publicationDate stringlengths 10 10 | abstract stringlengths 0 37.3k | title stringlengths 1 5.74k | doi stringlengths 11 47 ⌀ |
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1984-01-01 | Compression-compression fatigue behavior of a glass fibercloth reinforcement epoxy composite at 300K and 77K is discussed in terms of the temperature (T) — cycles to failure (N) relationship, reliability, and damage initiation and growth. Some of the findings are as follows: the stress amplitude and number of cycles to failure are related to the temperature and characterized by a three-dimensional surface; Weibull parameters are sufficiently accurate to define the scatter in the fatigue results; failure by chance is the controlling degradation process; and fatigue damage consists of fairly uniform matrix crazing throughout the surface of the specimen. | Fatigue of Glass-Epoxy Composite at 77K and 300K: Observation and Prediction | 10.1007/978-1-4613-9868-4_3 |
1984-01-01 | To find the electrical resistivity of a metallic wire, one begins by measuring the potential difference V across a length of the wire L, when a current I is passed through it. According to Ohm’s Law, the ratio V/I is the electrical resistance R of the wire. In the general case, R is a tensor--that is, its value depends upon the direction of the current flow. However, most metals have cubic crystal structures for which R is isotropic, and non-cubic metals usually have simple enough crystal structures that the resistance tensor has only two or three independent terms. | Electrical Resistivity of Metals and Alloys at Cryogenic Temperatures: A Review | 10.1007/978-1-4613-9868-4_51 |
1984-01-01 | Taking advantage of the recent advances in electronics we have developed a resistance thermometry system for the cryogenic environment of Fermilab’s Energy Saver Accelerator that fits in a natural way with its microcomputer based control logic. The system is based on measuring the voltage across a sensing resistor immersed in the cryogenic fluid while a current of 2.5 mA flows through it. High level signals (0.05 to 0.25 V) allows the use of integrated circuit multiplexers and reduces the relevance of thermal emf corrections. In order to prevent excessive self-heating of the sensor the current is kept on for a very short time (50 μs), just enough for it to stabilize. Near the end of the current pulse the voltage is sampled and held for an analog to digital conversion followed by storage in memory. The total operation is carried out in 100 μs. The repetition rate, 1 Hz, allows time for the sensing resistor to come again into thermal equilibrium with the surrounding fluid. | Pulsed Current Resistance Thermometry | 10.1007/978-1-4613-9865-3_99 |
1984-01-01 | The Infrared Astronomical Satellite (IRAS) is the first space telescope to perform observations in the far infrared from orbit. IRAS was launched from Vandenberg Air Force Base on January 25, 1983 into a 900 km orbit. The satellite is surveying the entire sky in four bands covering the wavelengths from 8 to 120 micrometers. The satellite performance is excellent. With 25% of the data reduced, 262,000 point sources and 80,000 extended sources have been detected.^1 IRAS has the first large superfluid helium dewar in space and is expected to last approximately 345 days. | IRAS Cryogenic System Flight Performance Report | 10.1007/978-1-4613-9865-3_74 |
1984-01-01 | Material science plays the leading role in modern cryogenic engineering. Fabrication of new types of structures requires the use of steels and alloys possessing high strength under various loading conditions. | Progress in Cryostructural Materials and their Welding in the USSR | 10.1007/978-1-4613-9868-4_33 |
1984-01-01 | The 1000 MVA Superconducting Power Transmission Cable Test Facility at Brookhaven National Laboratory is the world’s highest power demonstration of the application of superconductivity to electric utility engineering. The major purpose of the facility is to evaluate and demonstrate the performance of flexible cables, the cable enclosure and cable terminations under realistic simultaneous voltage and current excitation corresponding to a 138 kV system with a three-phase rating of 1000 MVA. In addition, massive supporting equipment is required at the site in order to cool and excite the cables. This equipment includes: 1) A 700 W supercritical helium refrigerator. 2) A 100 W refrigerator for lead cooling (CTI model 1430). 3) 60 Hz excitation supplies with maximum ratings up to 6000 A and 240 kV to ground. 4) 1000 kV Marx generator for impulse and surge voltage tests. 5) An extensive and ever-expanding computer system for data collection and logging and system control. 6) Several overlays of vacuum pumping and piping, pneumatic pumps and controls and large oil and water circulating and cooling systems. | Cryo-Electric Testing of a 1000 MVA Superconducting Power Transmission System | 10.1007/978-1-4613-9865-3_13 |
1984-01-01 | Currently the most economical method for long distance intercontinental movement of natural gas is liquefaction and transportation by sea. Using this mode there is always the possibility that a liquefied-gas carrier could get into difficulties, and as part of the contingency for this situation, Shell Research Limited has developed an LNG floating emergency transfer hose. In this paper we shall demonstrate how the technical requirements for the hose have led to a practical piece of hardware. | The Analysis and Development of a Floating LNG Emergency Transfer Hose | 10.1007/978-1-4613-9865-3_96 |
1984-01-01 | In many of the studies previously reported, high pressure vapor-liquid equilibria have been calculated by applying equations of state. The method for calculating the vapor-liquid equilibria using two-parameter cubic equations of state is simple and widely applied in practice^1–3. To predict high pressure vapor-liquid equilibria using two-parameter cubic equations of state, namely, P = f(v, T, a, b), it is necessary to know the mixture energy parameter, a, and mixture size parameter, b. Conventionally, parameters a and b for the mixture have been evaluated by the following mixing rules: (1) % MathType!MTEF!2!1!+- % feaagaart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaaeaaaaaaaaa8 % qacaWGHbGaeyypa0Zaaabua8aabaWdbmaaqafapaqaa8qacaWG4bWd % amaaBaaaleaapeGaamyAaaWdaeqaaOWdbiaadIhapaWaaSbaaSqaa8 % qacaWGQbaapaqabaGcpeGaamyya8aadaWgaaWcbaWdbiaadMgacaWG % QbaapaqabaaabaWdbiaadQgaaeqaniabggHiLdaal8aabaWdbiaadM % gaaeqaniabggHiLdaaaa!465A! $$a = \sum\limits_i {\sum\limits_j {x_i x_j a_{ij} } }$$ (2) % MathType!MTEF!2!1!+- % feaagaart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaaeaaaaaaaaa8 % qacaWGHbWdamaaBaaaleaapeGaamyAaiaadQgaa8aabeaak8qacqGH % 9aqpcaGGOaGaaGymaiabgkHiTiaad2gapaWaaSbaaSqaa8qacaWGPb % GaamOAaaWdaeqaaOWdbiaacMcacaGGOaGaamyya8aadaWgaaWcbaWd % biaadMgacaWGPbaapaqabaGcpeGaamyya8aadaWgaaWcbaWdbiaadQ % gacaWGQbaapaqabaGcpeGaaiyka8aadaahaaWcbeqaa8qacaaIWaGa % aiOlaiaaiwdaaaaaaa!4ACC! $$a_{ij} = (1 - m_{ij} )(a_{ii} a_{jj} )^{0.5}$$ (3) % MathType!MTEF!2!1!+- % feaagaart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaaeaaaaaaaaa8 % qacaWGIbGaeyypa0Zaaabua8aabaWdbiaadIhapaWaaSbaaSqaa8qa % caWGPbaapaqabaGcpeGaamOya8aadaWgaaWcbaWdbiaadMgaa8aabe % aaaeaapeGaamyAaaqab0GaeyyeIuoaaaa!3FBD! $$b = \sum\limits_i {x_i b_i }$$ The interaction coefficient, m_ij, in Eq. (2) must be determined with experimental vapor-liquid equilibrium data for each system and temperature studied. Vapor-liquid equilibria can then be calculated by using these mij and component parameters, a_ii, b_i. In this study, the mixture energy parameter is determined by using a_ii, b_i and the chemical formulas for the components. | Prediction of High Pressure Vapor-Liquid Equilibria with a Mixing Rule Using the Asog Group Contribution Method | 10.1007/978-1-4613-9865-3_112 |
1984-01-01 | The trend toward the use of higher field superconducting magnets is creating the need for strong, tough structural materials to restrain the high magnetic forces. Austenitic and high-N austenitic stainless steels are considered for such uses because of their high strength and good toughness, combined with high Young’s modulus and low thermal conductivity. Study of the temperature dependence of tensile flow strength leads to better understanding of deformation mechanisms in these face-centered cubic, polycrystalline alloys. | The Temperature Dependence of the Tensile Yield Strength of Selected Austenitic Steels | 10.1007/978-1-4613-9868-4_32 |
