Improved Performance of High Energy Materials Based on Dinitramide Salts and Its Liquid Monopropellant

2021 ◽  
Vol 21 (8) ◽  
pp. 4524-4531
Author(s):  
Wooram Kim ◽  
Sujeong Heo ◽  
Jong-Ki Jeon ◽  
Youngmin Jo
Keyword(s):  
High Purity ◽  
Liquid Fuel ◽  
Room Temperature ◽  
Specific Impulse ◽  
Catalytic Decomposition ◽  
High Energy ◽  
Energy Materials ◽  
Practical Applications ◽  
Dinitramide Salts ◽  
Improved Performance

As an eco-friendly alternative fuel material, ammonium dinitramide (ADN, NH4N(NO2)2) is safe and stable at room temperature; however, it requires high purity for practical applications. A small amount of impurities can retard the catalytic decomposition of the monopropellant in the thruster, lower the specific impulse, and induce side effects such as clogging of the nozzle. Therefore, we purified NH4N(NO2)2 by performing repeated extractions, adsorption by powdered activated carbon, and low-temperature extractions. In this study, we evaluated the chemical density of purified NH4N(NO2)2 through Fourier-transform infrared spectroscopy, ultraviolet-visible spectroscopy, and ion chromatography, and obtained a final purity of 99.8%. Furthermore, we fabricated a liquid fuel using high-purity NH4N(NO2)2 as the main oxidizing agent, and can be prepared a mono-propellant formulation that exhibited decomposition at a minimum temperature of 148 °C.

EFFECT OF BORON ON THE COMBUSTION CHARACTERISTICS OF METALLIZED HIGH-ENERGY MATERIALS

2020 ◽  
Author(s):  
A. Korotkikh ◽  
◽  
I. Sorokin ◽  
◽  
Keyword(s):  
Specific Impulse ◽  
Equilibrium Composition ◽  
Combustion Products ◽  
High Energy ◽  
Combustion Characteristics ◽  
Solid Propellants ◽  
Energy Materials ◽  
High Energy Materials ◽  
Condensed Combustion Products ◽  
Active Fuel Binder

The paper presents the results of thermodynamic calculations of the effect of pure boron additives on combustion characteristics of high-energy materials (HEM) based on ammonium perchlorate, ammonium nitrate, active fuel-binder, and powders of aluminum Al, titanium Ti, magnesium Mg, and boron B. The combustion parameters and the equilibrium composition of condensed combustion products (CCPs) of HEM model compositions were obtained with thermodynamic calculation program “Terra.” The compositions of solid propellants with different ratios of metals (Al/B, Ti/B, Mg/B, and Al/Mg/B) were considered. The combustion temperature Tad in a combustion chamber, the vacuum specific impulse J at the nozzle exit, and the mass fraction ma of the CCPs for HEMs were determined.

Near Infrared Photoluminescence of NCVSi- Centers in High-Purity Semi-Insulating 4H-SiC Irradiated with Energetic Charged Particles

2020 ◽  
Vol 1004 ◽  
pp. 355-360
Author(s):  
Shin Ichiro Sato ◽  
Takuma Narahara ◽  
Shinobu Onoda ◽  
Yuichi Yamazaki ◽  
Yasuto Hijikata ◽  
...  
Keyword(s):  
High Purity ◽  
Room Temperature ◽  
Near Infrared ◽  
Ion Beam ◽  
High Energy ◽  
Implantation Dose ◽  
Implantation Technique ◽  
Photoluminescence Intensity ◽  
Wide Range ◽  
Excitation Laser

This paper reports optical propertites of negatively charged NCVSi- centers in silicon carbide (a nitrogen substituting for a carbon atom adjacent to a silicon vacancy) whose emission wavlength is 1100-1500 nm at room temperature. High-purity semi-insulating (HPSI) 4H-SiCs are implanted with high energy N ion beams and subsequently thermally annealed to form NCVSi centers. We investigated a wide range of N ion implantation dose using a micro ion beam implantation technique and observed the photoluminescence intensity from the SiC-NV centers. We show that under conditions of heavy implantation, the excitation laser power excites residual defects and their fluorescences intereferes with the emission from the NCVSi- centers. These results allow us to clarify the requirements to optically detect isolated single NCVSi- centers at lightly implanted conditions.

