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Peripheral neural regeneration is an interesting and challenging field. The aim of this study was to investigate the interactions of neural-like PC12 cells and Poly-D-Lysine (PDL)-coated 3D-printed polycaprolactone (PCL) scaffolds with different inner diameters of half tubular array (HTA) (0, 200, 300, and 400 μm), respectively. This study used the fused deposition modeling (FDM) technique with 3D-printing to fabricate the thermoplastic polymer. Scaffold properties were measured by mechanical testing, and coating quality was observed under a scanning electron microscope (SEM). PC12 cell biocompatibility was examined by an MTT assay. Cell differentiation was evaluated by immunofluorescence staining. The cell viability of PC12 cells on PDL-coated PCL scaffolds with a 200-μm inner diameter of HTA was shown with significant differences (∗ P < 0.05, ∗∗ P < 0.01, ∗∗∗ P < 0.001) than other PCL groups at all experimental dates. The SEM observation showed that PDL-coated PCL scaffolds with 200-μm inner diameters of HTA promoted cell adhesion. An immunofluorescence staining of PC12 cells on the PDL-coated PCL scaffold with a 200-μm inner diameter of the HTA group showed that it stimulated PC12 cells for neurite formation much better than the other groups. A PDL-coated PCL scaffold with a 200-μm inner diameter of HTA can promote the growth and differentiation of PC12 cells better than other groups. It indicated that PDL-coated PCL scaffolds with a 200-μm inner diameter HTA can be used for further neural regeneration application. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effects from the memory-triple (MT) heat treatment on the fatigue resistance of the Reciproc by comparison with the file systems of same geometry. Reciproc files subjected to MT heat treatment technology were designated as Group RMT and were compared with the original Reciproc (Group REC) and Reciproc Blue (Group REB). Each NiTi file from 3 groups (n = 15) was operated reciprocally with a repetitive up-and-down movement in the curved canal with 4 mm of pecking distance inside of the simulated canal at body temperature. When each file fractured, the time until fracture was recorded. The length of the fractured fragment was measured. Fractured fragments were observed under scanning electron microscope (SEM) to evaluate the topographic features of the surface. Differential scanning calorimetry (DSC) analysis was performed to estimate phase transformation temperatures. One-way analysis of variance and Duncan post hoc comparison were applied to compare among the groups at a significance level of 95%. RMT showed significantly higher fracture resistance (P <.05), whereas there was no difference in fatigue resistance between REC and REB. SEM examination showed the files from the 3 groups had similar topographic features. RMT showed a peak of austenite peak (A p) at a temperature (52°C) higher than body temperature, whereas REC and REB showed A p at 37 and 32°C, respectively. Under the condition of this study, the new heat treatment technique of MT technology could enhance the fatigue fracture resistance of the reciprocating files made of M-wire and Blue-wire. [ABSTRACT FROM AUTHOR]

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the routine maintenance of each main pump in the oil transmission station plant, abnormal erosion wear was found at the flushing port of the mechanical seal of Sulzer pump casing. For the sake of stable and safe unit operation, this study explored the mechanism and process of erosion formation in the pump casing at the microscopic level using SEM (scanning electron microscope) and EDS (energy dispersive spectrometer) techniques. And ANSYS Fluent was used to numerically simulate the unconventional turbulent flow in the special location of Sulzer pump to obtain its flow field characteristics. The trajectory tracking of solid phase particles based on Finnie erosion model was also carried out to obtain the influence law of different particle sizes on the wear degree of each area of the pump casing, and to point out the influence of the motion behavior of particles at the flushing port position on the erosion. The results show that there is unconventional turbulence in the flushing port of the Sulzer pump mechanical seal, and the solid particles are affected by turbulent diffusion and fluid adhesion, and some particles deviate from the velocity direction and continuously impact the surface of the pump casing, which is the direct cause of the erosion wear here. By optimizing the location of the flushing port, severe erosion wear at the flushing port can be avoided. This study can provide guidance and recommendations for the production, operational stability and wear protection of Sulzer pumps. [ABSTRACT FROM AUTHOR]

Foam stability tests were performed using sodium dodecyl sulfate (SDS) surfactant and SiO2 nanoparticles as foaming system at different asphaltene concentrations, and the half-life of CO2 foam was measured. The mechanism of foam stability reduction in the presence of asphaltene was analyzed by scanning electron microscope (SEM), UV adsorption spectrophotometric concentration measurement and Zeta potential measurement. When the mass ratio of synthetic oil to foam-formation suspension was 1:9 and the asphaltene mass fraction increased from 0 to 15%, the half-life of SDS-stabilized foams decreased from 751 s to 239 s, and the half-life of SDS/silica-stabilized foams decreased from 912 s to 298 s. When the mass ratio of synthetic oil to foam-formation suspension was 2:8 and the asphaltene mass fraction increased from 0 to 15%, the half-life of SDS-stabilized foams decreased from 526 s to 171 s, and the half-life of SDS/silica-stabilized foams decreased from 660 s to 205 s. In addition, due to asphaltene-SDS/silica interaction in the aqueous phase, the absolute value of Zeta potential decreases, and the surface charges of particles reduce, leading to the reduction of repulsive forces between two interfaces of thin liquid film, which in turn, damages the foam stability. [ABSTRACT FROM AUTHOR]

