Artykuły w czasopismach: „Hydrazine propellants”

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Davis, Stephen M., i Nadir Yilmaz. "Advances in Hypergolic Propellants: Ignition, Hydrazine, and Hydrogen Peroxide Research". Advances in Aerospace Engineering 2014 (15.09.2014): 1–9. http://dx.doi.org/10.1155/2014/729313.

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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.

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Mayer, Alfons, i Wolter Wieling. "Green Propulsion Research at TNO the Netherlands". Transactions on Aerospace Research 2018, nr 4 (1.12.2018): 1–24. http://dx.doi.org/10.2478/tar-2018-0026.

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Abstract This paper describes the recent theoretical and experimental research by the Netherlands Organisation for Applied Scientific Research (TNO) into green replacements for hydrazine, hydrazine derivatives and nitrogen tetroxide, as propellants for in-space propulsion. The goal of the study was to identify propellants that are capable of outperforming the current propellants for space propulsion and are significantly less hazardous for humans and the environment. Two types of propellants were investigated, being monopropellants and bipropellants. The first section of the paper discusses the propellant selection. Nitromethane was found to be the most promising monopropellant. As bipropellant, a combination of hydrogen peroxide (HP) and ethanol was selected, where the ethanol is rendered hypergolic with hydrogen peroxide. The second part of the paper describes the experimental verification of these propellants by means of engine testing. Initiation of the decomposition of nitromethane was found to be problematic, hypergolic ignition of the hydrogen peroxide and ethanol bipropellant however was successfully demonstrated.

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Remissa, I., H. Jabri, Y. Hairch, K. Toshtay, M. Atamanov, S. Azat i R. Amrousse. "Propulsion Systems, Propellants, Green Propulsion Subsystems and their Applications: A Review". Eurasian Chemico-Technological Journal 25, nr 1 (20.03.2023): 3–19. http://dx.doi.org/10.18321/ectj1491.

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A wide range of propellants, and propulsion systems in space exploration by aircrafts or space vehicles was studied, developed, investigated, and commercialized. Liquid, solid, or hybrid propellants have been used for rocket’s launches. In this review, a consistent definition of space propulsion systems, including solid, liquid and hybrid has been given with up-to-date state of developments. A comparison of their performances was made by theoretical and experimental specific impulses. On the other hand, ammonium perchlorate and hydrazine were used as propellants for rocket’s launches and for satellite’s maneuverings; respectively. However, their high toxicity and their storage problem pushed researchers and scientists to investigate and develop other eco-friendly, propellant systems, so called “green propellants”, for launch or reaction control systems of satellites.

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Davis, Stephen M., i Nadir Yilmaz. "Thermochemical Analysis of Hypergolic Propellants Based on Triethylaluminum/Nitrous Oxide". International Journal of Aerospace Engineering 2014 (2014): 1–5. http://dx.doi.org/10.1155/2014/269836.

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The vacuum specific impulse, density vacuum specific impulse, and solid exhaust products were examined for several propellant formulations based on the pyrophoric material triethylaluminum (TEA) using CEA thermodynamics code. Evaluation of TEA neat and mixed with hydrocarbon fuels with LOX, N2O, N2O4, liquefied air, and HNO3were performed at stoichiometry. The vacuum specific impulse of neat TEA with N2O is comparable to that of nitric acid with the same, but the N2O formulation will produce slightly less solid products during combustion. Additionally, N2O-TEA propellants have vacuum specific impulses and density vacuum specific impulses within 92.9% and 86.7% of traditional hydrazine propellant formulations under stoichiometric conditions.

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Tejeda, Jesús Manuel Muñoz, A. Schwertheim i A. Knoll. "WATER AS AN ENVIRONMENTALLY FRIENDLY PROPELLANT FOR A MULTI-FUNCTIONAL SPACECRAFT ARCHITECTURE". International Journal of Energetic Materials and Chemical Propulsion 22, nr 2 (2023): 21–33. http://dx.doi.org/10.1615/intjenergeticmaterialschemprop.v22.i2.20.

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Water can be utilized as spacecraft propellant to dramatically reduce the environmental impact of constructing and operating a satellite. In this work, a multi-mode chemical-electrical propulsion system, in which water was used as the propellant in both high thrust chemical and high specific impulse electrical maneuvres, was studied. This type of system allows the spacecraft architecture community to divest from traditional propellants such as hydrazine and xenon, thus reducing the production of highly toxic chemicals and dramatically reducing the carbon footprint of propulsion systems. Water has the lowest toxicity, carbon footprint, and price of any current or proposed propellant, and has been shown in laboratory testing to be a feasible alternative compared to traditionally used propellants. The unique role it can play across multiple spacecraft subsystems suggests that the commercial adoption of water as a propellant will reduce cost and mass while also reducing the environmental impact of the satellites of tomorrow. This technology has the ability to enable the development of modular, multifunctional, competitive, and environmentally friendly spacecraft architectures.

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Timoshenko, V. I., L. K. Patryliak, Yu V. Knyshenko, V. M. Durachenko i A. S. Dolinkevych. "Use of a “green” propellant in low-thrust control jet engine systems". Technical mechanics 2021, nr 4 (7.12.2021): 29–43. http://dx.doi.org/10.15407/itm2021.04.029.

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The aim of this work is to analyze the state of the art in the development and use of pollution-free (“green”) propellants in low-thrust jet engines used as actuators of spacecraft stabilization and flight control systems and to adapt computational methods to the determination of “green”-propellant engine thrust characteristics. The monopropellant that is now widely used in the above-mentioned engines is hydrazine, whose decomposition produces a jet thrust due to the gaseous reaction products flowing out of a supersonic nozzle. Because of the high toxicity of hydrazine and the complex technology of hydrazine filling, it is important to search for its less toxic substitutes that would compare well with it in energy and mass characteristics. A promising line of this substitution is the use of ion liquids classed with “green” ones. The main components of these propellants are a water solution of an ion liquid and a fuel component. The exothermic thermocatalytic decomposition of a “green” propellant is combined with the combustion of its fuel component and increases the combustion chamber pressure due to the formation of gaseous products, which produces an engine thrust. It is well known that a “green” propellant itself and the products of its decomposition and combustion are far less toxic that hydrazine and the products of its decomposition, The paper presents data on foreign developments of “green” propellants of different types, which are under test in ground (bench) conditions and on a number of spacecraft. The key parameter that governs the efficiency of the jet propulsion system thrust characteristics is the performance of the decomposition and combustion products, which depends on their temperature and chemical composition. The use of equilibrium high-temperature process calculation methods for this purpose is too idealized and calls for experimental verification. Besides, a substantial contribution to the end effect is made by the design features of propellant feed and flow through a fine-dispersed catalyst layer aimed at maximizing the monopropellant-catalyst contact area. As a result, in addition to the computational determination of the thrust characteristics of a propulsion system under design, its experimental tryout is mandatory. The literature gives information on the performance data of “green”-propellant propulsion systems for single engines. However, in spacecraft control engine systems their number may amount to 8–16; in addition, they operate in different regimes and may differ in thrust/throttling characteristics, which leads to unstable propellant feed to operating engines. To predict these processes, the paper suggests a mathematical model developed at the Institute of Technical Mechanics of the National Academy of Sciences of Ukraine and the State Space Agency of Ukraine and adapted to “green”-propellant engine systems. The model serves to calculate the operation of low-thrust jet engine systems and describes the propellant flow in propellant feed lines, propellant valves, and combustion chambers. To implement the model, use was made of the results of experimental studies on a prototype “green”-propellant engine developed at Yuzhnoye State Design Office. The analysis of the experimental results made it possible to refine the performance parameters of the monopropellant employed and obtain computational data that may be used in analyzing the operation of a single engine or an engine system on this propellant type in ground and flight conditions

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Sangwan, Preeti, i Nibedita Banik. "Study on geosynchronous satellite launch vehicle propellants and combustion mechanism of each stage". E3S Web of Conferences 391 (2023): 01030. http://dx.doi.org/10.1051/e3sconf/202339101030.