Innovative Solid Rocket Propellant Formulations for Space Propulsion

2018 ◽  
pp. 1-24 ◽  
Author(s):  
Luigi T. DeLuca ◽  
Manfred A. Bohn ◽  
Volker Gettwert ◽  
Volker Weiser ◽  
Claudio Tagliabue
Keyword(s):  
Short Range ◽  
Negative Impact ◽  
Specific Impulse ◽  
High Energy ◽  
Space Propulsion ◽  
Energy Materials ◽  
Rocket Propulsion ◽  
Dual Metal ◽  
To Come ◽  
Solid Rocket

Solid rocket propulsion enjoys unique properties favoring its use in space exploration and military missions still for decades to come. Yet, it also suffers a limited performance especially in terms of gravimetric specific impulse. Although new high-energy materials have been identified, most of them are far from being practically usable in the short range. Presently, no integrated vehicle designs make use of these new ingredients. A broad overview is discussed in this paper and attention is paid to Ammonium Dinitramide, ADN to overcome the current limitations of Ammonium Perchlorate, AP. The latter imply not only a limited gravimetric specific impulse but also a negative impact on the environment and personal health. ADN-based dual-oxidizer formulations, with Al-based dual-metal fuels and inert or energetic binders, are promising solutions for a variety of solid rocket propulsion missions aiming respectively at minimizing environmental impact (ADN + AN) or maximizing performance (ADN + AP).

scholarly journals Features of thermal behavior and ignition of HEM with bimetal powders

2018 ◽  
Vol 194 ◽  
pp. 01029
Author(s):  
Alexander Korotkikh ◽  
Ivan Sorokin ◽  
Ekaterina Selikhova
Keyword(s):  
Thermal Behavior ◽  
Ignition Time ◽  
Specific Impulse ◽  
Burning Surface ◽  
High Energy ◽  
Combustion Characteristic ◽  
Butadiene Rubber ◽  
Energy Materials ◽  
Recoil Force ◽  
Gasification Products

The use of metal fuel in high-energy materials (HEM) for propulsion is the most energy efficient method allows to the combustion characteristic increase for solid propellants and specific impulse. Aluminum powder is used in original HEM. To improve the ignition characteristics of HEM advisable to use the catalyst (nonmetals, metals or their oxides). Paper presents the experimental data of the thermal behavior and ignition for HEM based on AP and butadiene rubber, containing bimetal powders: aluminum/iron and aluminum/boron. The use of Alex/Fe powder in HEM decreases the ignition time by 1.3–1.9 times under initiation by CO2 laser in air at the range of heat flux density of 55–220 W/cm2 and increases of the recoil force of gasification products outflow from burning surface by 27 % during combustion of propellant due to possible of the catalytic effect, which reduces the beginning temperature of AP high-temperature decomposition by ~20 °C, and interaction of thermite mixture of aluminum and iron particles in the reaction layer of propellant. Then the use of Alex/B in HEM the ignition time is decreased by 1.2–1.4 times, the recoil force of gasification products outflow from burning surface is slightly increased by 9 %.

Operating Characteristics of a Small Cryogenic Stirling Engine With a Displacer

2011 ◽  
Author(s):  
Toshio Otaka ◽  
Masaru Ito
Keyword(s):  
Low Temperature ◽  
Heat Source ◽  
Heat Sink ◽  
Room Temperature ◽  
Electrical Energy ◽  
High Energy ◽  
Operating Characteristics ◽  
Practical Applications ◽  
Heat Engines ◽  
Temperature Ranges

The green house effect by carbon dioxide issue would make better recognizing the importance of efficient use of energy in terms of high energy conservation measures. Accordingly, attention is drawn to the Stirling cycle machine, which is a perfect Freon free and efficient machine. Most Stirling engines operate in temperature ranges in which the temperature difference between the heat source and heat sink is between 100 K and 700 K, with the room temperature being at the lower end of the operating temperature range. However, information available on engines that utilize the room temperature as the heat source and the ultra-low temperature of liquid nitrogen as the heat sink is scarce. Engines that operate within such temperature ranges are called cryogenic heat engines. If their practical applications are realized, energy that has hitherto been wasted during the use of ultra-low-temperature media can be recovered in the form of electrical energy. We have designed and developed a 500 W class Stirling machine as a cryogenic engine. This paper presents some operating characteristics.

scholarly journals Advances in Hypergolic Propellants: Ignition, Hydrazine, and Hydrogen Peroxide Research

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Stephen M. Davis ◽  
Nadir Yilmaz
Keyword(s):  
Hydrogen Peroxide ◽  
Wide Temperature Range ◽  
High Purity ◽  
Room Temperature ◽  
Specific Impulse ◽  
Review Of The Literature ◽  
Low Toxicity ◽  
Large Effort ◽  
Hypergolic Propellants ◽  
High Purity Hydrogen

A review of the literature pertaining to hypergolic fuel systems, particularly using hydrazine or its derivatives and hydrogen peroxide, has been conducted. It has been shown that a large effort has been made towards minimizing the risks involved with the use of a toxic propellant such as the hydrazine. Substitution of hydrazines for nontoxic propellant formulations such as the use of high purity hydrogen peroxide with various types of fuels is one of the major areas of study for future hypergolic propellants. A series of criteria for future hypergolic propellants has been recommended, including low toxicity, wide temperature range applicability, short ignition delay, high specific impulse or density specific impulse, and storability at room temperature.

