Available low temperature thermocouple information and services

Voltage vs temperature data for thermocouple pairs at low temperatures - cryogenic temperatur

Cryogenic thermocouple calibration tables

Thermocouple calibration standards are developed for low-temperature thermocouple materials. Thermovoltage, thermopower, and the thermopower derivative are presented in tabular and graphical form

SAM 2 measurements of the polar stratospheric aerosol. Volume 9: October 1982 - April 1983

The Stratospheric Aerosol Measurement (SAM) II sensor aboard Nimbus 7 is providing 1.0 micron extinction measurements of Antarctic and Arctic stratospheric aerosols with a vertical resolution of 1 km. Representative examples and weekly averages including corresponding temperature profiles provided by NOAA for the time and place of each SAM II measurement are presented. Contours of aerosol extinction as a function of altitude and longitude or time are plotted, and aerosol optical depths are calculated for each week. Typical values of aerosol extinction and stratospheric optical depth in the Arctic are unusually large due to the presence of material from the El Chichon volcano eruption in the Spring of 1982. For example, the optical depth peaked at 0.068, more than 50 times background values. Typical values of aerosol extinction and stratospheric optical depth in the Antarctic varied considerably during this period due to the transport and arrival of the material from the El Chichon eruption. For example, the stratospheric optical depth varied from 0.002 in October 1982, to 0.021 in January 1983. Polar stratospheric clouds were observed during the Arctic winter, as expected. A representative sample is provided of the ninth 6-month period of data to be used in atmospheric and climatic studies

Cryogenic thermocouple tables

Cryogenic standardized thermocouple materials table

High precision cryogenic thermal conductivity standards

New apparatus allows accurate simultaneous measurement of thermal conductivity, electrical resistivity, and thermopower for technically important materials, such as new or uncommon alloys. A list of materials investigated is presented. Sources for obtaining data on these materials, as well as the source giving a description of the apparatus, are cited

Thermocouple installation

A thermocouple assembly which includes a plug having a pair of small diameter holes near one end thereof which are spaced a small distance apart to leave a thin quantity of plug material between the holes is presented. There are a pair of thermocouple wires extending through the different holes and with the outer ends of the wires joined to the thin quantity of plug material which lies between the holes to form a thermocouple junction

Finishing store lambs from organic hill and upland farms OF0119

1. The aim of this study was to assess the economics and constraints associated with home finishing lambs on a range of organic hill and upland farms in England and Wales, and to evaluate the potential for further finishing on registered farms in the lowlands. 2. The current state of the organic sheep sector is briefly reviewed. This identifies problems of scale, limited premia and uneveness of supply as limiting factors to more rapid development of the market and associated production systems. 3. To quanitfy the effect of organic management on financial performance, hill and upland farms were classified under four typical systems, depending on the degree of intensification. 4. Without a sizeable area of improved ground, to which fertiliser and other inputs could have been applied conventionally, flocks based on high hill or marginal hill systems were least affected by switching to organic management. Flock Gross Margin on the marginal hill declined by approximately 7%. 5. On more intensive farms, typified by Welsh hill or upland farming systems, there is greater potential to finish lambs at higher stocking rates under conventional management, and the consequences of changing to organic management are greatly increased. Assuming a 10% premium for fnished organic lambs, deviating from convetional practice to produce store lambs or finish lambs at higher production cost, reduced flock Gross Margin by approximately 12-15%. Without a premium, this deficit increased to 15-20%. 6. The Organic Aid Scheme can make good the likely income loss during the first two years after conversion, when the highest rates are payable. However, in the long-term organic flocks must compete solely on the basis os a premium paid for finished, and ideally, for store lambs. 7. Physical and financial constraints were identified as t wy systems had not developed linking potential production of store lambs in the hills/uplands with finishing on organic farms in the lowlands. These were mainly scale and infrastructure, availability of suitable feeds and the likely level of return to the lowland farmer from a store lamb finishing enterprise. Potential sources of feed for finishing organic lambs were assessed. These include permanent pasture, short-term leys, catch crops, grazed set-aside land and conserved fodder. 8. Integration with existing organic systems of all types was estimated to have the potential to finish an extra 10-15,000 lambs per annum, equivalent to the number of lambs currently receiving an organic premium. 9. Further opportunities to expand finishing capacity on lowland farms were examined. Mixed organic farms are likely to have little or no capacity to finish bought in store lambs, except where overall stocking rates are constrained by insufficient ewe/suckler cow quota, or where catch crops are added to the rotation. 10. The addition of a store lamb enterprise to lowland systems was calculated to increase farm Gross MArgin by 2-3%, depending on the type of farm (dairy, stockless arable, or mixed). This represented a marginal return on capital invested in a store lamb finishing enterprise of 9-24%. 1. The financial risks involved, the availability of suitable labour and fixed equipment, and reluctance to vary arable rotations, make store lamb finishing enterprises less attractive to the lowland farmer. 12. Beyond the capacity to increase the number of certified lambs currently offered by up to 50%, greater opportunities are only likely to develop, when there is a significant increase in land (particularly on arable farms) entering conversion

Effects of modifications to the space shuttle entry guidance and control systems

A nonlinear six degree of freedom entry simulation study was conducted to identify space shuttle guidance and control system software modifications which reduce the control system sensitivity to the guidance system sampling frequency. Several modifications which eliminated the control system sensitivity and associated control limit cycling were examined. The result of the modifications was a reduction in required reaction control system fuel

Determination of ASPS performance for large payloads in the shuttle orbiter disturbance environment

A high fidelity simulation of the annular suspension and pointing system (ASPS), its payload, and the shuttle orbiter was used to define the worst case orientations of the ASPS and its payload for the various vehicle disturbances, and to determine the performance capability of the ASPS under these conditions. The most demanding and largest proposed payload, the Solar Optical Telescope was selected for study. It was found that, in all cases, the ASPS more than satisfied the payload's requirements. It is concluded that, to satisfy facility class payload requirements, the ASPS or a shuttle orbiter free-drift mode (control system off) should be utilized

Development of the reentry flight dynamics simulator for evaluation of space shuttle orbiter entry systems

A nonlinear, six degree of freedom, digital computer simulation of a vehicle which has constant mass properties and whose attitudes are controlled by both aerodynamic surfaces and reaction control system thrusters was developed. A rotating, oblate Earth model was used to describe the gravitational forces which affect long duration Earth entry trajectories. The program is executed in a nonreal time mode or connected to a simulation cockpit to conduct piloted and autopilot studies. The program guidance and control software used by the space shuttle orbiter for its descent from approximately 121.9 km to touchdown on the runway