1984-01-01 | A substantial effort at KMS Fusion is in the area of Direct Illumination Spherical Target Experiments with the recent emphasis in understanding thermal and superthermal transport and the mechanisms which can limit high convergence ratio implosions. These processes must be well understood in order to do effective target design calculations needed for larger ICF facilities. | Direct Illumination Spherical Target Experiments | 10.1007/978-1-4615-7332-6_44 |
1984-01-01 | Structural materials for large superconducting magnets of the next tokamak fusion reactors should have high yield strength with sufficient toughness at cryogenic temperatures. According to Japan Atomic Energy Research Institute^1 for example, the yield strength and the fracture toughness required are specified to be more than 1200 MPa and 200 % MathType!MTEF!2!1!+- % feaagCart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaaeaaaaaaaaa8 % qacaqGnbGaaeiuaiaabggadaGcaaWdaeaapeGaaeyBaaWcbeaaaaa!39C5! $$ {\text{MPa}}\sqrt {\text{m}} $$ at 4 K, respectively. The present work has investigated the effects of several metallurgical factors on mechanical properties of 32% Mn steels at cryogenic temperatures in order to obtain basic suggestions for developments of new high strength steels with high toughness for cryogenic uses. The 32% Mn steels have been examined in as-solution treated and aged conditions. The latter condition simulates the heat treatment for the precipitation of intermetallic compound Nb_3Sn. Structures used to support winding in the Wind and React method^2,3, or conductor sheaths will be heated together with the reacting materials, and it is demanded that the decrease in their strength and toughness during the heat treatment should be as small as possible. | Mechanical Properties of High Yield Strength High Manganese Steels at Cryogenic Temperatures | 10.1007/978-1-4613-9868-4_19 |
1984-01-01 | The testing of the properties of packed-partiele beds and regenerators at cryogenic temperatures as low as 4 K is an essential part of the magnetic refrigeration research and development program at the Los Alamos National Laboratory. We envision magnetic refrigeration and heat pump systems operating in various ranges from 4 K to ambient temperature and above. Only pressurized helium gas appears suitable as the heat exchange fluid for the low-temperature applications. Because published data on the properties of porous beds at low temperatures is sparse, we have found it necessary to develop an experimental test apparatus to study the properties of various configurations of beds and regenerators. Two of the well-known methods for such studies are the steady-enthalpy-flux method^1 and the single-blow transient method.^2 We have developed an experimental system in which gas flow can be suddenly switched to an alternate hotter (or colder) flow in step-function fashion at temperatures from 4 to 300 K. This apparatus will yield information on steady-state heat transfer and friction factors as well as on the transient behavior. Such information is very important to the design of high-efficiency magnetic refrigeration systems. | Experiment to Determine Properties of Packed Particle Beds and Regenerators at Cryogenic Temperatures | 10.1007/978-1-4613-9865-3_69 |
1984-01-01 | During the last eight years there has been enormous upsurge of interest in these materials and it is perhaps an appropriate moment to speculate as to their possible applications in cryogenic engineering. | Metallic Glasses | 10.1007/978-1-4613-9868-4_48 |
1984-01-01 | Enthalpy values for pure components and mixtures are important in process design calculations. This study concerns the calculation of excess enthalpies, H^E, for binary gaseous mixtures of cryogenic interest by means of an equation of state. Since excess properties are usually very sensitive to the variation of mole fractions of the constituent components, their values calculated from an equation of state are sensitive to the mixing rules used for the equation parameters. The purpose of this study is to select a suitable equation from a number of cubic equations containing two to four parameters with appropriate mixing rules for the desired calculation. | Calculation of Excess Enthalpies of Mixing for Binary Gaseous Mixtures | 10.1007/978-1-4613-9865-3_110 |
1984-01-01 | Storage | 10.1007/978-94-009-5634-6_11 | |
1984-01-01 | The importance of thermophysical properties data for fluids involved in cryogenic processing is generally recognized within the engineering community. Cryogenic fluid properties have played significant roles in the development of technologies in such areas as follow: aerospace program, air separation plants, liquefied natural and petroleum gases, fuels, food freezing, ethylene production, ethane recovery, natural gas processing, health and medicine, chemical process plants, and electric power generating systems. With the spiraling inflation in the costs of energy, materials, feedstocks, labor, and environmental compliance and with the increase in capacity of individual plants, there has been a growing awareness of the importance of the accuracy of the thermophysical properties data for fluids in process design and operation. Recently there have been numerous studies^1–13 published on the importance of thermophysical properties data of fluids, and many of the examples cited deal with cryogenic systems.^1–7 The economic impact of uncertainties in fluid properties data has been presented in many of these papers.^1–7 | Status of Thermophysical Properties Data for Pure Fluids and Mixtures of Cryogenic Interest | 10.1007/978-1-4613-9865-3_104 |
1984-01-01 | The SN-transition, measured resistively on Nb_3Ge films, often exhibits a rather broad interval ∆T_C between onset and fully superconducting state. Measurements with variable separation d of the voltage probes down to 1 mm showed^1, that large scale inhomogeneities of the material are at least in part responsible for this effect. On the other hand, if the individual grains of the films themselves have a sharp transition, one would expect a drastic reduction of ΔT_C when d is reduced to the dimensions of crystallites. In this paper we report measurements, performed with probe separations d down to the µm range. With an in-situ technique this was achieved using a piezoelectric micromanipulator for probe positioning in a scanning electron microscope (SEM) for visual position control. The measurements were carried out on dc sputter deposited films and on specimens prepared by CVD. The investigated sample volume could be further reduced using photolithography and reactive plasma etching. | Local Investigation of Superconducting Transition of Nb_3Ge Films | 10.1007/978-1-4613-9868-4_71 |
1983-12-01 | Intensity of heat transfer in thermostatic control of cryogenic equipment with supercritical helium | 10.1007/BF01149002 | |
1983-12-01 | Stiffness of composite rods based on boron-reinforced plastic at room and cryogenic temperatures | 10.1007/BF01523167 | |
1983-12-01 | An estimate of fracture toughness of crosslinked polybutadiene rubber at — 180° C has been made using the double torsion method. By using suitable specimen dimensions and strain rates, controlled crack propagation can be achieved, together with a constant compliance to crack length ratio. Strain energy release rates for this polymer, crosslinked with either dicumyl peroxide or sulphur, were found to be an order of magnitude higher than for linear, glassy thermoplastics. Crazing is considered to contribute to the high toughness observed. | Fracture toughness of polybutadiene at cryogenic temperatures | 10.1007/BF00540750 |
1983-11-01 | Arrays of six superconducting tunnel junctions have been used in a heterodyne receiver over the frequency range 35–50 GHz. The mixer array and a 3.7–4.2 GHz parametric amplifier used as the if amplifier are immersed in liquid helium and operated at 2 K. The high if allows single sideband operation with a system noise temperature varying rather smoothly from 220 K at 35 GHz to 140 K at 50 GHz. Mixer noise temperatures between 11 and 21 K were measured over the band indicating that the use of arrays to enhance the dynamic range does not seriously affect the mixer noise performance in this frequency range. The receiver is used for radio astronomical observations in the Onsala 20 m telescope in Sweden. | A low noise SIS array receiver for radioastronomical applications in the 35–50 GHz band | 10.1007/BF01009311 |