The objective of the study was to evaluate the effects of dentin deproteinization protocols for post space using different formulations containing sodium hypochlorite before fiber post cementation with self-adhesive resinous cement. The groups were divided according to the irrigation protocol (DWC, SHS, SHT and SHG). The residue cleanliness, bond strength, adhesive failure pattern, and tag formation at the adhesive interface between the self-adhesive cement and the dentin were evaluated. For this, analysis in scanning electron microscope, push-out test and confocal laser scanning microscopy were performed. The SHT protocol showed the highest residue cleanliness on the dentin surface of the post space (p<0.05). In addition, SHT protocol showed highest bond strength and tag formation in the cervical and middle thirds (p<0.05). Dentin deproteinization with sodium hypochlorite with surfactant provided the best dentin cleaning of residues, bond strength and tag formation after cementation of the fiber post with self-adhesive cement. [ABSTRACT FROM AUTHOR]

3D-printing technology is an important tool for the bone tissue engineering (BTE). The aim of this study was to investigate the interaction of polycaprolactone (PCL) scaffolds and modified mesh PCL coated with beta TCP (PCL/β-TCP) scaffolds with MG-63. This study used the fused deposition modeling (FDM) technique with the 3D printing technique to fabricate the thermoplastic polymer and composite scaffolds. Scaffold structure and coating quality were observed under a scanning electron microscope (SEM). MG-63 cells were injected and attached to the mesh-manufactured PCL scaffolds. The biocompatibility of mesh structured PCL and PCL/β-TCP scaffolds could be examined by measuring the viability of MG-63 cells of MTT assay. Bone cell differentiation was evaluated ALP activity by mineralization assay. The results showed that both mesh PCL scaffolds and PCL/β-TCP scaffolds were non-toxic to the cells. The ALP activities of cells in PCL/β-TCP scaffolds groups were significant differences and better than PCL groups in all groups at all experimental dates. The mineralization process was time-dependent, and significantly higher mineralization of osteosarcoma cells was observed on PCL/β-TCP scaffolds at experimental dates. We concluded that both meshes structured PCL and PCL/β-TCP scaffolds could promote the MG-63 cell growth, and PCL/β-TCP was better than the PCL scaffolds for the outcome of MG63 cell differentiation and mineralization. [ABSTRACT FROM AUTHOR]

The presence of restorative material between resin cement and the light-curing unit can reduce light transmission. This study aimed to evaluate the effect of the light-blocking effect of zirconia crown on shear bond strength (SBS) between three dual-cured resin cements and the zirconia surface. Sixty zirconia specimens were prepared and divided into three groups according to the type of resin cement [RXU (RelyX Ultimate); SC2 (SmartCem2); MEC (Maxcem Elite Chroma)]. Each group was further divided into two subgroups, with or without a 1-mm-thick zirconia crown (n = 10). The specimens were light-cured from five different directions for 20 s each. All specimens were thermocycled 5000 times and subjected to SBS testing, followed by scanning electron microscope examination. The presence of a 1-mm-thick zirconia crown had no significant effect on the SBS in all resin cements. However, the SBS was significantly affected by type of resin cement. RXU showed the highest SBS (8.35 MPa with crown; 8.57 MPa without crown), followed by SC2 (5.48 MPa with crown; 5.57 without crown) and then MEC (3.37 MPa with crown; 4.04 MPa without crown. Fractured surfaces exhibited varying degrees of mixed failure patterns. A 1-mm-thick zirconia crown material between the light source and the dual-cured resin cement did not significantly influence the SBS of the resin cements on the zirconia substrates. RXU exhibited the highest SBS regardless of zirconia crown coverage. With sufficient light-curing, dual-cured resin cements can be a good choice for zirconia crown cementation. [ABSTRACT FROM AUTHOR]

Fine-grained magnesium was tested under stress-controlled tension-tension cyclic loading at -30 °C and the tested sample was observed using scanning electron microscope and electron backscatter diffraction to explore the fatigue behavior and crack propagation. The fatigue data showed that the material experienced cyclic softening followed by cyclic hardening before the final fracture failure. The microscopic observations demonstrated that the cracks were almost perpendicular to the loading direction with some zigzags and the cracks progressed along both small angle grain boundaries and large angle grain boundaries. Although the cracks were mainly propagated along large angle grain boundaries, the value of grain boundary angle was not the primary factor to determine the crack propagation direction. The local residual strain from the rolling process was released due to the crack propagation and there was more strain relaxation at regions closer to the cracks. [ABSTRACT FROM AUTHOR]

Ureteral stricture caused by holmium: YAG laser lithotripsy is one of the most challenging issues for urologists. Currently, evidence for rapamycin application in reducing ureterostenosis is not sufficient. This study aimed to assess the inhibition of ureteral stricture of rapamycin-eluting stents in vitro and in vivo. A bilayered drug-eluting ureteral stent consisted of drug blending with poly (lactic-co-glycolic acid) (PU/drug stent), which was over-layered by polycaprolactone (PCL) by ultrasonic atomizing spraying. Stent morphology was observed by scanning electron microscope. A kidney-ureter-bladder model was established to simulate the stents-releasing condition, and high-performance liquid chromatography was used to measure the drug release rate. The inhibitory proliferation was detected by CCK-8. The bladder of rats was injured through electro tome, and stents were implanted for 7, 14, and 28 days. The effects of drug-eluting stents was investigated by hematoxylin-eosin staining, immunofluorescence staining, real-time quantitative polymerase chain reaction and western blot. The bilayered stents could block the burst loss of the drug and maintained a sustained delivery period because of the 5.3 μm thickness of the PCL layer. The relative growth rates of cells plotted inhibitory effect on the proliferation of human urethral scar fibroblast cells. For in vivo results of 28 days, the bilayered stent maintained structural integrity and induced less deposition of crystals, thinner and less lamina propria connective tissues were formed, and α-SMA and TGF-β1 were downregulated. Bilayered rapamycin-eluting stent is significantly effective in alleviating fibrosis in in vitro and in vivo models. The occurrence of ureteral stricture resulting from holmium: YAG laser lithotripsy presents a significant challenge for urologists. Traditional double J stents have not been proven to offer a shorter indwelling time or improved inhibition of tissue blocking. While drug-eluting stents containing rapamycin, paclitaxel, and other substances have been extensively used in treating artery stenosis, there is insufficient evidence supporting their application in reducing ureterostenosis. Consequently, a biodegradable polymer ureteric scaffold incorporating rapamycin was fabricated in this study, employing ultrasonic atomization spraying technology to optimize the bilayers composed of 75/25 poly (lactic-co-glycolic acid) (PLGA) and polycaprolactone (PCL). The efficacy of the scaffold was subsequently confirmed through in vitro and in vivo experiments. [Display omitted] [ABSTRACT FROM AUTHOR]

