volume porosity
Recently Published Documents


TOTAL DOCUMENTS

87
(FIVE YEARS 46)

H-INDEX

7
(FIVE YEARS 3)

Author(s):  
V. V. Liubych ◽  
◽  
V. V. Zheliezna ◽  
D. M. Hrabova

Aims. To study the quality formation of a cupcake made from triticale flour enriched with pumpkin paste. Methods. Laboratory, mathematical and statistical, physicochemical. Results. The article presents the study results of the quality formation of triticale cupcakes (baking, shrinkage, moisute, volume, porosity), enriched with pumpkin paste. It is established that the quality of triticale cupcakes varies significantly from the pumpkin paste content. As a result of research, it was found that the baking rate of cupcakes varied depending on the pumpkin paste content and was 2.77–3.90 %. This indicator is the lowest in the control variant - without pumpkin paste addition – 2.77 %. Variants with the addition of 5, 15, 35 and 40% of pumpkin paste were characterized by high rates, where the baking rate was 3.72, 3.8, 3.85 and 3.9, respectively. In other experiment variants it was at the level of 3.14–3.63 %. Shrinkage of triticale flour cupcakes enriched with pumpkin paste did not change significantly and amounted to 1.0–1.4 %. It was found that with pumpkin paste addition, the moisture of the cupcakes increased from 21.4 with 5% of pumpkin paste to 36.1 % with 50 %. The highest moisture was characterized by variants with a content of 40, 45 and 50 % of pumpkin paste, respectively, 33.4, 33.2 and 36.1 %. When pumpkin paste is added to the dough, cupcake volume increases from 5 to 50 %. It is obvious that the absence of pumpkin gluten in the paste is the main reason for intensity decrease in the processes of dough leavening and increasing its density. Therefore, with pumpkin paste addition, the porosity of baked goods was not developed, the pores are small and thick-walled. Thus, cupcake porosity was 28.4–55.6 %. This figure was the highest with the addition of 5 % of pumpkin paste – 55.6 %, which is 5.4 % more than control. As the amount of pumpkin paste increased, the cupcake porosity also decreased. Conclusions. In the technology of triticale cupcakes, it is optimal to add 25–30 % of pumpkin paste by dough weight.


2021 ◽  
pp. 108201322110639
Author(s):  
Sara Naji-Tabasi ◽  
Mostafa Shahidi-Noghabi ◽  
Maryam Davtalab

The purpose of this study was to use a mixture of whole wheat–barley flour mixture in the preparation of traditional Iranian bread (Barbari) in the optimum condition of fermentation to benefit from all available nutrients. In this study, bread parameters such as specific volume, porosity, textural characteristics, zinc, iron, phytic acid and organoleptic properties were investigated. In this research, different percentages of sourdough (15–30%) and fermentation time (30 – 120 min) were applied. Results showed that the phytic acid content significantly decreased ( p < 0.05) (0.23 – 0.14) by increasing sourdough and fermentation time, which result in increasing in zinc (17.49 – 22.89%) and iron (36.44 – 45.32%) content. Both the sourdough content and fermentation time parameters had a significant effect ( p < 0.05) on the better porosity (9.05 – 13.50%) and overall acceptability of bread (2.15 – 3.85). The hardness, gumminess, chewiness, porosity, phytic acid and overall acceptance parameters were used to optimize the fermentation conditions of Barbari bread by response surface methodology using a central composite design. Optimal conditions for the production of Barbari bread were 29.53% sourdough and 120 min fermentation time. Under optimal conditions, the overall acceptance, hardness, porosity, chewability, gumminess and phytic acid were 3.84, 60.81 N, 14.09%, 302.01 N/mm, 41.37 N and 0.15%, respectively.


2021 ◽  
Vol 11 (6) ◽  
pp. 7841-7845
Author(s):  
S. Tomescu ◽  
I. O. Bucur

In this research paper, a numerical study regarding gas-oil separation is presented. Employing the geometry of a classic separator used by the NRDI for Gas Turbines COMOTI and a Computer-Aided Design (CAD) software, the computational domain was defined. To perform the Computational Fluid Dynamics (CFD) investigation, the mesh was created with the ANSYS Meshing tool, and the ANSYS CFX was employed as a solver. The computational domain was split into 5 subdomains, 3 were fluid and 2 were defined as porous media. The volume porosity, loss model, and permeability were set up. In terms of turbulence flow, the standard k–ε model was adopted. The results of the numerical calculations in terms of oil volume fraction and streamline profiles were used to analyze the separator configuration. The results show that the numerical investigation with the VOF (Volume of Fluid Method) - CFD model is capable of analyzing the performance of a two-phase separator equipped with two demisters-porous media.