1983-08-01 | The most important operating parameters of a commercial purge and trap GC apparatus have been investigated. Band broadening problems arising from the slow desorption of compounds from the Tenax trap have been overcome by cryogenic focussing at the beginning of the column. Good results have been obtained with both packed and capillary columns. The sensitivity of the technique is sufficient to detect benzene in water at concentrations below 1μg kg^−1 (1 ppb). | A study of some of the parameters in purge and trap gas chromatography | 10.1007/BF02262922 |
1983-07-01 | The size of a conical cavity characterizing the start of boiling is estimated on the basis of analyzing the stability of a nucleus of vapor in such a cavity. | Conditions for boiling start in cryogenic liquids | 10.1007/BF00845440 |
1983-04-01 | Combined action of microwave irradiation and local cooling on living tissues | 10.1007/BF00838879 | |
1983-01-01 | Cryogenics began in 1877 when L. Kalete observed the transition of oxygen from the gaseous to the liquid state. Small systems for liquefaction of air were developed by Linde and Hampson in 1895, working independently, but the broad development of cryocoolers came much later and especially after World War II. | Cryogenic Engineering and Cryocooler Development in the USSR | 10.1007/978-1-4684-4430-8_6 |
1983-01-01 | Metrological evaluation of the conversion characteristics of turbine flowmeters working with cryogenic liquids | 10.1007/BF00827572 | |
1983-01-01 | In the field of high-energy physics, large-scale high-energy particle accelerators are either under construction or planning, where the “Wind-and-React” process is possibly applied to employ Nb_3Sn superconductor instead of NbTi for the production of over five-tesla-class superconducting magnet. This process necessitates the structural materials with favored properties at cryogenic temperatures before and after Nb_3Sn precipitation heat treatment. The present study is carried out to examine the magnetic and mechanical properties of a variety of austenitic stainless steels and high manganese steel which are both considered as candidate structural materials for superconducting magnet attached to high energy particle accelerator and other superconducting applied technologies. In particular attention is paid to the effect of a specified heat treatment for the precipitation of intermetallic compound Nb_3Sn to be used as superconductor on the properties such as ductility and toughness as well as serength at lower temperatures. | Cryogenic Properties of Austenitic Stainless Steels for Superconducting Magnet | 10.1007/978-1-4613-3730-0_7 |
1983-01-01 | The extensive use of austenitic Fe-Cr-Ni alloys in cryogenic engineering and space investigations necessitates the study of the strength and plastic properties of these materials at low temperatures. One of the most important properties of metastable stainless Fe-Cr-Ni alloys is the martensitic transformation, which occurs in them at low temperatures and during deformation. During this process, the initial fcc (y) austenite rearranges into paramagnetic hcp (E) martensite and ferromagnetic bcc (a) martensite. Whether martensitic transformation or another process is dominant depends on the chemical composition, temperature, and degree of deformation of the alloy. | The Influence of Martensitic Transformation on Strength and Plasticity of Fe-Cr-Ni Alloy Single Crystals | 10.1007/978-1-4613-3730-0_4 |
1983-01-01 | The austenitic stainless steels are Fe-Cr alloys with sufficient nickel and manganese (and sometimes nitrogen) to stabilize austenite, a face-centered cubic (f.c.c.) phase. Chromium provides corrosion resistance. The most typical austenitic stainless steels are variations of the 18Cr-9Ni alloy. Although none of the commercial alloys were specifically developed for low-temperature service, several of them have been widely used in a variety of cryogenic applications. Their popularity stems from their retention of excellent mechanical properties, particularly toughness, at low temperatures coupled with ready availability, ease of fabrication, and good service experience. Their disadvantages are they are more expensive and have lower yield strength than ferritic Fe-Ni steels and aluminum alloys, and their machinability is poorer than that of aluminum alloys. | The Properties of Austenitic Stainless Steel at Cryogenic Temperatures | 10.1007/978-1-4613-3730-0_1 |
1983-01-01 | Standards for the stress analysis of thin-walled shell structures in cryogenic engineering | 10.1007/BF01523419 | |
1982-12-01 | Short-term strength of boron plastic-reinforced tubular samples under room and cryogenic temperature conditions | 10.1007/BF00768652 | |
1982-09-01 | New cryogenic alloys: The Fe−Mn−Al system | 10.1007/BF02892364 | |
1982-09-01 | An investigation was undertaken to examine the effects of nine different growth regulators on growth in vitro of shoot cultures of the semi-dwarfing cherry rootstock Colt ( Prunus avium × P. pseudocerasus ). The effects of each supplement on shoot extension and proliferation and also leaf and callus production were noted, and it was found that BAP has the ability to proliferate shoots, IBA nullifies this effect and that kinetin, ABA, GA_3 and ethylene inhibit the growth of colt cultures. Conditions were established which resulted in a) optimum shoot growth prior to subsequent rooting or grafting; b) maximum shoot proliferation for rapid clonal multiplication and c) minimum shoot growth. This study will form the basis of an investigation into germplasm conservation of temperate fruit trees by both cryogenic storage and minimal growth techniques. | Effect of various growth regulators on growth in vitro of cherry shoot tips | 10.1007/BF00037000 |
1982-08-01 | A one-dimensional model is used to calculate the parameters of a two-phase flow and generalize test data on discharge coefficients. | Study of the drag of a throttle in the film boiling of a cryogenic liquid flowing in a horizontal pipe | 10.1007/BF00825006 |
1982-08-01 | Criteria are obtained for the ambiguity of HDC of boiling channels which allow for local inlet and outlet drag. Results of calculations presented for the most commonly used cryogens indicate the possible ambiguity of the HDC. | Ambiguity of the hydrodynamic characteristics (HDC) of boiling channels in cryogenic units | 10.1007/BF00825007 |
1982-06-01 | A procedure for prolonged cryogenic storage of periwinkle cell cultures is described. Cells derived from periwinkle, Catharanthus roseus (L.) G. Don, and subcultured as suspension in 1-B5C nutrient medium have been frozen, stored in liquid nitrogen (−196°C) for 11 weeks, thawed and recultured. Maximal survival was achieved when 3–4 day-old cells precultured for 24 h in nutrient medium with 5% DMSO were frozen at slow cooling rates of 0.5 or 1°C/min prior to storage in liquid nitrogen. The only loss in viability of cells occurred subsequent to treatment with DMSO. Abbreviations: DMSO, dimethylsulfoxide; 2,4-D, 2,4-dichlorophenoxyacetic acid; TTC, triphenyltetrazolium chloride. | Cryopreservation of periwinkle, Catharanthus roseus cells cultured in vitro | 10.1007/BF00269181 |
1982-05-01 | The process of chilling parallel cryogenic pipes by a uniflow stream is analyzed with heat transfer between them taken into account. | Peculiarities of chilling an array of parallel cryogenic pipes | 10.1007/BF00824935 |
1982-04-01 | Monte Carlo calculations have been performed to obtain estimates of the background gas pressure and molecular number density as a function of position in the PDX-prototype neutral beam injector, which has undergone testing at the Oak Ridge National Laboratory. Estimates of these quantities together with the transient and steady-state energy deposition and molecular capture rates on the cryopanels of the cryocondensation pumps and the molecular escape rate from the injector were obtained utilizing a detailed geometric model of the neutral beam injector. The molecular flow calculations were performed using an existing Monte Carlo radiation transport code, which was modified slightly to monitor the energy of the background gas molecules. The credibility of these calculations is demonstrated by the excellent agreement between the calculated and experimentally measured background gas pressure in front of the beamline calorimeter located in the downstream drift region of the injector. The usefulness of the calculational method as a design tool is illustrated by a comparison of the integrated beamline molecular density over the drift region of the injector for three modes of cryopump operation. | Monte Carlo simulation of molecular flow in a neutral beam injector and comparison with experiment | 10.1007/BF01054582 |
