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Microstructural Evolution and Thermal Stability of Ultra-fine Grained Al-4Mg Alloy by Equal Channel Angular Pressing
Hongbin GENG,Subbong KANG,Shiyu HE,
Hongbin GENG
,Subbong KANG,Shiyu HE School of Materials Science and Engineering,Harbin Institute of Technology Harbin,China Korea Institute of Machinery and Materials,Sangnam Dong,Changwon,Kyungnam -,South Korea

材料科学技术学报 , 2004,
Abstract: Experiments were conducted to evaluate the grain refinement and thermal stability of ultra-fine grained Al-4Mg alloy introduced by equal-channel angular pressing (ECAP) at 473 K. The results show that the intensities of X-ray (111/222) and (200/400) peaks for the alloy processed by ECAP decrease significantly and the peak widths of half height become broadening compared with the corresponding value in the annealed alloy. The microstructure of 2 passes ECAPed alloy consists of both elongated and equiaxed subgrains. The residual strain in the alloy increases with increasing passes numbers, that appears as increasing dislocation density and lattice constant of matrix. An equiaxed ultra-fine grained structure of ~0.2μm is obtained in the present alloy after 8 passes. The ultra-fine grains are stable below 523 K, because the alloy retains extremely fine grain size of ~1μm after static annealing at 523 K for1 h.
Pattern of Cardiac Trauma in Sulaimani Province of Southern Kurdistan: 5 Years’ Experience  [PDF]
Aram Baram, Goran Majeed, Hewa Sherzad, Ftoon Flah Korea, Rzgar Ghareeb Muhamed, Fahmi H. Kakamad
World Journal of Cardiovascular Surgery (WJCS) , 2015, DOI: 10.4236/wjcs.2015.58014
Abstract: Introduction: Cardiac injuries are one of the important causes of death in young population. With aggressive resuscitative therapy and emergency room thoracotomy, the salvage rate of these patients can reach 35%. In this case series the types of presentation, methods of resuscitation, surgical approaches, operative and postoperative outcomes are discussed. Patients and Methods: From January 2009 to January 2014 there were 3157 patients treated for thoracic injuries at Sulaimani university hospital, 14 patients had cardiac injuries. All admitted cases with central chest trauma were submitted to a thorough clinical examination, ECG and eFAST (extended Focused assessment with sonography for trauma) and/or transthoracic echocardiography. Results: Total of 14 cardiac injuries from 3157 causalities were identified, which is 0.44% of the total admissions. Male gender was predominant (85.7% vs. 14.28%) for females. Mechanism of injury was mostly penetrating (85.71%) among which stabs were majority (57.14%) while bullet and shrapnel each constituted (14.28%). Mean time of interval between the accident and our intervention was 2.96 hours. No diagnostic test was 100% specific and sensitive. Discussion: Cardiac injury regarded as a crucial injury because of its high fatality. It is reported that 10.3% of emergency surgical operations are thoracic type and about 1% of them are associated with cardiac injury. Although any penetrating injury to the thorax may injure the heart but those within the box are more suspicious. We conclude that cardiac trauma is a fatal injury but still if the facilities are available the mortality can be minimized.
Searches for New Physics at HERA
David South
Physics , 2006,
Abstract: The latest results from the H1 and ZEUS collaborations are presented on rare Standard Model processes and searches for physics Beyond the Standard Model. Intriguing events containing high transverse momentum leptons are observed by H1 and many competitive limits are set by both collaborations on the production of new particles in a variety of supersymmetry scenarios.
New H1 results on isolated leptons and missing pt at HERA
D. South
Physics , 2006,
Abstract: The search for events containing isolated leptons (electrons or muons) and missing transverse momentum produced in $e^{\pm}p$ collisions is performed with the H1 detector at HERA in the period 1994--2005. The analysed data sample corresponds to an integrated luminosity of 279 pb$^{-1}$, which includes 53 pb$^{-1}$ of $e^{+}p$ data and 107 pb$^{-1}$ of $e^{-}p$ data from the new HERA~II phase. A total of 40 events are observed in the data, compared to a Standard Model (SM) prediction of 34.3 $\pm$ 4.8. At large hadronic transverse momentum $P_{T}^{X} >$ 25 GeV, a total of 17 events are observed compared to 9.0 $\pm$ 1.5 predicted by the SM. In this region, 15 events are observed in the $e^{+}p$ data compared to a SM prediction of 4.6 $\pm$ 0.8, whereas in the $e^{-}p$ data 2 events are observed compared to a SM prediction of 4.4 $\pm$ 0.7.
