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HAYNES® 282® alloy was developed by Haynes International as an age-hardenable, yet fabricable, wrought Ni-base superalloy. To date, the alloy has been specified for a number of applications, most notably in the hot sections of both aero- and industrial gas turbines. A Time-Temperature-Transformation (TTT) diagram is a useful guide to assess an alloy’s behavior during thermo-mechanical processing and heat treating. Starting with the (commercially relevant) 1149 °C (2100 °F) mill-annealed condition, a time (0.1–100 h)—temperature (649–1121 °C (1200–2050 °F)) exposure matrix was executed. Precipitates, which had formed as a result of these exposures, were analyzed by light microscopy, scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS), and, in selected cases, by x-ray diffraction (XRD). Chiefly, γ′ and two types of carbides, Cr-rich M23C6 and Mo-rich M6C, were found. Approximate C-curves for these phases were constructed, and some implications for the alloy’s processing and properties characteristics are discussed.

Unusual gold-colored onions were selected from a F3 family originating from a cross between US-type yellow and Brazilian yellow onions. HPLC analysis showed that the gold onions contained a significantly reduced amount of quercetin, the most abundant flavonoid in onions. This result indicated that an early step in the flavonoid biosynthesis pathway might be abnormal in these onions. The expression of flavonoid synthesis genes isolated from onions was examined in gold onions and compared to that in onions of other colors by RT-PCR. The results showed that all genes were transcribed in gold onions as in red onions. In order to identify any critical mutations in flavonoid synthesis genes encoding enzymes involved in early steps of the pathway, the genomic sequence of chalcone isomerase (CHI) was obtained. A premature stop codon and a subsequent single base-pair addition causing a frameshift were identified in the coding region of the CHI gene in the gold onions. Co-segregation of the mutant allele of the CHI gene and the gold phenotype was investigated in the original F2 segregating population. Genotyping of three color groups (red, yellow and gold) of F2 onions revealed perfect co-segregation of the mutant CHI allele with the gold phenotype. All tested gold F2 onions were homozygous for the mutant CHI allele. This perfect co-segregation implies that the presence of a premature stop codon in the gold CHI gene results in an inactive CHI. Inactivation of CHI results in a block in the flavonoid biosynthesis pathway and the accumulation of chalcone derivatives, including a yellow pigment which might be responsible for the gold color in onions.

Laves phases with AB{sub 2} compositions are a common type of topologically close-packed structures, with three polytypes typically observed: cubic C15 (MgCu{sub 2}), hexagonal C14 (MgZn{sub 2}), and dihexagonal C36 (MgNi{sub 2}). There are over 360 binary Laves phases reported so far. Such an abundance of Laves phases has been attributed to the geometric principles for the ordered arrangement of atoms on lattice sites. Considering the great amount of research devoted to Laves phases, thermodynamic information of Laves phases is very limited and no review or compilation of such information is available, even though such information is imperative for understanding the bonding characteristics, phase stability, point defect mechanism, and mechanical properties of Laves phases. The fact that Laves phases can only be stabilized within an R{sub A}/R{sub B} range of 1.05 to 1.67 is obviously related to the geometric packing condition in the Laves phases. However, a systematic analysis of thermodynamic information, especially enthalpies of formation of Laves phases, may offer a new approach to understand this size-ratio effect in controlling Laves phase formation.

The effects of nickel additions to iron aluminides are investigated with respect to vacancy concentrations and solid-solution hardening. Lattice parameters, densities, vacancy concentrations, and hardnesses were measured for FeAl alloys (40, 45, 48, 50, and 51 at. pct Al) with up to 12 at. pct Ni additions, as quenched at both 700 °C and 1000 °C. It is found that Ni does not prevent the elimination of thermal vacancies, as has been suggested in previous studies. However, the equilibrium vacancy concentrations are affected by the Ni additions. No clear evidence of solid-solution hardening by the Ni additions themselves was found. Instead, it appears that the role of Ni in hardening FeAl is through the effect the Ni has on the vacancy concentration. It was found that the hardness of most of the Ni-containing FeAl alloys could be directly correlated to the square root of the vacancy concentration.

