scholarly journals High Temperature Metamaterial Enhanced Electromagnetic Absorbing Coating Prepared With Alumina Ceramic 

2021 ◽  
Author(s):  
Shixin Zhao ◽  
Hua Ma ◽  
Tengqiang Shao ◽  
Jun Wang ◽  
Zhaoning Yang ◽  
...  
Keyword(s):  
High Temperature ◽  
Screen Printing ◽  
Large Scale ◽  
Raw Materials ◽  
Impedance Matching ◽  
Alumina Ceramic ◽  
Raw Material ◽  
Pure Alumina ◽  
Complex Preparation ◽  
Absorption Performance

Abstract At present, a series of challenges are impeding the large-scale application of the high temperature radar absorbing coatings (RACs), such as the complex preparation of raw material and the complicated technology of processing. In this paper, a new, thin and high-temperature metamaterial RAC (MRAC) with strong absorption was designed and experimentally demonstrated, composing of a radar absorbing coating and a layer of metamaterial. To avoid the need for the complex preparation of raw materials, pure alumina was selected as the radar absorbing coating. Meanwhile, plasma spraying and screen printing were employed to simplify the manufacture technology to produce the absorbing coating and the metamaterial layer, ensuring its feasibility and practicality. The metamaterial layer was prepared with a high temperature conductive paste and it improved the impedance matching of the coating and regulated the electromagnetic (EM) resonance. With the ability to consume more incident EM waves, excellent absorption performance at high temperature was achieved with relatively small thickness. In the 8 ~ 18 GHz band, the MRAC bandwidth for reflection loss (RL) below -5dB almost covered the frequency of 10 ~18 GHz with a thickness of only 1.5 mm at 800 ℃. This new metamaterial has broad application prospects by the virtue of its simplicity and ease of production.

scholarly journals Properties dependence of the lightweight alumina products obtained by a semi-dry pressing method on the alumina type

2020 ◽  
Vol 120 ◽  
pp. 126-133
Author(s):  
V. V. Martynenko ◽  
Yu. A. Krakhmal ◽  
K. I. Kushchenko ◽  
T. G. Tishina
Keyword(s):  
Phase Composition ◽  
High Temperature ◽  
Raw Materials ◽  
Raw Material ◽  
Pressing Method ◽  
Technical Requirements ◽  
Alumina Grade ◽  
Pitch Coke ◽  
Calcium Hexaluminate ◽  
Dry Pressing

Lightweight materials are widely used in industry for thermal insulation of various thermal units. The choice of lightweight material depends on the specific conditions of service. For the lining of high-temperature units operating in reducing environments, alumina lightweight products are used that contain a minimum amount of Fe2O3 impurities and free (unbound in compounds) SiO2. In JSC “URIR named after A. S. Berezhnoy” a technology of alumina lightweight products of grades KLA-1.1 and KLA-1.3 by a semi-dry pressing method with an application temperature of up to 1550 °C has been developed. These products are made from a mixture of ground and no-milled γ-form alumina of grade 0 and α-form alumina of grade S with additives of pitch coke and chalk. The work purpose was improvement of the alumina lightweight products technology and search for new alternative raw materials along with the currently used alumina grade S. The properties dependence of alumina lightweight products, obtained by the semi-dry pressing method, on the type of alumina α-form, was investigated. As a result of the studies, it was found that, for the manufacture of alumina lightweight products of grades KLA-1.1 and KLA-1.3 by the semi-dry pressing method, alumina grades N and NR can be used as an alternative alumina-containing raw material along with alumina grade S. The phase composition of alumina lightweight products of grades KLA-1.1 and KLA-1.3, which are manufactured using alumina grades S, N and NR, was represented mainly by corundum and calcium hexaluminate. The alumina lightweight products, which were manufactured using alumina grades S, N and NR, were characterized by similar high properties and correspond the technical requirements for grades KLA-1.1 and KLA-1.3.

Optimal Design and Techno-Economic Analysis for Corncob Particles Briquettes: A Literature Review of the Utilization of Agricultural Waste and Analysis Calculation

2021 ◽  
Author(s):  
Asep Bayu Dani Nandiyanto ◽  
Nissa Nur Azizah ◽  
Gabriela Chelvina Santiuly Girsang
Keyword(s):  
Optimal Design ◽  
Literature Review ◽  
Economic Analysis ◽  
Large Scale ◽  
Net Present Value ◽  
Raw Materials ◽  
Agricultural Waste ◽  
Raw Material ◽  
Variable Cost ◽  
Scale Production