Background Cellulase is an important bioprocessing enzyme used in various industries. This study was conducted with the aim of improving the biodegradation activity of cellulase obtained from the Bacillus subtilis AG-PQ strain. For this purpose, AgO and FeO NPs were fabricated using AgNO3 and FeSO4⋅7H2O salt respectively through a hydrothermal method based on five major steps; selection of research-grade materials, optimization of temperature, pH, centrifuge, sample washed with distilled water, dry completely in the oven at the optimized temperature and finally ground for characterization. The synthesized NPs were characterized by scanning electron microscope (SEM), energy dispersive X-ray (EDX), and X-ray diffraction (XRD) to confirm the morphology, elemental composition, and structure of the sample respectively. The diameter of the NPs was recorded through SEM which lay in the range of 70-95 nm. Results Cultural parameters were optimized to achieve better cellulase production, where incubation time of 56 h, inoculum size of 5%, 1% coconut cake, 0.43% ammonium nitrate, pH 8, and 37 °C temperature were found optimal. The enhancing effect of AgO NPs was observed on cellulase activity (57.804 U/ml/min) at 50 ppm concentration while FeO NPs exhibited an inhibitory effect on cellulase activity at all concentrations. Molecular docking analysis was also performed to understand the underlying mechanism of improved enzymatic activity by nanocatalysts. Conclusion This study authenticates AgO NPs as better nanocatalysts for improved thermostable cellulase biodegradation activity with the extraordinary capability to be potentially utilized in bioethanol production. [ABSTRACT FROM AUTHOR]

As a kind of natural fiber, ramie fiber has distinctive advantages in textile application, but the application is limited due to the traditional degumming mode. Compared with the traditional degumming process, the microbial degumming process has many advantages. To obtain the optimal conditions for degumming ramie with Bacillus subtilis DZ5 (BSDZ5), a combined statistical approach of orthogonal array design (OAD) and response surface methodology (RSM) was used. The influences of initial pH of the bacteria medium, culture temperature, shaking speed, degumming time and inoculum size on submerged fermentation degumming were evaluated by using fractional factorial design. The main factors in the analysis were culture temperature, shaking speed and initial pH. The residual gum mass fraction was used as the optimization index, and the optimal conditions for degumming were determined by central composite design and RSM. Thus with only a limited number of experiments, an optimal ramie microbial degumming condition was found as the culture temperature of 40°C, the initial pH in the culture medium of 8. 5, the shaking speed of 205 r / min, the degumming time of 96 h and the inoculum size of 5%. After microbial degumming of ramie under the optimal conditions, there was only 10. 6% residual gum by mass in the fiber. In addition, the effective degumming of BSDZ5 was also confirmed by a scanning electron microscope (SEM). [ABSTRACT FROM AUTHOR]

Copyright of Science of Sintering is the property of National Library of Serbia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One of the challenges in adhesive ceramic restorations is deterioration of tooth-cement-ceramic interfaces. This study was to quantitatively investigate lipopolysaccharide (LPS) penetration through adhesive ceramic restorations. Standardized holes were formed on ceramic (IPS Empress CAD, Ivoclar Vivadent) and human dentin discs. Prepared discs were randomly assigned to experimental groups (n = 6/group): SC, self-adhesive resin cement (SmartCem 2, Dentsply Sirona) bonded to ceramic discs; ST, self-adhesive resin cement bonded to dentin discs; VC, etch-and-rinse resin cement (Variolink II, Ivoclar Vivadent AG) bonded to ceramic discs; VT, etch-and-rinse resin cement bonded to dentin discs. The specimens underwent thermocycling (10,000 cycles; 5–55 °C) then LPS penetration test until 5-weeks. A mixed effect analysis using R statistical language was performed for data analysis. Dentin and ceramic bonded with etch-and-rinse resin cements (groups VT and VC) showed significantly less penetration than those with self-adhesive resin cement (groups ST and SC) (P < 0.05). ST showed significantly lower penetration than SC (P < 0.05), that showed similar penetration with positive control (P > 0.05). VC showed minimal penetration during observed time of period (P < 0.05). Scanning electron microscope observations showed different interfacial characteristics among the groups. Within the limitation of this study, etch-and-rinse resin cement showed less LPS penetration than self-adhesive resin cement on both ceramic and dentin surfaces. [ABSTRACT FROM AUTHOR]