HAYNES® 242® alloy, based primarily on the Ni-25Mo-8Cr system, derives its low thermal expansion characteristics from its composition and its high strength concomitant with high ductility from a long-range ordering reaction upon an aging heat treatment. This combination has enabled the alloy continually to find a challenging range of applications in the aerospace industry at up to 1300°F (704°C). These include seal rings, containment rings, duct segments, casings, rocket nozzles, etc. In conjunction with the creep strength and environmental resistance, the low cycle fatigue (LCF) behavior is an important material property affecting the service life of 242 alloy components. The low cycle fatigue behavior of 242 alloy was studied under fully reversed strain-controlled mode at 800°F (427°C), 1000°F (538°C), 1200°F (649°C) and 1400°F (760°C) using a triangular wave form with a frequency of 0.33 Hz. Results are presented in terms of cycles to crack initiation and failure. The magnitudes of fatigue lives at total strain range ≤ 0.7% at 800, 1000 and 1200°F are significantly greater than those of solid solution strengthened alloys. Additionally, stress-controlled LCF tests were performed at 1200°F (649°C) on 242 alloy as well as 909 alloy (for comparison). The paper will discuss the results of these two test programs.Copyright © 2011 by ASME

A recently developed wrought γ'-strengthened superalloy, HAYNES® 282® alloy, is introduced. The new alloy is a candidate for several high-temperature applications in both aero and land-based gas turbine engines. It is also being considered for aerospace structural components, as well as automotive and steam turbine applications. The metallurgical features of the new alloy are reported, and the relationship between these features and certain key properties of the alloy is discussed. It was found that carefully balancing the equilibrium amount of the γ' phase was crucial for producing an alloy which could be readily formed and welded, and yet still maintain exceptional creep strength. Too high levels of the γ' phase can lead to difficulties in fabrication, particularly the phenomenon of strain-age cracking. However, a certain amount of γ' is necessary for adequate creep, tensile, and fatigue strength. The γ' level in 282 alloy was optimized to achieve the best balance of strength and fabricability. Alloy properties such as creep, tensile, low-cycle fatigue, and thermal stability were presented for 282 alloy along with those of comparative alloys, R-41 alloy, Waspaloy alloy, and 263 alloy. The fact that 282 alloy was found to have equivalent or better mechanical properties compared to alloys with higher γ' content can be attributed in large part to the alloy's outstanding thermal stability.

Key properties for wrought gamma-prime strengthened alloys used in aero and land-based gas turbine engines include fabricability, creep strength, and resistance to thermal fatigue. Since a definitive test method for measuring thermal fatigue resistance has not yet been accepted in the industry, isothermal low cycle fatigue (LCF) data are often used as a substitute. In this study, the LCF behavior of several gamma-prime strengthened sheet alloys was investigated. The test program emphasized the LCF behavior of HAYNES® 282® alloy, a material designed for excellent creep strength and fabricability (especially weldability). Data was also taken on other gamma-prime strengthened alloys including 263 alloy, R-41 alloy, and Waspaloy alloy for which little to no data existed in literature for sheet material. Fully reversed, strain-controlled LCF testing was performed at temperatures ranging from 1200 to 1600°F (649 to 871°C) on 0.125” (3.2 mm) thick sheet. The results of the testing are presented along with some microstructural characterization. HAYNES and 282 are registered trademarks of Haynes International.Copyright © 2007 by ASME