1982-01-01 | The applied forces to the component materials of a superconducting magnet turn to varied and complex form accompanied with increase in magnet size and/or pulsative mode of operation. These materials are required to withstand the varied forces and show sufficient performance at cryogenic temperatures. It is important, therefore, to elucidate the behavior of each magnet component against the various forces at low temperatures. | Impact Tests of Reinforced Plastics at Low Temperatures | 10.1007/978-1-4613-3542-9_25 |
1982-01-01 | National Bureau of Standards personnel are continuing to work with magnet fabricators and with representatives of the U.S. laminating industry to establish standard grades of nonmetallic insulator and structural support materials for use in critical parts of magnetic fusion energy (MFE) cryogenic systems. Standardized materials are required for several reasons: (1) excessive variability in the 4-K mechanical properties among nonmetallic laminates purchased to present industrial generic designations, (2) the impracticality of establishing performance specifications for retention of properties after neutron and gamma irradiation at 4 K, and (3) lack of knowledge of the significant elements in a laminate that determine such performance. | Current Status of Standardized Nonmetallic Cryogenic Laminates | 10.1007/978-1-4613-3542-9_26 |
1982-01-01 | The ultimate strength and yield strength of the majority of steels and alloys at cryogenic temperatures increase with a decrease in temperature. This is characteristic mainly of the widely used austenitic, ferritic, and martensitic steels. The design of vessels for storage of cryogenic liquids is erroneously based on strength characteristics of metal at room temperature. Sometimes faulty design is the result of improper test methods, but more often it is the result of insufficient data on the capacity of real structures, their strength margin, and safety. During the last few years, investigations in various countries in the field of cryogenic materials have made the application of the low-temperature strength in design more reasonable. By increasing the design values of allowable stresses, fewer materials and cryogenic liquids are needed in service, and, therefore, expenses are reduced. | The Use of Low-Temperature Strengthening of Steels in Welded Cryogenic Structural Codes | 10.1007/978-1-4613-3542-9_14 |
1982-01-01 | Possibility of increasing the working pressure in cryogenic vessels | 10.1007/BF01179052 | |
1982-01-01 | Thomas and King^1 reported in 1975 that the presence in polyethylene of certain antioxidants of the substituted phenol type caused a dielectric relaxation at 4.2 K. Although peak loss factor occurred at several kHz, the loss enhancement at 50–60 Hz was significant in view of the possible use of polyethylene tapes for the insulation of a superconducting power transmission line. It has now been found that all antioxidants that are derivatives of 2,6 di-tert-butyl phenol (“DBF” - see figure 1) cause such a relaxation, but that any other phenol or non-phenol antioxidant may be used without causing significant loss enhancement at cryogenic temperatures.^2 DBF and its derivatives cause similar relaxations when added to polyethylene, polypropylene or other polyolefins, or dissolved in paraffin or decalin.^3 By an appropriate isotopic substitution it has been demonstrated that the effect is due to the hindered rotation of the hydroxyl groups of the molecules,^4 so in fact it is now clear that Thomas and King rediscovered at cryogenic temperatures a dielectric relaxation which had been known since 1957. Davies and Meakins^5 then reported that a solution of 2, 4, 6 tri-tert-butyl phenol in decalin had two resolved relaxations, and were able to identify the faster one (30 GHz loss peak at ambient temperature) with hydroxyl group rotations and the slower one with rotations of entire molecules. | Dielectric Loss Due to Antioxidants in Polyolefins | 10.1007/978-1-4613-3365-4_8 |
1982-01-01 | During 1977 and early 1978 Horizon Exploration Ltd, (formerly S & E Geophysical Ltd.) carried out a project to evaluate the effectiveness of a new marine seismic energy source. The new source known as a “water gun” was compared with the results obtained from the conventional “air gun” energy source. | 3rd Round Projects | 10.1007/978-94-009-7371-8_3 |
1982-01-01 | The technology of composite materials is presently at the state that metals technology was before being systematized by the establishment of industry standards. It is difficult to imagine working in metals technology in the United States without the ability to associate performance with designations such as 304L for stainless steel or 2024-T4 for aluminium. It would be equally difficult for individuals in other countries to perform effectively without similar national metal and alloy coding systems that transcend proprietary designations, but this is the situation presently confronting those working in the composite materials area, in the United States and elsewhere. | Standardizing Nonmetallic Composite Materials for Cryogenic Applications | 10.1007/978-1-4613-3365-4_22 |
1982-01-01 | After the thorough representation of the theoretical fundamentals of parametric circuits, we shall now give a short survey of the various fields of practical applications. With respect to current developments, we shall confine ourselves to examples of amplifiers and converters which have been developed and built during the last few years, and discuss their technical peculiarities as well as their advantages and drawbacks. Moreover, we will briefly mention some promising concepts which are still being tried out experimentally. Among these systems, the parametric amplifier (paramp) is of dominant importance; for this reason we shall dedicate the largest scope in the subsequent considerations to it. | Applications of Parametric Circuits | 10.1007/978-3-642-67937-7_9 |
1982-01-01 | The reaction of a composite system to a service load is a complex function of the physical and mechanical properties of its components (matrix and reinforcement); the relative directionality of the applied loads versus the geometry of the reinforcement (anisotropy effect); the magnitude of the applied loads, and the rate at which they are introduced (viscoelasticity effect). Although all these parameters may not be important in a particular design with a selected reinforcement and simple loading, understanding that these effects exist and being prepared to include them in design criteria is critical for developing cost-effective high performance composite parts. As composite systems are introduced as secondary and primary structures for cryogenic applications, characterization of the interaction of stress and low temperatures on the performance of these systems is also necessary. | Characterization of Glass-Reinforced Composites for Cryogenic Applications | 10.1007/978-1-4613-3542-9_20 |
1982-01-01 | The reasons why the expected performance of superconducting magnets is not easily achieved are because of instabilities such as training and degradation. Impregnation or potting techniques have been employed in order to modify such instabilities. Epoxide resin has been selected in this work from the range of impregnating materials (eg woods metal,^1 epoxy^2 ^5 and wax^6) because epoxide resins have been shown to possess excellent adhesive strength and satisfactory mechanical properties at cryogenic temperatures. | Lap Test of Epoxide Resin at Cryogenic Temperatures | 10.1007/978-1-4613-3365-4_11 |
1982-01-01 | Advanced structural composites reinforced with boron, graphite, or aramid fibers have unique mechanical, thermal, and electrical properties that make them attractive alternatives for metals in many cryogenic applications. A most promising application is the structure of the central solenoid of the poloidal field system in Tokamak magnetic fusion energy (MFE) devices.^1 Depending on the flux rise time of a particular design, energy loss due to generation of eddy currents in metallic structures might place an excessive burden on the refrigeration system. Here, a replacement of the metallic structure with advanced composites could suppress eddy currents while providing strength and stiffness equal to that, of steel. The low thermal conductivity of graphite-reinforced epoxy laminates in the 77–4 K range combined with high strength and modulus suggests the possibility of fabricating more efficient thermal isolation supports than heretofore available. | Mechanical Performance of Graphite- and Aramid-Reinforced Composites at Cryogenic Temperatures | 10.1007/978-1-4613-3542-9_16 |
