scholarly journals Impact of heating conditions on the synthesis dynamics of composites in a cylindrical mold

2019 ◽  
Vol 681 ◽  
pp. 012005
Author(s):  
N V Bukrina ◽  
A G Knyazeva
Keyword(s):  
Cylindrical Mold

Influence of Gravity and Mold Shape on Molding of Aluminum Foams

2014 ◽  
Vol 875-877 ◽  
pp. 1280-1284
Author(s):  
Masanori Shiomi ◽  
Tomohiro Fukaya
Keyword(s):  
Melting Point ◽  
Aluminum Foam ◽  
Large Diameter ◽  
Mold Filling ◽  
Light Weight ◽  
Aluminum Foams ◽  
Forming Process ◽  
Molding Process ◽  
Foaming Agent ◽  
Cylindrical Mold

A molding process of aluminum foams by using a rotating mold is proposed in order to improve the mold filling and forming process for light-weight parts of vehicles. Aluminum powder mixed with a foaming agent is extruded into the mold through the die heated to a temperature higher than the melting point, and the mold is filled with the aluminum foam. When the diameter of a cylindrical mold is large, the influence of gravity is significant and the mold is not filled successfully. In the proposed molding, the aluminum foam is extruded into the rotating mold of large diameter and the volumetric ratio of foam to mold cavity is improved. However, the effect of the mold rotation on the mold filling is limited due to friction.

The effect of the temperature dependence of the heat conductivity on the physical laws of the bulk synthesis of a composite

2021 ◽  
pp. 33-39
Author(s):  
N.V. Bukrina ◽  
Keyword(s):  
Temperature Dependence ◽  
Heat Conductivity ◽  
Chemical Compounds ◽  
Heat Conductivity Coefficient ◽  
Temperature Dependent ◽  
High Temperature Synthesis ◽  
Formal Kinetic ◽  
Cylindrical Mold ◽  
Comparison Of The Results ◽  
Physical Laws

Two-dimensional model of high-temperature synthesis of chemical compounds and alloys in a dynamic thermal explosion mode when a powder compact is heated in a steel cylindrical mold by an induction heat source are proposed. The complex of chemical reactions is described by a total reaction with effective formal kinetic parameters. The kinetic law takes into account strong retardation of the reaction by the layer of the synthesized product that prevents the interaction of the reagents. The model makes it possible to investigate the macroscopic physical laws of the synthesis of a composite with a change in the heating rate and reactor dimensions. It is made a comparison of the results obtained for a constant heat conductivity coefficient and a temperature-dependent heat conductivity coefficient. It is revealed that taking into account the temperature dependence of the heat conductivity coefficient can lead to a numerical change in the ignition delay time and to a qualitatively different temperature distribution in the reactor bulk.

Axisymmetric solidification in a long cylindrical mold

1985 ◽  
Vol 42 (3) ◽  
pp. 229-244 ◽  
Author(s):  
S. C. Gupta
Keyword(s):  
Cylindrical Mold

Continuous Casting of Particulate Silica Gels

1989 ◽  
Vol 172 ◽  
Author(s):  
E. M. Rabinovich ◽  
K. A. Jackson ◽  
Nonna A. Kopylov
Keyword(s):  
Continuous Casting ◽  
Temperature Dependence ◽  
Feasibility Study ◽  
Sol Gel ◽  
Activation Energies ◽  
Silica Gels ◽  
Gelling Agent ◽  
Cylindrical Mold ◽  
Silica Sols ◽  
Particulate Silica

AbstractA feasibility study of continuous casting of particulate silica sols has been conducted. The process consists in measured pumping of the sol and a gelling agent into a heated mold where the sol gels. The gel is continuously pushed out of the cylindrical mold by the pressure of the pumped sol. Gel rods of 2.5 cm diameter, up to 150 cm long, were prepared by this method. Temperature dependence of the gelation was studied, and activation energies of the process were determined.

Elution Study of Three Light-Cured Orthodontic Adhesives

2019 ◽  
Vol 294 ◽  
pp. 59-64
Author(s):  
Pitchaya Roongrujimek ◽  
Niwat Anuwongnukroh ◽  
Surachai Dechkunakorn
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Immersion Medium ◽  
Orthodontic Adhesives ◽  
Cylindrical Mold

Objectives: The aim of the study was to evaluate monomer elution from three commercial orthodontic adhesive pastes. Methods: Three monomers BPA, Bis-GMA, and TEGDMA were observed from Green Glue (Hangzhou Westlake Biomaterials Co., Zhejiang, China), GrenGloo (Ormco Co., Glendora, CA, USA), and Transbond XT (3M Unitek, St. Paul, MN, USA). The adhesive was light-cured in a cylindrical mold with 6 mm in diameter and 2 mm thick, before immediately immerse into 10 ml extraction media of 75%ethanol in a tightly sealed container at 37°C. The solution was refreshed at four intervals of time 1, 3, 5, and 7 d. The immersion medium was determined using High-performance liquid chromatography (HPLC). Results and Conclusions: BPA were found from three adhesives. Bis-GMA was found only from Transbond XT. TEGDMA were found from both Green Glue and Grengloo. Green Glue had 10-30 times higher TEGDMA elution than Grengloo. Major elution was found from all orthodontic adhesive paste within 1 d, and decrease with time to 7 d.

