Overview of foam system: Natural material-based foam, stabilization, characterization, and applications

2022 ◽  
Vol 125 ◽  
pp. 107435
Author(s):  
Fuchao Zhan ◽  
Mahmoud Youssef ◽  
Bakht Ramin Shah ◽  
Jing Li ◽  
Bin Li
Keyword(s):  
Natural Material ◽  
Foam Stabilization

Implementasi Analisis Proses Bisnis Sebagai Upaya Pengurangan Biaya

2019 ◽  
Vol 10 (1) ◽  
pp. 1-27
Author(s):  
Aniek Wijayanti
Keyword(s):  
Business Process ◽  
Cost Reduction ◽  
Process Analysis ◽  
Value Added ◽  
Added Value ◽  
Natural Material ◽  
Management Activity ◽  
Procurement Process ◽  
Material Procurement ◽  
The Cost

Business Process Analysis can be used to eliminate or reduce a waste cost caused by non value added activities that exist in a process. This research aims at evaluating activities carried out in the natural material procurement process in the PT XYZ, calculating the effectiveness of the process cycle, finding a way to improve the process management, and calculating the cost reduction that can achieved by activity management. A case study was the approach of this research. The researcher obtained research data throughout deep interviews with the staff who directly involved in the process, observation, and documentation of natural material procurement. The result of this study show that the effectiveness of the process cycle of natural material procurement in the factory reached as much as 87,1% for the sand material and 72% for the crushed stone. This indicates that the process still carry activities with no added value and still contain ineffective costs. Through the Business Process Mechanism, these non value added activities can be managed so that the process cycle becomes more efficient and cost effectiveness is achieved. The result of the effective cycle calculation after the management activities implementation is 100%. This means that the cost of natural material procurement process has become effective. The result of calculation of the estimated cost reduction as a result of management activity is as much as Rp249.026.635,90 per year.

The Status of Mind and Intellect in Digital Environment

2020 ◽  
Vol 63 (2) ◽  
pp. 123-143
Author(s):  
Elena I. Yaroslavtseva
Keyword(s):  
Human Life ◽  
Cognitive Activity ◽  
Memory Loss ◽  
Natural Material ◽  
Human Being ◽  
Connection To Nature ◽  
Digital World ◽  
The Status ◽  
Natural Foundation ◽  
The Impact

The article examines the impact of digitalization on human life and intellectual experience. The development of computer technology demands an understanding of new aspects of human development and requires a capability to overcome not only external conditions but also ourselves. Entering a new level of development cannot imply a complete rejection of previous dispositions, but should be accompanied by reflection on personal experience and by the quest for new forms of interaction in society and with nature. Communicative and cognitive activity of a person has an ontological basis and relies on processes that actually evolve in nature. Therefore, the creation of new objects is always associated with the properties of natural material and gives rise to new points of support in the development of man. The more audacious his projects, the more important it is to preserve this connection to nature. It is always the human being who turns out to be the initiator who knows how to solve problems. The conformity of complex technical systems to nature is not only a goal but also a value of meaningful construction of development perspectives. The key to the nature orientation of the modern digital world is the human being himself, who keeps all the secrets of the culture of his natural development. Therefore, the proposed by the Russian philosopher V.S. Stepin post-non-classical approach, based on the principle of “human-sizedness,” is an important contribution to contemporary research because it draws attention to the “human – machine” communication, to the relationship between a person and technological systems he created. The article concludes that during digital transformation, a cultural conflict arises: in an effort to solve the problems of the future, a person equips his life with devices that are designed to support him, to expand his functionality, but at the same time, the boundaries of humanity become dissolved and the forms of human activity undergo simplification. Transhumanism engages society in the fight against fears of vulnerability and memory loss and ignores the flexibility and sustainability of natural foundation.

scholarly journals On the Thermal Stresses Due to Weathering in Natural Stones

2021 ◽  
Vol 11 (3) ◽  
pp. 1188
Author(s):  
William Hideki Ito ◽  
Talita Scussiato ◽  
Federico Vagnon ◽  
Anna Maria Ferrero ◽  
Maria Rita Migliazza ◽  
...  
Keyword(s):  
Building Materials ◽  
Thermal Stresses ◽  
Central Italy ◽  
Theory Of Elasticity ◽  
International Standards ◽  
Natural Material ◽  
Physical Weathering ◽  
Mechanism Of Degradation ◽  
Ancient Times ◽  
Natural Stones