1982-01-01 | A superconductive energy storage magnet requires a large quantity of low-thermal-conductive, high-load-carrying supporting structures to carry the radial and axial compressive loads from the 1.8 K magnet coils to room temperature bedrock.^1–3 Engineering data is needed on low cost commercial composites for struts to be used in the superconductive energy storage magnet designs at the University of Wisconsin-Madison. The main properties are compressive strengths, delamination strengths, shear properties and compressive fatigue properties at cryogenic temperatures and room temperatures.^4–7 | The Strain Energy Release Rate of a Glass Fibre Reinforced Polyester Composite | 10.1007/978-1-4613-3365-4_15 |
1982-01-01 | This paper presents two contributions to the development of the in situ process for production of high-field Nb_3Sn-Cu supercoducting wire. First, in the utilization of multidie drawing equipment for reduction of Cu-Nb alloy castings to wire size, even though the alloy is quite ductile, it is desirable to utilize some intermediate anneals to insure zero breakage.^1 It is shown here that these anneals can be controlled to improve the J_c properties of the wire. Second, a technique is presented for the production of a cryostabilized in situ wire that is compatible with large-scale production methods. The technique utilizes a combination of rolling and extrusion to produce wire with a stabilizing Cu core. | Development of Cryostabilized Nb_3Sn-Cu Superconducting Wire Using the In Situ Process | 10.1007/978-1-4613-3542-9_52 |
1982-01-01 | The design of large, 6-m diameter, composite aluminum-fiber- glass epoxy pressure vessels for the transportation of liquefied natural gas (LNG) at intermediate temperature is presented. The pressure vessels are designed to have an operating pressure range of up to 6.21 MPa (900 psi) and pressure-to-burst ratio close to two. The cylindrical pressure vessels are circumferentially reinforced with layers of high strength fiberglass epoxy or pultruded glass polyester overwrap. The vessels are prestressed at ambient temperature, using a sizing technique (autofrettage). The large pressure vessels are to be used in the economical storage or transport of LNG at temperature and pressure conditions between the critical conditions, 191 K, 4.69 MPa (−116°F, 680 psi) and atmospheric conditions, 106 K, 0.1 MPa (−268°F, 14.7 psi). The pressure vessels are designed for ultimate failure modes in the circumferential direction to prevent the possibility of an axial separation of a portion of the vessel at failure. | Composite Aluminum-Fiberglass Epoxy Pressure Vessels for Transportation of LNG at Intermediate Temperature | 10.1007/978-1-4613-3542-9_91 |
1982-01-01 | It is commonly observed that bronze-processed Nb_3Sn composites (internal diffusion, external diffusion, or in situ ) have a super-conducting critical temperature (T_C) that rises as reaction time increases at any reaction temperature until a maximum value is finally reached. This has been explained by some as a reduction in the stress, which produces a degradation of the T_C of Nb_3Sn layers,^1, 2, 3 or, in a slightly different system, as a proximity effect of the unreacted Nb core on the Nb_3Sn.^4 We have studied two 13 wt.% Sn bronze tape composites (bronze:superconductor ~ 3:1) and found that the intrinsic T_C (i.e., without bronze) is more a function of layer thickness than reaction time. We have compared our data to that of other workers and have found a common plot of T_C versus layer thickness for diffusion-grown Nb_3Sn. Our Auger electron spectroscopy (AES) studies show that this behavior can be explained by the composition gradients existing in the diffused layers and that impurity concentrations within the layer and particularly reaction temperature also affect T_C but are found to be secondary in their effect. The common plot of T_C versus layer thickness is valid only for layers where the reaction is still proceeding, that is, for layers that have a considerable core of unreacted Nb. | The Layer Thickness Dependence of the Transition Temperature in Niobium-Tin | 10.1007/978-1-4613-3542-9_40 |
1982-01-01 | The many modern large-scale applications of cryogenics, from superconducting magnets for fusion research to LNG tankers, have been supported by materials that were usually adequate for the task and that appeared usually just in time. This is, of course, not accidental. It is probably fair to say that all significant progress in cryogenic applications has, in one way or another, come about because of an advance in materials or a clever new use of existing materials. As an example, consider the Collins helium liquefier, recently described as “the single most important technical advance of the past forty years in cryogenics.”^1 The basic concept of the expansion engine liquefier had been developed quite a few years earlier by Kapitza.^2 Collins’s technical improvements that led to production of a successful machine were in large part the clever use of materials, including:^3 hard nitrided steel for pistons and cylinders that allowed smaller clearance and, thus, less leakage; a new design for an efficient heat exchanger using copper fins in copper nickel tubing; and keeping piston and valve rods always in tension, thus allowing use of thinner rods resulting in reduced thermal losses. | Low-Temperature Materials Research: A Historical Perspective | 10.1007/978-1-4613-3542-9_1 |
1982-01-01 | In an associated paper,^1 cryogenic fatigue fracture of glass-fiber-reinforced composites subjected to in-phase, biaxial cyclic stresses has been studied. Both the fatigue fracture life and associated failure mechanisms in the composites have been examined. It has been discussed^2 that in many cryogenic engineering applications of fiber-reinforced composites, the consideration of fatigue fracture alone is not adequate for a reliable design and that other parameters measuring progressive fatigue damage in the material may be needed also. Since many cryogenic composite devices and structures, which are usually under a complex pulsating state of electromagnetic and mechanical stresses, are designed on the basis of stiffness and/or stability considerations, naturally, degradation of stiffness or modulus of the composite material subjected to a complex state of cyclic stress is of critical importance. Furthermore, stringent requirements of maintaining a proper cryogenic temperature level to achieve optimum performance (for example, superconductivity) led to the consideration of hysteresis energy dissipation or internal damping in the material during cyclic loading. | Degradation of Fiber-Reinforced Composite Materials at Cryogenic Temperatures, Part II—Multiaxial Fatigue | 10.1007/978-1-4613-3542-9_19 |
1982-01-01 | The project was dedicated to Research and Development of a Correlator Stacker for a large number of channels mainly designed to operate in VIBROSEIS TM geophysical crews. | 4th Round Projects | 10.1007/978-94-009-7371-8_4 |
1982-01-01 | Extremely large superconducting magnets have been recognised as essential in projects such as energy storage or fusion. The increase in size and pulsative operation of such magnets makes applied forces in components complex and varied. It is important, therefore, to elucidate the behaviour of each magnet component against the various forces at cryogenic temperature. | Charpy Impact Test of Cloth Reinforced Epoxide Resin at Low Temperature | 10.1007/978-1-4613-3365-4_18 |
1982-01-01 | A conductor using flowing supercritical helium as a coolant has been adopted for the superconducting magnet being built by the Airco-Westinghouse industrial team for the Large Coil Program (LCP) at Oak Ridge National Laboratory. This conductor utilizes the “rope in a pipe” concept in which a large number of superconducting Nb_3Sn strands are formed into a cable and wrapped in a stainless steel jacket as shown in Fig. 1. | The Trials and Tribulations of Fabricating the Pipe for the “Rope in a Pipe” Nb_3Sn Superconductor | 10.1007/978-1-4613-3542-9_75 |