scholarly journals Improving the alkali metal electrode/inorganic solid electrolyte contact via room-temperature ultrasound solid welding

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Xinxin Wang ◽  
Jingjing Chen ◽  
Dajian Wang ◽  
Zhiyong Mao
Keyword(s):  
Alkali Metal ◽  
Solid Electrolyte ◽  
Current Density ◽  
Room Temperature ◽  
Metal Electrode ◽  
High Energy ◽  
Ultrasonic Welding ◽  
Rechargeable Batteries ◽  
Interfacial Resistance ◽  
Practical Applications

AbstractThe combination of alkali metal electrodes and solid-state electrolytes is considered a promising strategy to develop high-energy rechargeable batteries. However, the practical applications of these two components are hindered by the large interfacial resistance and growth of detrimental alkali metal depositions (e.g., dendrites) during cycling originated by the unsatisfactory electrode/solid electrolyte contact. To tackle these issues, we propose a room temperature ultrasound solid welding strategy to improve the contact between Na metal and Na3Zr2Si2PO12 (NZSP) inorganic solid electrolyte. Symmetrical Na|NZSP | Na cells assembled via ultrasonic welding show stable Na plating/stripping behavior at a current density of 0.2 mA cm−2 and a higher critical current density (i.e., 0.6 mA cm−2) and lower interfacial impedance than the symmetric cells assembled without the ultrasonic welding strategy. The beneficial effect of the ultrasound welding is also demonstrated in Na|NZSP | Na3V2(PO4)3 full coin cell configuration where 900 cycles at 0.1 mA cm−2 with a capacity retention of almost 90% can be achieved at room temperature.

Characterization of intergranular cuprous oxide in polycrystalline YBa2Cu3O7-x

1988 ◽  
Vol 46 ◽  
pp. 880-881
Author(s):  
Bradley L. Thiel ◽  
Chan Han R. P. ◽  
Kurosky L. C. Hutter ◽  
I. A. Aksay ◽  
Mehmet Sarikaya
Keyword(s):  
Grain Boundary ◽  
Cuprous Oxide ◽  
Room Temperature ◽  
Boundary Phase ◽  
Spectroscopic Techniques ◽  
Transition Width ◽  
Practical Applications ◽  
Thin Foils ◽  
Superconducting Oxides

The identification of extraneous phases is important in understanding of high Tc superconducting oxides. The spectroscopic techniques commonly used in determining the origin of superconductivity (such as RAMAN, XPS, AES, and EXAFS) are surface-sensitive. Hence a grain boundary phase several nanometers thick could produce irrelevant spectroscopic results and cause erroneous conclusions. The intergranular phases present a major technological consideration for practical applications. In this communication we report the identification of a Cu2O grain boundary phase which forms during the sintering of YBa2Cu3O7-x (1:2:3 compound).Samples are prepared using a mixture of Y2O3. CuO, and BaO2 powders dispersed in ethanol for complete mixing. The pellets pressed at 20,000 psi are heated to 950°C at a rate of 5°C per min, held for 1 hr, and cooled at 1°C per min to room temperature. The samples show a Tc of 91K with a transition width of 2K. In order to prevent damage, a low temperature stage is used in milling to prepare thin foils which are then observed, using a liquid nitrogen holder, in a Philips 430T at 300 kV.

High-purity Ge x-ray detectors: Sensitivity factors and usefulness

1990 ◽  
Vol 48 (2) ◽  
pp. 548-548
Author(s):  
E. B. Steel
Keyword(s):  
High Purity ◽  
High Energy ◽  
Quantitative Chemical Analysis ◽  
Detector Performance ◽  
X Ray ◽  
Detector Sensitivity ◽  
Specimen Holder ◽  
Many Instruments ◽  
Charge Resolution ◽  
Sensitivity Factors

High Purity Germanium (HPGe) x-ray detectors are now commercially available for the analytical electron microscope (AEM). The detectors have superior efficiency at high x-ray energies and superior resolution compared to traditional lithium-drifted silicon [Si(Li)] detectors. However, just as for the Si(Li), the use of the HPGe detectors requires the determination of sensitivity factors for the quantitative chemical analysis of specimens in the AEM. Detector performance, including incomplete charge, resolution, and durability has been compared to a first generation detector. Sensitivity factors for many elements with atomic numbers 10 through 92 have been determined at 100, 200, and 300 keV. This data is compared to Si(Li) detector sensitivity factors.The overall sensitivity and utility of high energy K-lines are reviewed and discussed. Many instruments have one or more high energy K-line backgrounds that will affect specific analytes. One detector-instrument-specimen holder combination had a consistent Pb K-line background while another had a W K-line background.

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