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GSLV is a “geosynchronous satellite launch vehicle” which aims at launching space objects into GTO- Geosynchronous transfer orbit. This paper provides a brief idea of the chemistry of propellants used in all three stages and strap-on motors of geosynchronous satellite launch vehicles and their combustion mechanism. It includes all series of GSLVs launched till now and a description of criteria for choosing fuel. This paper also includes a brief description on hydrazine which is a basic part of so many propellant combinations. Furthermore, it includes basic reasons which result in unsuccessful ignition especially at cryogenic. It also emphasizes on reasons for modification in fuels over time and advancement in efficiency obtained due to respective modified fuels, further, giving an overview of future ideas in the development of propellants.

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Boenish, Hans, Carlos Garcia, Prashanth Bangalore Venkatesh, Jack Costello, Evan Daniel, Michael Fitzpatrick, Curtis Foster i in. "111 N HYDRAZINE BIPROPELLANT ENGINE (HBE) WITH GAS-GAS INJECTION". International Journal of Energetic Materials and Chemical Propulsion 22, nr 2 (2023): 61–72. http://dx.doi.org/10.1615/intjenergeticmaterialschemprop.v22.i2.50.

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A thruster, designated LE111, utilizes hydrazine and MON3 as fuel and oxidizer and produces a thrust of 111 N at nominal operating conditions with an Isp of up to 328 s. The thruster is throttleable through the use of separate fuel and oxidizer metering valves and is able to transition to a hydrazine monopropellant mode at any point during its operation. Completed qualification testing has demonstrated a versatile operating box that includes chamber pressure-mixture ratio excursions, heated propellants up to 341 K, and gaseous helium ingestion through propellant flow paths. Overall, the thruster has achieved 15,455 s of accumulated on-time and a maximum continuous burn time of 6,000 s. The thruster achieves its performance through a novel micro-coaxial gas-gas injection scheme and an innovative regeneratively cooled combustion chamber, which uses the oxidizer as the working fluid. The thruster's capabilities and performance recorded during the completed qualification testing are described, and its design is outlined. This paper is published with the permission of the authors granted to 3AF – Association Aéronautique et Astronautique de France (www.3AF.fr) organizer of the Space Propulsion International conference.

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Verma, Mohan, B. L. Gupta i M. Pandey. "Formulation & Storage Studies on Hydrazine-Based Gelled Propellants." Defence Science Journal 46, nr 5 (1.01.1996): 435–42. http://dx.doi.org/10.14429/dsj.46.4315.

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Buntrock, L. J., M. Grabe i H. Fischer. "Contamination assessment of a freely expanding green propellant thruster plume". IOP Conference Series: Materials Science and Engineering 1287, nr 1 (1.08.2023): 012004. http://dx.doi.org/10.1088/1757-899x/1287/1/012004.

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Abstract A number of propellant/thruster combinations are under development in recent years that aim to replace the prevailing hydrazine-driven reaction control thrusters with less hazardous substances (“green propellants”). With some of these systems already in orbit, characterizing their contamination potential in a space environment becomes relevant. In this paper we discuss experiments on plume induced contamination from a novel propene/nitrous oxide bipropellant thruster, including high-speed imaging, SEM-EDS analysis, QCM measurements and in-situ mass spectrometry. Additional measurements of combustion chamber pressure complement the overall characterization of the thruster performance in a high vacuum environment. The main findings of this exploratory study are strong indications of solid and liquid phase particles being ejected from the nozzle, which will be investigated in a subsequent phase of the activity.

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Yoon, Wonjae, Vikas Khandu Bhosale i Hosung Yoon. "Reactor Structure for the Decomposition of ADN-Based Monopropellant". Aerospace 10, nr 8 (31.07.2023): 686. http://dx.doi.org/10.3390/aerospace10080686.

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Ammonia dinitramide (ADN)-based liquid monopropellants are considered to be environmentally friendly alternatives to the toxic and carcinogenic hydrazine-based propellants. Hence, Space Solutions Co., Ltd. is developing a 1N ADN-based liquid monopropellant thruster by conducting a combustion performance in different types of reactors. Various parameters, such as preheating temperature and the size of thermal and catalyst beds, were examined. The results showed that the decomposition of the propellant in a Pt-LHA catalyst bed, which was used in the Type-1 reactor, resulted in insufficient combustion at low preheating temperatures. Furthermore, increasing the preheating temperature led to partial reaction of the propellant, but resulted in low combustion efficiency due to disintegration of the catalyst. However, when a thermal bed (STS ball) was used in addition to the catalyst bed (Pt-LHA) in the Type-2 and Type-3 reactors, the combustion efficiency was improved, with a minimal pressure drop of 0.2 bar. It was also confirmed that the catalyst was not damaged even after repeated operations. In conclusion, this study suggests that the propellant needs to vaporize before decomposing on the catalyst bed to achieve optimal combustion efficiency.

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Wu, Jin, Frederick Nii Ofei Bruce, Xin Bai, Xuan Ren i Yang Li. "Insights into the Reaction Kinetics of Hydrazine-Based Fuels: A Comprehensive Review of Theoretical and Experimental Methods". Energies 16, nr 16 (16.08.2023): 6006. http://dx.doi.org/10.3390/en16166006.

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While researchers have extensively studied the initial decomposition mechanism of Monomethylhydrazine (MMH, CH3NHNH2) in the MMH/dinitrogen tetroxide (NTO) system, the investigation of Unsymmetrical Dimethylhydrazine (UDMH, (CH3)2NNH2) has been limited due to its high toxicity, corrosiveness, and deterioration rate. Hence, the effects of UDMH’s deterioration products on combustion performance and gas-phase combustion reaction mechanisms remain unclear. This comprehensive review examines the existing research on the reaction kinetics of the three widely used hydrazine-based self-ignition propellants: Hydrazine (HZ, N2H4): MMH: and UDMH, emphasizing the necessity for further investigation into the reaction kinetics and mechanisms of UDMH. It also discusses the implications of these findings for developing safer and more efficient rocket propulsion systems. Additionally, this review underscores the importance of utilizing computational chemistry theory to analyze hydrazine-based fuels’ combustion and decomposition properties, constructing detailed pyrolysis and combustion reaction mechanisms to optimize rocket engine fuel performance and environmental concerns.

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Schwertz, Hansjrg, Lisa A. Roth i Daniel Woodard. "Propellant Off-Gassing and Implications for Triage and Rescue". Aerospace Medicine and Human Performance 91, nr 12 (1.12.2020): 956–61. http://dx.doi.org/10.3357/amhp.5637.2020.

