scholarly journals An investigation into sealing materials for vacuum glazing

2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Paul Onyegbule ◽  
◽  
Harjit Singh ◽  
Keyword(s):  
Renewable Energy ◽  
High Performance ◽  
Glass Powder ◽  
Thermal Insulator ◽  
Sealing Material ◽  
Different Temperatures ◽  
Vacuum Glazing ◽  
The Impact ◽  
Sealing Materials ◽  
Lower Melting Temperature

Vacuum glazing is an innovative transparent thermal insulator that has application in high performance window, especially in renewable energy. Different materials as well as sealing methods have been adopted to seal windows with different temperatures. The impact of temperatures on sealing layers has been found to have significant effects on the microstructure of the seal. This paper seeks to investigate the effects of sealing materials specifically glass powder and flux compound (borax) for vacuum glazing. The findings of the experiment conducted show that the sealing material was rigid with some leakage around the edge, and we found that this could be stopped by enhancing the uniformity of the seal within the periphery. Also, we found that due to the intense tensile stress from the oven surface temperature of the seal at 200 °C, a crack was observed at the side of the glass. Based on the above findings, this study concludes that a glass powder with a lower melting temperature of below 250 °C with the addition of an adhesive (borax flux) should be used for future vacuum seals.

scholarly journals Mechanical Properties of Powder Metallugry (Ti-6Al-4V) with Hot Isostatic Pressing

2020 ◽  
Vol 10 (3) ◽  
pp. 5637-5642
Author(s):  
M. A. Elfghi ◽  
M. Gunay
Keyword(s):  
Mechanical Properties ◽  
Titanium Alloys ◽  
Performance Optimization ◽  
High Performance ◽  
Hot Isostatic Pressing ◽  
Two Phase ◽  
Manufacturing Defects ◽  
Isostatic Pressing ◽  
Different Temperatures ◽  
The Impact

Titanium alloys are widely used due to their high performance and low density in comparison with iron-based alloys. Their applications extend to aerospace and military in order to utilize their high resistance for corrosion. Understanding the mechanical properties and microstructure of titanium alloys is critical for performance optimization, as well as their implications on strength, plasticity, and fatigue. Ti-6Al-4V is an α+β two-phase alloy and is considered one of the most commonly used titanium alloys for weight reduction and high-performance. To avoid manufacturing defects, such as porosity and composition segregation, Hot Isostatic Pressing (HIP) is used to consolidate alloy powder. The HIP method is also used to facilitate the manufacturing of complex structures that cannot be made with forging and casting. In the current research, Ti-6Al-4V alloys were manufactured with HIP and the impact on heat treatment under different temperatures and sintering durations on the performance and microstructure of the alloy was studied. The results show changes in mechanical properties and microstructure with the increase of temperature and duration.

The Microstructure Properties of PbO-TiO2-SiO2 System Sealing Solder for Vacuum Glazing

2016 ◽  
Vol 693 ◽  
pp. 644-652
Author(s):  
Xiang Shan ◽  
Hong Miao ◽  
Jian Feng Zhang ◽  
Hong Jun Wang ◽  
Juan Sun
Keyword(s):  
Transition Layer ◽  
Glass Substrate ◽  
Soda Lime ◽  
Soda Lime Glass ◽  
Soda Lime Glass Substrate ◽  
Sealing Material ◽  
Different Temperatures ◽  
Tight Connection ◽  
Vacuum Glazing ◽  
Sealing Glass

Microstructure properties of PbO-TiO2-SiO2 system sealing solder for vacuum glazing was studied. Sealing solder was placed on the sealing glass substrate. Samples were obtained by sintering at different temperatures. The microstructure properties and binding properties with soda lime glass substrate at different temperatures was observed and studied. Micro hardness of the sealing solder after sintering were tested. The results show that in the solder sealing temperature, a transition layer was formed gradually between the sealing solder and the glass substrate as the sintering temperature increases. PbO and SiO2are main ingredients of the transition layer. This layer performed tight connection with the glass substrate after it was completely formed. The interface between sealing solder and soda lime glass substrate showed good performance. PbO-TiO2-SiO2-RxOy system is an ideal sealing material for the production of vacuum glazing.

Review on Power Electronics Circuits in Renewable Energy Systems

2017 ◽  
Vol 3 (7) ◽  
Author(s):  
Aakash Shukla ◽  
Dr Anula Khare
Keyword(s):  
Renewable Energy ◽  
Power Electronics ◽  
High Performance ◽  
Renewable Energy Sources ◽  
Energy Systems ◽  
Qualitative Description ◽  
Energy Sources ◽  
Smart Energy Management ◽  
Energy Conversion Systems ◽  
The Impact

The rapid increase in global energy consumption and the impact of greenhouse gas emissions has accelerated the transition towards greener energy sources. The need for distributed generation (DG) employing renewable energy sources such as wind, solar and fuel cells has gained significant momentum. Advanced power electronic systems, affordable high performance devices, and smart energy management principles are deemed to be an integral part of renewable, green and efficient energy systems. This paper briefly describes the attributes of DG. An overview of wind, fuel cell, solar based energy conversion systems has been presented. A qualitative description of the role of power electronics in wind, solar, and photovoltaic systems has been presented.

scholarly journals Fluidity Influencing Factors Analysis and Ratio Optimization of New Sealing Materials Based on Response Surface Method

