Potential of a Nigerian biotite-rich kaolinite ore to industrial alumina by hydrometallurgical process

Increasing demands for aluminium and aluminium oxide with diverse industrial applications have prompted the development of a low-cost and eco-friendly technique as a substitute for conventional ore treatments by reduction-roasting route, requiring high energy consumption. For example, the demand for high-grade industrial alumina (Al2O3) as valuable materials in refractories, pigments, adsorbents, catalysis, water purification, aluminium production and metallurgical applications cannot be over emphasized. Thus, the upgrading of a Nigerian biotite-rich kaolinite ore containing admixture of kaolinite (Al2.00Si2.00O9.00: 96-900-9231), biotite (Mg6.55Fe3.46Al5.29Ti1.34Si11.36K4.00O48.00: 96-900-0844) and quartz (Si3.00O6.00: 96-900-9667) impurities by hydrometallurgical route was investigated in phosphoric acid media. During leaching, parameters such as leachant concentration, particle size and reaction temperature on the extent of ore dissolution were accordingly examined. At optimal leaching conditions (2.0 mol/L H3PO4, 75 °C), 87.0% of the initial 10 g/L ore reacted within 120 min. The activation energy of 16.6 kJ/mol supported the diffusion control reaction mechanism. The unreacted product (∼13.0%) analyzed by XRD was found to contain siliceous impurities including iron silicate and manganese silicate which could serve as valuable by-products for some defined industries. The leach liquor at optimal leaching conditions was accordingly treated to obtain pure aluminium solution which was further beneficiated to obtain high-grade alumina (α-Al2O3) of industrial value with 96.3% purity.

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Transient Thermodynamic Modelling and Experimental Validation of an Antagonistic SMA Actuator

Smart Materials, Adaptive Structures and Intelligent Systems, Volume 1 ◽

10.1115/smasis2008-520 ◽

2008 ◽

Author(s):

Anupam Pathak ◽

Diann Brei ◽

Jonathan Luntz

Keyword(s):

Low Cost ◽

High Energy ◽

Industrial Applications ◽

High Yield ◽

Attractive Alternative ◽

Driving Frequency ◽

Physically Based ◽

Antagonistic Actuation ◽

High Production ◽

Key Aspects

Modern developments in Shape Memory Alloys (SMA) has positioned the material as an attractive alternative actuation for high yield, low cost industries which stand to benefit from the materials simple form, light weight, and high energy densities. However, the speed and predictability still remain as a barrier to its acceptance and usage. The robotics community has shown promising results with antagonistic actuation architectures to increase the cyclic speed and produce controlled motions; however, such control-based approaches generally require sensing and feedback implementations and tuning that are undesirable for high production products. This paper presents a simple but effective physically-based thermodynamic model for generic antagonistic actuation architecture. The model is derived from three sets of equations: differential equations describing the thermomechanical phase transformation behavior of the material, compatibility equations specific to the antagonistic configuration relating stresses and strains in the two wires to each other, and heat transfer equations involving the thermal properties of both the environment and the wire material. This model takes into consideration several key-aspects of real devices such as the wires becoming slack or localalized boiling conditions. This model was experimentally validated and studied under a range of conditions including variations in driving frequency (0.3–10 Hz), duty cycle (10%–45%), amplitude (50%–100% transformation), and wire diameter (8–20 mil). The correlation over these widely varying conditions indicates the model’s accuracy and potential for use in the design process of future antagonistic actuators and their controllers for industrial applications.

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Janus – A New Approach to Air Combat Pilot Training

Transactions on Aerospace Research ◽

10.2478/tar-2019-0019 ◽

2019 ◽

Vol 2019 (4) ◽

pp. 7-22

Author(s):

Georges Bridel ◽

Zdobyslaw Goraj ◽

Lukasz Kiszkowiak ◽

Jean-Georges Brévot ◽

Jean-Pierre Devaux ◽

...

Keyword(s):

Low Cost ◽

Cost Effective ◽

High Energy ◽

Training System ◽

Embedded Sensors ◽

Pilot Training ◽

New Approach ◽

Combat Aircraft ◽

Air Combat ◽

The Cost

Abstract Advanced jet training still relies on old concepts and solutions that are no longer efficient when considering the current and forthcoming changes in air combat. The cost of those old solutions to develop and maintain combat pilot skills are important, adding even more constraints to the training limitations. The requirement of having a trainer aircraft able to perform also light combat aircraft operational mission is adding unnecessary complexity and cost without any real operational advantages to air combat mission training. Thanks to emerging technologies, the JANUS project will study the feasibility of a brand-new concept of agile manoeuvrable training aircraft and an integrated training system, able to provide a live, virtual and constructive environment. The JANUS concept is based on a lightweight, low-cost, high energy aircraft associated to a ground based Integrated Training System providing simulated and emulated signals, simulated and real opponents, combined with real-time feedback on pilot’s physiological characteristics: traditionally embedded sensors are replaced with emulated signals, simulated opponents are proposed to the pilot, enabling out of sight engagement. JANUS is also providing new cost effective and more realistic solutions for “Red air aircraft” missions, organised in so-called “Aggressor Squadrons”.