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INTRODUCTION: Hypergolic propellants can be released in large amounts during space launch contingencies. Whether propellant-contaminated suit fabric poses a significant risk to rescue crews, due to off-gassing, has not been explored in detail. In this study, we addressed this issue experimentally, exposing space suit fabric to propellants (dinitrogen tetroxide [N2O4] and monomethyl hydrazine [MMH]).METHODS: The NASA Space Shuttle Program Advanced Crew Escape System II (ACES II) is similar to the NASA Orion Crew Survival System (OCSS) and was utilized here. Suit fabric was placed and sealed into permeation cells. Fabric exterior surface was exposed to constant concentrated hypergolics, simulating permeation and leakage. Fabric was rinsed, and permeation and off-gassing kinetics were measured. Experimental parameters were selected, simulating suited flight crewmembers during an evacuation transport without cabin air flow.RESULTS: The fabric allows for immediate permeation of liquid or vaporized MMH and N2O4. NO2 off-gassing never exceeded the AEGL-1 8-h level (acute exposure guideline level). In contrast, MMH off-gassing levels culminated in peak levels, approaching AEGL-2 10-min levels, paralleling the drying process of the fabric layers. DISCUSSION: Our findings demonstrate that MMH off-gassing is promoted by the drying of suit material in a delayed fashion, resulting in MMH concentrations having the potential for adverse health effects for flight and rescue crews. This indicates that shorter decontamination times could be implemented, provided that suit material is either kept moist to prevent off-gassing or removed prior to medical evacuation. Additional studies using OCSS or commercial crew suits might be needed in the future.Schwertz H, Roth LA, Woodard D. Propellant off-gassing and implications for triage and rescue. Aerosp Med Hum Perform. 2020; 91(12):956961.

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Morrison, Gale. "Shuttle Diplomacy". Mechanical Engineering 121, nr 03 (1.03.1999): 52–55. http://dx.doi.org/10.1115/1.1999-mar-1.

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The article highlights key points of a special National Research Council (NRC) committee on Space Shuttle upgrades’ ‘Upgrading the Space Shuttle’ report. The NRC committee reviewed two $1 billion-plus proposals for changing what NASA uses to propel the orbiters to space, and found that these could be broached only if more flights were planned, much more design review was done, and the Shuttle would be in service after 2012. The committee used NASA's grouping of the proposed upgrades into phases, with one being the least expensive, time-consuming, and risky, and four being the most costly, long term, and risk-prone. The committee studied another upgrade that would eliminate a hazardous material. The upgrade would modify the Shuttle's orbital manoeuvring and reaction control systems to use liquid oxygen and ethanol propellants instead of current engines' toxic N2O4 and monomethyl hydrazine propellants.

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Whitmore, Stephen A. "Nytrox as “Drop-in” Replacement for Gaseous Oxygen in SmallSat Hybrid Propulsion Systems". Aerospace 7, nr 4 (12.04.2020): 43. http://dx.doi.org/10.3390/aerospace7040043.

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A medical grade nitrous oxide (N2O) and gaseous oxygen (GOX) “Nytrox” blend is investigated as a volumetrically-efficient replacement for GOX in SmallSat-scale hybrid propulsion systems. Combined with 3-D printed acrylonitrile butadiene styrene (ABS), the propellants represent a significantly safer, but superior performing, alternative to environmentally-unsustainable spacecraft propellants like hydrazine. In a manner analogous to the creation of soda-water using dissolved carbon dioxide, Nytrox is created by bubbling GOX under pressure into N2O until the solution reaches saturation. Oxygen in the ullage dilutes N2O vapor and increases the required decomposition energy barrier by several orders of magnitude. Thus, risks associated with inadvertent thermal or catalytic N2O decomposition are virtually eliminated. Preliminary results of a test-and-evaluation campaign are reported. A small spacecraft thruster is first tested using gaseous oxygen and 3-D printed ABS as the baseline propellants. Tests were then repeated using Nytrox as a “drop-in” replacement for GOX. Parameters compared include ignition reliability, latency, initiation energy, thrust coefficient, characteristic velocity, specific impulse, combustion efficiency, and fuel regression rate. Tests demonstrate Nytrox as an effective replacement for GOX, exhibiting a slightly reduced specific impulse, but with significantly higher volumetric efficiency. Vacuum specific impulse exceeding 300 s is reported. Future research topics are recommended.

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Rees, Andreas, i Michael Oschwald. "Cryogenic test bench for the experimental investigation of cryogenic injection in rocket combusters under high-altitude conditions". IOP Conference Series: Materials Science and Engineering 1240, nr 1 (1.05.2022): 012103. http://dx.doi.org/10.1088/1757-899x/1240/1/012103.

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Abstract Due to current and future environmental and safety issues in space propulsion, typical propellants for upper stage or satellite rocket engines such as the toxic hydrazine are going to be replaced by green propellants like the combination of liquid oxygen and hydrogen or methane. The injection of that kind of cryogenic fluid into the vacuum atmosphere of space leads to a superheated state, which results in a sudden and eruptive atomization due to flash boiling. For a detailed experimental investigation of superheated cryogenic fluids the new cryogenic test bench M3.3 with a temperature controlled injection system at high-altitude conditions was built at DLR Lampoldshausen. First run-in tests as well as several measurement campaigns with liquid nitrogen as the test fluid showed the performance and suitability of the new test bench for the systematical investigation of cryogenic flash boiling. Besides new insights into the flash boiling process of cryogenic liquids, the experimental data of cryogenic flash boiling generated with this test bench provide a comprehensive database for the validation of numerical models and further numerical investigations.

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Daimon, Wataru, Masafumi Tanaka i Itsuro Kimura. "The mechanisms of explosions induced by contact of hypergolic liquid propellants, hydrazine and nitrogen tetroxide". Symposium (International) on Combustion 20, nr 1 (styczeń 1985): 2065–71. http://dx.doi.org/10.1016/s0082-0784(85)80708-6.

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Nosseir, Ahmed E. S., Angelo Cervone i Angelo Pasini. "Review of State-of-the-Art Green Monopropellants: For Propulsion Systems Analysts and Designers". Aerospace 8, nr 1 (15.01.2021): 20. http://dx.doi.org/10.3390/aerospace8010020.

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Current research trends have advanced the use of “green propellants” on a wide scale for spacecraft in various space missions; mainly for environmental sustainability and safety concerns. Small satellites, particularly micro and nanosatellites, evolved from passive planetary-orbiting to being able to perform active orbital operations that may require high-thrust impulsive capabilities. Thus, onboard primary and auxiliary propulsion systems capable of performing such orbital operations are required. Novelty in primary propulsion systems design calls for specific attention to miniaturization, which can be achieved, along the above-mentioned orbital transfer capabilities, by utilizing green monopropellants due to their relative high performance together with simplicity, and better storability when compared to gaseous and bi-propellants, especially for miniaturized systems. Owing to the ongoing rapid research activities in the green-propulsion field, it was necessary to extensively study and collect various data of green monopropellants properties and performance that would further assist analysts and designers in the research and development of liquid propulsion systems. This review traces the history and origins of green monopropellants and after intensive study of physicochemical properties of such propellants it was possible to classify green monopropellants to three main classes: Energetic Ionic Liquids (EILs), Liquid NOx Monopropellants, and Hydrogen Peroxide Aqueous Solutions (HPAS). Further, the tabulated data and performance comparisons will provide substantial assistance in using analysis tools—such as: Rocket Propulsion Analysis (RPA) and NASA CEA—for engineers and scientists dealing with chemical propulsion systems analysis and design. Some applications of green monopropellants were discussed through different propulsion systems configurations such as: multi-mode, dual mode, and combined chemical–electric propulsion. Although the in-space demonstrated EILs (i.e., AF-M315E and LMP-103S) are widely proposed and utilized in many space applications, the investigation transpired that NOx fuel blends possess the highest performance, while HPAS yield the lowest performance even compared to hydrazine.

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Ray, Triparna, i Vinayak Malhotra. "Hydrogen Based Compounds as Energetic Catalysts for Liquid Rocket Engines: Implications and Applications". Asian Review of Mechanical Engineering 10, nr 1 (15.05.2021): 8–17. http://dx.doi.org/10.51983/arme-2021.10.1.2868.