A new wrought, gamma-prime strengthened superalloy, HAYNES 282 alloy, has been developed for high temperature structural applications, especially those in aero and land-based gas turbine engines. The new alloy possesses a unique combination of creep strength, thermal stability, and fabricability not found in currently available commercial alloys. The new alloy has excellent creep strength in the temperature range of 1200 to 1650°F (650 to 900°C), surpassing that of Waspaloy alloy and approaching that of R-41 alloy. This level of creep strength is realized despite the alloy having a significantly lower volume fraction of the strengthening gamma-prime phase. The lower gamma-prime content of the new alloy provides a considerable improvement in terms of fabricability and resistance to strain-age cracking, a problem often associated with this class of alloys. In this paper, the major characteristics and attributes of the new alloy including mechanical properties, oxidation resistance, thermal stability, and weldability are presented.Copyright © 2006 by ASME

Ever increasing demands for lower gas turbine operating costs have led to the need for longer lasting components. This in turn, requires the availability of alloys which are reliable to such long lifetimes. In the mill produced condition, most alloys have desirable microstructures and mechanical properties. However, after exposure to the harsh temperatures found in gas turbine engines, the microstructures of most alloys will begin to change. The effects on the mechanical properties of such microstructural changes can range from mild deterioration to significant degradation. In this paper, the effects of thermal exposures at temperatures from 1200 to 1600°F for durations up to one year on the mechanical properties of three wrought gas turbine alloys will be reported. The alloys will include HAYNES® 188 alloy (Co-Ni-Cr-W), HAYNES 230® alloy (Ni-Cr-W), and HAYNES HR-120® alloy (Fe-Ni-Cr-Nb-N).Copyright © 2005 by ASME

A new locus conditioning a pink trait in onions was identified. Unusual pink onions were found in haploid populations induced from an F(1) hybrid between yellow and dark red parents and in F(3) populations originating from the same cross. Segregation ratios of red to pink in F(2), backcross, and F(3) populations indicated that this pink trait is determined by a single recessive locus. RT-PCR was carried out to look for any differential expression of anthocyanin synthesis genes between dark red and pink F(3) lines. The transcript level of anthocyanidin synthase (ANS) was significantly reduced in the pink line. To determine whether this reduced transcription is caused by other regulatory factors or by mutations in the ANS gene itself, ANS gene sequences from both dark red and pink F(3) lines were compared to detect any polymorphisms. Polymorphisms were identified, and subsequently utilized as molecular markers for the selection of ANS alleles. Absolute co-segregation of the pink allele and the ANS allele from the pink line was observed in parents, F(1) and F(3) populations. These results indicate that reduced transcription of the ANS gene caused by mutations in a cis -acting element is likely to result in the pink trait in onions.

Effects of a potassium permangenate gas absorbent and storage at 2 o C on quality changes in modified atmosphere packaged diced onions was studied. A 3 mil packaging film resulted in equilibrated O 2 of 2.65% and CO 2 level of 3.65%. Gas absorbent resulted in reduced ethylene, carbon dioxide and sulfur volatiles. Maximum shear force values and total phenolics increased during storage, but were not affected by gas absorbent. Glucose and fructose concentrations declined within one day after processing, which coincided with an increase in sucrose. Sugar concentrations remained stable thereafter, and were not affected by gas absorbent. Microbe colony forming units (CFU) increased during storage to 5.8 in controls and 7.1 (log CFU/g) in absorbent treated samples after 10 days at 2 o C

This paper provides a review of recent progress on point defect and solute hardening in binary and ternary B2 intermetallics. As is the case for disordered metallic solutions, the presence of point defects and solute atoms in ordered intermetallic compounds results in solid solution hardening (SSH). However, factors unique to ordered systems are often responsible for unusual hardening effects. Binary compounds with identical crystal structures can exhibit significantly different hardness behavior. Ternary solute additions to ordered compounds can give rise to apparent solid solution softening as well as unexpectedly rapid hardening. These effects arise from the interaction of multiple defect types as well as the presence of multiple sublattice sites available for solute occupation. Therefore, before the SSH behavior of ordered intermetallics can be properly studied, it is necessary to develop an understanding of the types and quantities of the point defects which are present. Three recent studies by the authors are reviewed. Much of the work was done on NiAl and FeAl in binary form as well as with ternary additions. Defect concentrations over wide ranges in alloy composition and quenching temperature were determined using the ALCHEMI (atom location by channeling enhanced microanalysis) technique combined with vacancy measurements. Hardness values were also measured. It was found that most of the observed SSH effects could be rationalized on the basis of the measured point defect concentrations.

