Friction Stir Welding of Similar Metals by Taguchi Optimization Technique -A Review

In order to meet the global competition and the survival of products in the market a new way of thinking is necessary to change and improve the existing technology and to develop products at economical price.This paper discusses use taguchi experiment design technique for maximizing tensile strength of friction stir welding AA6061 and AA6061. In friction stir welding, the joints are formed in the solid state by utilizing the heat generated by friction. The objectives of this study are obtaining friction weld element of aluminium 6061 to aluminium 6061 and optimising the friction stir welding parameters in order to establish the weld quality. Effect of tensile strength of friction stir welding process parameter (Rotational speed, travel speed, axial force and tilt angle) is evaluated and optimum welding condition for maximum tensile strength is determined

Microstructural Modifications of As-Age Hardening 7071 Aluminium Alloy using Friction Stir Welding

Objective: Friction stir welding (FSW) is a relatively new solid state welding technique for similar and dissimilar materials, especially on current interest with Aluminium 7071 to Aluminim 7071. Method/Analysis: The present paper discusses the process parameters followed by mechanical properties and microstructures which affect the weld strength. Findings: Mechanical properties-Tensile strength attained with different process parameters and Microstructures are obtained by Optical Metallurgical Microscopy (MET SCOPE-1) and a Scanning Electron Microscopy equipped with an X-radiation detector EDS Conclusion/Application: In this study Similar FSW between Al 7071 to Al 7071plates with thickness 6mm were performed. The future research will contain creep tests and microstructural investigations using aluminium 7071 alloy using TEM microscopy (Transmission Electron Microscopy).It is demonstrated that FSW of aluminium to aluminium alloys is becoming an emerging technology with numerous commercial applications

A Low Lyman Continuum Escape Fraction of <10%<10\% for Extreme [OIII] Emitters in an Overdensity at z∼3.5\sim3.5

Recent work has suggested extreme [OIII] emitting star-forming galaxies are important to reionization. Relatedly, [OIII]/[OII] has been put forward as an indirect estimator of the Lyman Continuum (LyC) escape fraction ($f_{esc}$) at $z\gtrsim4.5$ when the opaque IGM renders LyC photons unobservable. Using deep archival U-band (VLT/VIMOS) imaging of a recently confirmed overdensity at $z\sim3.5$ we calculate tight constraints on $f_{esc}$ for a sample (N=73) dominated by extreme [OIII] emitters. We find no Lyman Continuum signal ($f_{esc}^{rel} < 6.3^{+0.7}_{-0.7} \%$ at $1\sigma$) in a deep U-band stack of our sample (31.98 mag at 1$\sigma$). This constraint is in agreement with recent studies of star-forming galaxies spanning $z\sim1-4$ that have found very low average $f_{esc}$. Despite the galaxies in our study having an estimated average rest-frame EW([OIII]$\lambda5007$)$\sim400\AA$ and [OIII]/[OII]$\sim 4$ from composite SED-fitting, we find no LyC detection, which brings into question the potential of [OIII]/[OII] as an effective probe of the LyC--a majority of LyC emitters have [OIII]/[OII]$>3$, but we establish here that [OIII]/[OII]$>3$ does not guarantee significant LyC leakage for a population. Since even extreme star-forming galaxies are unable to produce the $f_{esc}\sim10-15\%$ required by most theoretical calculations for star-forming galaxies to drive reionization, there must either be a rapid evolution of $f_{esc}$ between $z\sim3.5$ and the Epoch of Reionization, or hitherto observationally unstudied sources (e.g. ultra-faint low-mass galaxies with $\log(M/M_\odot)\sim7-8.5$) must make an outsized contribution to reionization.Comment: 10 pages, 8 figures (key result in Figures 7, 8). Accepted for publication in MNRAS. Comments welcom

Degradation and persistence of brestanol in sugarbeet seedlings

Degradation and persistence of a systemic fungicide Brestanol (Triphenyl - tinchloride) known to be effective against Cercospora leaf spot of sugarbeet, was studied in sugarbeet seedlings. Thin layer chromatograms developed with 0.05% sodium fluorescein in methanol was found to be a reliable method for degradation and persistence studies. No degradation of Brestanol occurred in sugarbeet seedlings at 24 hours after treatment, however, it was converted into an entirely different compound with Rf value 0.2, 6 days after spraying. Brestanol sprayed at the rate of 450 ppm was detected at the quantity of 1.125 μg, 4 days after sprayin