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In the current scenario of space propulsion, liquid propellants have significantly proved useful in the upper stage rocket engines. Over the past couple decades, the world had inclined positively towards cryogenic fuel(s) viz., liquid oxygen and liquid hydrogen due to their high specific impulse. A higher specific impulse implies lower duration to achieve design cruise velocity for a given rocket initial and instantaneous mass. Liquid hydrogen and liquid oxygen as fuel and oxidizer can generate one of the highest enthalpy release in combustion, producing a specific impulse of up to 450 seconds at an effective exhaust velocity of 4.4 kilometres per second. Whereas, selected disadvantages are encountered in the form of storage and production. This indicates overdependence on cryogenic propellants and has necessitated the active research effort for better alternatives. As an interesting alternative, the combination of Dinitrogen Tetroxide (N2O4) and Monomethyl Hydrazine (MMH) have been used for many space applications owing to an extreme storage stability and hypergolic nature. Present study aims to express the effect of hydrogen-based compounds on the rocket performance. Four distinctive compounds from two groups of hydrogen-based compounds are tested with the varying oxidizer and fuel proportions to obtain a new, cost-effective and user-friendly composition that can be prepared at room temperature. The investigation attempt and explains the effect of hydrogen based energetic propellants using N2O4 and MMH as the base composition for upper stage performance. The work is motivated by the need of efficient space operations with attractive propulsive alternatives to minimize over-dependence on cryogenics, which will ultimately result in cost effectiveness. Various energetic materials were tested with the base composition by using standard NASA-CEA complex chemical equilibrium model. The performance was evaluated in terms of variation in specific impulse and characteristic velocity both of which are significant parameters. To, validate the practical utility, the role of chamber pressure, supersonic area ratio and optimal Oxidizer to fuel ratio (O/F) was determined. The work led to two interesting findings, a composition of beryllium hydride with base composition for high performance of rockets and the negative impact of hydrogen on liquid propellants.

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Titi, H. M., J. M. Marrett, G. Dayaker, M. Arhangelskis, C. Mottillo, A. J. Morris, G. P. Rachiero, T. Friščić i R. D. Rogers. "Hypergolic zeolitic imidazolate frameworks (ZIFs) as next-generation solid fuels: Unlocking the latent energetic behavior of ZIFs". Science Advances 5, nr 4 (kwiecień 2019): eaav9044. http://dx.doi.org/10.1126/sciadv.aav9044.

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Hypergolic materials, capable of spontaneous ignition upon contact with an external oxidizer, are of critical importance as fuels and propellants in aerospace applications (e.g., rockets and spacecraft). Currently used hypergolic fuels are highly energetic, toxic, and carcinogenic hydrazine derivatives, inspiring the search for cleaner and safer hypergols. Here, we demonstrate the first strategy to design hypergolic behavior within a metal-organic framework (MOF) platform, by using simple “trigger” functionalities to unlock the latent and generally not recognized energetic properties of zeolitic imidazolate frameworks, a popular class of MOFs. The herein presented six hypergolic MOFs, based on zinc, cobalt, and cadmium, illustrate a uniquely modular platform to develop hypergols free of highly energetic or carcinogenic components, in which varying the metal and linker components enables the modulation of ignition and combustion properties, resulting in excellent hypergolic response evident by ultrashort ignition delays as low as 2 ms.

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Amariei, Daniel, Sylvie Rossignol i Charles Kappenstein. "Shape Forming of Alumina-Silica of High Thermal Stability for Space Propulsion Applications". Advances in Science and Technology 45 (październik 2006): 427–35. http://dx.doi.org/10.4028/www.scientific.net/ast.45.427.

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The replacement of toxic hydrazine used for catalytic propulsion by less toxic propellants such as ionic liquids is of hot interest. The challenge for this replacement is the formulation, development and shape forming of new catalysts. Efficient catalysts for the decomposition of aqueous 79 wt.-% HAN solutions (hydroxylammonium nitrate NH3OH+NO3 -) contain 10 wt.-% Pt active phase deposited on a support. Laboratory-made powder catalysts contain platinum supported on Si-doped alumina and display a good activity at low temperature. But, for industrial applications in propulsion thrusters, the pressure drop due to a powder is too high and consequently shape formed supports and catalysts must be prepared and investigated. Two catalyst types have been prepared (i) from shaped supports obtained at the laboratory level using the “oil-drop” method and (ii) from supports formed through an industrial procedure. Both shape formed samples display comparable properties as the powder support, such as high thermal stability linked to the presence q and d aluminas and similar BET surface area. Catalysts based on these supports show efficient catalytic activities.

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Tarchoun, Ahmed Fouzi, Djalal Trache, Amir Abdelaziz, Abdelatif Harrat, Walid Oussama Boukecha, Mohamed Abderrahim Hamouche, Hani Boukeciat i Mohammed Dourari. "Elaboration, Characterization and Thermal Decomposition Kinetics of New Nanoenergetic Composite Based on Hydrazine 3-Nitro-1,2,4-triazol-5-one and Nanostructured Cellulose Nitrate". Molecules 27, nr 20 (17.10.2022): 6945. http://dx.doi.org/10.3390/molecules27206945.

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This research aims to develop new high-energy dense ordinary- and nano-energetic composites based on hydrazine 3-nitro-1,2,4-triazol-5-one (HNTO) and nitrated cellulose and nanostructured nitrocellulose (NC and NMCC). The elaborated energetic formulations (HNTO/NC and HNTO/NMCC) were fully characterized in terms of their chemical compatibility, morphology, thermal stability, and energetic performance. The experimental findings implied that the designed HNTO/NC and HNTO/NMCC formulations have good compatibilities with attractive characteristics such as density greater than 1.780 g/cm3 and impact sensitivity around 6 J. Furthermore, theoretical performance calculations (EXPLO5 V6.04) displayed that the optimal composition of the as-prepared energetic composites yielded excellent specific impulses and detonation velocities, which increased from 205.7 s and 7908 m/s for HNTO/NC to 209.6 s and 8064 m/s for HNTO/NMCC. Moreover, deep insight on the multi-step kinetic behaviors of the as-prepared formulations was provided based on the measured DSC data combined with isoconversional kinetic methods. It is revealed that both energetic composites undergo three consecutive exothermic events with satisfactory activation energies in the range of 139–166 kJ/mol for HNTO/NC and 119–134 kJ/mol for HNTO/NMCC. Overall, this research displayed that the new developed nanoenergetic composite based on nitrated cellulose nanostructure could serve as a promising candidate for practical applications in solid rocket propellants and composite explosives.

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Jung, Park, Kang i Kim. "Hydrazine-Selective Fluorescent Turn-On Probe Based on Ortho-Methoxy-Methyl-Ether (o-MOM) Assisted Retro-aza-Henry Type Reaction". Sensors 19, nr 20 (17.10.2019): 4525. http://dx.doi.org/10.3390/s19204525.

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Hydrazine (N2H4) is one of the most widely used industrial chemicals that can be utilized as a precursor of pesticides, pharmaceutics, and rocket propellant. Due to its biological and environmental toxicity with potential health risks, various sensing tools have been developed. Among them, fluorescence-based molecular sensing systems have been highlighted due to its simple-operation, high selectivity and sensitivity, and biocompatibility. In our recent report, we disclosed a ratiometric type fluorescent probe, called HyP-1, for the detection of hydrazine, which is based on ortho-methoxy-methyl-ether (o-MOM) moiety assisted hydrazone-formation of the donor (D)-acceptor (A) type naphthaldehyde backbone. As our follow-up research, we disclose a turn-on type fluorescent probe, named HyP-2, as the next-generation hydrazine probe. The sensing rational of HyP-2 is based on the o-MOM assisted retro-aza-Henry type reaction. The dicyanovinyl moiety, commonly known as a molecular rotor, causes significant emission quenching of a fluorescent platform in aqueous media, and its cleavage with hydrazone-formation, which induces a significant fluorescence enhancement. The high selectivity and sensitivity of HyP-2 shows practical explicabilities, including real-time paper strip assay, vapor test, soil analysis, and real water assay. We believe its successful demonstrations suggest further applications into a wide variety of fields.

