29 research outputs found

    Contribution to the thermal properties of selected steels

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    The paper deals with the influence of structural changes on heat transport phenomena of steels samples. Three samples of 10GN2MFA steel were thermally treated at quenching temperatures equal to 900 °C, 1 000 °C and 1 100 °C, and temperature of the tempering was 670 °C. Both thermal diffusivity and thermal conductivity increase with the quenching temperature. Specific heat capacity of steel samples after thermal treatment does not change significantly. Further three different high manganese steels were measured. Maximal content of Mn and C was 27 and 0,5 mass percent. From results of thermophysical properties after ageing, one can see the increase of thermal diffusivity up to 20 percent, thermal conductivity up to 15 percent, decrease of specific heat capacity is not significant. All measured values of thermophysical properties are in good agreement with literary data (before ageing)

    A phase 2 study of ibrutinib in combination with bortezomib and dexamethasone in patients with relapsed/refractory multiple myeloma

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    Objective: We evaluated ibrutinib, a once-daily inhibitor of Bruton's tyrosine kinase, combined with bortezomib and dexamethasone in patients with relapsed or relapsed/refractory multiple myeloma who had received 1-3 prior therapies. Methods: This was a phase 2, single-arm, open-label, multicentre study (NCT02902965). The primary endpoint was progression-free survival (PFS). Results: Seventy-six patients were enrolled; 74 received ≥1 dose of study treatment. After median follow-up of 19.6 months, median PFS was 8.5 months (95% CI: 6.2-10.8); median overall survival was not reached. Overall response rate was 57% (95% CI: 45-68), and median duration of response was 9.5 months (95% CI: 6.9-10.6). Grade 3/4 AEs occurred in 73% of patients and fatal AEs occurred in 15% of patients. Incidence of major haemorrhage was 5%; one patient died from cerebral haemorrhage. After an observed increased incidence of serious (42%) and fatal (11%) infections, enrolment was suspended to implement risk-minimisation measures. The safety profile was otherwise consistent with known safety profiles of the individual drugs. Conclusion: Ibrutinib combined with bortezomib and dexamethasone elicited clinical responses. However, efficacy assessments conducted at potential restart of enrolment indicated that the targeted PFS could not be reached with additional patient enrolment, and the study was terminated

    Quantum kinetics and thermalization in a particle bath model

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    We study the dynamics of relaxation and thermalization in an exactly solvable model of a particle interacting with a harmonic oscillator bath. Our goal is to understand the effects of non-Markovian processes on the relaxational dynamics and to compare the exact evolution of the distribution function with approximate Markovian and Non-Markovian quantum kinetics. There are two different cases that are studied in detail: i) a quasiparticle (resonance) when the renormalized frequency of the particle is above the frequency threshold of the bath and ii) a stable renormalized `particle' state below this threshold. The time evolution of the occupation number for the particle is evaluated exactly using different approaches that yield to complementary insights. The exact solution allows us to investigate the concept of the formation time of a quasiparticle and to study the difference between the relaxation of the distribution of bare particles and that of quasiparticles. We derive a non-Markovian quantum kinetic equation which resums the perturbative series and includes off-shell effects. A Markovian approximation that includes off-shell contributions and the usual Boltzmann equation (energy conserving) are obtained from the quantum kinetic equation in the limit of wide separation of time scales upon different coarse-graining assumptions. The relaxational dynamics predicted by the non-Markovian, Markovian and Boltzmann approximations are compared to the exact result. The Boltzmann approach is seen to fail in the case of wide resonances and when threshold and renormalization effects are important.Comment: 39 pages, RevTex, 14 figures (13 eps figures

    Wykorzystanie matematycznych i fizycznych modeli niedziałających w czasie rzeczywistym do optymalizacji procesu nagrzewania

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    Heating of materials is energy and costly operations. On those reasons optimization is highly desirable. One of the possible solutions to optimize heating in real time is to use a large number of fast simulations on the basis of them the optimization algorithms have chosen the most appropriate option of the heating control. This solution implies the use of extremely fast but sufficiently accurate simplified mathematical models of heating, the structure and parameters of them are defined based on accurate modelling using computationally intensive but slower classical mathematical-physical models. Based on the operating data of the reheating furnace was build an accurate model of heating. Using the simplified model simulation of heating was done with different heating conditions with downtime during heating. Proposed algorithms including the simulations show that the proposed strategy leads to verifiable savings during heating.Nagrzewanie materiałów jest procesem energochłonnym i kosztowny. Dlatego optymalizacja tych procesów jest bardzo pożądana. Jednym z rozwiązań umożliwiających optymalizacje nagrzewania w czasie rzeczywistym jest przeprowadzenie dużej liczby szybkich symulacji, na podstawie których algorytmy optymalizacji wybierały najodpowiedniejszą wersję sterowania nagrzewaniem. Rozwiązanie takie zakłada stosowanie niezwykle szybkich ale wystarczająco dokładnych uproszczonych matematycznych modeli nagrzewania, których struktura i parametry określane są na podstawie dokładnych, ale wolno działających klasycznych modeli matematyczno-fizycznych. Na podstawie danych eksploatacyjnych pieca grzewczego zbudowano model dokładny, a następnie korzystając z jego wersji uproszczonych przeprowadzono symulacje dla różnych warunków nagrzewania uwzględniając przestoje w trakcie nagrzewania. Zaproponowane algorytmy wraz z wynikami symulacji pokazują, że proponowane podejście prowadzi do znaczących oszczędności w trakcie nagrzewania

    Carfilzomib, lenalidomide, and dexamethasone in patients with relapsed multiple myeloma categorised by age: secondary analysis from the phase 3 ASPIRE study

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    A primary analysis of the ASPIRE study found that the addition of carfilzomib to lenalidomide and dexamethasone (carfilzomib group) significantly improved progression-free survival (PFS) compared with lenalidomide and dexamethasone alone (control group) in patients with relapsed multiple myeloma (RMM). This post hoc analysis examined outcomes from ASPIRE in patients categorised by age. In the carfilzomib group, 103/396 patients were ≥70 years old, and in the control group, 115/396 patients were ≥70 years old. Median PFS for patients <70 years old was 28·6 months for the carfilzomib group versus 17·6 months for the control group [hazard ratio (HR), 0·701]. Median PFS for patients ≥70 years old was 23·8 months for the carfilzomib group versus 16·0 months for the control group (HR, 0·753). For patients <70 years the overall response rate (ORR) was 86·0% (carfilzomib group) and 66·9% (control group); for patients ≥70 years old the ORR was 90·3% (carfilzomib group) and 66·1% (control group). Within the carfilzomib group, grade ≥3 cardiovascular adverse events occurred more frequently among patients ≥70 years old compared with patients <70 years old. Carfilzomib-lenalidomide-dexamethasone has a favourable benefit-risk profile for patients with RMM, including elderly patients ≥70 years old. Trial Registration: clinicaltrials.gov identifier: NCT01080391. © 2017 The Authors. British Journal of Haematology published by John Wiley & Sons Ltd
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