bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fondaparinux and the Management of Heparin-Induced Thrombocytopenia: The Journey Continues
Authors: Blackmer Allison Beck , Oertel Maryann D , Valgus John M 
Published: September 2009

Objective: To review the available literature addressing the role of fondaparinux in the management of heparin-induced thrombocytopenia (HIT). Data Sources: Primary articles were identified by a MEDLINE search (2004–June 2009) of English-language literature using the MeSH headings fondaparinux, heparin, low-molecular-weight heparin, and thrombocytopenia. Relevant consensus guidelines (2006–June 2009) were also identified. Study Selection and Data Extraction: All published studies and case reports, as well as relevant consensus guidelines, evaluating the use of fondaparinux for the management of HIT were included. Data Synthesis: The role of fondaparinux in the management of HIT is a therapeutic controversy challenging clinicians today. An open-label, prospective pilot study of 7 patients with acute HIT supports fondaparinux as an alternative anticoagulant. Additionally, a total of 12 patients with HIT from a larger case study and retrospective cohort were successfully treated with fondaparinux. Much of the supporting data exists in the form of case reports, each demonstrating normalization of platelet counts without any evidence of new thrombosis. The differences in clinical scenarios as well as the role and dose of fondaparinux make interpretation of these reports difficult. Three case reports have been published raising concerns regarding fondaparinux causing or failing to manage HIT appropriately. However, common weaknesses such as small sample sizes and nonuniform definitions of HIT limit the usefulness of these findings. The updated American College of Chest Physicians consensus guidelines now recognize fondaparinux as an option in the management of HIT; however, the level of evidence supporting this is of low quality. The use of fondaparinux as a bridging agent between direct thrombin inhibitor and warfarin therapy has been proposed. A recently published case report gives support to this approach. Conclusions: Controlled clinical trials evaluating the use of fondaparinux in the management of HIT need to be completed before this therapy can be routinely recommended.
Techniques in Thermal Analysis: Hyphenated Techniques, Thermal Analysis of the Surface, and Fast Rate Analysis
Authors: Pan Wei-Ping , Judovits Lawrence 
Published: September 2009

Description
Nine peer-reviewed papers reflect the latest research in thermal analysis, including fast scan calorimetry in both instrument development and techniques.
Sections cover:
Hyphenated Techniques—seven papers cover the use of thermogravimetric analysis (TGA) with another technique. Topics deal with temperature-modulated differential scanning calorimetry; improved modeling when using hyphenated techniques; a simple calibration method for the quantitative use of mass spectrometry with TGA for a variety of encountered off gases; and much more.
Fast Rate Analysis—covers fast scan calorimetry in both instrument development and techniques. Fast heating rates were employed to study epoxy curing and fast rate analysis allowed the separation of the glass transition and cure exotherm.
Thermal Analysis of the Surface—discusses the use of a modified atomic force microscope (AFM), or Micro-Thermal Analysis, that uses the AFM probe as a thermal device.
Fatigue and Fracture of Medical Metallic Materials and Devices
Authors: Mitchell M. R. , Jerina Kenneth L. 
Published: September 2009

Description
Get the latest information on the thermal and mechanical properties of shape memory alloys (SMA's) and metallic medical materials and devices.
Eleven peer-reviewed papers:
• Define the environments in body-specific locations such as the superficial femoral artery, carotid, abdominal and thoracic arteries
• Develop constitutive expressions for the deformation response of nitinol via specific test methodologies and data analyses
• Develop the appropriate mechanics analyses for cumulative damage calculations and to ultimately
• Ascertain the fatigue lifetime of medical devices in the human body.
The principle focus of this new publication is on nitinol since these unique alloys offer the designer new dimensions in controlling the shape of devices used in medical and many structural applications. Shape memory devices such as valves, actuators, clutches, and gaskets are proposed for monitoring units, drive systems, and repair schemes.
STP 1481 also covers other metallic medical materials and devices.
Radiation Effects in Reactor Structural Materials
Authors: Reynolds Myron B. 
Published: September 2009

