Influence of laser power on mechanical properties of FGM of SS316L and IN625 fabricated by direct metal deposition

Direct Metal Deposition (DMD) is a metal Additive Manufacturing (AM) process. It is used for producing sustainability Functionally Graded Materials (FGM) and repairing of sophisticated parts. In this present research, a commercially available DMD machine deposited three partial FGM blocks of size 26 mm wide × 34 mm thick × 32 mm heights. The commonly influence parameters on Ultimate Tensile Strength (UTS) are scan velocity and laser power. The powders used for deposition were Stainless Steel 316L (SS316L), Inconel 625 (IN625), and their three different compositions. ASTM E8 tensile samples were cut from those blocks by wire cut-EDM. Micro-tensile tests were carried out on ASTM E8 samples using a SHIMADZU micro-tensile machine. The results revealed that partial FGM sample-2 had high sustainability UTS of 532 MPa as compared to remaining two samples. It is illustrated that for joining two dissimilar materials to obtain high UTS thick layered (i.e., thickness more than 1 mm) gradient path method should be selected at the medium laser power available on the DMD machine. However, the sample-3 has higher hardness at high laser power

Chalcone synthase in rice (Oryza sativa L.): Detection of the CHS protein in seedlings and molecular mapping of the chs locus

The chalcone synthase is a key enzyme that catalyses the first dedicated reaction of the flavonoid pathway in higher plants. The chs gene and its protein product in rice has been investigated. The presence of a chalcone synthase (CHS) protein in rice seedlings and its developmental stage-specific expression has been demonstrated by western analysis. The chalcone synthase of rice was found to be immunologically similar to that of maize. A rice cDNA clone, Os-chs cDNA, encoding chalcone synthase, isolated from a leaf cDNA library of an indica rice variety Purpleputtu has been mapped to the centromeric region of chromosome 11 of rice. It was mapped between RFLP markers RG2 and RG103. RG2 is the nearest RFLP marker located at a genetic distance of 3.3 cM. Some segments of chromosome 11 of rice including chs locus are conserved on chromosome 4 of maize. The markers, including chs locus on chromosome 11 of rice are located, though not in the same order, on chromosome 4 of maize. Genetic analysis of purple pigmentation in two rice lines, Abhaya and Shyamala, used in the present mapping studies, indicated the involvement of three genes, one of which has been identified as a dominant inhibitor of leaf pigmentation. The Os-chs cDNA shows extensive sequence homology, both for DNA and protein (deduced), to that of maize, barley and also to different monocots and dicots

Isolation and characterization of expressed sequence tags (ESTs) from subtracted cDNA libraries of Pennisetum glaucum seedlings

Pearl millet (Pennisetum glaucum), used as forage and grain crop is a stress tolerant species. Here we identify differentially regulated transcripts in response to abiotic (salinity, drought and cold) stresses from subtracted cDNA libraries by single-pass sequencing of cDNA clones. A total of 2,494 EST sequences were clustered and assembled into a collection of 1,850 unique sequences with 224 contigs and 1,626 singleton sequences. By sequence comparisons the putative functions of many ESTs could be assigned. Genes with stress related functions include those involved in cellular defense against abiotic stresses and transcripts for proteins involved in stress response signaling and transcription in addition to ESTs encoding unknown functions. These provide new candidate genes for investigation to elucidate their role in abiotic stress. The relative mRNA abundance of 38 selected genes, quantified using real time quantitative RT-PCR, demonstrated the existence of a complex gene regulatory network that differentially modulates gene expression in a kinetics-specific manner in response to different abiotic stresses. Notably, housekeeping and non-target genes were effectively reduced in these subtracted cDNA libraries constructed. These EST sequences are a rich source of stress-related genes and reveal a major part of the stress-response transcriptome that will provide the foundation for further studies into understanding Pennisetum's adaptability to harsh environmental conditions