Phytic acid (PA, myo-inositol 1,2,3,4,5,6-hexakisphosphate), or its salt form, phytate, is commonly regarded as the major anti-nutritional component in cereal and legume grains. Breeding of low phytic acid (lpa) crops has recently been considered as a potential way to increase nutritional quality of crop products. In this study, eight independent lpa rice mutant lines from both indica and japonica subspecies were developed through physical and chemical mutagenesis. Among them, five are non-lethal while the other three are homozygous lethal. None of the lethal lines could produce homozygous lpa plants through seed germination and growth under field conditions, but two of them could be rescued through in vitro culture of mature embryos. The non-lethal lpa mutants had lower PA content ranging from 34 to 64% that of their corresponding parent and four of them had an unchanged total P level. All the lpa mutations were inherited in a single recessive gene model and at least four lpa mutations were identified mutually non-allelic, while the other two remain to be verified. One mutation was mapped on chromosome 2 between microsatellite locus RM3542 and RM482, falling in the same region as the previously mapped lpa1-1 locus did; another lpa mutation was mapped on chromosome 3, tightly linked to RM3199 with a genetic distance of 1.198 cM. The latter mutation was very likely to have happened to the LOC_Os03g52760, a homolog of the maize myo-inositol kinase (EC 2.7.1.64) gene. The present work greatly expands the number of loci that could influence the biosynthesis of PA in rice, making rice an excellent model system for research in this area.

The influence of hydrogen on the mechanical and fracture properties of some martensitic advanced high strength steels studied using the linearly increasing stress test, Corrosion Science http://dx. HighlightsHydrogen influence increased with strength, charging potential, and decreasing applied stress rate.The hydrogen influence was manifest by reduced strength, changed fracture and decreased ductility.The decrease in yield stress was attributed to solid solution softening by hydrogen Hydrogen caused a change at the fracture stress when the specimen was mechanically unstable The fracture changed from ductile cup-and-cone fracture to macroscopically brittle shear fracture. ABSTRACTThe influence of hydrogen on the mechanical and fracture properties of four martensitic advanced high strength steels was studied using the linearly increasing stress test and electrochemical hydrogen charging. The hydrogen influence increased with steel strength, decreasing charging potential, and decreasing applied stress rate. Increased hydrogen influence was manifest in (i) the decreased yield stress attributed to solid solution softening by hydrogen and (ii) the reduced macroscopic ductility, and by the change from ductile cupand-cone fracture to macroscopically brittle shear fracture, attributed to a dynamic interaction of hydrogen with the dislocation substructure somewhat similar to the HELP mechanism.Keywords: A. steel; B. SEM; C. hydrogen embrittlement 10].The martensitic AHSS (MS-AHSS) are the strongest, but exhibiting the lowest ductility [11]. Strength and hardness increase with increasing carbon content, whereas the ductility and toughness decrease with increasing carbon content. The lack of ductility also limits formability of these steels, which is important, because auto bodies are mechanically shaped from sheet steel. Nevertheless, MS-AHSS are important because they have the highest strength-to-price ratio among AHSS [8]. MS-AHSS find applications in the parts of the vehicle which require good crash resistance, such as bumper beams and reinforcements, door intrusion beams and reinforcements, windscreen upright reinforcements, and B-pillar reinforcements [1,[12][13][14].Hydrogen embrittlement (HE) has long been the bane of high-strength steels [15][16][17].HE is a failure mode caused by the presence of a relatively small amount of hydrogen. HE may trigger catastrophic failures at relatively-small applied loads, or may cause degradation of ductility and toughness. Recent studies have revealed some HE susceptibility for some AHSS [18][19][20][21][22]. However, past attempts to predict HE resistance based on the microstructure, composition and processing, have not been successful. Hence, a much deeper understanding of how hydrogen interacts with steel is essential to reduce or eliminate HE in AHSS.Several mechanisms have been proposed for HE. For non-hydride forming metals such as steel, the following three mechanisms are the most likely: (i) hydrogen-enhanced decohesion (HEDE), (ii) hydrogen-enhanced local plasticity (HELP)...

Please cite this article in press as: J. Venezuela, et al., Influence of hydrogen on the mechanical and fracture properties of some martensitic advanced high strength steels in simulated service conditions, Corros. Sci. (2016), http://dx. a b s t r a c tThis work investigated the influence of hydrogen on the mechanical and fracture properties of four martensitic advanced high-strength steels in simulated service conditions: (i) immersed in 3.5 wt% NaCl solution, and (ii) at substantial applied stress rates. There was little influence of hydrogen for the four MS-AHSS in 3.5 wt% NaCl. Similarly, there was little influence of hydrogen for hydrogen-precharged MS1300 and MS1500 subjected to tensile tests at substantial stress rates. The diffusivities of hydrogen in MS980, MS1300 and MS1500 were similar. The use of a Pt counter electrode during cathodic hydrogen charging is not recommended.

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