The effect of fast neutron radiation on the impact strength of two precipitation hardening stainless steels has been determined using full-size Charpy V-notch specimens. The brittle-ductile impact transition temperature of type 17-4 PH stainless steel aged at 1100 F was found to increase from approximately room temperature to values above 300 F after irradiation at 545 F to exposures in excess of 5 x 1019 neutrons per sq cm &gt; 1 Mev. The impact strength of doubly aged austenitic type A-286 stainless steel was found to increase from about 30 ft-lb in the unirradiated condition to approximately 50 ft-lb after irradiation.
A technique for performing in-reactor slow-cycle fixed range fatigue tests on thin-walled tubing is described. Results of preliminary work on type 304 stainless steel tubing are presented. Irradiation in a core position in the General Electric Test Reactor during tests was found to produce a threefold decrease in strain cycle life of type 304 stainless steel in a configuration similar to that of fuel element cladding.
Neutron Irradiation Effects in A-286, Hastelloy X, and René 41 Alloys
Authors: Robertshaw F. C. , Moteff J. , Kingsbury F. D. , Pugacz M. A. 
Published: September 2009

Studies to determine the effect of neutron environment on the stress-rupture properties of A-286, Hastelloy X, and René 41 alloys are described. Specimens were irradiated in the Engineering Test Reactor at approximately 540 and 650 C to fast neutron dosages of 4 to 11 × 1019 nvt (En ≧ 1 Mev). Postirradiation stress-rupture tests were conducted at 540 and 650 C. The effect of reheat treatment following irradiation was investigated.
The results indicate that the stress-rupture strengths of A-286 and Hastelloy X alloys at 540 and 650 C were significantly reduced by irradiation. A similar effect was observed in René 41 at 650 C. Complete reheat treatment following irradiation did not restore the radiation-induced loss in strength in A-286 alloy at 540 or 650 C, or in René 41 at 650 C. Reheat treatment appeared to effect recovery in the rupture strength of Hastelloy X at 540 C, but not at 650 C.
The A-286 alloy showed substantial reductions in rupture ductility, particularly at 650 C. A similar loss in ductility in one of two heats of René 41 was observed at 650 C. The ductility of Hastelloy X, though affected, remained at relatively high levels.
Structural studies have been initiated on control and irradiated specimens of A-286 alloy. Initial results are discussed.
Effects of Austrolling on the Properties of Crucible 422 Stainless Steel
Authors: Westgren R. C. , Dulis E. J. 
Published: September 2009

Austrolling Crucible 422 stainless steel increased yield strength by as much as 45 per cent and tensile strength by 30 per cent. The fracture toughness characteristics, as indicated by net fracture strength and Kc values, were significantly superior after austrolling. The net fracture strength of conventionally heat-treated steel was 122,000 psi and of austrolled steel was as high as 212,000 psi.
The increased resistance to cracking under stress in a salt solution and in a cathodically hydrogen-charged environment (hydrogen cracking) was significantly improved after austrolling.
A relationship was shown between mechanical fatigue notch crack propagation and stress corrosion and hydrogen cracking. The microstructural changes imparted by austrolling influenced fracture characteristics that were reflected in mechanical and electrochemical properties of the steel.
High-Strength Stainless Steel by Deformation at Low Temperatures
Authors: Floreen S. , Mihalisin J. R. 
Published: September 2009

A series of nickel-chromium stainless alloys made by air and vacuum melting were rolled 20 or 40 per cent at temperatures ranging from —320 to 400 F. Smooth and sharp-notched sheet-tensile properties were measured after heat treating the cold-rolled pieces for 24 hr at 800 F. Yield strengths up to 260 ksi were obtained. Hardening resulted primarily from martensite formation, and also from work hardening of the austenite prior to transformation. The yield strengths were correlated in terms of composition.
Lowering the silicon content to 0.1 per cent significantly raised the toughness. Over the ranges studied none of the remaining elements had effects comparable to silicon. The toughness at a given strength level also depended upon the rolling conditions, but not upon the per cent martensite.
Tests at −320 F with a low-silicon alloy showed a notch-tensile ratio of 1.0 at 297 ksi ultimate tensile strength. The results suggest that a low-silicon 301-type composition would have good cryogenic properties.
Evaluation and Application of Stainless Steels in Cryogenic Environments
Authors: Hurlich A. , Scheck W. G. 
Published: September 2009