ASSESSMENT OF DAMAGE AND LIFE PREDICTION OF AUSTENITIC STAINLESS STEEL UNDERHIGH TEMPERATURE FATIGUE CREEP INTERACTION CONDITION
SWNam Deptof Materials Science,Engineering,Korea Adv Instof Sciand Tech Gusong dong,Yusong gu,Taejon,korea,
S.W.Nam Dept.of Materials Science and Engineering
,Korea Adv .Inst.of Sci.and Tech . Gusong dong,Yusong gu,Taejon,korea

金属学报(英文版) , 1999,
Abstract: Itis understood that grain boundary cavitation is one of the detrimental processes for thedegradation of materials that reduces the creep fatigue life at high temperatures. Anewdamagefunction based on a modelforthecreep fatiguelife prediction in termsof nucleationand growth ofgrain boundarycavitiesisproposed. Thisdamagefunctionisacombination ofthetermsrelated to the cavitational damagein thelife prediction equation and is generallyapplicabletothe materialsin which failureis controlled by the grain boundary cavitationaldamage. Thecreep fatiguedatafrom thepresentandotherinvestigationsareusedtocheckthevalidityofthe proposed function, and itisshown thattheysatisfythereliability of damagefunction. Additionally, using this damage function, one may realize that allthe Coffin Manson plotsatthevariouslevelsoftensileholdtimeandtemperatureunderstrain controlled creep fatiguetestscan be normalizedto makethe mastercurve.
Female-Biased Dispersal and Gene Flow in a Behaviorally Monogamous Mammal, the Large Treeshrew (Tupaia tana)
Jason Munshi-South
PLOS ONE , 2008, DOI: 10.1371/journal.pone.0003228
Abstract: Background Female-biased dispersal (FBD) is predicted to occur in monogamous species due to local resource competition among females, but evidence for this association in mammals is scarce. The predicted relationship between FBD and monogamy may also be too simplistic, given that many pair-living mammals exhibit substantial extra-pair paternity. Methodology/Principal Findings I examined whether dispersal and gene flow are female-biased in the large treeshrew (Tupaia tana) in Borneo, a behaviorally monogamous species with a genetic mating system characterized by high rates (50%) of extra-pair paternity. Genetic analyses provided evidence of FBD in this species. As predicted for FBD, I found lower mean values for the corrected assignment index for adult females than for males using seven microsatellite loci, indicating that female individuals were more likely to be immigrants. Adult female pairs were also less related than adult male pairs. Furthermore, comparison of Bayesian coalescent-based estimates of migration rates using maternally and bi-parentally inherited genetic markers suggested that gene flow is female-biased in T. tana. The effective number of migrants between populations estimated from mitochondrial DNA sequence was three times higher than the number estimated using autosomal microsatellites. Conclusions/Significance These results provide the first evidence of FBD in a behaviorally monogamous species without mating fidelity. I argue that competition among females for feeding territories creates a sexual asymmetry in the costs and benefits of dispersal in treeshrews.
Search for Lepton Flavour Violation at HERA
South, David M.
High Energy Physics - Phenomenology , 2013,
Abstract: A search for second and third generation scalar and vector leptoquarks produced in ep collisions via the lepton flavour violating processes ep -> mu X and ep -> tau X is performed by the H1 experiment at HERA. The full H1 ep data sample taken at a centre-of-mass energy of 319 GeV is used for the analysis. No evidence for the production of such leptoquarks is observed in the H1 data. Leptoquarks produced in ep collisions with a coupling strength of 0.3 and decaying with the same coupling strength to a muon-quark pair or a tau-quark pair are excluded at 95% confidence level up to leptoquark masses of 712 GeV and 479 GeV, respectively.
Search for First Generation Leptoquarks in ep Collisions at HERA
South, David M.
High Energy Physics - Phenomenology , 2013,
Abstract: A search for first generation scalar and vector leptoquarks produced in ep collisions is performed by the H1 Collaboration at HERA. The full H1 data sample is used in the analysis, corresponding to an integrated luminosity 446 pb^-1. No evidence for the production of leptoquarks is observed in final states with a large transverse momentum electron or with large missing transverse momentum, and constraints on leptoquark models are derived. For leptoquark couplings of electromagnetic strength lambda=0.3, first generation leptoquarks with masses up to 800 GeV are excluded at 95% confidence level.
Search for Lepton Flavour Violation at HERA
South, David M.
High Energy Physics - Phenomenology , 2013,
Abstract: A search for second and third generation scalar and vector leptoquarks produced in ep collisions via the lepton flavour violating processes ep to mu-X and ep to tau-X is performed by the H1 Collaboration at HERA. The full H1 ep data sample taken at a centre-of-mass energy of 319 GeV is used for the analysis, corresponding to an integrated luminosity of 411 pb^-1. No evidence for the production of such leptoquarks is observed in the H1 data. Leptoquarks produced in ep collisions with a coupling strength of lambda=0.3 and decaying with the same coupling strength to a muon-quark pair or a tau-quark pair are excluded at 95% confidence level up to leptoquark masses of 712 GeV and 479 GeV, respectively.
Data Preservation and Long Term Analysis in High Energy Physics
David M. South
Physics , 2009,
Abstract: High energy physics data is a long term investment and contains the potential for physics results beyond the lifetime of a collaboration. Many existing experiments are concluding their physics programs, and looking at ways to preserve their data heritage. Preservation of high-energy physics data and data analysis structures is a challenge, and past experience has shown it can be difficult if adequate planning and resources are not provided. A study group has been formed to provide guidelines for such data preservation efforts in the future. Key areas to be investigated were identified at a workshop at DESY in January 2009, to be followed by a workshop at SLAC in May 2009. More information can be found at http://dphep.org
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