Cosmetics for perming hair are commonly used but have negative impacts on hair fibers. Repairing damaged hair with conditioners, hair oil, and hair masks can provide relief but cannot prevent injuries. Recent research has shown that proteins and amino acids can remodel hair's disulfide bonds. However, the permeation ability of proteins is limited, and amino acids may disrupt the secondary structure of hair keratins. Our study demonstrates that peptides can be safely, efficiently, and promisingly used for hair perming. A bioinspired peptide, PepACS (PepA-PepC-SPB), was designed through bioinformatics. It can interact with keratin's sulfhydryl group in situ to remodel disulfide bonds without affecting hair fiber's tensile properties. The potential of PepACS to repair cuticle injuries is also observed through scanning electron microscope visualization. Besides, linking PepACS with mCherry enables hair dyeing. This research suggests that biomaterials can be applied in the hair care industry. Chemical perming products can have negative impacts on people's health and hair fibers, making it essential to explore alternative methods. Peptides treatment is a promising option, but synthesizing sulfur-rich short peptides for hair perming has not been demonstrated before. In this paper, we utilized bioinformatics to design bio-inspired peptides that can interact with hair keratins and form curled shapes. Our study demonstrates that bioinformatics tools can be utilized to design bioinspired peptides with unique functions. Sulfur-rich short peptides can be heterologously expressed with fusion strategies, and PepACS can securely bind hair fibers through disulfide bonds. Importantly, perming hair with 0.01% PepACS maintains the mechanical properties of hair, and dyeing hair with the fusion protein PepACS_mCh can be facilitated by ethanol. These findings suggest that the strategy of perming and dyeing hair through peptides is non-injurious, and the peptides used for repairing hair damage show tremendous potential. [Display omitted] [ABSTRACT FROM AUTHOR]

The objective of this research is to investigate different chemical pretreatment methods to reduce the lignin and hemicellulose content of Omani Prosopis Juliflora. The pretreated wood will then be acid hydrolyzed to convert the cellulose content to sugar. Four types of pretreatment methods were employed, namely: Alkaline pretreatment (Method I), Alkaline + Hydrogen peroxide pretreatment (Method II), Alkaline + Hydrogen peroxide + acid-chlorite pretreatment (Method III) and Alkaline + H 2 O 2 + Acid-chlorite + bicarbonate pretreatment (Method IV). The effectiveness of each pretreatment method was assessed by measuring lignin, hemicellulose, and cellulose contents and the crystallinity index (CrI) using X-ray diffraction (XRD) analysis. The results were further assessed by taking images of the wood samples after each pretreatment step using Scanning Electron Microscope (SEM). The results showed that the CrI increased from 51% for the untreated samples to 61%, 65%, 68% and 73.2% after treating with Method I, II, III and IV, respectively. Measuring the cellulose, hemicellulose and lignin contents showed that the effectiveness of the methods in ascending order was Method I < Method II < Method III < Method IV. The pretreated wood samples by method IV were acid hydrolyzed. The effect of acid type, namely: H 2 SO 4 , HNO 3 , HCl and H 3 PO 4 , concentration and hydrolysis time on the %conversion of cellulose to sugar was investigated. The results revealed that H 2 SO 4 was the most effective acid, whereas H 3 PO 4 was the weakest. The efficiency of the tested acids follows the following order: H 2 SO 4 > HNO 3 > HCL > H 3 PO 4. For all acids tested, the %conversion of cellulose to reducing sugar as a function of time increases linearly till t = 90 min, after which no change in the %conversion was obtained. Investigating the effect of acid concentration showed that as the concentration increases, the %conversion increases too. Upon increasing acid concentration from 1% to 10%, the %conversion increases from 12% to 62% for H 2 SO 4 , from 5% to 43% for HNO 3 , from 0% to 47% for HCl, and from 5% to 34% for H 3 PO 4. [ABSTRACT FROM AUTHOR]

The disposal of lake sediment is a major problem in dredging and lakeside construction projects. Due to its poor mechanical properties and contamination, sediment is difficult to use directly in resource applications. Previous research has found that alkali-activated reactions can improve the mechanical properties of silicon- and aluminum–rich solid waste. In this study, the basic physical and mechanical properties of dried sediment from a lake in Wuhan, China, were analyzed. Orthogonal tests, compressive strength measurements, and X-ray diffraction spectrum and scanning electron microscope analyses were used to investigate the solidification effects of three types of alkaline materials used alone or in combination with the lake sediment: straw ash, calcium lime, and sodium silicate. In the single-doped samples, calcium lime had the best curing effect, with a maximum seven-day compressive strength of 1.31 MPa (190 psi). When the compound-doped samples were cured to seven days, the maximum compressive strength was 7.18 MPa (1040 psi). Furthermore, with the compound-doped materials, sediment solidification was aided by suitably alkaline conditions and large quantities of active silicon-calcium components. As a result, the microstructures of the cured compound-doped samples were more compact and their overall mechanical properties were greatly improved. [ABSTRACT FROM AUTHOR]

