scholarly journals Graphene production by cracking

2021 ◽  
Vol 379 (2203) ◽  
pp. 20200293 ◽  
Author(s):  
Sivasambu Bohm ◽  
Avinash Ingle ◽  
H. L. Mallika Bohm ◽  
Benji Fenech-Salerno ◽  
Shuwei Wu ◽  
...  
Keyword(s):  
High Pressure ◽  
Weight Ratio ◽  
Cost Effective ◽  
Industrial Applications ◽  
Lower Number ◽  
Production Methods ◽  
Number Of Layers ◽  
Two Dimensional Materials ◽  
Graphene Production

In recent years, graphene has found its use in numerous industrial applications due to its unique properties. While its impermeable and conductive nature can replace currently used anticorrosive toxic pigments in coating systems, due to its large strength to weight ratio, graphene can be an important component as a next-generation additive for automotive, aerospace and construction applications. The current bottlenecks in using graphene and graphene oxide and other two-dimensional materials are the availability of cost-effective, high-quality materials and their effective incorporation (functionalization and dispersion) into the product matrices. On overcoming these factors, graphene may attract significant demands in terms of volume consumption. Graphene can be produced on industrial scales and through cost-effective top-down routes such as chemical, electrochemical and/or high-pressure mechanical exfoliation. Graphene, depending on end applications, can be chemically tuned and modified via functionalization so that easy incorporation into product matrices is possible. This paper discusses different production methods and their impact on the quality of graphene produced in terms of energy input. Graphene with an average thickness below five layers was produced by both methods with varied defects. However, a higher yield of graphene with a lower number of layers was produced via the high-pressure exfoliation route. This article is part of a discussion meeting issue ‘A cracking approach to inventing new tough materials: fracture stranger than friction’.

Magnesium Twin-Roll Casting Technology for Flat and Long Products - State of the Art and Future

2018 ◽  
Vol 941 ◽  
pp. 1431-1436 ◽  
Author(s):  
Rudolf Kawalla ◽  
Madlen Ullmann ◽  
Thorsten Henseler ◽  
Ulrich Prahl
Keyword(s):  
Magnesium Alloys ◽  
Weight Ratio ◽  
Cost Effective ◽  
Industrial Applications ◽  
Industrial Construction ◽  
Twin Roll Casting ◽  
Current State ◽  
Roll Casting ◽  
Structural Applications ◽  
Twin Roll

Due to their advantageous strength-weight ratio, good recyclability, excellent noise and vibration damping properties as well as excellent dent resistance, magnesium materials offer a variety of uses in modern lightweight structures. As a result, a comeback of magnesium alloys is to be seen in multiple industrial applications, especially in the automotive industry, as the potential for lightweight, cost-effective lightweight industrial construction associated with the lightest metallic engineering material helps to meet even stricter energy and environmental efficiency guidelines. Traditionally, casting processes have been the dominant magnesium manufacturing processes, but in the last decade, an increasing number of lightweight structural applications have been implemented with magnesium wrought alloys. In this paper, the current state of developments focusing the twin-roll casting (TRC) of semi-finished products of magnesium alloys will be presented. By reducing the number of process steps in combination with a unique microstructure, the near-net-shape TRC process offers new options to provide magnesium materials meeting current and future requirements for semi-finished products, constructions and moldings in terms of type, quantity and quality.

Influence of mineral elements on the yield and quality of grain of the prospective line in winter tritikale

2020 ◽  
Author(s):  
I.N. Voronchikhina ◽  
◽  
A.G. Marenkova ◽  
V. S. Rubets ◽  
V. V. Pylnev
Keyword(s):  
Cost Effective ◽  
Mineral Elements ◽  
Early Spring ◽  
High Potential ◽  
Winter Triticale ◽  
Yield And Quality ◽  
Fertilizer System

The results of elements development of varietal agrotechnics of a new high-potential line 238h of winter triticale presented. It was identified that under the conditions of 2020 the most cost effective fertilizer system is an early spring application of NPK (S) (15-15-15 (10)) at a dose of 200kg/ha. The profitability level of this fertilizer was 88,9%.