Cold-rolled stainless steel sheet possesses combinations of properties and characteristics which make it suitable for use as cyrogenic propellant tankage for large missiles and spacecraft. While extra cold-rolled Type 301 is used in both the Atlas and Centaur vehicles, other alloys including Types 304 L and 310 have also been evaluated for these applications by screening tests including tension, notched-tension, crack propagation, cross-tension, and shear tests on resistance spot welded joints, and static tension and cyclic fatigue tests of large complex weld joint specimens. Data are presented on the properties of the three alloys in base metal and weld joint configurations.
Type 301 stainless steel can be cold rolled to the highest tensile strength of the three alloys because of its lowest austenite stability, resulting in considerable transformation to martensite upon cold rolling. This factor is also responsible for embrittlement which is particularly manifested in reduced strength and fatigue resistance of welded joints tested at liquid hydrogen temperature. Use of more highly alloyed and more stable stainless steel such as Type 310 eliminates low-temperature embrittlement but at sacrifice in payload potential because of reduced strength.
Low-temperature embrittlement of cold-rolled Type 301 was overcome by incorporating sheet of nickel foil between two sheets of stainless steel to be resistance welded. The nickel alloys into the weld nugget and produces completely stable austenitic nuggets which are tough and ductile at −423 F. Both the strength and fatigue resistance of missile weld joints are markedly increased by the nickel foil, permitting reliable use of Type 301 in cryogenic tankage down to −423 F. Nickel also greatly increases the ability of radiography to detect weld defects in nickel enriched spot welds and has resulted in improvement in welding procedures and quality control.
Modified Type 316 Stainless Steel with Low Tendency to form Sigma
Authors: Spaeader C. E. , Brickner K. G. 
Published: September 2009

A study was made to determine whether decreasing the chromium or the chromium and molybdenum contents of AISI Type 316 stainless steels would decrease the tendency for sigma-phase formation without impairing the elevated-temperature strength of the steel.
The results of this study showed that in comparison with AISI Type 316, a modified Type 316 steel with about 14 per cent chromium instead of the normal 16 to 18 per cent chromium had about the same coefficient of thermal expansion, similar room- and elevated-temperature tensile properties, similar creep and creep-rupture strengths, and slightly better hot workability. Moreover, the impact strength of modified Type 316 steel after exposure for 6000 hr at 1100, 1300, and 1500 F was markedly superior to that of AISI Type 316 steel. The results of X-ray and metallographic studies indicated that the superior impact strength of the modified Type 316 was the result of lesser amounts of sigma formed in the new steel.
Effect of Composition and Section Size on Mechanical Properties of Some Precipitation Hardening Stainless Steels
Authors: Clarke W. C. , Garvin H. W. 
Published: September 2009

Applications have developed in which the high-strength properties associated with precipitation hardening stainless steel alloys are of considerable interest in large and medium section sizes. In a number of instances, transverse loading is involved. In common with other high strength materials, ductility in the transverse direction is lower than in the longitudinal direction. This paper presents transverse tension data obtained on a number of these alloys which serve to define this characteristic in a variety of shapes and sizes. The alloys discussed are 17-7 PH, PH 15-7 Mo, PH 13-8 Mo, 17-4 PH, and 15-5 PH. It is demonstrated that structural characteristics, particularly delta ferrite and certain precipitates, markedly influence transverse ductility and, in large section of 17-7 PH and PH 15-7 Mo, longitudinal ductility. Vacuum remelting does not help the directional ductility characteristics in compositions in which delta ferrite is a major controlling factor. Alloys in which composition changes have been incorporated to vary these structural factors have been developed. One of these is PH 13-8 Mo which is a composition employing aluminum as a hardening agent in which the analysis is adjusted to eliminate delta ferrite. This steel has excellent transverse ductility, especially in products made from double vacuum melted ingots. Another new material which has been called 15-5 PH contains copper as a hardening agent and is free of delta ferrite. In this modified composition the transverse ductility across the dead center of large sections is somewhat inferior to the transverse ductility obtainable at intermediate and surface locations in products made from air-melted ingots. Consumable electrode vacuum remelting eliminates the lower dead center transverse ductility in delta ferrite free products, such as 15-5 PH, by minimizing gross segregation, and excellent transverse ductility is obtained in any location.
Some discussion is presented on the effects of varying heat treatments on transverse ductility of several of these steels.
Further Studies on the Formation of Sigma in 12 to 16 per cent Chromium Steels
Authors: Ludwigson D. C. , Link H. S. 
Published: September 2009

