scholarly journals Xerogel-like Materials from Sustainable Sources: Properties and Electrochemical Performances

Energies ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7977
Author(s):  
Gisele Amaral-Labat ◽  
Manuella Gobbo C. Munhoz ◽  
Beatriz Carvalho da Silva Fonseca ◽  
Alan Fernando Ney Boss ◽  
Patricia de Almeida-Mattos ◽  
...  
Keyword(s):  
Porous Carbon ◽  
Cost Reduction ◽  
State Of The Art ◽  
Textural Properties ◽  
Electrochemical Performances ◽  
Renewable Materials ◽  
Carbon Xerogel ◽  
Bio Oil ◽  
Fast Charging ◽  
Long Lifetime

Energy storage is currently one of the most significant technological challenges globally, and supercapacitor is a prominent candidate over batteries due to its ability for fast charging and long lifetime. Supercapacitors typically use porous carbon as electrodes, because of both the high conductivity and surface area of the material. However, the state-of-the-art porous carbon described in the literature uses toxic chemicals and complex procedures that enhance costs and pollute the environment. Thus, a more sustainable procedure to produce porous carbon is highly desirable. In this context, xerogel-like carbons were prepared by a new, cheap, simple route to polymerization reactions of tannin-formaldehyde in a bio-oil by-product. Using bio-oil in its natural pH allowed a cost reduction and avoided using new reactants to change the reactional medium. Textural properties and electrochemical performances were improved by fast activating the material per 20 min. The non-activated carbon xerogel presented a capacitance of 92 F/g, while the activated one had 132 F/g, given that 77% of the components used are eco-friendly. These results demonstrate that renewable materials may find applications as carbon electrodes for supercapacitors. Overhauling the synthesis route with a different pH or replacing formaldehyde may enhance performance or provide a 100% sustainable carbon electrode.

scholarly journals A secure and highly efficient first-order masking scheme for AES linear operations

Cybersecurity ◽  
2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Jingdian Ming ◽  
Yongbin Zhou ◽  
Huizhong Li ◽  
Qian Zhang
Keyword(s):  
Cost Reduction ◽  
Provable Security ◽  
State Of The Art ◽  
Side Channel ◽  
First Order ◽  
Highly Efficient ◽  
Non Linear ◽  
Device Independence ◽  
Practical Implications ◽  
Provably Secure

AbstractDue to its provable security and remarkable device-independence, masking has been widely accepted as a noteworthy algorithmic-level countermeasure against side-channel attacks. However, relatively high cost of masking severely limits its applicability. Considering the high tackling complexity of non-linear operations, most masked AES implementations focus on the security and cost reduction of masked S-boxes. In this paper, we focus on linear operations, which seems to be underestimated, on the contrary. Specifically, we discover some security flaws and redundant processes in popular first-order masked AES linear operations, and pinpoint the underlying root causes. Then we propose a provably secure and highly efficient masking scheme for AES linear operations. In order to show its practical implications, we replace the linear operations of state-of-the-art first-order AES masking schemes with our proposal, while keeping their original non-linear operations unchanged. We implement four newly combined masking schemes on an Intel Core i7-4790 CPU, and the results show they are roughly 20% faster than those original ones. Then we select one masked implementation named RSMv2 due to its popularity, and investigate its security and efficiency on an AVR ATMega163 processor and four different FPGA devices. The results show that no exploitable first-order side-channel leakages are detected. Moreover, compared with original masked AES implementations, our combined approach is nearly 25% faster on the AVR processor, and at least 70% more efficient on four FPGA devices.

scholarly journals Inlet and Nozzle Technology for 21st Century Fighter Aircraft

1996 ◽  
Author(s):  
Marvin C. Gridley ◽  
Steven H. Walker
Keyword(s):  
21St Century ◽  
Cost Reduction ◽  
State Of The Art ◽  
Aerodynamic Performance ◽  
Innovative Technology ◽  
Fighter Aircraft ◽  
Current State ◽  
Aircraft System ◽  
Year 2000 ◽  
System Volume

The focus of propulsion integration technology in the 21st century will be economy. USAF inlet and nozzle technology goals translate into 50% weight reduction and 25% acquisition cost reduction metrics for new aircraft system. Innovative technology to enable these reductions over current state-of-the-art systems in weight and cost is required. For inlet systems, compact diffusers that reduce system volume by 50% will demand fewer parts and improved aerodynamic performance. Exhaust systems will be fixed with fewer parts, requiring a technology like fluidics, for example, to provide area control and thrust vectoring capabilities. Cooperative programs for both inlet and nozzle systems are in place to insure that technologies required to meet weight and cost reduction goals are matured by the year 2000.