2021 ◽  
Vol 21 (4) ◽  
pp. 99-111
Author(s):  
Monika Górnik ◽  
Ewa Jonda ◽  
Monika Nowakowska ◽  
Leszek Łatka

Abstract The paper presents the computational studies on the microstructure of WC-Co-Cr coatings deposited by High Velocity Oxy Fuel spraying (HVOF). The study covers the porosity assessment according to ASTM E2109-01 standard, carried out in ImageJ software, in terms of volume porosity, size and shape of the pores. The evaluation was preceded by scanning electron microscope (SEM) observations at magnifications of 2000x and 5000x. Additionally, topography analysis has been performed by confocal laser scanning microscope (CLSM), and the surface roughness Ra was evaluated by the contact method with use of a stylus profilometer. Finally, the influence of porosity was observed for coatings microhardness HV0.3. According to the results, the total closed porosity was found to be in the range of 5.01 vol.% and 5.38 vol.%. The dominated pores in the coatings were of size 0.1-1.0 μm. Studies showed that HVOF process enabled deposition of dense coatings, characterized by homogenous distribution of pores and low roughness.


2021 ◽  
Vol 2131 (5) ◽  
pp. 052043
Author(s):  
Yu Bagaiskov

Abstract Quality assurance and processing capacity are essential performance parameters of abrasive tools. It is of prime importance for grinding wheels operating at a speed of 35–60 m/s. In this case, the opportunities to increase the high-rate grinding efficiency without burns are associated with using high-porosity and low-hardness wheels. Artificial pore-forming agents are used to manufacture tools. Introduction of pore-forming agents decreases grinding forces and increases the maximum grinding depth without burns. The porosity of filled compound materials can be attributed to the conception of gas permeability. The gas permeability parameter describes the openness degree of such structures and the velocity of the air volumes passing through porous materials. The porosity and gas-permeability degrees of the material of high-porous ceramic-bond abrasive tools with various parameters, depending on the abrasive material type, porogen grain size and content, and the composite structure number have been studied. It appeared that the porosity degree of high-porous abrasive tools, made both of fused alumina and silicon carbide increases as the structure number, grain size, and content of burning porogens increases. Besides, the increase degree of fused alumina is a little higher than that of silicon carbide. The gas permeability degree depends on the factors mentioned above in nearly the same way. Compared to porosity, the effect of gas permeability increases due to an altered structure, grain size, and content of porogens is much higher, up to 6 times. In this case, the gas permeability value is primarily characteristic of the pore size; in other words, the speed and volume of the air or lubrication and cooling fluid penetrating the material structure increase correspondingly at nearly the same increase of the pore size by several times and at the same volume porosity degree. The gas permeability degree can be used for quantitative and qualitative description of the material structure of high-porous abrasive tools, as well as their structural and mechanical parameters. The operating parameters of tools can depend on the gas permeability level of their materials. Thus, the results of abrasive processing can be foreseen.


2021 ◽  
Vol 25 (3) ◽  
pp. 275-284
Author(s):  
Helmer Fernando Alarcón Olave ◽  
Edwar Hernando Herrera Otero

The Cesar-Ranchería basin has all the necessary elements for the generation, expulsion, and migration of hydrocarbons and considerable potential for coal bed methane (CBM) in Colombia. Previous studies in the Cesar basin focused on understanding the tectonic evolution, stratigraphy, hydrocarbon generation potential, and evaluation of reservoir potential in Cretaceous calcareous units and quartzose sandstones from the Paleocene Barco Formation. These studies had confirmed the existence of an effective petroleum system, with several episodes of oil expulsion and re-emigration in the Miocene period, turning the Cenozoic clastic succession (Barco, Los Cuervos, La Loma, and Cuesta formations) into an element of significant exploratory interest to clarify the potentiality of the basin in terms of hydrocarbon accumulation. The petrophysical parameters of Cenozoic units (shale volume, porosity, water, and oil saturation) were determined by integrating wells log and core samples analyses from three stratigraphic wells. The integration of these results synthesizes the petrophysical behavior of the units. It defines intervals with clay volumes of less than 30%, effective porosity around 20%, which means favorable characteristics as reservoir rocks that need to be considered in future exploratory projects.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1704
Author(s):  
Liubov Safonova ◽  
Maria Bobrova ◽  
Anton Efimov ◽  
Lyubov Davydova ◽  
Timur Tenchurin ◽  
...  

