82,975 research outputs found
Method of making a rocket nozzle
A method is described for forming the interior of a nozzle having uneven walls so that a throat of smooth converging and diverging sides is provided for passing flow. A metallic insert material is placed within the flow passageway adjacent to the area where the sharper throat constriction is to be formed, so that the material will flow through the inlet into the throat space when liquefied
Pressure and protein denaturation
Kinetic analyses have indicated that moderate hydrostatic pressures, up to some 700 atmospheres, oppose reversible and irreversible denaturations of certain enzyme systems, apparent at temperatures above the normal optimum of the enzyme reaction, as well as at lower temperatures in the presence of denaturants such as alcohol (1-4). Qualitative observations have shown that such pressures also retard the precipitation of highly purified human serum globulin and egg albumin at 65° (5) and slow the destruction of specific antitoxic activity at the same temperature (6). In this study we have obtained quantitative data with regard to the influence of various pressures, up to 10,000 pounds per sq. in., and of low concentrations of ethyl alcohol on the time course of precipitation of human serum globulin (1) at 65° and pH 6.0
System cost performance analysis (study 2.3). Volume 1: Executive summary
A study is described which was initiated to identify and quantify the interrelationships between and within the performance, safety, cost, and schedule parameters for unmanned, automated payload programs. The result of the investigation was a systems cost/performance model which was implemented as a digital computer program and could be used to perform initial program planning, cost/performance tradeoffs, and sensitivity analyses for mission model and advanced payload studies. Program objectives and results are described briefly
The manufacture of antibodies in vitro
A protein solution with the properties of a specific antiserum to the triphenylmethane dye methyl blue has been made by treating a solution of bovine gamma-globulin and the dye with alkali and then slowly neutralizing the alkali. Some success has been obtained also in the formation of antibodies from other serum proteins and by other denaturation-renaturation procedures.
By heating solutions of gamma-globulin and antigen to 57°C. for several days antisera homologous to the antigens have been prepared. This method has been used successfully with the azodye 1,3-dihydroxy-2,4,6-tri(p-azophenyl-arsonic acid) benzene and with pneumococcus polysaccharide Type III. The antipneumococcus sera were found to precipitate the polysaccharide of Type III but not those of Types I and VIII and to agglutinate pneumococci of Type III but not those of Types I and II
Comment on ``Spin-glass transition of the three-dimensional Heisenberg spin glass''
Campos et al. [Phys. Rev. Lett. 97 (2006) 217204] claim that in the 3d
Heisenberg Spin Glass, chiral and spin sector ordering temperatures are
identical. We point out that in their analysis of their numerical data key
assumptions are made which are unjustified.Comment: published versio
Australian Vessel Performance in the East Coast Tuna Longline Fishery
A sample of daily observations on the activities of Australian vessels longlining for yellowfin tuna, Thunnus albacares, during 1987-90 was analyzed, using a production junction approach, to determine the effects of vessel characteristics and operational practices and conditions. Significant differences were found between the tuna fisheries in the northern and southern regions of the inshore yellowfin tuna fishery in the east Australian Exclusive Economic Zone. The type of vessel used, and fishing practices such as soaktime, patrolling the longline, and choice of surface water temperature were found to have significant effects on yellowfin tuna catch rates
Fluid quality in a self-pressurized container discharge line
Quality of cryogenic fluids in vertical discharge line during draining of saturated liquid from self-pressurized containe
The retention of S35-labelled bovine serum albumin on normal and immunized rabbit liver tissue
The S35-label of S35-BSA was detected in the liver tissue of rabbits to the extent of 0.02 per cent (10 µg or sime 1014 molecules) of the injected material at 140 days after injection.
The rate of loss of antigen at the termination of the experiment was of such an order that significant amounts would be expected to persist for at least several years.
Data are reported which extend the retention data previously reported on S35-labelled hemocyanin. They indicate that amounts of the order of 0.05 per cent (25 µg.) of antigen material persist at 330 days after injection.
All of the radioactivity of material retained in the liver tissue 6 weeks after injection was immunologically related to the original S35-BSA antigen.
Preliminary studies are reported which indicate that the retained antigen is bound to ribonucleic acid.
A new method is described for the isolation of p-azophenylsulfonate bovine serum albumin from tissue extracts by means of a Dowex 2 adsorbent
Effects of the thermal sterilization procedure on polymeric products
Properties of samples are tested, after thermal exposure, and values are compared with unexposed samples. Thermal stability or compatibility ratings of formulated or compounded organic polymers using trade names are made and degree of change in measured properties is assessed. Products are rated compatible, marginal, or not compatible
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