In a prior report (Pike, L.M., Khym, J.X., Jones, M.H., Lee, W.H., and Volkin, E. (1980) J. Biol. Chem. 255, 3340-3347), it was observed that CTP synthesis and concomitant incorporation of CMP into RNA and dCMP into DNA were markedly reduced in cells cultured in the presence of cycloheximide and puromycin. Experiments described here with Novikoff hepatoma cells reveal that the purine biosynthetic pathway is similarly affected. When the cells are subjected to cycloheximide (30 or 60 microgram/ml) or puromycin (100 microgram/ml), there is a substantial reduction in the bioconversion of hypoxanthine, adenosine, and deoxyadenosine into guanylate compared to untreated cultures. Whereas synthesis (counts per min/nmol) of pool ATP was 70 to 100% of controls, that of pool GTP was 20 to 35% of controls. Incorporation of AMP into RNA was 40 to 60% of controls, but that of GMP was only 10 to 25% of controls. Incorporation of dAMP into DNA averaged 10% of controls, but that of dGMP was only 4% of controls. Synthesis of guanylates from formate by the de novo pathway was similarly reduced, but incorporation of guanosine, which enters via kinase action alone, was not disproportionately lowered. These results suggest that protein synthesis inhibitors cause a severely reduced availability of newly synthesized GTP and CTP as well as their deoxy counterparts, dGTP and dCTP, the proximal precursors for the synthesis of RNA and DNA. However, the nanomolar levels of all nucleoside triphosphates remain high, probably as a result of recycling of nucleic acid breakdown products. Thus, reduced synthesis of these compounds may restrict nucleic acid synthesis only if some sort of compartmentation leads to a limitation of these precursors at the site(s) of nucleic acid synthesis.

Germination and radicle elongation experiments were performed with six cultivars of cucumber (Cucumis sativus L.) at seven salinity concentrations (0, 0.8, 4.0, 6.0, 9.0, 12, and 15 dS·m−1). Increasing salinity has no effect on final germination percentage after 5 days, but did decrease radicle elongation. In seedling growth studies with salinity levels ranging from 0.8 to 12 dS·m−1, increasing salt levels decreased shoot length and shoot dry weight. Analysis of shoot tissue from these seedlings indicated that higher salinity levels increased concentrations of Ca and Na, while Mg and K concentrations decreased. Yield and fruit quality were measured in a greenhouse study at two salinity levels (1.6 and 4.0 dS· m−1). Salinity significantly decreased fruit yield in five of six cultivars, but had no effect on fruit quality. Seedling shoot length of a cultivar grown at 9.0 dS· m−1 was correlated with relative yield at 4.0 dS· m−1. A salinity screening technique based on this relationship is proposed.

When protein synthesis is effectively inhibited in Novikoff cell cultures by various drugs, there is a marked suppression of labeling of cytidiane nucleotides (mainly CTP) from exogenously supplied (/sup 3/H)uridine. The inhibition could be caused by a reduced activity of CTP synthetase, the enzyme catalyzing the conversion of UTP to CTP, since (/sup 3/H)UTP is readily produced. The variety of the drugs used appears to argue against a direct effect of the drugs on CTP synthetase, since three different glutarimide antibiotics (cycloheximide, streptimidone, and emetine) and puromycin, which has a quite different chemical structure, are equally effective. An increase of the cytidine nucleotide pool size is observed in most instances of drug treatment; however, feedback inhibition of CTP synthetase is considered unlikely because of a lack of correlation between the degree of inhibition of (/sup 3/H)CTP production and the extent of accumulation of the cytidine nucleotides. There is a marked inhibition of RNA synthesis when all protein synthesis inhibitors are present; but almost complete inhibition of RNA synthesis by actinomycin D produces only a slight inhibition in (/sup 3/H)CTP production, indicating that the block in the conversion of UTP to CTP results from inhibited protein synthesis rather than from inhibitedmore » RNA synthesis. Examination of the labeling pattern of both RNA and DNA nucleotides following drug treatment gave further evidence for inhibited CTP production. Inhibition of protein synthesis elicited a much greater reduction of the suppression ratio (experimental/control ratio) for RNA-CMP labeling than for RNA-UMP labeling and an even greater reduction of the suppression ratio for DNA-dCMP labeling compared to DNA-dTMP labeling. The effect was also obtained in HeLa cell cultures, but is not restricted to neoplastic cell lines since it was seen with normal human diploid fibroblast cultures.« less