This research investigates the tribological characteristics and sustainability of WS2 deposited Al 6061-T6 surface under dry sliding conditions and optimizes the wear parameters to enhance the tribological behaviour and discuss its sustainability. The experiment used the Box–Behnken design, which examines the effective interaction between dry sliding parameters and specific wear rate (SWR) and friction coefficient (COF). By varying the load (L), sliding velocity (V) and distance (D), the wear behaviour of WS2 deposition against EN 31 steel was examined through the pin-on-disc experiment. Grooving, debris formation, polishing, tribolayer, ploughing, transfer material, smearing, delamination and pitting are observed through scanning electron microscope (SEM) analysis. For optimum conditions, SEM with energy dispersive spectroscopy was utilized to characterize the worn surface, and X-Ray diffraction (XRD) patterns confirmed the phases of W, WO3, WS2, Al, AlO, Al2S3 and Al4C3. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the improvement of selected mechanical properties of a resin-modified glass-ionomer cement (RMGIC) with a discontinuous short E glass fiber flowable resin composites (GFRRC) to be used in load-bearing areas of permanent teeth. Methods: Experimental materials were prepared using two different weight proportions, 7 wt% (1.75% E glass fibers) and 25 wt% (6.25% E glass fibers) of a GFRRC into an RMGIC matrix. Flexural strength was evaluated in 0- and 24-hour hydration periods, and fracture toughness was assessed after 24 hours. The internal microstructure of fractured samples was evaluated using a scanning electron microscope. Results: The addition of 25% of GFRRC was more effective in strengthening RMGIC than the introduction of only 7% GFRRC. Hydration periods did not show any significant statistical difference (P > 0.05). SEM micrographs of experimental materials' fractured surfaces revealed pull-out and fractured fibers; the presence of the matrix attached to fibers indicates great fiber-matrix adhesion. Within the limitations of the study, the results revealed that reinforcing RMGIC with discontinuous short E glass fiber flowable resin composites (GFRRC) improved significantly the flexural strength and modestly enhanced fracture toughness. [ABSTRACT FROM AUTHOR]

Copyright of Rudarsko-Geolosko-Naftni Zbornik is the property of Faculty of Mining, Geology & Petroleum Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The road performance decay law of EACRM under freeze-thaw cycles was studied using laboratory tests on the macroscopic scale in order to comprehensively analyze the serious performance damage mechanism of emulsified asphalt cold recycled mixture (EACRM) in cold regions during the service period. The surface cracking behavior, internal void evolution characteristics, and asphalt mortar morphology damage of EACRM under freeze-thaw cycles were studied by means of digital speckle, industrial CT, and scanning electron microscope (SEM) on the mesoscopic and microscopic scale. The results show that along with the increase in the number of freeze-thaw cycles, the road performance of EACRM decreases significantly. The surface of EACRM obviously cracks, and the width and number of main cracks increase significantly. The fatigue times of the maximum horizontal strain in the whole field gradually decrease. Air voids and the average volume of meso-void visibly increase. The microcracks of cement-emulsified asphalt mortar constantly emerge at the interface. The serious damage of the "three-dimensional network structure" is the fundamental reason for the performance decay of EACRM in cold regions. The performance damage of EACRM in cold regions is aggravated by water seeping into voids from cracks. Eventually, EACRM shows serious freeze-thaw inflicted damage. [ABSTRACT FROM AUTHOR]

Critical properties of metallic materials, such as the yield stress, corrosion resistance and ductility depend on the microstructure and its grain size and size distribution. Solute atoms that favorably segregate to grain boundaries produce a pinning atmosphere that exerts a drag pressure on the boundary motion, which strongly affects the grain growth behavior during annealing. In the current work, the characteristics of grain growth in an annealed Mg-1 wt.%Mn-1 wt.%Nd magnesium alloy were investigated by advanced experimental and modeling techniques. Systematic quasi in-situ orientation mappings with a scanning electron microscope were performed to track the evolution of local and global microstructural characteristics as a function of annealing time. Solute segregation at targeted grain boundaries was measured using three-dimensional atom probe tomography. Level-set computer simulations were carried with different setups of driving forces to explore their contribution to the microstructure development with and without solute drag. The results showed that the favorable growth advantage for some grains leading to a transient stage of abnormal grain growth is controlled by several drivers with varying importance at different stages of annealing. For longer annealing times, residual dislocation density gradients between large and smaller grains are no longer important, which leads to microstructure stability due to predominant solute drag. Local fluctuations in residual dislocation energy and solute concentration near grain boundaries cause different boundary segments to migrate at different rates, which affects the average growth rate of large grains and their evolved shape. [ABSTRACT FROM AUTHOR]