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Xin Guo ◽  
Sheng Xue ◽  
Yaobin Li ◽  
Chunshan Zheng ◽  
Gege Yang
Keyword(s):  
Compressive Strength ◽  
Setting Time ◽  
Expansion Rate ◽  
Key Factors ◽  
Gas Drainage ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Sealing Material ◽  
The Impact ◽  
Sealing Materials

The borehole sealing material is one of the key factors affecting the gas drainage effect of a borehole. This paper takes the compressive strength, fluidity, expansion rate, and setting time of the sealing material as the main research indicators and explores the influence of each key influencing factor on the performance of the high-fluid sealing material through the single factor experiment method. Using the Design-Expert 8.0.5 Trial software designed orthogonal experiments and establishing a quadratic model between liquidity and each test factor, which showed the impact of each key factor on the fluidity. Finally, by adjusting the amount of admixtures, the optimal ratio of high-fluidity borehole sealing materials was obtained. The results showed that the key factors had the following order of significance: water – cement   reducing   agent > water – cement   ratio > retarder > expansion   agent . With the water-cement ratio and the amount of water reducing agent increase, the fluidity of the material will increase; and with the increase of the retarder and expansion agent, the fluidity will decrease. In actual use, the fluidity is the main factor, but the expansion rate, compressive strength, and setting time are also considered. The optimal percentages were found for the high-fluidity borehole sealing material: a water-cement ratio of 1, along with 0.03% retarder, 0.5% water reducer, and 8% expansion agent. These research results could provide a reference for improving the performance of gas drainage borehole sealing materials and enhancing the effect of gas drainage.

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.

Dietary Vitamin and Stability of Oral Anticoagulation: Proposal of a Diet with Constant Vitamin K1 Content

1997 ◽  
Vol 77 (03) ◽  
pp. 504-509 ◽  
Author(s):  
Sarah L Booth ◽  
Jacqueline M Charnley ◽  
James A Sadowski ◽  
Edward Saltzman ◽  
Edwin G Bovill ◽  
...  
Keyword(s):  
Dietary Intake ◽  
Vitamin K ◽  
High Performance ◽  
Case Reports ◽  
Food Composition ◽  
Dietary Guidelines ◽  
Dietary Vitamin ◽  
Vitamin K1 ◽  
The Stability ◽  
The Impact

SummaryCase reports cited in Medline or Biological Abstracts (1966-1996) were reviewed to evaluate the impact of vitamin K1 dietary intake on the stability of anticoagulant control in patients using coumarin derivatives. Reported nutrient-drug interactions cannot always be explained by the vitamin K1 content of the food items. However, metabolic data indicate that a consistent dietary intake of vitamin K is important to attain a daily equilibrium in vitamin K status. We report a diet that provides a stable intake of vitamin K1, equivalent to the current U.S. Recommended Dietary Allowance, using food composition data derived from high-performance liquid chromatography. Inconsistencies in the published literature indicate that prospective clinical studies should be undertaken to clarify the putative dietary vitamin K1-coumarin interaction. The dietary guidelines reported here may be used in such studies.

Overcoming stereotypes of renewable energy

2019 ◽  
pp. 124-136
Author(s):  
Victor D. Gazman
Keyword(s):  
Renewable Energy ◽  
Empirical Analysis ◽  
Energy Generation ◽  
New Paradigm ◽  
Financial Instrument ◽  
Promising Direction ◽  
Investment Projects ◽  
Power Stations ◽  
New Generation ◽  
The Impact

The article considers prerequisites for the formation of a new paradigm in the energy sector. The factors that may affect the imminent change of leadership among the energy generation are analyzed. The variability of the projects of creation and functioning of power stations is examined. The focus is made on problematic aspects of the new generation, especially, storage and supply of energy, achieving a system of parity that ensures balance in pricing generations. The author substantiates the principles of forming system of parities arising when comparing traditional and new generations. The article presents the results of an empirical analysis of the 215 projects for the construction of facilities for renewable energy. The significance and direction of the impact of these factors on the growth in investment volumes of transactions are determined. The author considers leasing as an effective financial instrument for overcoming stereotypes of renewable energy and as a promising direction for accelerated implementation of investment projects.

Static and Dynamic Studies of Gasoline in View of its Octane Number and its Toxic Effect

2013 ◽  
Vol 12 (7) ◽  
pp. 451-459
Author(s):  
Ashraf Yehia El-Naggar ◽  
Mohamed A. Ebiad
Keyword(s):  
Toxic Effect ◽  
Aromatic Hydrocarbons ◽  
Octane Number ◽  
Liquid Fuel ◽  
Positive Impact ◽  
Hydrocarbon Composition ◽  
Different Temperatures ◽  
Different Seasons ◽  
The One ◽  
The Impact

Gasoline come primarily from petroleum cuts, it is the preferred liquid fuel in our lives. Two gasoline samples of octane numbers 91 and 95 from Saudi Arabia petrol stations were studied. This study was achieved at three different temperatures 20oC, 30oC and 50oC representing the change in temperatures of the different seasons of the year. Both the evaporated gases of light aromatic hydrocarbons (BTEX) of gasoline samples inside the tank were subjected to analyze qualitatively and quantitatively via capillary gas chromatography. The detailed hydrocarbon composition and the octane number of the studied gasoline samples were determined using detailed hydrocarbon analyzer. The idea of research is indicating the impact of light aromatic compounds in gasoline on the toxic effect of human and environment on the one hand, and on octane number of gasoline on the other hand. Although the value of octane number will be reduced but this will have a positive impact on the environment as a way to produce clean fuel.

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