers jointly affect the decisions and interests of both parties in closed-loop supply chains under different dominant models. It is concluded that in terms of pricing, while the wholesale price increases in the competitive preference, the reselling price in fact decreases when the retailer’s overconfidence level is of a middle level; in terms of recycling, the pursuit of high profits by monopolistic manufacturers is not conducive to recycling quantity in the secondary supply chain with recycling; in terms of profits, in a manufacturer-led model, the profits of all sides in the closed-loop supply chain, including the manufacturer itself, sometimes diminish as the manufacturer’s competitive preference behavior becomes more intense.
Neural Subspace Learning for Surface Defect Detection
Authors: Liu Bin , Chen Weifeng , Li Bo , Liu Xiuping
Published: November 2022

Surface defect inspection is a key technique in industrial product assessments. Compared with other visual applications, industrial defect inspection suffers from a small sample problem and a lack of labeled data. Therefore, conventional deep-learning methods depending on huge supervised samples cannot be directly generalized to this task. To deal with the lack of labeled data, unsupervised subspace learning provides more clues for the task of defect inspection. However, conventional subspace learning methods focus on studying the linear subspace structure. In order to explore the nonlinear manifold structure, a novel neural subspace learning algorithm is proposed by substituting linear operators with nonlinear neural networks. The low-rank property of the latent space is approximated by limiting the dimensions of the encoded feature, and the sparse coding property is simulated by quantized autoencoding. To overcome the small sample problem, a novel data augmentation strategy called thin-plate-spline deformation is proposed. Compared with the rigid transformation methods used in previous literature, our strategy could generate more reliable training samples. Experiments on real-world datasets demonstrate that our method achieves state-of-the-art performance compared with unsupervised methods. More importantly, the proposed method is competitive and has a better generalization capability compared with supervised methods based on deep learning techniques.