Few studies have focused on the influence of simulated toothbrush abrasion on the surface qualities of novel nanofilled and nanohybrid composites. The aim of the study was to evaluate the surface roughness and gloss values of resin-based composite (RBC) materials with various filler types before and after simulated toothbrush abrasion. One nanofilled (Filtek Z350 XT [FT3]), two nanohybrids (Harmonize [HM] and Clearfil Majesty [CM]) and one microhybrid (Filtek Z250 [FT2]) were evaluated. Twelve specimens of each material were made and polished with silicon carbide sandpapers. Initial surface roughness and gloss values were measured as negative controls. Then, all specimens were subjected to simulated toothbrush abrasion on a custom-made apparatus. After 2000, 4000 and 8000 cycles, the surface roughness and gloss values of all specimens were tested. One additional specimen from each group was selected for scanning electron microscope (SEM) analysis. For FT3, Ra and GU values did not significantly change until after 8000 cycles during the process of toothbrushing (P > 0.05). For HM, CM and FT2, the Ra and GU values significantly decreased after 4000 and 8000 cycles of toothbrush abrasion (P < 0.05). After 8000 cycles of toothbrush abrasion, FT3 presented the lowest surface roughness and highest gloss values of all materials (P < 0.05). SEM images showed that surface textures and irregularities corresponded to the results of surface roughness and gloss. Surface roughness and gloss after simulated toothbrush abrasion were material dependent. Nanofilled resin composite presented the lowest Ra values and highest GU values. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to evaluate and compare the remineralization potential of phosphorylated chitosan nanoparticles (Pchi) and silver diamine fluoride (SDF) compared to sodium fluoride varnish (NaF) on microhardness of artificial carious lesions in a biomimetic minimally invasive approach that is being regarded as the future of preventive dentistry. Methods: The sample size included 40 intact extracted maxillary anterior human teeth. Baseline microhardness was recorded using Vickers hardness test and energy-dispersive X-ray spectroscopy (EDX). Artificial caries-like lesions were created on the exposed enamel by suspending all teeth in demineralizing solution for 10 days in a temperature of 37 °C and then the hardness and EDX were remeasured. Samples were then divided into four main groups: Group A (positive control group) n = 10, treated with NaF, Group B n = 10, treated with SDF, Group C n = 10, treated with Pchi and Group D (negative control group) n = 10 that received no treatment. After treatment, samples were incubated in artificial saliva solution at 37 °C in for 10 days and then reassessed. Data were then recorded, tabulated, and statistically analyzed using Kruskal–Wallis test and Wilcoxon signed test. Scanning electron microscope (SEM) was used to analyze the morphological changes of enamel surface after treatment. Results: Groups B and C showed the highest calcium (Ca) and phosphate (P) content as well as hardness values, while group B had the highest percentage of fluoride. SEM revealed a smooth layer of mineral formed on the surface of enamel for both groups. Conclusion: Pchi and SDF showed the highest increase in enamel microhardness and remineralization potential. Clinical relevance: The minimally invasive approach for remineralization could be enhanced using SDF and Pchi. [ABSTRACT FROM AUTHOR]

Photocatalysis has recently been shown to be a good way to get rid of pollutants and produce hydrogen. MnFe 2 O 4 @g-C 3 N 4 was synthesized by solid state synthesis technique. In addition to producing hydrogen, MnFe 2 O 4 @g-C 3 N 4 demonstrated outstanding photocatalytic performance for the decay of pesticides under visible illumination. The morphology and structure of MnFe 2 O 4 @g-C 3 N 4 were approved using Scanning Electron Microscopes (SEM), X-ray diffraction (XRD). Morover, Fourier transform infrared spectroscopy (FT-IR), UV–vis DRS, and surface area (BET). Based on the degradation of the carbaryl contaminant, the photocatalytic action of MnFe 2 O 4 @g-C 3 N 4 was evaluated (94%). We for the first time could generate hydrogen by MnFe 2 O 4 @g-C 3 N 4 and develop its photocatalytic activities by expanding the surface area and narrowing the band gap value (1.7 eV) and a great surface area of 53.46 m2/g, as displayed by the outcomes. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This work investigates the formation, endurance and rupture of tribofilms on a honed engine liner subjected to boundary lubrication in a reciprocating Tribometer. Study focuses on the exploration of synergistic effect between ZDDP additive in the oil and two distinctly shaped nanoparticles, Graphene oxide (GO) and detonation nanodiamond (DND), in improving the characteristics of tribofilm. Tested samples were examined by scanning electron microscope and energy dispersive X-ray. The results indicated that the addition of nanoparticles to the base oil with ZDDP accelerates the tribofilm-formation. Although fully developed tribofilms were obtained with both the nanoadditives, the DND based tribofilm was more durable under the dry running conditions. However, P-rich tribofilm formed in the presence of GO showed self-mending characteristics. Nanoindentation studies on the wear tack revealed a 12% increase in elastic modulus and 23% increase in average hardness for the sample tested with DND compared to that of base lubricant. [ABSTRACT FROM AUTHOR]

The efficacy of sodium hypochlorite (NaOCl) as an intracanal irrigant is widely debated in endodontic therapy. This study aimed to analyze and compare the penetration abilities of different modes of NaOCl application and assess the impact of various agitation strategies on promoting root canal cleanliness. This study included 168 single-rooted mandibular premolars that were randomly divided into 8 groups. The 2 modes of application of 5% NaOCl evaluated were intracanal heating and preheating, and the agitation strategies included ultrasonic, sonic, and manual dynamic agitations. The samples were sectioned and observed at a magnification of 1000 × under a scanning electron microscope. The analysis of variance test showed a statistically significant difference among the various groups of agitation (P <.05). The post hoc Tukey test confirmed that preheated NaOCl with ultrasonic agitation, intracanal-heated NaOCl with sonic agitation, and manual dynamic agitation had significantly higher debris scores of 1, 4, and 5, respectively, in the apical third of the canal. The results indicated that the combination of intracanal-heated NaOCl and ultrasonic agitation is an effective method for reducing debris in the root canal system. These findings highlight the importance of considering both the mode of application and the agitation strategies when optimizing the use of NaOCl as an intracanal irrigant in endodontic therapy. [ABSTRACT FROM AUTHOR]

Epiphyses of ten hawkmoths species of Ambulycini (Lepidoptera: Sphingidae) are described using stereoscopic microscope and scanning electron microscopy. New terminologies are proposed for the structure. The epiphyses showed variations in the eight morphological characters and acanthae is described in a species. Sexual dimorphism is observed and discussed mainly in the size of the epiphyses, comb and acanthae. [ABSTRACT FROM AUTHOR]