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24

A Whitmore, Stephen. "Development and testing of an all-additively manufactured hybrid thruster for smallsats". Aeronautics and Aerospace Open Access Journal 5, nr 2 (10.08.2021): 66–81. http://dx.doi.org/10.15406/aaoaj.2021.05.00129.

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Background: The design, development, and testing of a small-thruster system with additively-manufacturing key components is presented. The primary issue associated with conventionally-manufactured small thruster systems is the assembly complexity, where the motor case, injector, ignition electrodes, nozzle retainer, nozzle, fuel grain, insulting liner, and other components are fabricated individually and then assembled. For very small thruster systems, this detailed fabrication and assembly process is extremely labor intensive and time-consuming. Proposed "all- additive" designs reduce component fabrication and procurement cycle time, and may significantly reduce overall system complexity. Before committing to hardware, a student-lead design team reduced the trade-space to 2 design-options. Each option employs multiple additively-manufactured components including the oxidizer delivery system attachments, motor cap, motor casing, insulation, and the fuel grain. Components are additively manufactured using one of three different methods, fused-deposition modeling (FDM), stereo lithography (SL), and non-galvanic nickel plating (EN). Both designs feature an FDM-fabricated ABS fuel grain, with 1) a two material combustion chamber assembly fabricated from Veroclear® plastic using Polyjet 3-D SL printing technology, and 2) a chamber/fuel assembly additively fabricated from ABS, but plated with an external nickel coating. For simplicity the student prototype employs gaseous oxygen (GOX) and additively manufactured acrylonitrile-butadiene-styrene (ABS) as propellants. ABS has been previously demonstrated to be a highly efficient hybrid fuel material. The research campaign emphasized multiple objectives including hot and cold material testing burn lifetime survivability, system restart capability, and overall performance. Performance comparisons with hydrazine are presented.

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LEE, Yang-Suk, i Jun Hwan JANG. "The design and performance on 200N-class bipropellant rocket engine using decomposed H2O2 and Kerosene". INCAS BULLETIN 11, nr 3 (9.09.2019): 99–110. http://dx.doi.org/10.13111/2066-8201.2019.11.3.9.

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Mono-propellant thrusters are widely utilized in satellites and space launchers. In many cases, they are using hydrazine as a propellant. However, hydrazine has high toxicity and high risks in using for launch campaign. Recently, low-toxic (green) propellant is being highlighted as a replacement for hydrazine. In this paper, 200N bi-propellant engine using hydrogen peroxide/kerosene was designed/manufactured, and the spray or atomization characteristic and inflation pressure were determined by cold flow test, and combustion and pulse tests in a single cycle same as previous methods were conducted. As uniformly supplying hydrogen peroxide through plate-type orifice to a catalyst bed, the hot gas was created as a reaction with hydrogen and catalyst. And then, it was confirmed that the ignition is possible on the wide range of O/F ratio without additional ignition source. The liquid rocket engine with bi-propellant of hydrogen peroxide/kerosene and design/test methods which developed in this study are expected to be utilized as an essential database for designing of the ignitor/injector of bi-propellant liquid rocket engine using hydrogen peroxide/kerosene with high-thrust/performance in near future.

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Wei, Xiangshuai, Wei Huang, Qianyang Lv, Tianyou Zeng, Yuji Liu i Yongxing Tang. "Self-assembly Hybridization of CL-20 and Hydrazone-based Polymeric Carbon Nitrides for High Performance Explosive". Journal of Physics: Conference Series 2478, nr 4 (1.06.2023): 042006. http://dx.doi.org/10.1088/1742-6596/2478/4/042006.

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Abstract A strategy for desensitization of the highly sensitive explosive CL-20 with polymeric carbon nitrides is described. The hybrid energetic material (MHGP-CL-20) was synthesized via a self-assembly approach, where CL-20 molecules are immobilized on the hydrazone-based polymeric carbon nitrides. The good detonation performances (detonation velocity 9608 m·s−1, detonation pressure 42.8 GPa) show that MHGP-CL-20 retains the excellent performance of CL-20 to the greatest extent. More importantly, its sensitivities were effectively reduced with the impact sensitivity (IS) 10 J and the friction sensitivity (FS) 160 N, which is much lower compared with raw ε-CL-20 (IS: 4 J; FS: 94 N). In addition, its specific impulse was improved to 276.6 s, higher than that of ε-CL-20 (272.4 s). By preparing solid composite propellants, the burning rate of the propellant grain PMC20 based on MHGP-CL-20 is higher than PC20 based on ε-CL-20. The addition of hybrid energetic complex could keep the stability of combustion and improve the burning rate of solid propellant. The combination of PCNs material and CL-20 sustains the excellent performance of CL-20 and reduces the sensitivity effectively. The preparation of hybrid energetic material MHGP-CL-20 finds a new balance in the contradictory system of high energy and low sensitivity.

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Johnson, Christyl C., i Michael R. Duffey. "Environmental Life Cycle Criteria for Propellant Selection Decision-Making". International Journal of Space Technology Management and Innovation 2, nr 1 (styczeń 2012): 16–29. http://dx.doi.org/10.4018/ijstmi.2012010102.

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A system of previously undefined environmental life cycle cost elements were developed for use in the propellant selection processes for spacecraft launch propulsion systems, with input from the National Aeronautics and Space Administration (NASA), the Swedish Space Corporation, and stakeholders in industry and academia. These environmental life cycle cost elements were incorporated into a life cycle cost analysis of toxic propellant (hydrazine) versus green (High Performance Green Propellant) through a modified cost benefit analysis. Environmental cost element line items within the life cycle were identified as costs or benefits (cost reductions or avoided costs). A case study was also implemented to further illustrate these findings, resulting in a real-world 66% reduction in Phase E (operational) mission cost for High Performance Green Propellant (HPGP) compared with hydrazine. Based on the analysis, the largest environmental cost drivers were facility operations and maintenance, end of life disposal, and transportation, with the major costs being associated with health and human safety protection.

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Subramanian, Selvakumar, Somanathan Narayanasastri i Audisesha Reddy Kami Reddy. "Doping-induced detection and determination of propellant grade hydrazines by a kinetic spectrophotometric method based on nano and conventional polyaniline using halide ion releasing additives". RSC Adv. 4, nr 52 (2014): 27404–13. http://dx.doi.org/10.1039/c4ra02296c.

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Adami, Amirhossein, Mahdi Mortazavi, Mehran Nosratollahi, Mohammadreza Taheri i Jalal Sajadi. "Multidisciplinary Design Optimization and Analysis of Hydrazine Monopropellant Propulsion System". International Journal of Aerospace Engineering 2015 (2015): 1–9. http://dx.doi.org/10.1155/2015/295636.