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High-Energy-Density, Long-Life Lithium–Sulfur Batteries with Practically Necessary Parameters Enabled by Low-Cost Fe–Ni Nanoalloy Catalysts

ACS Nano ◽

10.1021/acsnano.1c00446 ◽

2021 ◽

Author(s):

Jiarui He ◽

Amruth Bhargav ◽

Arumugam Manthiram

Keyword(s):

Energy Density ◽

Low Cost ◽

High Energy ◽

High Energy Density ◽

Lithium Sulfur Batteries ◽

Long Life ◽

Lithium Sulfur

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Na0.76V6O15/Activated Carbon Hybrid Cathode for High-Performance Lithium-Ion Capacitors

Materials ◽

10.3390/ma14010122 ◽

2020 ◽

Vol 14 (1) ◽

pp. 122

Author(s):

Renwei Lu ◽

Xiaolong Ren ◽

Chong Wang ◽

Changzhen Zhan ◽

Ding Nan ◽

...

Keyword(s):

Activated Carbon ◽

Energy Density ◽

Power Density ◽

Cathode Materials ◽

Low Cost ◽

Lithium Ion ◽

High Energy ◽

Cycling Stability ◽

High Energy Density ◽

Artificial Graphite

Lithium-ion hybrid capacitors (LICs) are regarded as one of the most promising next generation energy storage devices. Commercial activated carbon materials with low cost and excellent cycling stability are widely used as cathode materials for LICs, however, their low energy density remains a significant challenge for the practical applications of LICs. Herein, Na0.76V6O15 nanobelts (NaVO) were prepared and combined with commercial activated carbon YP50D to form hybrid cathode materials. Credit to the synergism of its capacitive effect and diffusion-controlled faradaic effect, NaVO/C hybrid cathode displays both superior cyclability and enhanced capacity. LICs were assembled with the as-prepared NaVO/C hybrid cathode and artificial graphite anode which was pre-lithiated. Furthermore, 10-NaVO/C//AG LIC delivers a high energy density of 118.9 Wh kg−1 at a power density of 220.6 W kg−1 and retains 43.7 Wh kg−1 even at a high power density of 21,793.0 W kg−1. The LIC can also maintain long-term cycling stability with capacitance retention of approximately 70% after 5000 cycles at 1 A g−1. Accordingly, hybrid cathodes composed of commercial activated carbon and a small amount of high energy battery-type materials are expected to be a candidate for low-cost advanced LICs with both high energy density and power density.

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Optically transparent and very thin structure against electromagnetic pulse (EMP) using metal mesh and saltwater for shielding windows

Scientific Reports ◽

10.1038/s41598-021-80969-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Duy Tung Phan ◽

Chang Won Jung

Keyword(s):

Electromagnetic Pulse ◽

Low Cost ◽

High Energy ◽

Metal Plate ◽

Optical Transparency ◽

Shielding Effectiveness ◽

Concrete Wall ◽

Metal Mesh ◽

Wide Range ◽

Optically Transparent

AbstractAn electromagnetic pulse (EMP) with high energy can damage electronic equipment instantly within a wide range of thousands of kilometers. Generally, a metal plate placed inside a thick concrete wall is used against an EMP, but it is not suitable for an EMP shielding window, which requires not only strong shielding effectiveness (SE) but also optical transparency (OT). In this paper, we propose a very thin and optically transparent structure with excellent SE for EMP shielding window application. The proposed structure consists of a saltwater layer held between two glass substrates and two metal mesh layers on the outside of the glass, with a total thickness of less than 1.5 cm. The SE and OT of the structure are above 80 dB and 45%, respectively, which not only meet the requirement of EMP shielding for military purposes but also retain the procedure of good observation. Moreover, the OT of the structure can be significantly improved using only one metal mesh film (MMF) layer, while the SE is still maintained high to satisfy the required SE for home applicants. With the major advantages of low cost, optical transparency, strong SE, and flexible performance, the proposed structure can be considered a good solution for transparent EMP shielding windows.