A novel tight cylindrical mold for epoxy resin embedding allows enhanced microscopic analysis of microcores extracted from woody plants

2021 ◽  
pp. 125875
Author(s):  
Yuichiro Oribe ◽  
Michira Morioka ◽  
Chihiro Shirahama ◽  
Shinya Kawabe ◽  
Eri Nabeshima ◽  
...  
Keyword(s):  
Epoxy Resin ◽  
Woody Plants ◽  
Microscopic Analysis ◽  
Cylindrical Mold

scholarly journals Surface Geometry of Four Conventional Nanohybrid Resin-Based Composites and Four Regular Viscosity Bulk Fill Resin-Based Composites after Two-Step Polishing Procedure

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Mateusz Granat ◽  
Janusz Cieloszyk ◽  
Urszula Kowalska ◽  
Jadwiga Buczkowska-Radlińska ◽  
Ryta Łagocka
Keyword(s):  
Surface Roughness ◽  
Surface Structure ◽  
Smooth Surface ◽  
Nonparametric Tests ◽  
Matched Pair ◽  
Surface Geometry ◽  
Sem Images ◽  
Posterior Teeth ◽  
Cylindrical Mold ◽  
Slight Damage

Objectives. The aim of the study was to determine the quantitative and qualitative surface structure of contemporary RBCs in posterior teeth reconstructions: regular viscosity bulk fill and conventional composites, obtained after two-stage polishing procedure. Materials and Methods. Four conventional nanohybrid composites (Tetric EvoCeram, GrandioSO, Filtek Z550, and Ceram·X Mono) and four regular viscosity bulk fill composites (Tetric EvoCeram Bulk Fill, X-tra fil, Filtek Bulk Fill Posterior, and QuixFil) were tested. Samples of each RBC were prepared using PMMA cylindrical mold. After two-step polishing procedure, a surface geometry was evaluated under profilometry (Turbowave v. 7.36, Hommel-Etamic) and SEM (VEGA 3, Tescan Analytics). To evaluate differences between values, the following nonparametric tests were used: Friedman’s ANOVA, Wilcoxon’s matched-pair test, ANOVA Kruskal-Wallis, and Mann-Whitney U. Results. All conventional RBCs showed Ra values in the range of 0.20-0.26 μm. Bulk fill showed higher values in range of 0.49-1.36 μm except for Filtek Bulk Fill Posterior, which achieved 0.23 μm Ra value. SEM images of conventional RBCs were described as smooth surfaces with slight damage except for TEC, which presented smooth surface with no damage. Bulk fill composites showed rough surface, except for TBF, which presented smooth surface with slight damage. Conclusions. Regular viscosity bulk fill composites do not constitute a homogeneous group regarding surface roughness after polishing. They obtain, for the most part, poorer smoothness values after polishing than conventional RBCs.

Bone with a Vascular Flap Induced from Fat Tissue with the Use of rhBMP-2 in Rats

2003 ◽  
Vol 82 (8) ◽  
pp. 581-584 ◽  
Author(s):  
M. Hosoya ◽  
Y. Maruoka ◽  
M. Oda ◽  
I. Asahina ◽  
S. Ichinose ◽  
...  
Keyword(s):  
Bone Formation ◽  
Blood Vessels ◽  
Bone Morphogenetic Protein 2 ◽  
Control Group ◽  
Fat Tissue ◽  
Morphogenetic Protein ◽  
Human Bone Morphogenetic Protein ◽  
Cylindrical Mold ◽  
Recombinant Human Bone

Here we report that successful bone formation with a vascular flap inside a cylindrical mold was induced from fat tissue with the use of recombinant human bone morphogenetic protein-2 in rats. Fat tissue connected to blood vessels was prepared to fit into the mold and implanted intramuscularly into the hind leg in Wistar rats. RhBMP-2 (20 μg) was applied in a collagen sheet previously placed on the inside surface of the mold. Bone formation was confirmed radiologically and morphologically at 2, 4, and 8 weeks after the surgery. In the control group without rhBMP-2 or the group with ligation of the blood vessels before the implantation, bone formation was not observed. Our success in bone formation having a definite size, shape, and blood supply may lead to a therapeutic approach to effective bone reconstitution. The present study is the first report on bone induction from fat tissue by rhBMP-2 in vivo.

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