Untersuchung atomarer Fehlstellen in verformtem und abgeschrecktem Nickel

1962 ◽  
Vol 17 (3) ◽  
pp. 228-235 ◽  
Author(s):  
Dieter Schumacher ◽  
Wolfgang Schule ◽  
Alfred Seeger

Polycrystalline nickel (purity 99.9% was either cold-rolled below room temperature or quenched from 1000 °C. The recovery of the electrical resistivity was studied between 0 °C °C and 300 °C. After cold-work two separate recovery processes were found in this temperature range (stage III near 80 °C. stage IV near 250 °C with activation energies of 1.09 ± 0.05 ev and 1.55 ± 0.10 ev. respectively.After quenching from 1000 °C only stage IV was present (maximum of the recovery rate near 270 °C, activation energy about 1.5 ev), whereas stage III was not observed. On account of the present results and other available data free interstitial migration is attributed to stage III and the migration of single vacancies to stage IV. We estimate that the energy of formation of single vacancies in nickel is 1.3 — 1.4 ev, and that the volume increase per vacancy is 0.82 atomic volumes.

2011 ◽  
Vol 702-703 ◽  
pp. 402-405
Author(s):  
Nobuhiro Tsuji ◽  
Yoshihiro Takatsuji ◽  
Yoji Miyajima ◽  
Pinaki Prasad Bhattacharjee ◽  
Daisuke Terada

A pure Ni sheet was heavily deformed up to an equivalent strain of 6.4 at room temperature and then annealed to obtain highly Cube textured material, which is a polycrystal subdivided by many low-angle grain boundaries. The highly Cube-oriented sheets were cold-rolled to various reductions up to 90%. It was found that large fraction of Cube oriented grains remained stable in cold-rolling although the orientation is theoretically unstable. The stability of Cube orientation was considered to be associated with the constraint by grain boundaries in the materials.


Author(s):  
Maria Cristina Fortuna ◽  
Henk Hoekstra ◽  
Benjamin Joachimi ◽  
Harry Johnston ◽  
Nora Elisa Chisari ◽  
...  

Abstract Intrinsic alignments (IAs) of galaxies are an important contaminant for cosmic shear studies, but the modelling is complicated by the dependence of the signal on the source galaxy sample. In this paper, we use the halo model formalism to capture this diversity and examine its implications for Stage-III and Stage-IV cosmic shear surveys. We account for the different IA signatures at large and small scales, as well for the different contributions from central/satellite and red/blue galaxies, and we use realistic mocks to account for the characteristics of the galaxy populations as a function of redshift. We inform our model using the most recent observational findings: we include a luminosity dependence at both large and small scales and a radial dependence of the signal within the halo. We predict the impact of the total IA signal on the lensing angular power spectra, including the current uncertainties from the IA best-fits to illustrate the range of possible impact on the lensing signal: the lack of constraints for fainter galaxies is the main source of uncertainty for our predictions of the IA signal. We investigate how well effective models with limited degrees of freedom can account for the complexity of the IA signal. Although these lead to negligible biases for Stage-III surveys, we find that, for Stage-IV surveys, it is essential to at least include an additional parameter to capture the redshift dependence.


1994 ◽  
Vol 4 (1) ◽  
pp. 66-71
Author(s):  
B. D. Evans ◽  
P. Chapman ◽  
P. Dady ◽  
G. Forgeson ◽  
D. Perez ◽  
...  

Fifty-six patients with ovarian cancer (three stage IC, nine stage II, 33 stage III and II stage IV) were treated with carboplatin 350 mg m−2 i.v. day 1 and chlorambucil orally 0.15 mg kgm−1 days 1–7 inclusive, repeated every 28 days for eight courses. The regimen was well tolerated and was virtually free of nephro- and neurotoxicity. Grade III or IV hematology toxicity occurred in 18 patients but only 31 or 330 courses administered were delayed. Of 40 assessable patients eight achieved a clinical/radiologic complete response and 17 a clinical/radiologic partial response. Actuarial survival at 50 months was 65% for stage II patients, 27% for stage III patients and no stage IV patients survived beyond 20 months. Forty-two per cent of patients with residual disease less 2 cm survived 50 months, compared with 44% of patients with moderate volume (2–5 cm) residual disease and 6% of patients with bulk residual disease. This is an active, well tolerated regimen. However, only patients with small volume residual disease have a significant chance of prolonged survival.


