Influence of process parameters on mechanical and microstructural property of dissimilar friction stir welded joints of armor aluminium alloys AA7039 and AA5083

Friction stir welding (FSW) is an innovative, green and energy-efficient solid-state welding process. Which has been resolved the problems of defects related to microstructure and mechanical properties of welding joints of soft materials. FSW is also capable to join dissimilar materials of different melting points together with adequate efficiency and effectiveness. Present research work is an attempt to join the two dissimilar armor grad aluminium alloys i.e. AA7039 and AA5083 by FSW. Both materials are utilized as armor materials in defence. The process parameters such as tool rotation speed (RS), welding speed (WS) and tool tilt angle (TA) were utilized for variation at different five levels for experimentation. The experiments were designed by center composite design (CCD) of response surface methodology (RSM). The fabricated joints were examined for the variation in mechanical properties such as ultimate tensile strength (UTS), yield tensile strength (YTS) and percentage elongation (EL). Effects of the inputs parameters on the variation of the responses were validated by analysis of variance (ANOVA). The obtained results of aforesaid properties were utilized for the optimization of input parameters in the desirability approach. The desirability approach revealed that 1440 RPM of tool rotation, 32.1 welding speed and 2.4 tilt angle as an optimized set of parameters, which can fabricate the joint with 263.02 MPa UTS, 211.90 MPa YTS and 14.7% EL. The results of ANOVA and optimization were also verified by a change in the microstructure of FSWed joints

RADIATION PATTERN AND POLARIZATION SHIFTING OF ANTENNA USING FPGA & CORDIC

ABSTRAC

Modeling and Stress Analysis of Rounded Rectangular Inclusion Enclosed by FGM Layer

The aim of the present work is to model and analyze stresses around rounded rectangular inclusion enclosed with functionally graded material (FGM) layer. The inclusion has been considered in an infinite plate which is subjected to far-field tensile stress. The extended finite element method (XFEM) has been used to model the inclusion with non-conformal mesh. The level set functions of circular and rectangular shapes have been used to trace the inclusion boundary with mesh. The FGM has been considered as continuous varying mixture of inclusion and plate materials with power law function along normal direction to the inclusion interface. Young's modulus has been assumed to vary within FGM layer, whereas Poisson's ratio is kept constant. The stress distribution and stress concentration factor (SCF) have been analyzed for different geometrical and FGM parameters. It has been observed that XFEM with level set method efficiently model the difficult shape inclusions such as rounded rectangle. Applying the FGM layer smoothens the stress distribution around rounded rectangular inclusion and significantly reduces SCF. The position of maximum stress shifted from the inclusion interface toward the FGM layer interface. The least SCF has been noted with power law index n = 0.5 and FGM layer thickness t = r

Non-syndromic multiple supernumerary premolars: Clinicoradiographic report of five cases

Hyperdontia or supernumerary teeth in both arches without any syndromic manifestation are extremely rare. Supernumerary teeth are commonly associated with Gardner’s syndrome, cleft lip and palate, cleidocranial dysplasia and trichorhinopha-langeal syndrome. Five cases of non-syndromic multiple premolars of maxillary and mandibular arches in Indian patients are presented here. This case series reports three cases with multiple (9 in maximum), bilaterally impacted and erupted supernumerary teeth and two cases with supernumerary premolars in non-syndromic cases from Indian patients. Supernumerary teeth can be present in any region of the oral cavity. Although the occurrence of maxillary para-premolars is rare, radio-logical investigations play a major and decisive role in determining the management of such cases

Analysis of HGPRT − CRM + human lymphoblast mutants

Three 6-thioguanine-resistant mutants of the human diploid lymphoblast line MGL-8 were studied. The inactivation by heat of both HGPRT activity and antigenicity of the HGPRT immunologically cross-reacting material of the A30 mutant cells were not protected by PRPP, indicating that the HGPRT in A30 cells has an altered PRPP binding site, leading to lack of stabilization and rapid degradation of the enzyme. Two dimensional separations of the immunoprecipitates from extracts of the parental and mutant cell lines showed that the A35 mutant CRM has a more acidic isoelectric pH, while the A30 CRM has a more basic isoelectric pH and that the A30 protein has a faster rate of degradation than the wild-type HGPRT. The A30 CRM also has a smaller molecular size than the wild-type enzyme .Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45555/1/11188_2005_Article_BF01542643.pd