1981-09-01 | We report here the first results obtained by cooling a submillimeter quasioptical mixer, utilizing a Schottky diode in a corner reflector mixer structure. Measurements have been carried out at a wavelength of 434 microns. The diode inverse slope parameter V_o at low current decreases by a factor of 3 upon cooling to 50 K while the minimum system noise temperature of 5600 K (SSB), including the IF contribution, demonstrates a reduction of approximately 40% from the ambient temperature value. We also report improved system noise temperatures at 184 μm and 119 μm wavelengths of 38000 K and 64000 K (SSB), respectively. | Cryogenic operation of submillimeter quasioptical mixers | 10.1007/BF01006938 |
1981-06-01 | Use of reliability increase models to estimate the reliability of cryogenic systems | 10.1007/BF01148020 | |
1981-05-01 | Investigation of the performance of a bubble cryogenic gasifier | 10.1007/BF01159272 | |
1981-05-01 | Improved tips for gynecological cryogenic probes for the treatment of pretumorous disease in the cervix of the uterus | 10.1007/BF00572218 | |
1981-04-01 | 1. The elasticity modulus of unidirectional GRPs VIII and X decreases by 15%, on the average, with decreasing temperature from room to 4.2 °K. In this temperature range the Young's modulus of unreinforced bonding agent ÉDT-10 increases by a factor of three. 2. The ultimate strength of GRPs I-XI in tension, compression, and bending increases with decreasing temperature in the range 300-77 °K. With temperature reduced to 4.2 °K the behavior of all test GRPs with different straining methods is unstable, i.e., both an increase and a decrease in ultimate strength are observed; however, for practically all of the GRPs σ_f at 4.2 °K is higher than at room temperature. 3. With increasing fiber disorientation angle in relation to the loading direction, the strength of GRPs decreases over the whole temperature range. The temperature dependence of ultimate strength for specimens in the glass cloth weft direction is less defined, and their strength over the whole temperature range is much lower than for specimens cut in the glass cloth warp direction. 4. Of all the materials considered, the most stable is GRP IX. 5. In view of the nature of GRP failure at cryogenic temperatures, and in fact the breakup of material in the failure area into individual threads, it is possible to assume that specimen failure is facilitated by fracture of the matrix in the composite. 6. In the temperature range 300-4.2 °K the strength of GRPs I and III under tension is less sensitive to the effect of stress concentrators (a round hole in the specimen gauge length). | Mechanical properties of some glass-reinforced plastics at low temperature | 10.1007/BF00762501 |
1981-01-01 | Cryogenic liquids are being used as the active media for an increasing number of nonlinear optical devices. Results have been reported on stimulated Raman oscillators and amplifiers[1–4], third-harmonic generators[5], four-wave difference frequency generators[6, 7] and infrared Kerr switches.[8] Photo-acoustic and photo-refractive measurements of weak absorptions in these liquids are also a subject of current interest [9, 10], In this paper, we report third-harmonic generation (THG) and ac Kerr effect measurements which allow us to obtain the electronic nonlinearity (hyperpolarizability), the vibrational two-photon resonance nonlinearity, and the molecular reorientation contributions to the third-order susceptibilities, x^(3) of the cryogenic liquids CO, O_2, N_2 and Ar. Measurements of the electrostrictive and absorptive coupling of a laser radiation field to the liquid hydrodynamic modes are presented. These measurements are of interest because of their implications for the efficiencies and limitations of the nonlinear optical devices. Further, the relative simplicity of these media allow many of these quantities to be calculated or extrapolated from low density gas-phase measurements for comparison with these results. This should lead to an increased understanding of liquid-state properties. | Nonlinear Optics of Cryogenic Liquids | 10.1007/978-3-540-38609-4_16 |
1980-12-01 | A glass column containing a porous polymer was used to concen-trate headspace volatiles from enzymatically mediated reactions and inserted directly into the injection port of a gas liquid chromatog-raphy (GLC) for elution and separation of adsorbed volatiles. The polymer column was placed in an entrainment system attached to a water aspirator at 30 psi to collect volatiles produced by the en-zymatic reaction. A useful chromatogram was obtained from 1 g of raw material by this method. Volatiles collected in this manner could be stored on the polymer matrix at ambient temperatures without deleterious effects for subsequent GLC analysis. Multiple columns of the same or different trapping material could also be used in the entrainment system. | A preconcentration and subsequent gas liquid chromatographic analysis method for trace volatiles | 10.1007/BF02678925 |
1980-10-01 | Dependences to compute the cooling time of a single-channel object are obtained theoretically and confirmed experimentally. | Time to cool a cryogenic object by a gaseous cryogenic agent | 10.1007/BF00822136 |
1980-09-01 | Cryogenic vacuum pump | 10.1007/BF01148200 | |
1980-09-01 | Published data are examined and results are given from a survey of experiments on phase slip and heat transfer to liquids. | Phase slip and heat transfer to the liquid in film boiling of a cryogenic liquid in piston flow | 10.1007/BF00825919 |
1980-07-01 | Development of cryogenic systems based on cryogenic helium machines | 10.1007/BF01155953 | |
1980-07-01 | Improvement in schemes of cryogenic helium systems for cryostating of superconducting devices | 10.1007/BF01155950 | |
1980-07-01 | Design of highly efficient heat exchangers for cryogenic helium installations | 10.1007/BF01155952 | |
1980-07-01 | Perforated-plate heat exchangers for cryogenic helium units | 10.1007/BF01155954 | |
1980-03-01 | Laminar-vacuum heat insulation of cryogenic equipment based on glass paper made of microthin fiber | 10.1007/BF01155681 | |
1980-03-01 | Storage features of cryogenic liquids | 10.1007/BF01155679 | |
1980-01-01 | The period since World War II has been a very troubled one, but one of great economic and industrial expansion throughout the world. One consequence has been an exponential growth in the use of metals and other mineral-derived raw materials, and that growth has raised the question of whether the mineral requirements of industry can be met in future years. | Materials Resource Considerations for Cryogenic Engineering | 10.1007/978-1-4613-9859-2_1 |
1980-01-01 | Some cryogenic systems, such as superconducting magnetic energy storage and superconducting generators, require load-bearing supports to transfer forces to a room temperature (warm) structure. It is necessary to minimize the refrigeration power required to overcome heat leaks through the supports in order to improve system efficiency. | Minimization of Refrigeration Power for Large Cryogenic Systems | 10.1007/978-1-4613-9856-1_41 |
1980-01-01 | “Cryogenics” is a derivative from the Greek word Kryos meaning icy cold. There is no single temperature, at this date, that defines the beginning of the cryogenic region. Often temperatures of −73°C and colder are referred to as cryogenic, although this paper recognizes −50°C and colder as fitting the definition. Whereas cryogenics is the branch of physics that relates to the production and effects of very low temperatures [^1], a cryogen is the refrigerant that makes it happen. A dozen or more cryogens are available; however, nitrogen (N_2) and carbon dioxide (CO_2) are more commonly used for recycling processes. | Cryogenic Processing | 10.1007/978-1-4613-9859-2_6 |
1980-01-01 | Magnetic fusion reactors, equilibrium coils, and ohmic heating coils require large pulses of energy which are repeated over relatively short periods of time. Accelerator magnets fabricated with normal conductors or superconductors have similar operating conditions, the same pulse time, and require almost the same amount of energy, namely, hundreds to thousands of MJ. These large pulsed energies can affect a power grid adversely. | Energy Transfer in a System of Superconductive Magnets | 10.1007/978-1-4613-9856-1_7 |