The tribe Aphonoidini was established by Gorochov in 2008 and includes 18 genera. There are currently ten species of this tribe in China. Because female crickets of this tribe are relatively similar in external morphology and cannot be easily distinguished from one another, we have used the morphology of the ovipositor in this study with the objective of evaluate this value in the identification of the females. Here, we compare a total of five species of ovipositor in genera Aphonoides and Mistshenkoana of this tribe by Scanning Electron Microscope (SEM) and VHX–6000 digital microscope, of which Mistshenkoana kongtumensis Gorochov, 1990 was first introduced to China. By observing the apical morphology and sensilla of the ovipositor of these five species, we made a pictorial key to species of Aphonoidini from China based on the end of the ventral valvulae and obtained five kinds of sensilla, among which Aphonoides curvto and M. kongtumensis had one more SB (sensilla basiconica) than the other three species. This work confirms, to some extent, that the ovipositor can be used as a feature of species classification. [ABSTRACT FROM AUTHOR]

• Inorganic GSR from PPU ammunition cal. 7.65 mm were studied. • GSR patterns on cotton fabric in the range 25–125 cm are presented. • Distribution of GSR was established by SEM-EDX analysis. • Chemical and morphological GSR spread dependence on the shooting distance is demonstrated. • Empirical bases for forensic casework on shooting to assist casework were achieved. The subject of this research was the inorganic gunshot residue component collected from shooting patterns obtained on woven cotton cloth using a Pietro Beretta model 70 pistol, cal. 7.65 mm and Serbian ammunition for the following muzzle-to-target distances: 25, 50, 75, 100 and 125 cm. For each distance, three rounds of shooting were performed. Particles were lifted within a 10 cm radius of the projectile entrance and automatically analyzed using a scanning electron microscope coupled with an energy dispersion X-ray spectrometry. The obtained data on the populations of particles were analyzed taking into account their numbers, chemical classes and sizes. The results showed an apparent maximum incidence within all particles containing barium at about 50 cm distance. Also, lead particles revealed a distinct behaviour, being dominant at a 25 cm distance, falling below the other chemical classes, and finally becoming dominant again at 125 cm. The analysis of the frequency of occurrence of particles sorted according to their sizes confirmed that the small particle population is the largest, and their distribution in function of the equivalent circle diameter is exponential-like. The obtained results provided knowledge on the distribution of particles in the vicinity of the tested firearm and ammunition cal. 7.65 mm which generally corroborates with similarly studied GSR distributions obtained for the use of pistols cal. 9 mm. This information, together with the examinations of gunshot damages and other types of residues such as soot or unburned propellant grains may support qualitative inferences on shooting distance estimation, especially in cases, when the firearm and cartridges are not available to perform test shooting. In such cases even roughly estimated shooting distance can be helpful, e.g. for confirming or excluding the possibility of self-inflicted injuries or suicide and infer on the mutual position of the shooting stage actors. An example of casework that illustrates intermediate shooting distance estimation is presented. [ABSTRACT FROM AUTHOR]

A novel Mg-Al LDH film was in-situ prepared hydrothermally in an alkaline aqueous solution on an Al-alloyed AZ31 substrate. The structural, chemical and functional characteristics of the film were explored by means of scanning electron microscope (SEM), X-ray diffraction (XRD), energy dispersive spectrometer (EDS), polarization curve, AC impedance and salt immersion tests, respectively. The anti-corrosion results indicated that the Mg-Al LDH film on the Al-alloyed AZ31 surface could effectively protect the AZ31 from corrosion attack even after 90 days of immersion in 3.5 wt.% NaCl solution. The protection performance is surprisingly better than most of the reported coatings on Mg alloys. More interestingly, when the Mg-Al LDH film was scratched, the exposed Al-alloyed surface might gradually release metal ions and re-generate dense LDH nano-sheets in the corrosive environment to inhibit the further corrosion there, exhibiting a self-repairing behavior. The combination of the benign long-term protection and desirable self-repairing performance in this new process of surface-alloying and LDH-formation may significantly extend the practical application of magnesium alloys. [ABSTRACT FROM AUTHOR]

[Display omitted] The outer shell of the bulletproof fabric is one of the important parts that help the shield in performing its function of protection in the best way. In this paper, there are two types of high-performance materials used as the outer shell and finished with knife coating with fluorocarbon and polyurethane coating to improve the performance of the two materials. Five laboratory tests were conducted for both materials to show their functional performance efficiency, the ballistic test was applied using two types of calibers 7.62x54MSC and 7.62x54API. A scanning electron microscope was conducted to show the coating effect on samples. Paired sample T-tests were used to show the differences between variables. An improvement was shown in the performance for both ballistic nylon and Cordura after treatment. Finally cordura is more durable, as it recorded the highest value in Puncture test and less damaged, while ballistic nylon recorded the highest value in the abrasion resistance after the same treatment. [ABSTRACT FROM AUTHOR]