Quarantine Important Diseases of Sorghum, Pearl Millet, Chickpea, Pigeonpea and Groununut

Quarantine important diseases of sorghum, pearl millet, chickpea, pigeonpea and groundnut are described. In case of sorghum no report appears to be available on the occurrence of milo, bacterial leaf streak, bacterial leaf blight and bacterial leaf spot in India. Downy mildew, head smut and sugarcane mosaic virus, though found in the country, have quarantine restrictions owing to the fear of their new races being introduced. Downy mildew and ergot, the two serious diseases of pearl millet, are present in India but the entry of seed from the areas where these diseases occur is restricted. Bean yellow mosaic virus of chickpea has not been recorded in India; cucumber mosaic virus, pea leaf roll virus, blight, wilt and alfalfa mosaic virus are present in the country but import of seed from countries where these diseases occur is restricted under quarantine rules. In the case of pigeonpea, anthracnose, bacterial leaf spot and stem canker, sterility mosaic virus and yellow mosaic virus do occur in the country but they too have quarantine restrictions. The exotic diseases of groundnut — scab, Texas root rot, rosette virus, peanut stunt virus, peanut mottle virus and peanut marginal chlorosis virus — and already occurring rust and bacterial wilt, have quarantine importance

Screening of Groundnut Genotypes for Resistance to Kalahasti Malady and Late Leaf Spot Diseases

During 1995-97, 42 genotypes were screened for resistance to kalahasti malady (Tylenchorhynchus brevilineatus) and late leaf spot (Mycosphaerella berkeleyi). Late leaf spot severity was recorded 90 days after sowing on a 1-9 scale while plants were scored for T. brevilineatus infestation at maturity on a 1-5 scale. Only 29 genotypes showed a lower infestation score than the control for T. brevilineatus and all were susceptible to late leaf spot

Small Quadrupole Deformation for the Dipole Bands in 112In

High spin states in $^{112}$In were investigated using $^{100}$Mo($^{16}$O, p3n) reaction at 80 MeV. The excited level have been observed up to 5.6 MeV excitation energy and spin $\sim$ 20$\hbar$ with the level scheme showing three dipole bands. The polarization and lifetime measurements were carried out for the dipole bands. Tilted axis cranking model calculations were performed for different quasi-particle configurations of this doubly odd nucleus. Comparison of the calculations of the model with the B(M1) transition strengths of the positive and negative parity bands firmly established their configurations.Comment: 10 pages, 11 figures, 2 table

Faraday rotation measures of northern-hemisphere pulsars using CHIME/Pulsar

Using commissioning data from the first year of operation of the Canadian Hydrogen Intensity Mapping Experiment's (CHIME) Pulsar backend system, we conduct a systematic analysis of the Faraday Rotation Measure (RM) of the northern hemisphere pulsars detected by CHIME. We present 55 new RMs as well as obtain improved RM uncertainties for 25 further pulsars. CHIME's low observing frequency and wide bandwidth between 400-800 MHz contribute to the precision of our measurements, whereas the high cadence observation provide extremely high signal-to-noise co-added data. Our results represent a significant increase of the pulsar RM census, particularly regarding the northern hemisphere. These new RMs are for sources that are located in the Galactic plane out to 10 kpc, as well as off the plane to a scale height of ~16 kpc. This improved knowledge of the Faraday sky will contribute to future Galactic large-scale magnetic structure and ionosphere modelling.Comment: 13 pages, 7 figures, accepted by MNRA

Frequency and distribution of rare electrophoretic mobility variants in a population of human newborns in Ann Arbor, Michigan

We have summarized the frequency and distribution of the rare variants encountered during the screening of 258 815 allele products, the products of 51 different loci, in 3242 predominantly Caucasian (88 %) newborns. Seventy-nine different rare variants, representing 187 occurrences, were identified. Almost 60 % (46 of 79) of the rare variants occurred as singletons while another 20 % were seen in two unrelated individuals. No rare variants were detected at 18 loci while no variants, either rare or polymorphic, were detected at 14 loci. More rare variants were identified at loci that were classified as polymorphic and also at loci where the gene products exist as a monomer. A positive relationship was observed between variant frequency, either classes or copies, and subunit molecular mass.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65173/1/j.1469-1809.1987.tb01065.x.pd