1980-01-01 | The Cryogenic Engineering Section of the Superconducting Power Transmission Line Project at the Los Alamos Scientific Laboratory has been evaluating the performance of force-flow heat transfer systems. This includes the measurement of temperature profiles[^1], thermal pulse transmittal rates [^2] and the thermal performance of cryogenic insulation and refrigeration systems [^3] All of these tasks require the measurement of the mass flow rate of gaseous helium near 10 K provided by a closed-loop helium refrigeration system. An orifice flow meter installed within the cold box of a CTI model 1400 helium refrigerator/liquefier, along with the gas density inferred from pressure and temperature measurements, is used to determine the helium mass flow rate. This paper describes the calibration and use of this mass flow meter. | Experience with an Orifice Flow Meter Installed in a Helium Refrigerator | 10.1007/978-1-4613-9856-1_60 |
1980-01-01 | The movement of energy via pipeline is one of the cheapest methods of energy transmission, and since the system is buried underground, it is also acceptable environmentally. | Transmission and Distribution of Hydrogen | 10.1007/978-1-349-02635-7_3 |
1980-01-01 | Linen-base phenolic laminate is inexpensive, has high compressive mechanical strength, and can be easily fabricated. It has been widely used for substructures in large bubble-chamber magnets [^1] and large magnetohydrodynamic (MHD) magnets [^2,3] | Low-Temperature Measurement of the Thermal and Mechanical Properties of Phenolic Laminate, the Pultruded Polyester Fiberglass, and A & B Epoxy Putty | 10.1007/978-1-4613-9859-2_30 |
1980-01-01 | The TPC experiment at PEP is one of several colliding beam experiments which use thin superconducting solenoid magnets. The CELLO experiment at PETRA in Hamburg, Germany and a detector for the ISR at CERN in Geneva, Switzerland use superconductors with an aluminum matrix[^1–3]. The TPC magnet and a magnet to be used at Cornell University use the concept of a shorted secondary circuit to protect a high-current-density copper-based superconductor[^4]. | Construction and Testing of the Two-Meter-Diameter TPC Thin Superconducting Solenoid | 10.1007/978-1-4613-9856-1_22 |
1980-01-01 | The joints between single-core conductors [^1–3] and the joints between monolithic, copper-stabilized, multifilamentary Nb-Ti conductors [^4–6] have been investigated. In the past at Massachusetts Institute of Technology (M.I.T.) coils have been terminated by individually soldering each strand to a copper lug. In this investigation, techniques for making monolithic terminations of Nb-Ti and Nb_3Sn multifilamentary, multistrand cables were examined. | Monolithic Terminations for Multistrand Nb-Ti and Nb_3Sn Cables | 10.1007/978-1-4613-9859-2_72 |
1980-01-01 | Thermal properties of superfluid helium have been studied for more than 30 years; now they are being utilized in numerous laboratories investigating specific applications of superconductivity. One of the properties of great importance is its high thermal conductivity, which makes the liquid heat capacity of a cooling bath almost fully available to absorb local heat pulses. This behavior is of great interest for the cryogenic stabilization of pulsed superconducting magnet systems[^1]. | Control of Pressurized Superfluid Helium-II: Application to Loss Analysis | 10.1007/978-1-4613-9856-1_64 |
1980-01-01 | Vapor—liquid equilibrium (VLE) values for mixtures containing hydrogen, nitrogen, carbon monoxide, and methane are of interest to the gasification industry, especially in the purification of coke oven gases. There are three possible combinations of these four components to form hydrogen-containing ternary mixtures, namely, hydrogen—nitrogen—methane, hydrogen—nitrogen—carbon monoxide, and hydrogen—carbon-monoxide—methane. Although VLE values for these ternary systems have been published [^1–3] or reported [^4,5] over wide ranges of temperature and pressure, additional experimental data are required to further the understanding of the phase behavior of these mixtures. A thorough investigation of the available data reveals that, from the viewpoint of locating the probable ternary critical points, the most important temperature and pressure region should lie between — 170 and — 195ºC, and between 100 and 150 atm. It is for this reason that VLE data for these ternary systems together with the three hydrogen-containing binary systems of hydrogen—nitrogen, hydrogen—carbon monoxide, and hydrogen—methane were determined at — 180°C in the pressure range between 100 and 150 atm for selected compositions. In addition, two ternary data points were measured at — 170°C. It was anticipated that the experimental results thus obtained would indicate the possible existence and locations of ternary critical points in these systems and would describe the influence of these critical points, in conjunction with binary critical points, on the phase behavior of these ternary systems. | Phase Behavior of Three Hydrogen-Containing Ternary Systems | 10.1007/978-1-4613-9856-1_75 |
1980-01-01 | In a large superconducting magnet, such as the superconducting magneto-hydrodynamic (MHD) dipole system for the National Coal-Fired Flow Facility (CFFF SCMS) at the University of Tennessee Space Institute (UTSI), the conductor joints must be strong, highly reliable, of low resistance, reproducible, and made with reasonable speed. These aspects of conductor joining are being studied. | Mechanical and Electrical Properties of Resistance Welds at Cryogenic Temperatures | 10.1007/978-1-4613-9859-2_73 |
1980-01-01 | This paper describes the development of exergy—enthalpy thermodynamic charts for helium and nitrogen. The thermodynamic properties for nitrogen were generated from the Bender equation of state, while an equation developed by McCarty was used for helium. Special computer programs were developed to plot thermodynamic diagrams, in particular exergy—enthalpy diagrams. | The Construction and Use of Exergy Diagrams | 10.1007/978-1-4613-9856-1_79 |
1980-01-01 | The current plan for the Fermilab superconducting synchrotron (energy doubler) calls for the installation of approximately 1000 superconducting magnets in the 6-km tunnel of the main ring accelerator. Its 3 x 10^8-J emergency energy dump system [^1] is based on “safety leads” between 4 and 300 K situated after every fifth magnet. With this system, when a quench is detected the power supply is turned off and a 0.5-Ω air-cooled “energy fountain” resistor is switched into the coil buss at each of six energy transfer stations. This causes the magnet current to decay with a time constant of 10 s. This decaying current has to be diverted from the developing quench, and this is done by shunting the current out from the group of five magnets containing the quench by means of the “safety leads.” Protection for these magnets is achieved by firing their internal heaters which spread the normal zone to a safe size. The magnetic energy of these five magnets is transferred to the helium and mechanically vented [^2]. | Safety Leads | 10.1007/978-1-4613-9856-1_34 |
1980-01-01 | The Argonne National Laboratory, under the sponsorship of the Fossil Energy Division of the U. S. Department of Energy, has designed and is constructing a 6-T, 0.8-m minimum warm bore superconducting dipole magnet system for magnetohydrodynamic (MHD) research. The system will be installed and operated at the University of Tennessee Space Institute (UTSI) Coal Fired Fuel Facility (CFFF). The system will consist of a coil assembly contained in a liquid helium cryostat, a helium refrigerator/liquefier system, and controls and instrumentation for cooldown and steady-state operation[^1–4] | Cryogenic Aspects of the UTSI-CFFF Superconducting Dipole Magnet for MHD Research | 10.1007/978-1-4613-9856-1_4 |
1980-01-01 | Previous investigations [^1,2] have considered cryogenic metal treatment to improve the resistance of the material to wear and extend the useful life of machine parts. Service tests on several machine elements indicated that significant increases in part life could be achieved by soaking the part in liquid nitrogen temperatures (77 K) for several hours. Table I gives a summary of these results, showing that cryogenic treatment improved the wear resistance. There is little information in the literature, however, from which the wear improvement can be predicted quantitatively. | Cryogenic Treatment of AISI-T8 and C1045 Steels | 10.1007/978-1-4613-9859-2_17 |