1984 ◽  
Vol 84 (6) ◽  
pp. 845-859 ◽  
Author(s):  
D S Dennison ◽  
W Shropshire

The gravitropism of a mature stage IV Phycomyces sporangiophore has a shorter and more uniform latency if the sporangiophore is exposed horizontally to gravity during its earlier development (stage II and stage III). This early exposure to an altered gravitational orientation causes the sporangiophore to develop a gravireceptor as it matures to stage IV and resumes elongation. A technique has been developed to observe the spatial relationship between the vacuole and the protoplasm of a living sporangiophore and to show the reorganization caused by this exposure to altered gravity. Possible gravireceptor mechanisms are discussed.


Author(s):  
Hakan Ozaltun ◽  
Samuel J. Miller

This article aims to provide possible mechanical causes for the lowered blister temperatures of RERTR-12 and AFIP-4 fuel plates. Recent experimental investigations to determine the blister threshold temperatures have indicated lower thresholds for similar plates with comparable burn-up histories. Measured blister temperatures of roughly 100 °C lower compared to the previously tested plates may not be satisfactory for some plates. The primary differences between recent experiments and previous tests are: (1) An aggressive cold work process involving large thickness reduction ratios without normalization or full annealing (2) Subjecting the plates to a thermal cycling process prior to irradiation, and finally (3) A primarily frontal neutron flux as opposed to a transverse flux profile. It is believed that the stress field has implications to blister behavior. To investigate this claim, the stress-strain states for the fabrication procedure were evaluated. First, the residual stress profile caused by the cold rolling process was calculated. Modeling of the cold rolling process has shown confirmation of residual stresses of considerable magnitude and the existence of stress gradients with respect to foil thickness prior to the HIP process. Once calculated, these stress profiles were used as an initial condition for the fabrication process. Due to the variation in stress fields depending on location at which a foil is cut from the cold rolled plate, three representative regions were selected and implemented in the HIP simulation. Variation in stresses, depending on location of the cold rolled plate as well and variation in the through-thickness, results in a wide range of mechanical stress states. This suggests that inhomogeneous irradiation and thermal cycling behavior will result from the use of cold rolled foils. Additionally, these results suggest that there will be fundamental differences in fuel plate behavior observed between plates fabricated with cold rolled foils versus hot rolled and fully annealed foils.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A327-A327
Author(s):  
Lexy Adams ◽  
Robert Chick ◽  
Guy Clifton ◽  
Timothy Vreeland ◽  
Patrick McCarthy ◽  
...  

BackgroundThe tumor lysate, particle-loaded, dendritic cell (TLPLDC) vaccine is created ex vivo by loading autologous dendritic cells (DC) with yeast cell wall particles (YCWP) containing autologous tumor lysate, thus delivering tumor antigens to the DC cytoplasm via phagocytosis. TLPLDC then activates a robust T cell response against the unique antigens for each patient. The primary analysis of the prospective, randomized, multi-center, double-blind, placebo-controlled phase IIb trial in patients with resected stage III/IV melanoma showed TLPLDC improved 24-month disease-free survival (DFS) in the per-treatment (PT) analysis (patients completing the 6-month primary vaccine series). Here, we examine the secondary endpoint of 36-month DFS and overall survival (OS).MethodsPatients with resected stage III/IV melanoma were randomized 2:1 to TLPLDC vaccine or placebo (autologous DC loaded with empty YCWP). Treatments were given at 0, 1, 2, 6, 12 and 18 months. The protocol was amended to include patients receiving concurrent checkpoint inhibitors (CPIs) to follow changes in standard of care. The co-primary endpoints were 24-month DFS by intention-to-treat (IT) analysis and per-treatment (PT) analysis, with secondary endpoints including 36-month DFS and OS by ITT and PT analysis, pre-specified analysis by stage, and safety as measured by CTCAE v4.03.ResultsOverall, 103 patients received TLPLDC and 41 placebo. In PT analysis, 65 patients received TLPLDC and 32 placebo. Total adverse events (AEs), grade 3+ AEs, and serious AEs (SAEs) were similar in placebo vs TLPLDC groups, with one related SAE per treatment arm. By ITT analysis, 36-month OS was 76.2% for TLPLDC vs 70.3% for placebo (HR 0.72, p=0.437) and 36-month DFS was 35.6% vs 27.1% (HR 0.95, p=0.841). By PT analysis, 36-month DFS was improved with TLPLDC (57.5% vs 35.0%; HR 0.50, p=0.025, figure 1). This effect was even more dramatic in resected stage IV patients (36-month DFS: 60.9% vs 0%; HR 0.12, p=0.001, figure 2).ConclusionsThis phase IIb trial again demonstrates the safety of the TLPLDC vaccine, and an improved 36-month DFS in patients with resected stage III/IV melanoma who complete the primary vaccine series, particularly in the stage IV subgroup. Next, a phase III trial will evaluate the efficacy of TLPLDC vaccine as adjuvant treatment for resected stage IV melanoma, with patients randomized to receive standard of care PD-1 inhibitors + TLPLDC versus PD-1 inhibitors + placebo.Abstract 300 Figure 136-month disease free survival for patients receiving TLPLDC vs placebo by PT analysisAbstract 300 Figure 236-month disease free survival for subset of stage IV melanoma patients receiving TLPLDC vs placebo by PT analysisTrial RegistrationThis is a phase IIb clinical trial registered under NCT02301611Ethics ApprovalThis study was approved by Western IRB, protocol 20141932.


