Recent Developments of High-Performance PET Detectors

2017 ◽  
pp. 301-334
Author(s):  
Hao Peng ◽  
Craig S. Levin
Keyword(s):  
High Performance ◽  
Recent Developments ◽  
Pet Detectors

Microstructure of sputter deposited Ni-Sb ohmic contacts on GaAs

1989 ◽  
Vol 47 ◽  
pp. 450-451
Author(s):  
S. Yegnasubramanian ◽  
V.C. Kannan ◽  
R. Dutto ◽  
P.J. Sakach
Keyword(s):  
High Performance ◽  
Ohmic Contacts ◽  
Surface Defects ◽  
Pure Metal ◽  
Device Fabrication ◽  
Native Oxide ◽  
Metal Thin Films ◽  
Recent Developments ◽  
Different Temperatures ◽  
Sputter Deposited

Recent developments in the fabrication of high performance GaAs devices impose crucial requirements of low resistance ohmic contacts with excellent contact properties such as, thermal stability, contact resistivity, contact depth, Schottky barrier height etc. The nature of the interface plays an important role in the stability of the contacts due to problems associated with interdiffusion and compound formation at the interface during device fabrication. Contacts of pure metal thin films on GaAs are not desirable due to the presence of the native oxide and surface defects at the interface. Nickel has been used as a contact metal on GaAs and has been found to be reactive at low temperatures. Formation Of Ni2 GaAs at 200 - 350C is reported and is found to grow epitaxially on (001) and on (111) GaAs, but is shown to be unstable at 450C. This paper reports the investigations carried out to understand the microstructure, nature of the interface and composition of sputter deposited and annealed (at different temperatures) Ni-Sb ohmic contacts on GaAs by TEM. Attempts were made to correlate the electrical properties of the films such as the sheet resistance and contact resistance, with the microstructure. The observations are corroborated by Scanning Auger Microprobe (SAM) investigations.

What Can Digitization Do For Formulated Product Innovation and Development

2020 ◽  
Author(s):  
James McDonagh ◽  
William Swope ◽  
Richard L. Anderson ◽  
Michael Johnston ◽  
David J. Bray
Keyword(s):  
High Performance ◽  
Quality Data ◽  
High Quality Data ◽  
Base Level ◽  
Hybrid Approaches ◽  
Digital Ecosystem ◽  
Recent Developments ◽  
Chemical Simulation ◽  
High Level ◽  
Physical And Chemical

Digitization offers significant opportunities for the formulated product industry to transform the way it works and develop new methods of business. R&D is one area of operation that is challenging to take advantage of these technologies due to its high level of domain specialisation and creativity but the benefits could be significant. Recent developments of base level technologies such as artificial intelligence (AI)/machine learning (ML), robotics and high performance computing (HPC), to name a few, present disruptive and transformative technologies which could offer new insights, discovery methods and enhanced chemical control when combined in a digital ecosystem of connectivity, distributive services and decentralisation. At the fundamental level, research in these technologies has shown that new physical and chemical insights can be gained, which in turn can augment experimental R&D approaches through physics-based chemical simulation, data driven models and hybrid approaches. In all of these cases, high quality data is required to build and validate models in addition to the skills and expertise to exploit such methods. In this article we give an overview of some of the digital technology demonstrators we have developed for formulated product R&D. We discuss the challenges in building and deploying these demonstrators.<br>

Molecular materials for micro-electronics

2000 ◽  
Vol 78 (3) ◽  
pp. 231-241 ◽  
Author(s):  
M D'Iorio
Keyword(s):  
High Performance ◽  
Organic Materials ◽  
Coming Of Age ◽  
Polymeric Materials ◽  
Organic Light Emitting Diodes ◽  
Light Emitting ◽  
Light Emitting Devices ◽  
Plastic Electronics ◽  
Organic Light ◽  
Recent Developments

Molecular organic materials have had an illustrious past but the ability to deposit these as homogeneous thin films has rejuvenated the field and led to organic light-emitting diodes (OLEDs) and the development of an increasing number of high-performance polymers for nonlinear and electronic applications. Whereas the use of organic materials in micro-electronics was restricted to photoresists for patterning purposes, polymeric materials are coming of age as metallic interconnects, flexible substrates, insulators, and semiconductors in all-plastic electronics. The focus of this topical review will be on organic light-emitting devices with a discussion of the most recent developments in electronic devices.PACS Nos.: 85.60Jb, 78.60Fi, 78.55Kz, 78.66Qn, 73.61Ph, 72.80Le

Solar-Driven Sorption Chillers for Residential Space Cooling: A Review of Recent Developments and Possible Applications in Canada

2015 ◽  
Author(s):  
Daniel Bowie ◽  
Cynthia A. Cruickshank
Keyword(s):  
High Performance ◽  
Energy Use ◽  
Peak Load ◽  
Internal Heat ◽  
Electricity Grid ◽  
Residential Sector ◽  
Absorption Chillers ◽  
Space Cooling ◽  
Recent Developments ◽  
Advanced Cycles

Energy use for space cooling has increased by 156% from 1990 to 2010 in the Canadian residential sector. In many parts of the country, the increasing use of electrically driven air-conditioners has begun to shift the peak load on the electricity grid from the coldest days of winter to the hottest days of summer. Many of Canada’s major electric utilities providers rely on fossil fuels to generate the additional capacity needed to meet the peak demand, resulting in significant greenhouse gas emissions. Solar-driven sorption chillers remain one of the possible solutions for shaving the peak loads experienced by the electricity grid. This paper presents a review of the recent developments in the research of adsorption and absorption chillers, as well as a comparison of the two technologies based on the latest published experimental results found in the literature. Adsorption chillers continue to evolve in their design, including the use of new consolidated and composite adsorbents, the integration of coated adsorbers into internal heat exchangers, and newly developed advanced cycles for heat and mass recovery. While the physical design of adsorption chillers continues to be advanced, the development of absorption chillers for solar cooling applications has largely been focused on optimizing the system as a whole through improved control strategies and the implementation of newly developed high performance solar collectors. Finally, the paper aims to assess the current state of development of solar-driven sorption chillers to provide insight into their applicability in the Canadian residential sector, as well as the remaining challenges facing this technology.