Mass spectrometry screening reveals widespread diversity in trichome specialized metabolites of tomato chromosomal substitution lines

Glandular secreting trichomes of cultivated tomato (Solanum lycopersicum) and close relatives produce a variety of structurally diverse volatile and non-volatile specialized (‘secondary’) metabolites, including terpenes, flavonoids and acyl sugars. A genetic screen is described here to profile leaf trichome and surface metabolite extracts of nearly isogenic chromosomal substitution lines covering the tomato genome. These lines contain specific regions of the Solanum pennellii LA0716 genome in an otherwise ‘wild-type’ M82 tomato genetic background. Regions that have an impact on the total amount of extractable mono- and sesquiterpenes (IL2-2) or only sesquiterpenes (IL10-3) or specifically influence accumulation of the monoterpene α-thujene (IL1-3 and IL1-4) were identified using GC-MS. A rapid LC-TOF-MS method was developed and used to identify changes in non-volatile metabolites through non-targeted analysis. Metabolite profiles generated using this approach led to the discovery of introgression lines producing different acyl chain substitutions on acyl sugar metabolites (IL1-3/1-4 and IL8-1/8-1-1), as well as two regions that influence the quantity of acyl sugars (IL5-3 and IL11-3). Chromosomal region 1-1/1-1-3 was found to influence the types of glycoalkaloids that are detected in leaf surface extracts. These results show that direct chemical screening is a powerful way to characterize genetic diversity in trichome specialized metabolism

Identification of a single nucleotide change in a mutant gene for hypoxanthine-guanine phosphoribosyltransferase (HPRT Ann Arbor)

HPRT Ann Arbor is a variant of hypoxanthine (guanine) phosphoribosyl-transferase (HPRT: EC 2.4.2.8), which was identified in two brothers with hyperuricemia and nephrolithiasis. In previous studies, this mutant enzyme was characterized by an increased K m for both substrates, a normal V max , a decreased intracellular concentration of enzyme protein, a normal subunit molecular weight and an acidic isoelectric point under native isoelectric focusing conditions. We have cloned a full-length cDNA for HPRT Ann Arbor and determined its complete nucleotide sequence. A single nucleotide change (T→G) at nucleotide position 396 has been identified. This transversion predicts an amino acid substitution from isoleucine (ATT) to methionine (ATG) in codon 132, which is located within the putative 5′-phosphoribosyl-1-pyrophosphate (PRPP)-binding site of HPRT.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47622/1/439_2004_Article_BF00291707.pd

Law Enforcement Access to Library Records

The Task Force on Law Enforcement Access to Library Records was charged with establishing guidelines for responding to requests from law enforcement authorities for library records involving patron data, keeping in mind the American Library Association Code of Ethics which recognizes that we protect each library user?s right to privacy and confidentiality. In addition, the Task Force recommended policies on retention of all types of patron records that are needed for the operation of the library

Influence of Process Parameters on Mechanical and Microstructural Property of Dissimilar Friction Stir Welded Joints of Armor Aluminium Alloys AA7039 and AA5083

686-695Friction stir welding (FSW) is an innovative, green and energy-efficient solid-state welding process. Which has been resolved the problems of defects related to microstructure and mechanical properties of welding joints of soft materials. FSW is also capable to join dissimilar materials of different melting points together with adequate efficiency and effectiveness. Present research work is an attempt to join the two dissimilar armor grad aluminium alloys i.e. AA7039 and AA5083 by FSW. Both materials are utilized as armor materials in defence. The process parameters such as tool rotation speed (RS), welding speed (WS) and tool tilt angle (TA) were utilized for variation at different five levels for experimentation. The experiments were designed by center composite design (CCD) of response surface methodology (RSM). The fabricated joints were examined for the variation in mechanical properties such as ultimate tensile strength (UTS), yield tensile strength (YTS) and percentage elongation (EL). Effects of the inputs parameters on the variation of the responses were validated by analysis of variance (ANOVA). The obtained results of aforesaid properties were utilized for the optimization of input parameters in the desirability approach. The desirability approach revealed that 1440 RPM of tool rotation, 32.1 welding speed and 2.4 tilt angle as an optimized set of parameters, which can fabricate the joint with 263.02 MPa UTS, 211.90 MPa YTS and 14.7% EL. The results of ANOVA and optimization were also verified by a change in the microstructure of FSWed joints