The fibers of the deep-sea sponge Euplectella aspergillum exhibit exceptional mechanical properties due to their unique layered structure at a micrometer length scale. In the present study, we utilize a correlative approach comprising of in situ tensile testing inside a scanning electron microscope (SEM) and post-failure fractography to precisely understand mechanisms through which layered architecture of fibers fracture and improves damage tolerance in tensile loading condition. The real-time observation of fibers in the present study confirms for the first time that the failure starts from the surface of fibers and proceeds to the center through successive layers. The concentric layers surrounding the central core sacrifice themselves and protect the central core through various toughening mechanisms like crack deflection, crack arrest, interface debonding, and fiber pullout. Biological materials often exhibit multiscale hierarchical structures that can be incorporated into the design of next generation of engineering materials. The fibers of deep-sea sponge E. aspergillum possess core-shell like layered architecture. Our in situ study reveals astounding strategies by which this architecture delays the fracture of the fiber. The core-shell architecture of these fibers behaves like fiber-reinforced ceramic matrix composite, where the outer shells act as a matrix and the central core acts as a fiber. The outer shells take the environmental brunt and scarify themselves to protect the central core. The precise understanding of damage evolution presented here will help to design architected materials for load-bearing applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of Science of Sintering is the property of National Library of Serbia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science of Sintering is the property of National Library of Serbia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the scope of the study, it was aimed to obtain antibacterial nanofiber surfaces containing Momordica oil, its ozonated oil form and its microcapsules forms. First of all, Mormodica oil was exposed to ozone gas for 135 min. After that, crude and ozonated mormodica oil were microencapsulated by using simple coacervation. Subsequently, %10 PLA polymer solution were prepared and used for obtaining PLA nanofiber surface by using solution blowing spinning. Besides, PLA polymer solution were mixed with crude mormodica oil, ozonated mormodica oil and their microcapsules forms and then these solutions were spun by using solution blowing spinning. Obtained ozonated oil, microcapsules and nanofiber surfaces were characterized via measurement of total unsaturated fatty acid amount in the oils, scanning electron microscope, FT-IR analysis and antibacterial activity test. The data showed that mormodica oil were ozonated. Microencapsulation process was done successfully and obtained nanofiber containing mormodica oil and its microcapsules. Moreover antibacterial activity showed that mormodica oil and ozonated mormodica oil showed antibacterial activity against to S.aureus and E.coli bacteria according to the disc diffusion method. The nanofiber surfaces containing ozonated oil and its microcapsules showed antibacterial activity against to S.aureus and E.coli bacteria according to the ASTM E 2149-01 method. As a result, it was obtained biodegradable nanofiber containing microcapsules and showing antibacterial activity. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to determine the effect of polishing press-on force on surface roughness and gloss of computer-aided designcomputer-aided manufacturing (CAD-CAM) composites. Methods: The materials evaluated included a CAD-CAM ceramic, a polymer-infiltrated ceramic, and three filler-based CAD-CAM composites. The CAD-CAM blocks were sectioned, embedded in self-cured resin, finished with abrasive papers and ultrasonically cleaned. Specimens were subsequently polished using the Sof-Lex disk system with 0.5, 1.0, 1.5, and 2.0 N press-on force by means of a custom-made apparatus. Contour arithmetic mean deviation (Ra) and gloss value (GU) data were acquired with a profilometer and glossmeter, respectively, and analyzed using ANOVA/ Bonferroni post hoc test and Pearson’s correlation (α = 0.05). Representative samples of the various materials at baseline and after each polishing step were examined under scanning electron microscope. Results: Mean Ra and GU values ranged from 0.096 ± 0.004 μmto 0.295 ± 0.045 μm and 13.4 ± 1.9 to 67.6 ± 11.3 correspondingly for the various material-force combinations. Surface roughness and gloss were found to be press-on force and material dependent. A moderately strong and negative correlation (rs = −0.69) existed between Ra and GU values. Conclusion: For optimal smoothness and gloss, ceramic and polymerinfiltrated ceramic CAD-CAM materials must be polished with a 2.0 N force, while filler-based CAD-CAM composites should, in general, be polished using a 1.0 to 1.5 N force. [ABSTRACT FROM AUTHOR]

A hierarchical superhydrophobic Al-Li layered double hydroxide (LDH) films with different Li+/Al3+ molar ratios of 1:1, 1:2, 2:1, pH value of 11.5 and reaction temperature of 125 °C, have been fabricated on the surface of Mg-5Li-1Al (LA51) alloys by hydrothermal method following the characteristics of controllable cation structure and exchangeable anion between layers. The properties of the films were investigated by X-ray diffractometer (XRD), scanning electron microscope (SEM) and energy dispersive spectrometer (EDS). XRD and SEM results indicate that the Al-Li LDH films are successfully prepared on LA51 alloys. The contact angle (CA) was measured to be about 100.7°, indicating that the surface wettability of the film converted from hydrophilic to hydrophobic by surface modification. The corrosion resistance of Al-Li LDH films was evaluated by Tafel polarization curve and electrochemical impedance spectroscopy (EIS). Surprisingly, Tafel polarization curve and EIS test reveal that the Al-Li LDH films prepared at the molar ratio of Li+/Al3+ 1:2, pH 11.5 and temperature 125 °C have better corrosion resistance in 0.1 M NaCl neutral solution. In addition, the formation mechanism and corrosion mechanism of the films on the surface of LA51 alloy are also proposed. It provides innovative synthetic materials and novel design ideas for the preparation of high-efficiency anti-corrosion coatings on LA51 alloys, whose application can be extended in industrial fields. [ABSTRACT FROM AUTHOR]

This study investigated the effectiveness of palm kernel leaves extract (PKLE) as green inhibitor using Central Composite Design (CCD). Phytochemical analysis was performed on the extract. Process variables used for the optimization in this study were: concentration of extract (0.5–1.5 g per litre), time (3–5 days), and temperature (30–50 °C) respectively. Surface characterization was done with Scanning Electron Microscope (SEM). Bioactive constituents were observed from the result of the phytochemical analysis. The best process levels were: inhibitor concentration (1.500 g/l), temperature (30 °C) and time (3 days) with inhibition efficiency of 96.74 %; while the optimal process level validated gave 97.20 %. The SEM results revealed that more film was observed on the validated optimal process level. The PKLE extract was an effective inhibitor. [ABSTRACT FROM AUTHOR]