Corncob is usually disposed of directly as waste, creating problems in the environment, while it can be converted into valuable materials. This research aimed to evaluate the literature review on briquette production from agricultural waste (using non-binder and cold press with a binder) and the current works on techno-economic analysis, to propose an optimal design for the production of briquette from corncob waste, and to perform a techno-economic analysis based on the selected optimal processing method. The engineering perspective based on stoichiometry and mass balance showed the potential corncob briquette manufacture in both home and large scales due to the possible use of inexpensive and commercially available equipment and raw materials. The economic perspective [based on several economic evaluation factors (i.e., gross profit margin, payback period, break-even point, cumulative net present value, return of investment, internal rate return, and profitability index) under ideal and non-ideal conditions by considering internal (i.e., sales, raw materials, utilities, and variable cost) and external aspects (i.e., tax)] confirmed the prospective development of the project in the large-scale production with a lifetime of more than 18 years. The main issue in the project is the raw material (i.e. tapioca flour), giving the most impact on the project’s feasibility. Even in severe conditions, the project is feasible. The great endurance was also confirmed in the case of a higher tax rate. This study demonstrates the importance of producing corncob-based briquettes for improving the economic value and giving alternatives for problem solvers in the utilization of agricultural waste.

scholarly journals Problems of mineral raw material losses of quality and quantity management in developing of large-scale complex-structure deposits.

2018 ◽  
Vol 56 ◽  
pp. 04003
Author(s):  
Sergei Tkach
Keyword(s):  
Large Scale ◽  
Raw Materials ◽  
Complex Structure ◽  
Raw Material ◽  
Qualitative And Quantitative ◽  
Mineral Raw Material ◽  
Regulatory Documents ◽  
Geological Conditions ◽  
High Degree ◽  
Very High

The article deals with the problems of mineral raw material losses of quality and quantity management in developing of large-scale complex-structure and composition deposits of solid minerals. It is shown that a very high degree of mining and geological conditions variability in time and space for the development of mining units is typical for such deposits. This significantly complicates the qualitative and quantitative operating losses setting and accounting of mineral raw materials during its extraction in the framework of existing general and industry regulatory documents. Conceptual principles for face-by-face operational setting of losses and impoverishment of minerals for the conditions of bulk mining of complex-structure deposits with the formation of gross mining flow with economically feasible and specified level of quality (the content of commercial and harmful components) are stated. These principles generally do not contradict effective instructions main provisions and are made to minimize the total operating losses during the processing of several mine sections (faces).

scholarly journals TLS and SfM Approach for Bulk Density Determination of Excavated Heterogeneous Raw Materials

Minerals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 174 ◽  
Author(s):  
Peter Blistan ◽  
Stanislav Jacko ◽  
Ľudovít Kovanič ◽  
Julián Kondela ◽  
Katarína Pukanská ◽  
...  
Keyword(s):  
Bulk Density ◽  
Laser Scanning ◽  
Large Scale ◽  
Raw Materials ◽  
Terrestrial Laser Scanning ◽  
Mineral Resources ◽  
Point Clouds ◽  
Raw Material

A frequently recurring problem in the extraction of mineral resources (especially heterogeneous mineral resources) is the rapid operative determination of the extracted quantity of raw material in a surface quarry. This paper deals with testing and analyzing the possibility of using unconventional methods such as digital close-range photogrammetry and terrestrial laser scanning in the process of determining the bulk density of raw material under in situ conditions. A model example of a heterogeneous deposit is the perlite deposit Lehôtka pod Brehmi (Slovakia). Classical laboratory methods for determining bulk density were used to verify the results of the in situ method of bulk density determination. Two large-scale samples (probes) with an approximate volume of 7 m3 and 9 m3 were realized in situ. 6 point samples (LITH) were taken for laboratory determination. By terrestrial laser scanning (TLS) measurement from 2 scanning stations, point clouds with approximately 163,000/143,000 points were obtained for each probe. For Structure-from-Motion (SfM) photogrammetry, 49/55 images were acquired for both probes, with final point clouds containing approximately 155,000/141,000 points. Subsequently, the bulk densities of the bulk samples were determined by the calculation from in situ measurements by TLS and SfM photogrammetry. Comparison of results of the field in situ measurements (1841 kg∙m−3) and laboratory measurements (1756 kg∙m−3) showed only a 4.5% difference in results between the two methods for determining the density of heterogeneous raw materials, confirming the accuracy of the used in situ methods. For the determination of the loosening coefficient, the material from both large-scale samples was transferred on a horizontal surface. Their volumes were determined by TLS. The loosening coefficient for the raw material of 1.38 was calculated from the resulting values.