Sigma, a hard intermetallic phase in the iron-chromium system, has a complex tetragonal structure and was formerly thought to be the cause of 885 F embrittlement. Although previous investigators have found that sigma can form in ferritic stainless steels at chromium contents as low as 13 per cent and at temperatures as high as about 1500 F, the alpha — alpha plus sigma boundary of this system was not known with certainty at low chromium concentrations where equilibrium is established very slowly. The present study concerns the effects of exposures at 900, 1050, and 1200 F for durations up to 76,000 hr on annealed specimens and on cold-reduced specimens from a series of laboratory heats of simulated commercial purity steels containing nominally 12, 13, 14, 15, and 16 per cent chromium.
In the cold-reduced condition, all the steels developed sigma during exposure at 900 F, all but the 12 per cent chromium steel developed sigma at 1050 F, and none of the steels developed sigma at 1200 F. In the annealed specimens, sigma had formed within the time studied only in the 14, 15, and 16 per cent chromium steel specimens exposed at 1050 F.
As would be expected, the cold reduced specimens softened during exposure. However, precipitation hardening (885 F embrittlement) occurred in the annealed specimens containing 15 and 16 per cent chromium during exposure at 900 F. The 16 per cent chromium steel, and to a lesser extent the 15 per cent chromium steel, overaged after prolonged exposure at this temperature.
These results show that the alpha — alpha plus sigma boundary for commercial purity chromium steels is located at a lower chromium concentration than was heretofore reported. In addition, the observation—for what is believed to be the first time—of the reversal of 885 F embrittlement by overaging substantiates the prediction made by other investigators.
Relationship Between Metallurgical Structure and Properties of a Precipitation Hardening Stainless Steel
Authors: Aggen G. N. , Kaltenhauser R. H. 
Published: September 2009

The mechanical properties and corrosion resistance of AM-355, a precipitation-hardening stainless steel, were found to be highly dependent upon carbide morphology. Corrosive attack in salt spray could always be associated with carbide precipitation at matrix discontinuities such as austenite or delta-ferrite grain boundaries. Continuous carbide precipitation at austenite grain boundaries was found to promote stress-corrosion failures in salt spray and to adversely affect certain mechanical properties such as ductility and impact strength.
Heat treatments, based upon the transformation characteristics of the alloy, were developed which produced uniform carbide dispersions. This structure resulted in significant improvements in mechanical properties and resistance to rusting, pitting, and stress corrosion in salt spray.
Carbide morphology was studied by light and electron microscopy as affected by: (1) heat treatment variables such as solutioning temperatures and times, cooling rates, and precipitation temperatures and times; (2) prior history of the alloy; and (3) transformation characteristics of the alloy.
Users of the alloy have accepted the new heat treatment that was developed. This has led to new applications for the alloy in relatively severe marine environments.
A Method for Testing and Evaluating the Joint Properties of a Copper Liner Soldered in an Aluminum Casting
Authors: Davis Moss V. 
Published: September 2009

A testing method is described for measuring the strength of the solder bond between a copper liner and an aluminum casting used for making bi-metallic electrical conductor connections. The rupture of the solder bond as the result of a burnishing operation revealed the need for an adequate method to test the strength of the soldered joint.
The test described in this paper provides an empirical quantitative measurement of the joint strength of the solder bond. The stress required to peel the liner from the cable groove in the casting was measured by means of a straight spring balance.
The test results obtained from daily production samples were subjected to statistical quality control analysis. Charts of the results thus obtained are shown and discussed. Factors influencing the strength of the solder bond and its corrosion characteristics are discussed.
Radioactivation Analysis—Specific for Trace Element Determinations
Authors: Leddicotte G. W. 
Published: September 2009