scholarly journals Towards Damage Controlled Hot Forming

2018 ◽  
Vol 885 ◽  
pp. 56-63
Author(s):  
Markus Bambach ◽  
Irina Sizova ◽  
Aliakbar Emdadi
Keyword(s):  
Metal Forming ◽  
High Performance ◽  
Titanium Aluminides ◽  
Turbine Blades ◽  
Process Time ◽  
Jet Engines ◽  
Internal Damage ◽  
Creep Properties ◽  
Recent Developments ◽  
Ram Speed

Metal forming processes may induce internal damage in the form of voids in the workpiece under unfavorable deformation conditions. Controlling the amount of damage induced by metal forming operations may increase service performance of the produced parts. Damage is crucial in high-performance components of limited workability such as jet engine turbine blades. Recent developments have introduced forged titanium aluminides into commercial jet engines. Titanium aluminides are lightweight intermetallic compounds with excellent creep properties but very limited ductility. Their low workability requires isothermal forging at slow strain rates, which is typically kept constant in the process. This work explores the possibility of increasing the ram speed during the process so that the process time is reduced while the amount of damage introduced into the workpiece is controlled. The results show that a 25% reduction in process time seems viable without increase in damage by solving an optimal control problem, in which the ram speed profile is determined off-line by minimization.

scholarly journals Tribology of 2D Nanomaterials: A Review

2020 ◽  
Author(s):  
Paul С. Uzoma ◽  
Huan Hu ◽  
Mahdi Khadem ◽  
Oleksiy V. Penkov
Keyword(s):  
High Performance ◽  
2D Materials ◽  
Chemical Properties ◽  
Solid Lubricants ◽  
Friction Behavior ◽  
Comprehensive Overview ◽  
Wear Rates ◽  
Recent Developments ◽  
Frictional Coefficients ◽  
Physical And Chemical

The exfoliation of graphene has opened a new frontier in material science with a focus on 2D materials. The unique thermal, physical and chemical properties of these materials have made them one of the choicest candidates in novel mechanical and nano-electronic devices. Notably, 2D materials such as graphene, MoS2, WS2, h-BN, and Black Phosphorus have shown outstanding lowest frictional coefficients and wear rates, making them attractive materials for high-performance nano-lubricants and lubricating applications. The objective of this work is to provide a comprehensive overview of the most recent developments in the tribological potentials of 2D materials. At first, the essential physical, wear, and frictional characteristics of the 2D materials including their production techniques are discussed. Subsequently, the experimental explorations and theoretical simulations of the most common 2D materials are reviewed in regards to their tribological applications such as their use as solid lubricants and surface lubricant nano-additives. The effects of micro/nano textures on friction behavior are also reviewed. Finally, the current challenges in tribological applications of 2D materials and their prospects are discussed.

scholarly journals Microwave Liquid Crystal Technology

Crystals ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 355 ◽  
Author(s):  
Holger Maune ◽  
Matthias Jost ◽  
Roland Reese ◽  
Ersin Polat ◽  
Matthias Nickel ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Millimeter Wave ◽  
Antenna Arrays ◽  
High Performance ◽  
Beam Steering ◽  
Phase Shifters ◽  
Dielectric Waveguides ◽  
Microwave Components ◽  
Recent Developments ◽  
Rectangular Waveguides

Tunable Liquid Crystal (LC)-based microwave components are of increasing interest in academia and industry. Based on these components, numerous applications can be targeted such as tunable microwave filters and beam-steering antenna systems. With the commercialization of first LC-steered antennas for Ku-band e.g., by Kymeta and Alcan Systems, LC-based microwave components left early research stages behind. With the introduction of terrestrial 5G communications systems, moving to millimeter-wave communication, these systems can benefit from the unique properties of LC in terms of material quality. In this paper, we show recent developments in millimeter wave phase shifters for antenna arrays. The limits of classical high-performance metallic rectangular waveguides are clearly identified. A new implementation with dielectric waveguides is presented and compared to classic approaches.

New Developments in the Plasma Transferred Arc Process

1997 ◽  
Author(s):  
R.J. DuMola ◽  
G.R. Heath
Keyword(s):  
High Performance ◽  
Power Utility ◽  
Small Areas ◽  
Powder Alloys ◽  
Plasma Transferred Arc ◽  
Transferred Arc ◽  
Recent Developments ◽  
Coating Method ◽  
And Performance ◽  
New Applications

Abstract The plasma transferred arc process continues to be the coating method of choice for the application of cobalt base alloys onto valve and valve trim. Although new applications have been developed over the years, the process remains largely associated with the application of high performance, highly alloyed powders for relatively small parts or small areas of large parts. The use of the plasma transferred arc process for large volume application has been limited by the robustness and performance characteristics of the equipment and the use of cobalt. A new plasma transferred arc system (power source, torch and process controller) has been developed which allows the application of powder metal alloys at deposition rates of up to 40 pounds per hour. In addition, there has been a development of new non-cobalt powder alloys with excellent mixed corrosion and wear resistance properties. These capabilities have rendered the process technically and economically viable for large and demanding applications in the mining, power utility and steel industries. The new PTA system and the recent developments in powder alloys will be discussed. Reference will be made to specific applications in target industries.

Sign in / Sign up

Export Citation Format

Share Document