1980-01-01 | The results of a series of low-temperature magnetic and calorimetric studies relating to the magnetic character of austenitic stainless steels are summarized and discussed. Twelve members of both the AISI 300 series and the proprietary Nitronic series, as well as other alloys, have been investigated from time to time in collaboration with J. C. Ho [^1], M. P. Mathur [^1], R. D. Smith [^2], R. L. Cappelletti [^3], H. W. King [^4], H. M. Ledbetter [^5,6], and S. C. Hart [^7]. The AISI 300 series alloys generally exhibit a superparamagnetic susceptibility temperature and field dependence superimposed on a background susceptibility whose temperature dependence passes through a cusp at low temperatures. The Nitronic alloys show a cusp but no superparamagnetism. | The Magnetic Character of Austenitic Stainless Steels | 10.1007/978-1-4613-9859-2_3 |
1980-01-01 | The superconducting magnet CELLO was tested with currents up to 3200 A at Saclay and has been installed at DESY in Hamburg where it will be used for particle physics experiments requiring colliding beams of electrons and positrons. The testing of this unique, large, one-layer solenoid provides an excellent opportunity to evaluate the theory of quench propagation under adiabatic conditions, that is, in a coil in which the conductors are not in direct contact with helium. In an early test of this coil, quenches occurred as a result of a broken conductor. This report describes the quenches that occurred, gives the details of the damaged conductor, and includes an analysis of the quenches. Observed axial quench velocities are compared to the calculated values based on both measurements and calculations of the thermal conductivity of the fabricated coil. The coil and conductor dimensions and characteristics are given in Table I The coil and conductor are shown in Fig. 1, and a complete description can be found elsewhere[^1]. | Quenches in the Superconducting Magnet Cello | 10.1007/978-1-4613-9856-1_21 |
1980-01-01 | In cryogenic gas processing, one of the process constraints can be the precipitation of solid carbon dioxide in the processing streams. The collection of solid carbon dioxide at strategic points in the process can significantly disrupt or completely destroy the effective operation of a process plant by changing its hydraulic characteristics. Theoretically, for any temperature below the triple point of carbon dioxide (−56.6°C) there exists the possibility of freezing. The freezing point is a strong function of the mixture composition and temperature. Obviously, the prediction of carbon dioxide solubility in light hydrocarbon mixtures can strongly affect the process scheme, particularly when the gas treating facility represents a significant portion of the project cost. | Prediction of CO_2 Solubility in Light Hydrocarbon Mixtures at Low Temperatures | 10.1007/978-1-4613-9856-1_72 |
1980-01-01 | The U. S. Air Force is currently developing electrical generators for a variety of airborne applications requiring high-power and high-voltage capability [^1]. The airborne environment imposes severe constraints on volume and weight which make a superconducting generator an attractive approach owing to its small size and high power-to-volume ratio. Since superconducting generators are in direct competition with other energy production schemes for these applications, the design of the cryogenic support subsystem strongly influences system potential. A study*, therefore, has been underway to evaluate techniques and system designs for providing the cryogenic cooling to support an airborne superconducting generator system. This paper describes the system constraints, airborne applications, and the resulting cryogenic cooling requirements. The design methodology and trade-off considerations are discussed for the airborne support system, the ground support system, and the cryogenic transport system. Primary emphasis was placed on minimizing the weight of the airborne system and providing the most cost-effective approach for supplying the cryogenic cooling from the wellhead source to the aircraft. | Cryogenic Support System for Airborne Superconducting Generators | 10.1007/978-1-4613-9856-1_39 |
1980-01-01 | For the production of synthetic natural gas (SNG), oxygen and steam have been proposed to gasify coal in first- and second-generation coal gasification processes. Because of the high capital cost associated with oxygen and steam production, efforts have been made to reduce or eliminate the oxygen and steam requirements and to reduce or eliminate the shift and methanation steps normally required to upgrade the Btu content of the produced gas. | Purification and Cryogenic Separation of SNG Produced from Coal | 10.1007/978-1-4613-9856-1_86 |
1980-01-01 | The superconducting magnet system (SCMS) consists of a superconducting magnet, magnet cryostat, a helium refrigerator/liquefier facility, a helium gas-handling system, apparatus for cryogenic transfer and storage, a magnet power supply, an integrated instrumentation and control system including a computer for magnet operation, data acquisition, system status and diagnosis, and magnet protection. The complete system will be tested at Argonne and installed at the Coal-Fired Flow Facility (CFFF) at the University of Tennessee Space Institute (UTSI) in 1981. The cryogenic aspects and magnet safety are described and analyzed elsewhere [^1,2]. | Final Design of a Superconducting MHD Magnet for the Coal-Fired Flow Facility at the University of Tennessee Space Institute | 10.1007/978-1-4613-9856-1_3 |
1980-01-01 | Friction is the resistance to movement of contacting surfaces. Wear is the surface degradation and material loss that result from mechanical interaction. Friction and wear are closely associated, but there is no direct relationship. Thus, high friction implies high wear, but the conditions leading to minimum friction for a given sliding couple do not necessarily minimize wear. | A Review of Antifriction Materials and Design for Cryogenic Environments | 10.1007/978-1-4613-9859-2_5 |
1980-01-01 | A study was recently made [^1] on the representation of pure-component properties by the variants of the van der Waals [^2] and the Redlich—Kwong (RK) [^3] equations of state. These variants were obtained by modifying the repulsive term of these equations with an appropriate analytical expression of the hard-sphere compressiblity factor. The results obtained indicate that the following equation, 1 % MathType!MTEF!2!1!+- % feaagaart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn % hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr % 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9 % vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x % fr-xb9adbaqaaeaacaGaaiaabeqaamaabaabaaGcbaaeaaaaaaaaa8 % qacaWGqbGaeyypa0JaaGPaVpaalaaapaqaa8qacaWGsbGaamivaaWd % aeaapeGaeqyXduhaaiaaykW7daWcaaWdaeaapeGaaGOmaiabew8a1j % abgUcaRiaadkgaa8aabaWdbiaaikdacqaHfpqDcqGHsislcaWGIbaa % aiaaykW7cqGHsislcaaMc8+aaSaaa8aabaWdbiaadggaa8aabaWdbi % aadsfapaWaaWbaaSqabeaapeGaaGimaiaac6cacaaI1aaaaOGaeqyX % duNaaiikaiabew8a1jabgUcaRiaadkgacaGGPaaaaaaa!56F1! $$ P = \,\frac{{RT}} {\upsilon }\,\frac{{2\upsilon + b}} {{2\upsilon - b}}\, - \,\frac{a} {{T^{0.5} \upsilon (\upsilon + b)}} $$ still possesses the qualities of realism and simplicity. | Simple and Generalized Equation of State for Vapor-Liquid Equilibrium Calculations | 10.1007/978-1-4613-9856-1_77 |
1980-01-01 | Aluminum and its alloys do not undergo abrupt transitions to a brittle state at low temperatures, and their ultimate strengths, yield strengths, and elongations at low temperatures are generally about as high or higher than those at room temperature. Aluminum alloys also possess good weldability and corrosion resistance. For these reasons, they are widely used as structural materials in the manufacturing of gas distribution equipment and tanks for storage and transportation of cryogenic liquids. | Fracture of Al-Mg6-Mn Plates and Welds at Cryogenic Temperatures | 10.1007/978-1-4613-9859-2_22 |
1980-01-01 | Interlaminar shear (ILS) strength is the load-carrying capacity of a layered filamentary composite under shear forces parallel to the layers. The term “strength” is commonly applied to a material. Actually, it is the property of a structure made from that material. A strength test is a structural test. By convention, however, the term “strength” and the numerical value of the test results have been assigned to the material of the test specimen. | A Study of Interlaminar Shear Strength at Cryogenic Temperatures | 10.1007/978-1-4613-9859-2_27 |
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