Regulatory Issues in Pakistan Telecommunication

1998 ◽  
Vol 37 (4II) ◽  
pp. 873-882 ◽  
Author(s):  
Sarfaraz Khan Quershi
Keyword(s):  
National Economy ◽  
Cost Effective ◽  
Market Forces ◽  
Global Trends ◽  
Regulatory Issues ◽  
Competitive Price ◽  
Modern Services ◽  
A Company ◽  
Telecom Infrastructure

Growth in telecom infrastructure and provision of modern telecom services to consumers at a cost based tariff helps growth of national economy. Modern telecoms serve as the engine of growth of national economy. Following the global trends of liberalisation and deregulation in telecoms monopolies which have thus far been providing inefficient communication at a greedily high tariffs are falling apart. Mergers in telecoms are not for increasing the size of the monopoly but to provide more efficient and cost effective services to the consumers. In Pakistan the erstwhile T&T department played a needful role at its time. Conversion of the department into a corporation and then into a company were steps necessary for following the global trends. Need now is to continue this trend further, eliminate the monopolistic approach by allowing more players in the field thus permitting the market forces to decide the provision of better quality of modern services at competitive price.

A Sample Preparation on Decapsulation Methodology for Effective Failure Analysis on Thin Small Leadless (TSLP) Flip Chip Package with Copper Pillar (CuP) Bump Interconnect Technology

2014 ◽  
Author(s):  
Gwee Hoon Yen ◽  
Ng Kiong Kay
Keyword(s):  
Sample Preparation ◽  
Failure Analysis ◽  
Flip Chip ◽  
Fault Localization ◽  
Cost Effective ◽  
Fault Isolation ◽  
Voltage Contrast ◽  
Interconnect Technology

Abstract Today, failure analysis involving flip chip [1] with copper pillar bump packaging technologies would be the major challenges faced by analysts. Most often, handling on the chips after destructive chemical decapsulation is extremely critical as there are several failure analysis steps to be continued such as chip level fault localization, chip micro probing for fault isolation, parallel lapping [2, 3, 4] and passive voltage contrast. Therefore, quality of sample preparation is critical. This paper discussed and demonstrated a quick, reliable and cost effective methodology to decapsulate the thin small leadless (TSLP) flip chip package with copper pillar (CuP) bump interconnect technology.

Improving of quality of gate assembly contact surfaces of high-pressure fi ttings by diamond burnishing

2020 ◽  
pp. 99-104
Author(s):  
S.A. Zaydes ◽  
A.N. Mashukov ◽  
T.Ya. Druzhinina
Keyword(s):  
Surface Roughness ◽  
High Pressure ◽  
Main Part ◽  
Conical Surface ◽  
The Real ◽  
Metal Seal ◽  
Diamond Burnishing ◽  
Air Tightness ◽  
Contact Surfaces

The contact belt of the gate assembly is the main part of high pressure fittings. The serviceability of the fittings assembly as whole depends on the air-tightness and quality of the mating surfaces. The technology of diamond burnishing allows to increase the interface of the nodes by red ucing the surface roughness of the metal-to-metal seal. The real experience for improving of the fittings contact belt due to the use of diamond burnishing of the nozzles seats and the conical surface of the rods.

Quality Improvement of the DNA extracted by boiling method in Gram negative bacteria

2017 ◽  
Vol 6 (04) ◽  
pp. 5347 ◽  
Author(s):  
Omar B. Ahmed* ◽  
Anas S. Dablool
Keyword(s):  
Dna Extraction ◽  
Control Method ◽  
Extraction Procedure ◽  
Cost Effective ◽  
High Yield ◽  
Gram Negative Bacteria ◽  
Bacterial Dna ◽  
Gram Negative ◽  
E Coli

Several methods of Deoxyribonucleic acid (DNA) extraction have been applied to extract bacterial DNA. The amount and the quality of the DNA obtained for each one of those methods are variable. The study aimed to evaluate bacterial DNA extraction using conventional boiling method followed by alcohol precipitation. DNA extraction from Gram negative bacilli was extracted and precipitated using boiling method with further precipitation by ethanol. The extraction procedure performed using the boiling method resulted in high DNA yields for both E. coli and K. pneumoniae bacteria in (199.7 and 285.7μg/ml, respectively) which was close to control method (229.3 and 440.3μg/ml). It was concluded that after alcohol precipitation boiling procedure was easy, cost-effective, and applicable for high-yield quality of DNA in Gram-negative bacteria.

scholarly journals End-of-Life Alternatives of Glass Reinforced Polyester Boat Hulls Compared by LCA

2018 ◽  
Vol 27 (4) ◽  
pp. 096369351802700 ◽  
Author(s):  
Mehmet Önal ◽  
Gökdeniz Neşer
Keyword(s):  
End Of Life ◽  
Environmental Impacts ◽  
Raw Materials ◽  
Weight Ratio ◽  
Cost Effective ◽  
Raw Material ◽  
Photochemical Oxidation ◽  
Human Toxicity ◽  
Vacuum Infusion ◽  
Infusion Method