Nuclear technology developments concerned with the interpretation of nuclear particle production processes and the measurement of the resulting end products of the interactions of these particles with matter have made it possible to create very sensitive and specific analytical methods based on radioactivation analysis. Nuclear particle, particularly neutron, outputs from both accelerators and reactors that can be used in this analysis method are sufficiently intense to make it possible to determine very small amounts of most elements in many different types of sample materials. In effect, in a radioactivation analysis, the radioactivity of the radioisotope induced into a stable isotope of the element during a nuclear particle irradiation becomes a “fingerprint” of that stable isotope, and a measurement of its intensity makes it possible to determine quantitatively the concentration of the stable isotope in a sample.
A number of investigators routinely use radioactivation analysis in trace impurity problems. In many of these applications, limits of measurement much more sensitive than those possible by more conventional analytical methods have been obtained. Also, it has been observed that the half-life and the radiations emitted by a particular radionuclide being used as the “fingerprint” are never exactly duplicated by any other radionuclide; thus, radioactivation analysis is a very specific method. It is also extremely free of the contamination difficulties experienced in other analytical methods unless the contamination has been introduced into the sample before the start of the nuclear particle irradiation.
The most used method is that of neutron radioactivation. At Oak Ridge National Laboratory, neutron radioactivation analysis has been used to determine microgram and submicrogram amounts of almost all of the elements in many different sample materials. It is the intent of this report to describe certain neutron radioactivation analysis applications used in the determination of trace elements in metals. Information about multisample handling techniques, irradiation methods, processing of irradiated sample materials, and radioactivity measurements by means of gamma spectrometry employed in these applications are given. Typical data obtained in the analysis of high-purity metals such as silicon, titanium, bismuth, zirconium, aluminum, and columbium are reported. The paper concludes with some speculations about the use of commercially available irradiation equipment in routine activation analysis problems in the metals industry.
The Minimization of Variables in Equipment and Techniques for Performing Skid Trailer Tests
Authors: Goodwin W A , Whitehurst E A 
Published: September 2009

A development program to improve equipment and field-testing techniques where skid trailers are involved has included revisions of the Tennessee trailer and changes in testing procedures.
This paper discusses (1) a reliable technique for measuring the pavementtire forces during skidding of a trailer test wheel, (2) equipment for controlling the quantity of water at the pavement-tire interface and for recording test vehicle speed, and (3) a procedure for evaluating tires so that test tires of different composition may be interchanged. Tire pressure is shown not to be important, whereas tire hardness materially influences measured coefficient. A procedure for recording longitudinal position of the test trailer is well suited for the torque type force-measuring system and is useful for long-term studies involving periodic measurements of friction on the same roadway surface.
Phenoxy Resin—A New Thermoplastic Adhesive
Authors: Bugel T. E. , Norwalk S. , Snedeker R. H. 
Published: September 2009

This paper discusses a new high-molecular-weight thermoplastic polymer recently developed in the laboratories of the Union Carbide Plastics Co. Its repeating unit is the same as commercial solid epoxy coating resins, but differs in that it is much higher in molecular weight (30,000 versus 340 to 4000) and does not contain terminal epoxy functionality. It is thermally stable and can be fabricated by most techniques applicable to thermoplastics. The material is strong, tough, rigid, and exhibits good dimensional stability. It is completely amorphous with a major glass transistion temperature range in the area of 100 C.
Its relationship to epoxy resins is reflected in its adhesive nature. High bond strengths are obtained with numerous substrates—for example, 3300 psi tensile lap shear strength to aluminum. Such bonds are maintained to a large extent under a wide variety of environmental conditions with a maximum temperature range of 200 F.
Historically, one of the serious limitations of thermoplastic adhesives has been poor creep resistance. The performance of the subject material, however, surpasses that of commonly used thermosetting adhesives.