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Monopropellant propulsion systems are widely used especially for low cost attitude control or orbit correction (orbit maintenance). To optimize the total propulsion system, subsystems should be optimized. Chemical decomposition, aerothermodynamics, and structure disciplines demand different optimum condition such as tank pressure, catalyst bed length and diameter, catalyst bed pressure, and nozzle geometry. Subsystem conflicts can be solved by multidisciplinary design optimization (MDO) technique with simultaneous optimization of all subsystems with respect to any criteria and limitations. In this paper, monopropellant propulsion system design algorithm is presented and the results of the proposed algorithm are validated. Then, multidisciplinary design optimization of hydrazine propulsion system is proposed. The goal of optimization can be selected as minimizing the total mass (including propellant), minimizing the propellant mass (maximizing the Isp), or minimizing the dry mass. Minimum total mass, minimum propellant mass, and minimum dry mass are derived using MDO technique. It is shown that minimum total mass, minimum dry mass, and minimum propellant mass take place in different conditions. The optimum parameters include bed-loading, inlet pressure, mass flow, nozzle geometry, catalyst bed length and diameter, propellant tank mass, specific impulse (Isp), and feeding mass which are derived using genetic algorithm (GA).

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He, Lei, Binglian Liang, Yanqiang Huang i Tao Zhang. "Design strategies of highly selective nickel catalysts for H2 production via hydrous hydrazine decomposition: a review". National Science Review 5, nr 3 (29.09.2017): 356–64. http://dx.doi.org/10.1093/nsr/nwx123.

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Abstract Hydrazine, a widely used liquid propellant, has the potential to be employed as a hydrogen source in certain instances and has therefore attracted considerable attention; consequently, the complete decomposition of hydrazine with 100% H2 selectivity under mild conditions has become the current research focus for catalyst design. In this review, the strategies for the design of efficient catalysts are summarized for complete hydrazine decomposition. The first part of this review introduces the mechanism of hydrazine decomposition, while the second part illustrates the key factors influencing the H2 selectivity of nickel catalysts, including the effects of alloying, alkali promoter addition and strong metal–support interactions. Finally, the critical elements of catalyst design employed in industrial applications are analyzed.

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Gou, Xiao Li, i Xuan Jun Wang. "The Combined Processing Technology Research of the Naturally Purification and Artificial Wetland to Dimethyl Hydrazine Waste Water". Advanced Materials Research 518-523 (maj 2012): 2881–85. http://dx.doi.org/10.4028/www.scientific.net/amr.518-523.2881.

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In accordance with the shortcoming of naturally purification processing to liquid propellant dimethyl hydrazine waste water, the paper is putting forward the combined processing technology of naturally purification and artificial wetland. Designed process flow of the combined processing technology, and the naturally purification and artificial wetland dealing with the structure of pond, and to his processing dimethyl hydrazine the effect to imitate waste water has been in progress research. The result indicates: the technology can effective remove dimethyl hydrazine and his degradation product in the waste water, and the back waste water of processing achieves the placing in proper order quota.

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Krishnamachary, S., S. Krishna Mohan, S. G. Kulkarni, D. Jayaraman, M. Raghavendra Rao, L. Dev Singh i Sai Krishna Prasad. "Propellant Grade Hydrazine in Mono/Bi-propellant Thrusters: Preparation and Performance Evaluation". Defence Science Journal 65, nr 1 (26.02.2015): 31–38. http://dx.doi.org/10.14429/dsj.65.7986.

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Kundu, Pijus, A. Ray Chaudhuri, S. Das i T. K. Bhattacharyya. "Compatibility Study of Diamond-Like Nanocomposite Thin Films with Hydrazine Propellant for MEMS Microthruster". Advanced Materials Research 74 (czerwiec 2009): 269–72. http://dx.doi.org/10.4028/www.scientific.net/amr.74.269.

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In this paper, the etching characteristic of diamond like nanocomposite thin films materials in hydrazine has been reported. The experiments have been carried out to explore the compatibility of hydrazine as a propellant with silicon based microthruster. In the reported work, 2″ N-type (100) silicon wafer with 4-6 Ω cm resistivity were used as base material. Diamond-like nanocomposite (DLN) films are deposited on silicon substrate by plasma enhanced chemical vapor deposition (PECVD) process using siloxane or silazane based precursors or their combinations. Thickness of deposited DLN thin films is around 1 µm. DLN samples are treated in 98% hydrazine at 25 °C, 70 °C and 90 °C for different time and etch rates and subsequently the change in refractive index of the DLN films if any has been measured.

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Pozdieiev, H. L., i Ye E. Litau. "Fueling-neutralization stations. New developments and applications". Kosmičeskaâ tehnika. Raketnoe vooruženie 2023, nr 1 (12.05.2023): 48–55. http://dx.doi.org/10.33136/stma2023.01.048.

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The article dwells on development and study of the multifunctional operations while preparing propellant components for launch vehicle tank filling by high-boiling propellant components at the neutralization stations. The article considers the preparation of propellant for filling the launch vehicle stages with high-boiling propellant components of nitrogen tetroxide (oxidizer) and unsymmetrical dimethyl hydrazine (fuel) in terms of propellant saturation with helium and denitrogenation. Usually these issues refer to the common technology of propellant preparation and are tackled sequentially: first, propellant is drained into the filling tank of the filling system, then the propellant is denitrogened, for example purging the propellant by helium under atmospheric pressure in the tank, then propellant is saturated with helium to the given concentration by bubbling helium in the propellant, maintaining the set pressure of helium in the tank. This technology significantly complicates the process of propellant preparation, increases helium consumption, as well as the amount of the generated vapor, which requires recycling in the neutralization units. This article studies multifunctional operations, where the propellant is simultaneously drained from delivery vehicles, saturated with helium and denitrogenated. Amount of residual nitrogen in the propellant and the main direction of deep denitrogenation of the propellant are calculated. Amount of generated vapor and consumed helium are determined. The process of propellant draining by extrusion, maintaining the given pressure in the tank and alternating the propellant drain on the closed vent device (compression) and open vent device (decompression) is studied. As a result, the theoretical justification of multifunctional operations in preparation of high–boiling propellant components to fill the launch-vehicle stages is presented. Key words: saturation with helium and denitrogenation of the propellant, drain with closed vent device, excessive pressure draining, gas-vapor mixture, neutralization system.

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LI Qiang, 李. 强., 张宝辉 ZHANG Bao-hui, 李会锋 LI Hui-feng, 王. 谦. WANG Qian i 王. 超. WANG Chao. "Estimation of hydrazine propellant leakage for LEO satellite". Optics and Precision Engineering 27, nr 11 (2019): 2354–64. http://dx.doi.org/10.3788/ope.20192711.2354.

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Liu, Z. X., Y. M. Wei, C. Zhou, W. Li i Y. T. Cong. "Compatibility of an elastomeric material with hydrazine propellant". IOP Conference Series: Materials Science and Engineering 479 (8.03.2019): 012098. http://dx.doi.org/10.1088/1757-899x/479/1/012098.

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Si, Ping Jun, Hua Wang, Cun Yan Cui i Yuan Chen. "Simulation Study of Space Spiral Gas-Liquid Separation Technology". Applied Mechanics and Materials 268-270 (grudzień 2012): 902–5. http://dx.doi.org/10.4028/www.scientific.net/amm.268-270.902.

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The advantages and disadvantages of the method of separating the liquid from the gas on orbit are analyzed aiming at the propellant resupplying on orbit. A new method named spiral gas-liquid separation is proposed here, which is much simpler and highly efficient. Supposing the hydrazine as the propellant, the flow process of two-phase flow is numerical calculated. The results shows that the separated liquid would acquire higher speed and it would take shorter time for the fluid field to be balanced if the inlet fluid speed is higher with a constant gas-liquid ratio at the inlet. The same would take place if the ratio of the liquid to the gas is higher with a constant inlet speed.