Natural weathering is known as one of the key mechanisms causing degradation in building materials. Great efforts have been made to develop new materials and new processes for protecting those that already exist. Natural stones are an example of a natural material that has been extensively used for building construction since ancient times. In addition, they fit durability, aesthetic, and mechanical requirements. Thus, they still have great importance in the construction business nowadays. Though chemical interactions in natural stones, such as oxidation or hydrolyses, have been widely studied, in the last few decades, the physical weathering due to daily temperature variations has begun to be considered as a key mechanism of degradation and has been incorporated in international standards. This process is particularly important in calcitic marble slabs, where it can cause extensive damages to facades. Consequently, there are restrictive rules for the use of marble as an external coating material in many countries. In this paper, the thermal stresses induced by daily variations in temperature are calculated using geographic and meteorological information. The concept of sol-air temperature is used to estimate the temperatures of the hidden and exposed surfaces of a slab, and Fourier’s law and the theory of elasticity are used to calculate the temperature and stress distribution, respectively. The proposed methodology allows for a detailed reconstruction of the stress induced inside marble slabs using parameters commonly acquired in meteorological stations as input data. The developed methodology was validated by comparing in-situ measurements of the temperature of a building in Pescara (Central Italy). A good correlation between the theoretical and real temperatures was found; in particular, the peak tensile stresses inside the slabs were estimated at 75 kPa.

scholarly journals Impact of tailored water chemistry aqueous ions on foam stability enhancement

2021 ◽  
Author(s):  
Zuhair AlYousef ◽  
Subhash Ayirala ◽  
Majed Almubarak ◽  
Dongkyu Cha
Keyword(s):  
Aqueous Solutions ◽  
Water Chemistry ◽  
Foam Stability ◽  
Chloride Salt ◽  
Foam Generation ◽  
Monovalent Ions ◽  
Injection Water ◽  
Foam Stabilization ◽  
Aqueous Ions ◽  
The Impact

AbstractGenerating strong and stable foam is necessary to achieve in-depth conformance control in the reservoir. Besides other parameters, the chemistry of injection water can significantly impact foam generation and stabilization. The tailored water chemistry was found to have good potential to improve foam stability. The objective of this study is to extensively evaluate the effect of different aqueous ions in the selected tailored water chemistry formulations on foam stabilization. Bulk and dynamic foam experiments were used to evaluate the impact of different tailored water chemistry aqueous ions on foam generation and stabilization. For bulk foam tests, the stability of foams generated using three surfactants and different aqueous ions was analyzed using bottle tests. For dynamic foam experiments, the tests were conducted using a microfluidic device. The results clearly demonstrated that the ionic content of aqueous solutions can significantly affect foam stabilization. The results revealed that the foam stabilization in bulk is different than that in porous media. Depending on the surfactant type, the divalent ions were found to have stronger influence on foam stabilization when compared to monovalent ions. The bulk foam results pointed out that the aqueous solutions containing calcium chloride salt (CaCl2) showed longer foam life with the anionic surfactant and very weak foam with the nonionic surfactant. The solutions with magnesium chloride (MgCl2) and CaCl2 salts displayed higher impact on foam stability in comparison with sodium chloride (NaCl) with the amphoteric alkyl amine surfactant. Less stable foams were generated with aqueous solutions comprising of both magnesium and calcium ions. In the microfluidic model, the solutions containing MgCl2 showed higher resistance to gas flow and subsequently higher mobility reduction factor for the injection gas when compared to those produced using NaCl and CaCl2 salts. This experimental study focusing about the role of different aqueous ions in the injection water on foam could help in better understanding the foam stabilization process. The new knowledge gained can also enable the selection and optimization of the right injection water chemistry and suitable chemicals for foam field applications.

Experimental Investigation of Microcutting Mechanisms in Marble Grinding

2009 ◽  
Vol 131 (6) ◽  
Author(s):  
LJ. Tanovic ◽  
P. Bojanic ◽  
R. Puzovic ◽  
S. Klimenko
Keyword(s):  
Experimental Study ◽  
Experimental Investigation ◽  
Cutting Force ◽  
Surface Finish ◽  
Normal Component ◽  
Natural Material ◽  
Grinding Process ◽  
Force Component ◽  
Diamond Grain

This paper offers an experimental study of the microcutting mechanisms in marble grinding to aid the optimization of the marble grinding process. The necessity for investigating these mechanisms is dictated by the increased use of marble in many applications and the fact that grinding and polishing processes are the dominant technologies used to meet surface finish requirements in this natural material. The experiments are aimed at the determination of the normal component of the cutting force and of the grain traces in microcutting with a single diamond grain. The investigations carried out make provisions for establishing critical grain penetration and cutting depths and allow the prediction of the normal cutting force component as a function of grain penetration speed and depth.