The main goal of our research was to fabricate electrospun scaffolds from three different silk proteins—silk fibroin from Bombyx mori silkworm cocoons and two recombinant spidroins, rS2/12 and rS2/12-RGDS—and to perform a comparative analysis of the structure, biological properties, and regenerative potential of the scaffolds in a full-thickness rat skin wound model. The surface and internal structures were investigated using scanning electron microscopy and scanning probe nanotomography. The structures of the scaffolds were similar. The average fiber diameter of the scaffolds was 315 ± 26 nm, the volume porosity was 94.5 ± 1.4%, the surface-to-volume ratio of the scaffolds was 25.4 ± 4.2 um−1 and the fiber surface roughness was 3.8 ± 0.6 nm. The scaffolds were characterized by a non-cytotoxicity effect and a high level of cytocompatibility with cells. The scaffolds also had high regenerative potential—the healing of the skin wound was accelerated by 19 days compared with the control. A histological analysis did not reveal any fragments of the experimental constructions or areas of inflammation. Thus, novel data on the structure and biological properties of the silk fibroin/spidroin electrospun scaffolds were obtained.


Agronomy ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1977
Author(s):  
Georgiana Gabriela Codină ◽  
Cristina Sarion ◽  
Adriana Dabija

The aim of this study was to investigate the possibility of reducing the acrylamide content of bread samples obtained from wheat flour with a high extraction rate by adding a dry sourdough (SD) into the bread recipe. According to the data obtained, compared to the control sample the acrylamide content was significantly reduced (p < 0.05) by more than 50% for the bread samples in which low levels of SD of 1–3% were added to wheat flour. More so, due to the fact that SD affects bread quality, its technological effects on bread making have been investigated. The dough’s rheological properties (mixing and pasting using Mixolab, extension using Alveograph, fermentation using Rheofermentometer), falling number value, and bread quality parameters (loaf volume, porosity, elasticity, color, textural and sensory qualities) have been investigated. In general, SD addition caused a weakening effect on wheat flour dough, an increase in the total volume of CO2 produced during fermentation and a decrease in the falling number value. On bread quality, SD addition improved bread physical characteristics, darkened the bread crumb and crust, decreased the textural parameters (firmness, gumminess, cohesiveness and resilience) and improved the bread sensory characteristics for the samples with the addition of 1–2% SDto wheat flour.


2021 ◽  
Author(s):  
E. P. Putra

The Globigerina Limestone (GL) is the main reservoir of the seven gas fields that will be developed in the Madura Strait Block. The GL is a heterogeneous and unique clastic carbonate. However, the understanding of reservoir rock type of this reservoir are quite limited. Rock type definition in heterogeneous GL is very important aspect for reservoir modeling and will influences field development strategy. Rock type analysis in this study is using integration of core data, wireline logs and formation test data. Rock type determination applies porosity and permeability relationship approach from core data, which related to pore size distribution, lithofacies, and diagenesis. The analysis resulted eight rock types in the Globigerina Limestone reservoir. Result suggests that rock type definition is strongly influenced by lithofacies, which is dominated by packstone and wackestone - packstone. The diagenetic process in the deep burial environment causes decreasing of reservoir quality. Then the diagenesis process turns to be shallower in marine phreatic zone and causes dissolution which increasing the reservoir quality. Moreover, the analysis of rock type properties consist of clay volume, porosity, permeability, and water saturation. The good quality of a rock type will have the higher the porosity and permeability. The dominant rock type in this study area is RT4, which is identical to packstone lithofasies that has 0.40 v/v porosity and 5.2 mD as average permeability. The packstone litofacies could be found in RT 5, 6, 7, even 8 due to the increased of secondary porosity. It could also be found at a lower RT which is caused by intensive cementation.


2021 ◽  
Vol 1 (2) ◽  
pp. 55-70
Author(s):  
Hendra Himawan ◽  
◽  
Indra Sumantri ◽  
Okky Yuditya Pahlevi

The Madura Strait PSC is located in the southern part of North East Java Basin with biogenic gas from Globigerina limestone Pliocene Mundu and Selorejo sequence as main target. At early stage of field development,understanding and knowledge about petrophysical and elastic properties of reservoir rock quality is required and very important. The petrophysical analysis provide properties such as clay volume, porosity, permeability, water saturation and mineral volume to separate reservoir and non-reservoir zone. The elastic rock properties such as acoustic impedance (AI), shear impedance (SI), velocity ratio (Vp/Vs), and Poisson’s ratio (σ) were generated to identify clay zone, gas and non-gas also focused to distinguish reservoir rock quality inside gas zone as an effective reservoir characterization. This research is done by utilize core data, quad combo logs from eleven wells and shear velocity from eight wells. The purpose of this research is to optimize development well target in Globigerina limestone gas reservoir, which have good to best reservoir rock quality shown with high porosity and permeability,low clay volume and water saturation. Results from this research indicate that lime mud matrix have significant impact in the reservoir rock quality. Meanwhile, gas saturation can affect the elastic properties due to this high gas saturation can decrease compressional velocity (Vp) value. Finally, the integration of petrophysical result and combination of elastic properties implementation can help in distinguishing the best reservoir rock quality, which contains gas that should be penetrated by the development wells


Sign in / Sign up

Export Citation Format

Share Document