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IoT Platform for Energy Sustainability in University Campuses

Sensors ◽

10.3390/s21020357 ◽

2021 ◽

Vol 21 (2) ◽

pp. 357

Author(s):

Pedro Moura ◽

José Ignacio Moreno ◽

Gregorio López López ◽

Manuel Alvarez-Campana

Keyword(s):

Energy Demand ◽

New Technologies ◽

Low Cost ◽

Sustainable Use ◽

High Energy ◽

Appropriate Technology ◽

Monitoring And Control ◽

Energy Sustainability ◽

University Campuses ◽

Iot Platform

University campuses are normally constituted of large buildings responsible for high energy demand, and are also important as demonstration sites for new technologies and systems. This paper presents the results of achieving energy sustainability in a testbed composed of a set of four buildings that constitute the Telecommunications Engineering School of the Universidad Politécnica de Madrid. In the paper, after characterizing the consumption of university buildings for a complete year, different options to achieve more sustainable use of energy are presented, considering the integration of renewable generation sources, namely photovoltaic generation, and monitoring and controlling electricity demand. To ensure the implementation of the desired monitoring and control, an internet of things (IoT) platform based on wireless sensor network (WSN) infrastructure was designed and installed. Such a platform supports a smart system to control the heating, ventilation, and air conditioning (HVAC) and lighting systems in buildings. Furthermore, the paper presents the developed IoT-based platform, as well as the implemented services. As a result, the paper illustrates how providing old existing buildings with the appropriate technology can contribute to the objective of transforming such buildings into nearly zero-energy buildings (nZEB) at a low cost.

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Remote Reflectivity Sensor for Industrial Applications

Sensors ◽

10.3390/s21041301 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1301

Author(s):

Federico Cavedo ◽

Parisa Esmaili ◽

Michele Norgia

Keyword(s):

Low Cost ◽

Cost Effective ◽

Industrial Applications ◽

Interference Immunity ◽

Surface Reflection ◽

Measurement Systems ◽

Digital Detector ◽

Reflected Light ◽

Surface Optical ◽

Diffused Light

A low-cost optical reflectivity sensor is proposed in this paper, able to detect the presence of objects or surface optical properties variations, at a distance of up to 20 m. A collimated laser beam is pulsed at 10 kHz, and a synchronous digital detector coherently measures the back-diffused light collected through a 1-inch biconvex lens. The sensor is a cost-effective solution for punctual measurement of the surface reflection at different distances. To enhance the interference immunity, an algorithm based on a double-side digital baseline restorer is proposed and implemented to accurately detect the amplitude of the reflected light. As results show, the sensor is robust against ambient light and shows a strong sensitivity on a wide reflection range. The capability of the proposed sensor was evaluated experimentally for object detection and recognition, in addition to dedicated measurement systems, like remote encoders or keyphasors, realized far from the object to be measured.

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Deconstruction of Lignin: From Enzymes to Microorganisms

Molecules ◽

10.3390/molecules26082299 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2299

Author(s):

Jéssica P. Silva ◽

Alonso R. P. Ticona ◽

Pedro R. V. Hamann ◽

Betania F. Quirino ◽

Eliane F. Noronha

Keyword(s):

Microbial Communities ◽

Metabolic Pathways ◽

Low Cost ◽

Direct Analysis ◽

Industrial Applications ◽

Natural Environments ◽

Lignocellulosic Residues ◽

Complementary Techniques ◽

Plant Polymer ◽

Powerful Strategy

Lignocellulosic residues are low-cost abundant feedstocks that can be used for industrial applications. However, their recalcitrance currently makes lignocellulose use limited. In natural environments, microbial communities can completely deconstruct lignocellulose by synergistic action of a set of enzymes and proteins. Microbial degradation of lignin by fungi, important lignin degraders in nature, has been intensively studied. More recently, bacteria have also been described as able to break down lignin, and to have a central role in recycling this plant polymer. Nevertheless, bacterial deconstruction of lignin has not been fully elucidated yet. Direct analysis of environmental samples using metagenomics, metatranscriptomics, and metaproteomics approaches is a powerful strategy to describe/discover enzymes, metabolic pathways, and microorganisms involved in lignin breakdown. Indeed, the use of these complementary techniques leads to a better understanding of the composition, function, and dynamics of microbial communities involved in lignin deconstruction. We focus on omics approaches and their contribution to the discovery of new enzymes and reactions that impact the development of lignin-based bioprocesses.

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A High-Performance Free-Standing Zn Anode for Flexible Zinc-Ion Batteries

Nanoscale ◽

10.1039/d1nr01266e ◽

2021 ◽

Author(s):

Chenxi Gao ◽

Jiawei Wang ◽

Yuan Huang ◽

Zixuan Li ◽

Jiyan Zhang ◽

...

Keyword(s):

Energy Density ◽

High Performance ◽

Low Cost ◽

High Energy ◽

Zinc Ion ◽

High Energy Density ◽

Free Standing ◽

Energy Device ◽

Zn Anode ◽

Significant Attention

Zinc-ion batteries (ZIBs) have attracted significant attention owing to their high safety, high energy density, and low cost. ZIBs have been studied as a potential energy device for portable and...

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