The inheritance of parthenocarpy in cucumber is conditioned by an incomplete dominant gene P. In the homozygous condition PP produces parthenocarpic fruits early, with the first developing generally by the fifth node. Heterozygous Pp plants produce parthenocarpic fruits later than homozygous plants and fewer in number. The homozygous recessive pp produces no parthenocarpic fruits. Trapping of pistillate flowers was effective in identifying homozygous PP plants but failed in accurately identifying heterozygous plants. Screened cages or field isolation of gynoecious lines are efficient means of accurately identifying all parthenocarpic plants.

Gibberellin A4/A7 was compared with GA3 for staminate flower induction on an inbred gynoecious cucumber line grown under field conditions in Michigan. Gibberellin A4/A7 spray applications at 50 ppm were found to induce significantly greater numbers of staminate flowers than GA3 applied at 1000 ppm without causing excessive stem elongation or brittleness often associated with high dosage of GA3.

Microscopic observations revealed that the epidermal layer of fruit of MSU 35G (warty) was composed of cells whose longest axis were perpendicular to the fruit surface and about 50 µ thick. The epidermal layer of fruit of MSU 6902 (non-warty) was composed of cells approximately 20 µ thick with little elongation in either visible axis. The F1 (warty) and warty fruit in the F2 exhibited a cellular shape similar to the warty parent. However, the thickness of epidermal cells of these warty progency were significantly less than that of the warty parent when observed in cross-section. Epidermal cell thickness of warty fruit observed in cross-section became increasingly less as the percentage of MSU 6902 in the genetic background increased. Subepidermal cells of fruit with non-warty skin were larger than corresponding cells of warty fruit. The epidermal cell shape of MSU 6902 was linked with the non-warty characteristic. Epidermal cell thickness is inherited independently of epidermal cell shape.

1. As shown by a double-radioisotope technique in vivo, at a non-lethal dose of cycloheximide, a stimulation of nuclear RNA synthesis occurred by 12 h after the treatment; the stimulation lasted over 48 h. Analysis of radioactive nuclear RNA by gel electrophoresis demonstrated that most of the cycloheximide-stimulated synthesis could be accounted for by known rRNA precursors (45 S, 41 S, 32 S and 28 S). 2. During the inhibitory phase of protein synthesis, 2 h after cycloheximide treatment, synthesis of the poly(A)-containing mRNA isolated from the cytoplasmic ribonucleoprotein complexes with an oligo(dT)-cellulose column was stimulated, whereas the synthesis of rRNA was slightly inhibited. However, during the stimulatory phase of protein synthesis, 24 h after cycloheximide treatment, the syntheses of both poly(A)-containing mRNA and rRNA were enhanced. 3. Kinetic studies revealed that the newly synthesized RNA species were transported from the nuclei, integrated into the ribonucleoprotein complexes, and associated with both free and membrane-bound polyribosomes. 4. These data corroborate our proposal that the stimulated protein synthesis after cycloheximide administration involves gene transcription.