Author(s):  
Sung Hwan Kim ◽  
Chaewon Kim ◽  
Changheui Jang

Diffusion bonding was conducted on cold-worked Alloy 600. Cold-work of 50 % was applied prior to diffusion bonding in order to incite recrystallization and limit grain growth. Tensile testing was conducted at room temperature and 550 °C for evaluation of joint efficiency, while premature brittle failure at the bond-line was observed for most diffusion bonding conditions. It was found that such premature failure was related to a planar bond-line that indicated lack of grain boundary diffusion across the bonding surfaces. Additional application of post-bond heat treatments did not result in significant bond-line migration. Microstructural analyses revealed the existence of Cr-rich carbides and Ti-rich precipitates along the bond-line, which prevented bond-line migration by acting as pinning points.


2014 ◽  
Vol 32 (1) ◽  
pp. 5-8
Author(s):  
M Mazumder ◽  
A Islam ◽  
N Farooq ◽  
M Zaman

Introduction: Wilms’ tumor is the most common primary malignant renal tumor of childhood. It is important to pick up the children with wilms’ tumor earlier as early stages has excellent outcomes after treatment. Objective : To find out the common clinical presentations and pathological profile of Wilms’ tumor in children. Methods and Materials : A hospital based prospective study done with twenty diagnosed patients of Wilms tumour enrolled from department of Pediatric haemato-oncology, BSMMU, Dhaka in the period between January to December 2008. Results- The peak incidence of Wilms’ tumor was in 1 to 5 years age group (80%,n=16). Median age at presentation was 49 months with male: female ratio 1.8:1.The most common presentation was abdominal swelling (80%,n=16),followed by flank mass (75%,n=15), abdominal pain (55%,n=11), haematuria (15%,n=3), hypertension (10%,n=2). Thirteen raised from right kidney, ratio of right to left involvement 1.8:1. Histologically 13(65%) patients had triphasic histology having blastemal, stromal and epithelial elements, 7(35%) was biphasic having blastema and epithelia. All had favourable histological pattern. Most patients presented in stage III (55%,n=11) followed by stage II (25%,n=5), Stage IV(10%,n=2), Stage I(10%,n=2). No bilateral presentation. Conclusions : Most of the patients of Wilms’ tumor presented within 1 to 5 years of age(80%) with abdominal distension(80%) and flank mass(75%), few associated with haematuria(15%) and hypertension(10%). Histologically all were favourable and maximum presented in stage III (55%) followed by stage II(25%). DOI: http://dx.doi.org/10.3329/jbcps.v32i1.21015 J Bangladesh Coll Phys Surg 2014; 32: 5-8


1997 ◽  
Vol 18 (7) ◽  
pp. 418-423 ◽  
Author(s):  
Alberto Branca ◽  
Luigi Di Palma ◽  
Carmelo Bucca ◽  
Camilla Sagarriga Visconti ◽  
M. Di Mille

Ankle arthroscopy has recently allowed the elaboration of less invasive techniques for the treatment of anterior impingement. Its indications, advantages, and drawbacks in this application are discussed. Between 1987 and 1994, 133 patients were treated for ankle impingement. Among them, 58 patients, 37 men and 21 women (mean age, 28.5 years), who had failed a trial of conservative treatment were treated by means of tibiotalar arthroscopy. Twenty-seven were athletes engaged in sports with abnormal stressing of the ankle. According to McDermott's radiological classification, there were 15 stage I cases, 23 stage II, 13 stage III, and 7 stage IV. Preoperative evaluation with a modified version of McGuire's scoring system gave 50 cases rated as “poor” (<60 points) and 8 cases rated as “fair” (60–67 points). Treatment consisted of removal of adhesions, cartilage shaving, and removal of the bone impingement with powered instruments, curettes, or small osteotomes. Follow-up was from 8 to 62 months (mean, 21.5 months). The postoperative McGuire ratings were 37 good, 13 fair, and 8 poor. There were no major complications. Recurrence of impingement was observed in four cases of stage III and IV. The conclusion is drawn that ankle arthroscopy is a sound method for the treatment of anterior impingement. Even in cases with severe joint cartilage impairment, it plays a therapeutic role as a means of postponing a possible arthrodesis.


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