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Tuncer, S. K., M. Durusu, I. Arziman, Y. E. Eyi, A. Bayir, U. Kaldirim, A. O. Yildirim i M. Eryilmaz. "(P2-66) Experience of 14 Cases Exposed to Hydrazine". Prehospital and Disaster Medicine 26, S1 (maj 2011): s157. http://dx.doi.org/10.1017/s1049023x11005103.

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Hydrazine, a highly toxic agent is mainly used as a high-energy rocket propellant or reactant in military fuel cells, in nickel plating, in the polymerization of urethane, for removal of halogens from wastewater, as an oxygen scavenger in boiler feedwater to inhibit corrosion, and in photographic development. Short-term exposure to high levels of Hydrazine may cause irritation of eyes, nose, and throat, headache, nausea, dizziness, pulmonary edema, seizures, and coma. Acute exposure can also damage liver, kidneys, and central nervous system. Dermatitis may develop by skin contact. In this article we aimed to present our experience belongs to 14 cases exposed to Hydrazine. Cases were evaluated retrospectively based on demographic data, exposure type, approximate exposure time, clinical features, lab analyzes and results of follow-up. Cases were all male personnel. Mean age and standard deviation were 30,28 and 6,73 respectively. All cases were exposed to Hydrazine in an open place during the monitorization of aircraft for a couple of seconds. Personnel were presented to feel an odor similar to garlic in their nasopharynx. Retrosternal burning was the preponderant symptom in 6 of the cases. The vital signs and physical examination provided no valuable data. Evaluation of Whole Blood Count, Arterial Blood Gas, Biochemical Parameters, Urine Tests, ECG and Chest Radiograph took place in diagnosis period. Respiration function tests were performed on the 6 of the cases who had respiratory complaints. All tests revealed unremarkable data. All cases were subjected to reevaluation in the end of next 48 hours. No complications were encountered on the next examination. Our cases presented no mortality and complication due to having information about Hydrazine and short-term exposure and exposure in open place. Of personnel working in such places including Hydrazine, having information about Hydrazine, is the leading factor in preventing mortality and complications of Hydrazine.

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Subramanian, Selvakumar, Somanathan Narayanasastri i Audisesha Reddy Kami Reddy. "Single step derivatization with CF3 enone of thiophene at ambient temperature to determine propellant grade hydrazines: a study by GC and GC-MS". Analyst 140, nr 1 (2015): 330–39. http://dx.doi.org/10.1039/c4an01648c.

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A simple, highly selective and rapid gas chromatography method (packed column with flame ionization detection) has been developed to determine hydrazine and monomethylhydrazine individually and for selective determination of hydrazine in the UH 25 mixture in organic medium.

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40

Bonczarowska, Marzena, Patryk Piątek i Sławomir Brzeźnicki. "Hydrazine. Determination in workplace air with high performance liquid chromatography – spectrophotometric technique". Podstawy i Metody Oceny Środowiska Pracy 35, nr 1(99) (25.03.2019): 45–57. http://dx.doi.org/10.5604/01.3001.0013.0804.

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Anhydrous hydrazine in room temperature is colorless fuming oily liquid with ammonia-like odor. It is used in various industries for electrolytic plating of metals on glass and plastics, as a chemical intermediate for the synthesis of pesticides, insecticides, medicines and days. It is used also as water treatment agent in energy industry (corrosion inhibitor), rocket propellant and as explosives material. Long term exposure to hydrazine may cause to skin irritation and allergic reactions. Diluted aqueous solutions of hydrazine may be irritating for skin, eye and respiratory tract. Epidemiologic studies shows that chronic exposure to hydrazine may cause cancer. In European Union hydrazine is classified as a carcinogenic substance (cat. 1B). Experts from International Agency for Research on Cancer (IARC) have classified hydrazine as a compound probably carcinogenic to humans (Group 2A). Due to decreasing of MAC value for hydrazine in Poland it was necessary to develop and validate a sensitive method for determining hydrazine concentrations in the workplace air in the range from 1/10 to 2 MAC values, in accordance with the requirements of Standard No. PN-EN 482. The study was performed using a liquid chromatograph with spectrophotometric detection. All chromatographic analysis were performed with Discovery LC-18 150 × 2,1 mm analytical column, which was eluted with mixture of acetonitrile and water (6:4 v/v). The method is based on the collection of hydrazine on glass fiber filter impregnated with sulfuric acid, extraction with mixture of sodium dihydrogen phosphate and EDTA, derivatization of extracted compound with benzaldehyde and chromatographic determination of resulted solution with HPLC technique. The method is linear (r = 0.9989) within the investigated working range 0.15–3.5 μg/ml (0.00125–0.029 mg/m3 for a 240-L air sample). Calculated limit of detection (LOD) and limit of quantification (LOQ) were 0.0007 μg/ml and 0.0023 μg/ml, respectively. The average extraction efficiency of hydrazine from filters was 97% and samples stored in refrigerator are stable for 14 days. The analytical method described in this paper enables determination of hydrazine in workplace air. The method is precise, accurate and it meets the criteria for procedures for measuring chemical agents listed in Standard No. PN-EN 482. The method can be used for assessing occupational exposure to hydrazine and associated risk to workers’ health. The developed method of determining hydrazine has been recorded as an analytical procedure (see appendix). This article discusses the problems of occupational safety and health, which are covered by health sciences and environmental engineering.

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Naumann, Clemens, Thomas Kick, Torsten Methling, Marina Braun-Unkhoff i Uwe Riedel. "ETHENE/NITROUS OXIDE MIXTURES AS GREEN PROPELLANT TO SUBSTITUTE HYDRAZINE: REACTION MECHANISM VALIDATION". International Journal of Energetic Materials and Chemical Propulsion 19, nr 1 (2020): 65–71. http://dx.doi.org/10.1615/intjenergeticmaterialschemprop.2020028133.

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Zhang, Youhong, Xinlong Chang i Wanlei Liu. "Corrosion Damage of Aluminum Alloy in Unsymmetric Uimethyl Hydrazine and Dinitrogen Tetroxide Liquid Propellant". MATEC Web of Conferences 67 (2016): 05021. http://dx.doi.org/10.1051/matecconf/20166705021.

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Carlotti, Stefania, i Filippo Maggi. "Evaluating New Liquid Storable Bipropellants: Safety and Performance Assessments". Aerospace 9, nr 10 (28.09.2022): 561. http://dx.doi.org/10.3390/aerospace9100561.

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Conventional storable bipropellants make use of hydrazine and its derivatives as fuels and nitrogen tetroxide as an oxidizer. In recent years, the toxicity character of these chemicals pushed the propulsion community towards “green” alternatives. Several candidates have been proposed among existing and newly developed chemicals, highlighting the need for a common and robust selection methodology. This paper aims at reviewing the most important selection criteria in the field of toxicity and discusses how to objectively define a green propellant, considering both the health and environmental hazards caused by the chemicals. Additionally, consistent figures of merit in the field of safety and handling operations and performance are proposed. In particular, operating temperatures, flammability and stability issues are discussed in the framework of physical hazards and storage requirements, while vacuum impulses, adiabatic flame temperature and sooting occurrence of the investigated couples are compared to the UDMH/NTO benchmark case. Hydrogen peroxide and nitrous oxide, and light hydrocarbons, alcohols and kerosene are selected from the open literature as promising green oxidizers and fuels, respectively. The identified methodology highlights merits and limitations of each chemical, as well as the fact that the identification of a universally best suited green couple is quite impractical. On the contrary, the characteristics of each propellant lead to a scenario of several “sub-optimal” couples, each of them opportunely fitting into a specific mission class.

