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(BH)2B2H3BNH4 crystallizes in the orthorhombic Pnma space group. The structure is zero-dimensional and consists of eight azaniumylboron molecules, sixteen boranediylradical molecules, and eight diborane molecules.
(BH)6B3H5 crystallizes in the orthorhombic Pccn space group. The structure is zero-dimensional and consists of thirty-two boranediylradical molecules, eight diborane molecules, and eight B3H5 clusters. In each B3H5 cluster, there are three inequivalent B1- sites. In the first B1- site, B1- is bonded in a distorted water-like geometry to two H+0.82+ atoms. There is one shorter (1.19 Å) and one longer (1.33 Å) B–H bond length. In the second B1- site, B1- is bonded in a distorted water-like geometry to two H+0.82+ atoms. There is one shorter (1.19 Å) and one longer (1.33 Å) B–H bond length. In the third B1- site, B1- is bonded in a distorted trigonal non-coplanar geometry to three H+0.82+ atoms. There are a spread of B–H bond distances ranging from 1.19–1.35 Å. There are five inequivalent H+0.82+ sites. In the first H+0.82+ site, H+0.82+ is bonded in an L-shaped geometry to two B1- atoms. In the second H+0.82+ site, H+0.82+ is bonded in a single-bond geometry to one B1- atom. In the third H+0.82+ site, H+0.82+ is bonded in an L-shaped geometry to two B1- atoms. In the fourth H+0.82+ site, H+0.82+ is bonded in a single-bond geometry to one B1- atom. In the fifth H+0.82+ site, H+0.82+ is bonded in a single-bond geometry to one B1- atom.
Ni(BH)12(B2H3)4(C4N)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of twenty-four boranediylradical molecules, eight diborane molecules, two nickel molecules, and four C4N clusters. In each C4N cluster, there are four inequivalent C4- sites. In the first C4- site, C4- is bonded in a distorted single-bond geometry to one C4- and one N3- atom. The C–C bond length is 1.50 Å. The C–N bond length is 1.49 Å. In the second C4- site, C4- is bonded in a 1-coordinate geometry to one C4- and one N3- atom. The C–C bond length is 1.50 Å. The C–N bond length is 1.49 Å. In the third C4- site, C4- is bonded in a 1-coordinate geometry to one C4- and one N3- atom. The C–C bond length is 1.50 Å. The C–N bond length is 1.48 Å. In the fourth C4- site, C4- is bonded in a 3-coordinate geometry to three C4- atoms. N3- is bonded in a 3-coordinate geometry to three C4- atoms.
Thermostability and heat sink capacity of diborane, pentaborane, and ethyl decaborane fuels for jet aircraft
Reaction kinetics of high energy oxygen difluoride diborane propellant system
Improved injector for oxygen difluoride and diborane has better mixing characteristics and is able to project fuel onto the wall of the combustion chamber for better cooling. It produces an essentially conical, diverging, continuous sheet of propellant mixture formed by similarly shaped and continuously impinging sheets of fuel and oxidant.
Vacuum ignition characteristics of rocket engine using oxygen difluoride-diborane propellant
Oxygen difluoride-diborane propellant injector and chamber design criteria applied to unmanned spacecraft rocket engine development
Gelled space-storable oxygen difluoride and diborane analysis, including particle preparation, yield stresses, viscosities and storability
Growth of p-type semiconducting diamond by vapor phase deposition using methane-diborane doping gas mixture in presence of diamond seed crystals
Gas chromatographic determination of small quantities of inert gases in reactive propellants is discussed. Operating conditions used for specific analyses of helium in diborane and nitrogen in oxygen difluoride are presented in tabular form.
Simple, reliable ground-hold refrigeration system for common-bulkhead tank meets design criteria and objectives for ground-hold of oxygen difluoride and diborane. System is failsafe and malfunctions can be rectified without interruption of basic system functions.
An advanced design of an all metal, fast response, bipropellant, shut-off valve for use on long duration space missions is reported. The valve provides the flow control capability for a 1,000 lb thrust, bipropellant engine using oxygen difluoride and diborane as propellants. The shutoff seal selection is a soft-on-hard metal concept. The soft seal is a spherical shell that seats against a hard conical seat. Beryllium copper and beryllium nickel seals were selected to seal against an electrolyzed Inconel 718 seat. Poppet shaft sealing is achieved by use of hydroformed, Inconel 718 bellows. Two valve assemblies were fabricated and subjected to a series of tests including leak, response time, flow capacity, dry cycles, water cycles, liquid nitrogen cycles, liquid fluorine cycles, and lead-lag operation cycles. These tests demonstrated the ability of the valve to meet design goals.
A study was conducted of techniques having the capability of determining the performance and reliability of components for spacecraft liquid propulsion applications for long term missions. The study utilized two major approaches; improvement in the existing technology, and the evolution of new technology. The criteria established and methods evolved are applicable to valve components. Primary emphasis was placed on the propellants oxygen difluoride and diborane combination. The investigation included analysis, fabrication, and tests of experimental equipment to provide data and performance criteria.
Report discusses totally-automated oxidation and diffusion facility for fabricating IC's. Several innovations are demonstrated: process controller specifically designed for semiconductor processing; automatic loading system to accept wafers from air track, insert them in quartz carrier, and place carrier on paddle for insertion into furnace; automatic unloading of wafers back onto air track; and boron diffusion using diborane.
Ion beam deposition chambers used for carbon film generation were designed and constructed. Features of the developed equipment include: (1) carbon ion energies down to approx. 50 eV; (2) in suit surface monitoring with HEED; (3) provision for flooding the surface with ultraviolet radiation; (4) infrared laser heating of substrate; (5) residual gas monitoring; (6) provision for several source gases, including diborane for doping studies; and (7) growth from either hydrocarbon source gases or from carbon/argon arc sources. Various analytical techniques for characterization of from carbon/argon arc sources. Various analytical techniques for characterization of the ion deposited carbon films used to establish the nature of the chemical bonding and crystallographic structure of the films are discussed. These include: H2204/HN03 etch; resistance measurements; hardness tests; Fourier transform infrared spectroscopy; scanning auger microscopy; electron spectroscopy for chemical analysis; electron diffraction and energy dispersive X-ray analysis; electron energy loss spectroscopy; density measurements; secondary ion mass spectroscopy; high energy electron diffraction; and electron spin resonance. Results of the tests are summarized.
A totally automated facility for semiconductor oxidation and diffusion was developed using a state-of-the-art diffusion furnace and high temperature grown oxides. Major innovations include: (1) a process controller specifically for semiconductor processing; (2) an automatic loading system to accept wafers from an air track, insert them into a quartz carrier and then place the carrier on a paddle for insertion into the furnace; (3) automatic unloading of the wafers back onto the air track, and (4) boron diffusion using diborane with plus or minus 5 percent uniformity. Processes demonstrated include Wet and dry oxidation for general use and for gate oxide, boron diffusion, phosphorous diffusion, and sintering.
All beta-SiC films grown using on-axis (001) Si substrates that have been examined with transmission electron microscopy exhibit a high density of interfacial twins, stacking faults, and antiphase disorder. The antiphase boundaries can be decorated by chemical etching, sputter etching, wet oxidation, and beta-SiC growth in the presence of diborane. All traces of antiphase disorder are eliminated when the heteroepitaxial growth is carried out on vicinal (001) Si substrates that are tilted 2 deg about a 110-line axis. In addition, growth on the off-axis Si produces beta-SiC films that are significantly smoother than on-axis films. The density of stacking faults is apparently unaffected by growth on the off-axis substrates.