Biosourced, highly porous, carbon xerogel microspheres

RSC Advances ◽  
2016 ◽  
Vol 6 (70) ◽  
pp. 65698-65708 ◽  
Author(s):  
L. I. Grishechko ◽  
G. Amaral-Labat ◽  
V. Fierro ◽  
A. Szczurek ◽  
B. N. Kuznetsov ◽  
...  
Keyword(s):  
Porous Carbon ◽  
Carbon Xerogel ◽  
Highly Porous

The first tannin-based carbon xerogel microspheres were prepared and characterised.

Hierarchical porous carbon microtubes derived from willow catkins for supercapacitor applications

2016 ◽  
Vol 4 (5) ◽  
pp. 1637-1646 ◽  
Author(s):  
Lijing Xie ◽  
Guohua Sun ◽  
Fangyuan Su ◽  
Xiaoqian Guo ◽  
Qingqiang Kong ◽  
...  
Keyword(s):  
Porous Carbon ◽  
Electrochemical Performances ◽  
Hierarchical Porous Carbon ◽  
Organic Electrolytes ◽  
Hierarchical Porous ◽  
Supercapacitor Applications

Hierarchical porous carbon microtubes derived from willow catkins exhibited excellent electrochemical performances in both aqueous and organic electrolytes.

Enabling Requirements for High Volume Thermo compression Bonding

2015 ◽  
Vol 2015 (DPC) ◽  
pp. 000995-001015
Author(s):  
Tom Strothmann
Keyword(s):  
Process Control ◽  
Cost Reduction ◽  
State Of The Art ◽  
High Volume ◽  
Manufacturing Technology ◽  
Data Logging ◽  
Key Factors ◽  
Review State ◽  
Memory Applications

The potential of Thermo compression Bonding (TCB) has been widely discussed for several years, but it has not previously achieved widespread production use. TCB has now begun the transition to an accepted high volume manufacturing technology driven primarily by the memory market, but with wider adoption close for non-memory applications. Several key factors have enabled this transition, including advanced TCB equipment with higher UPH for cost reduction and advanced methods of inline process control. The unique requirements of TCB demand absolute process control, simultaneous data logging capability for multiple key factors in the process and portability of the process between tools. This introduces a level of sophistication that has not previously been required for BE assembly processes. This presentation will review state of the art TCB technology and the fundamental equipment requirements to support the transition to HVM.

scholarly journals Advanced Electric Vehicle Fast-Charging Technologies

Energies ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1839 ◽  
Author(s):  
Ryan Collin ◽  
Yu Miao ◽  
Alex Yokochi ◽  
Prasad Enjeti ◽  
Annette von Jouanne
Keyword(s):  
Electric Vehicle ◽  
State Of The Art ◽  
Power Electronic ◽  
Heat Management ◽  
Battery Charging ◽  
Fast Charging ◽  
Battery Systems ◽  
Converter Topologies ◽  
Negative Impacts ◽  
Power Electronic Converter

Negative impacts from the dominant use of petroleum-based transportation have propelled the globe towards electrified transportation. With this thrust, many technological challenges are being encountered and addressed, one of which is the development and availability of fast-charging technologies. To compete with petroleum-based transportation, electric vehicle (EV) battery charging times need to decrease to the 5–10 min range. This paper provides a review of EV fast-charging technologies and the impacts on the battery systems, including heat management and associated limitations. In addition, the paper presents promising new approaches and opportunities for power electronic converter topologies and systems level research to advance the state-of-the-art in fast-charging.

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