Glass reinforced polyester (GRP), as a thermoset polymer composites, dominates boat building industry with its several advantages such as high strength/weight ratio, cohesiveness, good resistance to environment. However, proper recovering and recycling of GRP boats is became a current environmental requirement that should be met by the related industry. In this study, to propose in a cost effective and environmentally friendly way, Life Cycle Assessment (LCA) has been carried out for six scenarios include two moulding methods (namely Hand Lay-up Method, HLM and Vacuum Infusion Method, VIM) and three End-of-Life (EoL) alternatives(namely Extruding, Incineration and Landfill) for a recreational boat's GRP hulls. A case study from raw materials purchasing phase to disposal/recycling stages has been established taking 11 m length GRP boat hull as the functional unit. Analysis show that in the production phase, the impacts are mainly due to the use of energy (electricity), transport and raw material manufacture. Largest differences between the methods considered (HLM and VIM) can be observed in the factors of marine aquatic ecotoxicity and eutrophication while the closest ones are abiotic depletion, ozon layer depletion and photochemical oxidation. The environmental impact of VIM is much higher than HLM due to its higher energy consumption while vacuum infusion method has lower risk than hand lay-up method in terms of occupational health by using less raw material (resin) in a closed mold. In the comparison of the three EoL techniques, the mechanical way of recycling (granule extruding) shows better environmental impacts except terrestrial ecotoxicity, photochemical oxidation and acidification. Among the EoL alternatives, landfill has the highest environmental impacts except ‘global warming potential’ and ‘human toxicity’ which are the highest in extrusion. The main cause of the impacts of landfill is the transportation needs between the EoL boats and the licenced landfill site. Although it has the higher impact on human toxicity, incineration is the second cleaner alternative of EoL techniques considered in this study. In fact that the similar trend has been observed both in production and EoL phases of the boat. It is obvious that using much more renewable energy mix and greener transportation alternative can reduce the overall impact of the all phases considerably.

scholarly journals Smoothing additive manufactured parts using ns-pulsed laser radiation

2021 ◽  
Author(s):  
Florian Kuisat ◽  
Fernando Lasagni ◽  
Andrés Fabián Lasagni
Keyword(s):  
Surface Roughness ◽  
Mechanical Performance ◽  
State Of The Art ◽  
Pulsed Laser ◽  
Industrial Applications ◽  
Laser Source ◽  
Pulsed Laser Radiation ◽  
Current State ◽  
The Impact

AbstractIt is well known that the surface topography of a part can affect its mechanical performance, which is typical in additive manufacturing. In this context, we report about the surface modification of additive manufactured components made of Titanium 64 (Ti64) and Scalmalloy®, using a pulsed laser, with the aim of reducing their surface roughness. In our experiments, a nanosecond-pulsed infrared laser source with variable pulse durations between 8 and 200 ns was applied. The impact of varying a large number of parameters on the surface quality of the smoothed areas was investigated. The results demonstrated a reduction of surface roughness Sa by more than 80% for Titanium 64 and by 65% for Scalmalloy® samples. This allows to extend the applicability of additive manufactured components beyond the current state of the art and break new ground for the application in various industrial applications such as in aerospace.

scholarly journals Chlorosulfuric acid-assisted production of functional 2D materials

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Mohsen Moazzami Gudarzi ◽  
Maryana Asaad ◽  
Boyang Mao ◽  
Gergo Pinter ◽  
Jianqiang Guo ◽  
...  
Keyword(s):  
Hexagonal Boron Nitride ◽  
2D Materials ◽  
Real Life ◽  
Large Area ◽  
Polar Solvents ◽  
Aspect Ratios ◽  
Two Dimensional Materials ◽  
Liquid Phase Exfoliation

AbstractThe use of two-dimensional materials in bulk functional applications requires the ability to fabricate defect-free 2D sheets with large aspect ratios. Despite huge research efforts, current bulk exfoliation methods require a compromise between the quality of the final flakes and their lateral size, restricting the effectiveness of the product. In this work, we describe an intercalation-assisted exfoliation route, which allows the production of high-quality graphene, hexagonal boron nitride, and molybdenum disulfide 2D sheets with average aspect ratios 30 times larger than that obtained via conventional liquid-phase exfoliation. The combination of chlorosulfuric acid intercalation with in situ pyrene sulfonate functionalisation produces a suspension of thin large-area flakes, which are stable in various polar solvents. The described method is simple and requires no special laboratory conditions. We demonstrate that these suspensions can be used for fabrication of laminates and coatings with electrical properties suitable for a number of real-life applications.

scholarly journals Remote Reflectivity Sensor for Industrial Applications

Sensors ◽  
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.

Sign in / Sign up

Export Citation Format

Share Document