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Fadela Benzenine, Chakib Seladji, Djamal Darfilal i Othman Bendermel. "Optimization of 10 N Monopropellant High Test Peroxide Thruster for Space Applications". Journal of Advanced Research in Fluid Mechanics and Thermal Sciences 100, nr 2 (31.12.2022): 60–77. http://dx.doi.org/10.37934/arfmts.100.2.6077.

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Monopropellant thruster is one of the most propulsion system types developed in the space industry. This system uses a single type of propellant that reacts in porous medium catalytic packed bed to generate thrust in the form of hot gases. The last decade, green propellant hydrogen peroxide (H2O2), also known as High Test Peroxide (HTP), thanks to its low cost and easy to store as liquid, is used as an alternative solution of hydrazine which is very toxic and not environmentally friendly. In the current study, hydrogen peroxide monopropellant thruster is investigated for application in the future satellites. A numerical simulation is performed using the Computational Fluid Dynamics (CFD) software ANSYS Fluent in order to simulate fluid flow of hydrogen peroxide in thruster, and the finite volume method was employed for resolving the governing equation. Species transport model is applied in the single-phase reaction simulation using the Eddy Dissipation model (EDM) for turbulence-chemistry interaction. A mathematical approach based on the local thermal non-equilibrium (LTNE) model is used to describe the heat transfer through solid and fluid phases in the packed bed consisting of identical spherical silver particles. Several simulations performed allowed an optimal design of the injector, catalyst bed length and diameter and nozzle geometry, to achieve a 10N monopropellant thruster with hydrogen peroxide at 87.5% concentration.

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Subramanian, Selvakumar, Somanathan Narayanasastri i Audisesha Reddy. "Kinetic Spectrophotometric Determination of Propellant Grade Hydrazines using Thiophenes with Active Carbonyl Groups". Defence Science Journal 64, nr 1 (23.01.2014): 33–40. http://dx.doi.org/10.14429/dsj.64.3092.

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Munjal, N. L., B. L. Gupta i Mohan Varma. "Preparative and mechanistic studies on unsymmetrical Dimethyl Hydrazine-Red Fuming Nitric Acid Liquid Propellant Gels". Propellants, Explosives, Pyrotechnics 10, nr 4 (sierpień 1985): 111–17. http://dx.doi.org/10.1002/prep.19850100406.

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Hu, Jie, Wei Li, De Yuan Li, Zhe Jun Zheng, Zhi Neng Ye i Bi Tian. "Eliminating Effects of Vitamin B₆ and Vitamin C on UDMH and Their Chemical Mechanism". Advanced Materials Research 347-353 (październik 2011): 344–48. http://dx.doi.org/10.4028/www.scientific.net/amr.347-353.344.

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Unsymmetrical dimethylhydrazine (UDMH) is a kind of cheap propellant for rocket luanching. But it is harmful to environment and human body. At present, the majority of UDMH eliminating agents are unsafe and inconvenient for use because of strong oxidizing property. The eliminating effects of vitamin B6, vitamin C and glacial acetic acid on UDMH are studied. 1mg vitamin B6 , 1mg vitamin C and 1mg glacial acetic acid is added into 10.00ml UDMH solution (1μg/ml) respectively, UDMH content is determined respectively in 30 minutes and 60 minutes through amino sodium ferrocyanide (TPF) spectrophotometry method at wavelength 500nm. The results show that vitamin B6 can eliminate 88% UDMH in 30 minutes. Vitamin C or acetic acid has no significant removal effect on UDMH. The chemical mechanism of vitamin B6 eliminating UDMH is that pyridoxal and pyridoxal 5 – phosphate monohydrate (PLP) can react with UDMH and generate hydrazone and water.

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48

Laue, Jörg, Gunther Seitz i Hans Waßmuth. "Synthese und [4+2]-Cycloadditionen von 4a, 8a-Methanophthalazin, das erste Propellan mit einem elektronenreichen und einem elektronenarmen 4π-Diensystem/Synthesis and [4+2] Cycloaddition Reactions of 4a, 8a-Methanophthalazine, the First Propellane with an Electronrich and an Electrondeficient 4π-Diene System". Zeitschrift für Naturforschung B 51, nr 3 (1.03.1996): 348–58. http://dx.doi.org/10.1515/znb-1996-0309.

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Abstract Cyclopropabenzene 3 reacts with 3,6-bis(trifluoro)-1,2,4,5-tetrazine 4 to afford in high yield the 4a,8a-methanophthalazine 6, the first propellane, containing an electron rich cyclohexadiene system on the one hand and an electron deficient diazadiene system on the other hand. According to the principle of Diels-Alder reactions with inverse electron demand, electron rich dienophiles like ketene acetals, enamines or dimethyl hydrazones react predominantly with the diazadiene system to yield the azo-bridged cycoadducts of type 19 and/or the tricyclic tetrahydropyridazines like 20. In the same fashion several more or less angle strained cycloalkenes cycloadd to the diazadiene of the propellane 6 to give the novel polycyclic azo compounds 34, 36, 38,40, 42 and 44 with exo-configuration of the annulated cycloalkanes. Attack apparently occurs from less hindered face anti to the methano bridge of 6 with high stereo-and site-selectivity. As anticipated the electron deficient dienophiles 1,2,4-triazoline-3,5-dione 45 and the benzoquinone 46 add with different site selectiviy to 6 furnishing the polycyclic pyridazines 47 and 48 resp. again by exclusive anti attack. Treatment of 6 with both an electron rich and an electron deficient dienophile like 49 and 45 resp. affords the heptacyclic anti-anti-bis adduct 51 with analogously high site-and stereoselectivity.

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49

Keshavarz, Mohammad Hossein, Alireza Ramadan, Ali Mousaviazar, Abbas Zali i Arash Shokrollahi. "Reducing Dangerous Effects of Unsymmetrical Dimethyl Hydrazine as a Liquid Propellant by Addition of Hydroxyethylhydrazine, Part II, Performance with Several Oxidizers". Journal of Energetic Materials 29, nr 3 (lipiec 2011): 228–40. http://dx.doi.org/10.1080/07370652.2010.514320.

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50

Dorrington, G. E. "Rationale and concept for a lunar pit reconnaissance probe". Aeronautical Journal 122, nr 1250 (19.01.2018): 666–91. http://dx.doi.org/10.1017/aer.2017.139.

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ABSTRACTSpeculation on near-term scientific reasons for the exploration of lunar pits is offered alongside comments on possible longer-term human exploitation. It is proposed that in order to determine whether or not one or more of the pits offer access the large subsurface voids e.g. a non-collapsed lava tube, a preliminary reconnaissance mission solely focused on obtaining lateral images (and/or LiDAR maps) is needed. Possible concept options for such a preliminary reconnaissance mission are discussed. It is suggested that one of the best possible strategies is to employ a micro-sized probe (~0.3 m) that would hop from a nearby main landing spacecraft to the selected pit. After the surface position of the main lander is determined accurately, the probe would perform a ballistic hop, or hover-traverse, a distance of ~3 km over the lunar surface using existing propulsive and guidance technology capability. Once hovering above the pit, the probe or a separate tethered imaging unit would then be lowered into the pit to acquire the necessary subsurface void topology data. This data would then be transmitted back to Earth, directly, via the lander, or via a store-and-forward orbiting relay. Preliminary estimates indicate that a probe of ~14 kg (dry mass) is viable using a conventional hydrazine monopropellant system with a propellant mass fraction of less than ~0.2 (20%) including margins, suggesting a piggyback architecture would be feasible.

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