Microbial Oil Production from Lignocellulosic Biomass – Recent Development and Prospect

2014 ◽  
Vol 541-542 ◽  
pp. 397-403
Author(s):  
Zhang Nan Lin ◽  
Hong Juan Liu ◽  
Zhi Qin Wang ◽  
Jia Nan Zhang
Keyword(s):  
Lignocellulosic Biomass ◽  
Large Scale ◽  
Raw Materials ◽  
Oil Production ◽  
Renewable Resource ◽  
Raw Material ◽  
Biodiesel Production ◽  
Microbial Oil ◽  
Key Issues ◽  
Application Potential

Microbial oil is one of the ideal raw materials for biodiesel production because of its rapid reproduction and less influence by the climate and season variation. However, the high cost is one of the key issues that restricted its production in a large-scale. Lignocellulosic biomass, the cheap and renewable resource, might be the best raw material for microbial oil production by oleaginous microorganisms. Recent development on the microbial oil production from lignocellulosic biomass was summarized in this paper. Furthermore, the challenges and application potential of microbial oil were prospected.

Preparation and Properties of MgAl2O4-CaAl12O19 High Temperature Composite

2012 ◽  
Vol 512-515 ◽  
pp. 617-620
Author(s):  
Yong Hong Wang ◽  
Yan Gai Liu ◽  
Tao Yang ◽  
Zhao Hui Huang ◽  
Ming Hao Fang
Keyword(s):  
Phase Composition ◽  
High Temperature ◽  
Reaction Temperature ◽  
Bending Strength ◽  
Raw Materials ◽  
Weight Ratio ◽  
Raw Material ◽  
Reaction Conditions ◽  
Optimum Reaction ◽  
Industrial Alumina

The utilization of lightweight refractories plays an important role in reducing the energy consumption of industrial furnaces. In this paper, MgAl2O4-CaA112O19 high temperature composite was synthesized via solid state reaction using magnesite, dolomite and industrial alumina as raw materials. The influences of raw materials and reaction temperature on phase compositions and microstructure of the composite were investigated by XRD and SEM，respectively. The parameters to prepare MgAl2O4-CaA112O19 high temperature composite were optimized. The results show that the optimum reaction conditions for synthesizing MgAl2O4-CaA112O19 composite is the CA6/MA weight ratio of 2:3, and the reaction temperature of 1500°C for 4h. The CaA112O19 crystals showed laminated or plate-like structure, and the MgAl2O4 showed spherical morphology. The reaction temperature had little effect on the phase compositions of MA-CA6 composite in this experiment. The content of Al2O3 in the raw material affected the phase composition of MA-CA6 composite.With the increase of the CaA112O19 amount, the bending strength of the composite decreased.

scholarly journals Efficient use of microwave EMF and multilevel high temperature sterilization modes in apple puree technology for dietetic nutrition

2020 ◽  
Vol 222 ◽  
pp. 03005
Author(s):  
M.M. Rakhmanova ◽  
A.F. Demirova ◽  
M.E. Akhmedov ◽  
Z.A. Abdulkhalikov ◽  
T.N. Daudova
Keyword(s):  
Heat Treatment ◽  
High Temperature ◽  
Raw Materials ◽  
Nutrient Composition ◽  
Raw Material ◽  
Saturated Steam ◽  
Technical Data ◽  
Short Time ◽  
Apple Puree ◽  
Apple Purée

The article is dedicated to improving the quality of apple puree with xylitol for dietetic nutrition due to the development and implementation of a new technological process. This is microwave boiling of apples, rather than traditional steaming using saturated steam before chopping, with the development of a device for its implementation and multilevel high-temperature sterilization modes with prebake of apple puree in glass jars in microwave EMF. The analysis of research and technical data proved that pre-heat treatment of apples with saturated steam and traditional sterilization modes have a considerable duration, which impairs the finished products quality and has an adverse effect on the nutrient composition of the raw material during processing. Substituting the traditional method of pre-heat treatment of apples for their short-time processing in microwave EMF reduces the process by more than twice, which, in turn, contributes to an increased preservation of the nutrient composition of apples, while enhancing the yield of apple puree. For the implementation of microwave processing method of raw materials, a new design of the device for electromagnetic treatment of plant roughage has been developed, providing a uniform and more intensive heat treatment of raw materials in a continuous flow. Rapid multilevel high-temperature sterilization modes with the application of apple puree in glass jars in microwave EMF, liquid high-temperature heat devices and an autoclave basket, providing the opportunity for thermal sterilization of the product without creating reverse pressure in the machine, generally contribute to reducing heat costs and increasing the nutritional value.