In a prior report (Pike, L.M., Khym, J.X., Jones, M.H., Lee, W.H., and Volkin, E. (1980) J. Biol. Chem. 255, 3340-3347), it was observed that CTP synthesis and concomitant incorporation of CMP into RNA and dCMP into DNA were markedly reduced in cells cultured in the presence of cycloheximide and puromycin. Experiments described here with Novikoff hepatoma cells reveal that the purine biosynthetic pathway is similarly affected. When the cells are subjected to cycloheximide (30 or 60 microgram/ml) or puromycin (100 microgram/ml), there is a substantial reduction in the bioconversion of hypoxanthine, adenosine, and deoxyadenosine into guanylate compared to untreated cultures. Whereas synthesis (counts per min/nmol) of pool ATP was 70 to 100% of controls, that of pool GTP was 20 to 35% of controls. Incorporation of AMP into RNA was 40 to 60% of controls, but that of GMP was only 10 to 25% of controls. Incorporation of dAMP into DNA averaged 10% of controls, but that of dGMP was only 4% of controls. Synthesis of guanylates from formate by the de novo pathway was similarly reduced, but incorporation of guanosine, which enters via kinase action alone, was not disproportionately lowered. These results suggest that protein synthesis inhibitors cause a severely reduced availability of newly synthesized GTP and CTP as well as their deoxy counterparts, dGTP and dCTP, the proximal precursors for the synthesis of RNA and DNA. However, the nanomolar levels of all nucleoside triphosphates remain high, probably as a result of recycling of nucleic acid breakdown products. Thus, reduced synthesis of these compounds may restrict nucleic acid synthesis only if some sort of compartmentation leads to a limitation of these precursors at the site(s) of nucleic acid synthesis.

The development of a high yielding, pink root resistant, medium length storage shortday onion (Allium cepa L.) with improved shipping quality and maturing slightly later than ‘Texas Early Grano 502’ (TEG502) was the objective in the development of this cultivar. ‘Texas Grano 1025Y’ (TG1025Y) extends the South Texas onion season by 7 to 10 days beyond the ‘TEG502’ maturity season.

The development of a late maturing, high yielding, disease resistant shortday onion (Allium cepa L.) with improved shipping quality and medium length storage characteristics was the objective leading to selection and increase of this cultivar.

The development of a late maturing, high yielding, pink root resistant shortday onion (Allium cepa L.) with improved shipping quality was the objective for introduction of this cultivar.

The development of a high yielding, pink root-resistant [Pyrenochaeta terrestris (Hansen) Gorenz, Walker, and Larson], mild, sweet, shortday onion (Allium cepa L.) with improved shipping quality was the objective for the onion breeding program in the Texas Agricultural Experiment Station. ‘Texas Grano 1015Y’ (TG1015Y) is a very mild and sweet cultivar with those quality characteristics.

A true hermaphrodite cucumber was derived from the andromonoecious cultivar ‘Crystal Apple’. Hybrids developed by using gynoecious lines and the hermaphrodite line, TAMU 950, were 100% gynoecious. Fruits produced on the hybrids were similar in size and shape to that of the gynoecious parent. Use of the hermaphrodite in the production of such totally gynoecious hybrids permits the blending of precise quantities of a monoecious pollinator with hybrid seed before planting. Production of 100% gynoecious hybrids in this manner make parthenocarpic hybrids feasible.

Two gynoecious inbred lines of cucumber, ‘Gy 3’ and ‘MSU 35G’ their hybrids with the hermaphroditic ‘TAMU 950’ and backcrosses of the hybrids to their respective gynoecious parents were treated with gibberellin to test the phenotypic stability of gynoecism. Hybridization with ‘TAMU 950’ stabilized the gynoecious character and gibberellin A4/A7 provided a good test of stability.

‘TAMU Triple Cross’ is a three-way hybrid pickling cucumber (Cucumis sativus L.) developed for mechanical harvesting. It is the first American pickling-type hybrid cucumber developed from three inbreds. ‘TAMU Triple Cross’ exhibits several outstanding characteristics including high yield, desirable fruit shape, dark green color, excellent processing qualities both as brinestock and fresh pack, broad spectrum resistance to cucumber diseases, and finally, an improved and less expensive system for production of hybrid seed (1,2,3).