Gradient of Soil Constitutive Model

2010 ◽  
Vol 168-170 ◽  
pp. 1126-1129
Author(s):  
Wen Xu Ma ◽  
Ying Guang Fang
Keyword(s):  
Plastic Strain ◽  
Strain Gradient ◽  
Soil Analysis ◽  
Natural Material ◽  
Flow Rule ◽  
The Finite Element Method ◽  
Gradient Effect ◽  
Non Local ◽  
Associated Flow Rule ◽  
Plastic Strain Gradient

For the soil is a very complex natural material, significant strain gradient effect exist in soil analysis. Based on the "gradient" phenomenon, we add the plastic strain gradient hardening item into the traditional Cambridge yield surface. By using the consistency conditions and associated flow rule, we get the explicit expression of plastic strain gradient stiffness matrix. And the finite element method of plastic strain gradient is also shown in this article. Plastic strain gradient is actually a phenomenological non-local model containing microstructure information of the material. It may overcome the difficulties in simulating the gradient phenomenon by traditional mechanical model.

scholarly journals Hierarchical spidroin micellar nanoparticles as the fundamental precursors of spider silks

2018 ◽  
Vol 115 (45) ◽  
pp. 11507-11512 ◽  
Author(s):  
Lucas R. Parent ◽  
David Onofrei ◽  
Dian Xu ◽  
Dillan Stengel ◽  
John D. Roehling ◽  
...  
Keyword(s):  
Liquid Crystalline ◽  
Spider Silk ◽  
Fiber Spinning ◽  
Fiber Formation ◽  
Natural Material ◽  
Physical Form ◽  
Spinning Process ◽  
Black Widow Spiders ◽  
Spider Silks

Many natural silks produced by spiders and insects are unique materials in their exceptional toughness and tensile strength, while being lightweight and biodegradable–properties that are currently unparalleled in synthetic materials. Myriad approaches have been attempted to prepare artificial silks from recombinant spider silk spidroins but have each failed to achieve the advantageous properties of the natural material. This is because of an incomplete understanding of the in vivo spidroin-to-fiber spinning process and, particularly, because of a lack of knowledge of the true morphological nature of spidroin nanostructures in the precursor dope solution and the mechanisms by which these nanostructures transform into micrometer-scale silk fibers. Herein we determine the physical form of the natural spidroin precursor nanostructures stored within spider glands that seed the formation of their silks and reveal the fundamental structural transformations that occur during the initial stages of extrusion en route to fiber formation. Using a combination of solution phase diffusion NMR and cryogenic transmission electron microscopy (cryo-TEM), we reveal direct evidence that the concentrated spidroin proteins are stored in the silk glands of black widow spiders as complex, hierarchical nanoassemblies (∼300 nm diameter) that are composed of micellar subdomains, substructures that themselves are engaged in the initial nanoscale transformations that occur in response to shear. We find that the established micelle theory of silk fiber precursor storage is incomplete and that the first steps toward liquid crystalline organization during silk spinning involve the fibrillization of nanoscale hierarchical micelle subdomains.

scholarly journals The remineralization potential of cocoa (Theobroma cacao) bean extract to increase the enamel micro hardness

2017 ◽  
Vol 29 (2) ◽  
Author(s):  
Sulistianingsih S. ◽  
Irmaleny I. ◽  
Opik Taofik Hidayat
Keyword(s):  
Theobroma Cacao ◽  
Vickers Microhardness ◽  
Tooth Enamel ◽  
Cocoa Bean ◽  
Natural Material ◽  
Micro Hardness ◽  
Synthetic Material ◽  
Fluorine Substitution ◽  
Average Value ◽  
Mineral Deposition

Introduction: Remineralization is the process of returning mineral ions into a hydroxyapatite structure characterized by mineral deposition on the enamel surface. The presence of mineral deposition would affect the microhardness of tooth enamel. Fluorine, as the remineralization agent is known with side effects such as fluorosis. Cocoa bean extract contains theobromine that can be used as an alternative remineralization ingredients. The objectives were to determine enamel microhardness after remineralization using cocoa bean extract as natural material and to compare with fluorine as synthetic material. Methods: Thirty-six maxillary first premolar tooth crowns was cut and planted in the epoxy resin. Teeth were then immersed in demineralization solution at pH 4 for 6 hours. The sample were divided into 2 groups, 18 for the fluorine group and the remaining group of cocoa extract. Vickers microhardness test was used before treatment, both after demineralized and remineralized. Results: The value of enamel microhardness before treatment in the fluorine group was 376.17 VHN as average value and the cocoa extract group was 357.33 VHN. After demineralization in fluorine group was 268.13 VHN and cocoa extract group was 235.93 VHN. After remineralization in fluorine group and cocoa extract group, respectively, 321.08 VHN and 293.86 VHN. The results of the analysis revealed that the level of enamel microhardness after remineralization was not significantly different in both groups (p>0.05). Conclusions: The findings indicated the ability of cocoa extract to increase the microhardness of enamel and implies the potential as a fluorine substitution for remineralization.

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