scholarly journals Transparency with Blockchain and Physical Tracking Technologies: Enabling Traceability in Raw Material Supply Chains

2021 ◽  
Vol 5 (1) ◽  
pp. 1
Author(s):  
Angela v. Beckh Bacchetta ◽  
Volker Krümpel ◽  
Ella Cullen
Keyword(s):  
Literature Review ◽  
Supply Chains ◽  
Large Scale ◽  
Raw Materials ◽  
Physical World ◽  
Raw Material ◽  
Global Supply Chains ◽  
Academic Literature ◽  
Material Supply ◽  
Digital World

By combining blockchain with physical tracking technologies, raw materials can potentially be traced throughout their global supply chains. Physical tracking technologies enable observing how raw materials move within the physical world, whereas blockchain translates these events into the digital world with an immutable record. This paper presents a taxonomy of different physical tracking technologies and examines if and how the combination of these technologies render raw material supply chains more transparent. Although academic literature highlights the theoretical benefits of combining these transformative technologies, large scale projects are still in their early stages. Following a brief literature review, this paper leverages an empirical approach to classify different tracking technologies, their fields of application and limitations, as well as how these technologies can enable supply chain transparency. Obviously, there is no single technology that can fulfil all requirements along complex supply chains. However, the relevant combination of respective technologies can help bridge gaps by increasing transparency within supply chains.

scholarly journals Method for the Production of Fat from Raw Materials and Animal Waste

2021 ◽  
Author(s):  
Ruslan Maratbekovich Iskakov ◽  
Assel Maratbekovna Iskakova ◽  
Murat Zhusypbekovich Nurushev ◽  
Altyngul Kumashevna Khaimuldinova ◽  
Nurlan Kazhkenovich Karbayev
Keyword(s):  
High Temperature ◽  
Raw Materials ◽  
Orange Peel ◽  
Primary Component ◽  
Raw Material ◽  
Animal Origin ◽  
Animal Waste ◽  
Degree Of Hydrolysis ◽  
Phase System ◽  
Two Phase

The aim of this article was to study degreasing of raw materials raw fish bone waste and animal waste. A new method was developed, aimed at intensive extraction of fat with an additional absorber- de-limonene, placed in water during high-temperature cooking of raw materials of animal origin. De-limonene is a widespread terpene hydrocarbon, and a primary component of orange peel oil (constitutes up to 80–90%). Degreasing with the inclusion of de-limonene increases the degree of hydrolysis of collagen from animal raw materials, which intensifies the extraction of fat from the processed raw materials. High-temperature cooking promotes the breakdown of triglycerides into free fatty acids, which further break down into low molecular weight products. At the end of the heat the temperature of the heating plates is 70-90 ° C, the pressure inside the boiler is 1.6,-2.4 kPa, the duration is 60-100 minutes treatment of the raw material, a two-phase system was obtained: dry fat greaves and fat. Fat was sucked off by pumps connected to digesters, and greasy greaves were sent for degreasing by pressing. The method produced broth, fat, and feed.

scholarly journals Biosurfactants – Nature's Solution for Today's Cleaning Challenges

2021 ◽  
Vol 75 (9) ◽  
pp. 752-756
Author(s):  
Jakob J. Mueller ◽  
Hans H. Wenk
Keyword(s):  
Large Scale ◽  
Raw Materials ◽  
Biological Molecules ◽  
Raw Material ◽  
Scale Production ◽  
Sustainable Solutions ◽  
Natural Substances ◽  
Head Groups ◽  
Large Scale Production ◽  
Recent Developments

Biosurfactants are surface-active molecules, developed by nature through evolution and naturally produced by different microorganisms. The most prominent examples are rhamnolipids and sophorolipids, molecules which contain hydrophilic sugar head groups and hydrophobic alkyl residues leading to an amphiphilic behavior with unique properties. Recent developments in the field of biotechnology enable the large-scale production of these biological molecules. The raw material basis is 100% renewable since sugars and oils are used as major raw materials. Additionally, biosurfactants are fully biodegradable, which allows the path back into the natural cycles. In comparison to established standard surfactants like SLES/SLS (sodium laureth (ether) sulfates) or betaines, rhamnolipids are much milder and, at the same time, show similar or even better performance in household or personal care applications. Foam behavior, solubilization and cleaning effectiveness are examples where these natural substances give excellent results compared to the synthetic benchmarks. The commercialization of biosurfactants at industrial scale now offers alternatives to consumers seeking sustainable solutions, without compromising performance. Biosurfactants combine both and set a new standard for surfactant applications.

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