Grosskraftwerk Mannheim (Germany)

Abstract This paper reports on the latest in a series of projects aiming at the qualification of new and proven materials in components under a severe service environment. In the initial stages of the project (HWT I & HWT II), a test loop at Unit 6 of the GKM Power Plant in Mannheim was used to study the behavior of components for advanced ultra-supercritical (A-USC) plants made from nickel alloys at 725 °C under both static and fluctuating conditions. Due to recent changes in the operation modes of existing coal-fired power plants, the test loop was modified to continue operating the existing nickel components in the static section while applying thermal cycles in a different temperature range. HR6W pipes and valves were added to the bypass of the static section, and all components in the cyclic section were replaced with P92, P93, and HR6W components. The test loop achieved approximately 9000 hours of operation and around 800 cycles with holding times of 4 and 6 hours. After dismantling the loop, nondestructive and destructive examinations of selected components were conducted. The accompanying testing program includes results from thermal fatigue, fatigue, thermal shock, and long-term creep tests, focusing on the behavior of base materials and welds, particularly for HR6W, P92, P93, and other nickel-based alloys. Additionally, test results on dissimilar welds between martensitic steel P92 and nickel alloys A617 and HR6W are presented. Numerical assessments using standardized and numerical lifetime estimation methods complement the investigations. This paper provides insights into the test loop design and operational challenges, material behavior, and lifetime, including advanced numerical simulations and operational experiences with valves, armatures, piping, and welds.

Objective: Randomized trials have shown that concomitant methotrexate (MTX) augments the effectiveness of tumour necrosis factor (TNF) inhibitors in rheumatoid arthritis (RA), but its benefit in psoriatic arthritis (PsA) has not been demonstrated. The goal of this study was to examine whether the impact of concomitant MTX on therapeutic outcomes in patients with PsA was similar to its effects in RA.Methods: We used data from highly comparable and concurrent observational studies of patients with PsA (N = 1424) or RA (N = 3148) who initiated adalimumab therapy during routine clinical care. The 28-joint Disease Activity Score (DAS28) and patient-reported pain scores were evaluated in patients who received 24 months of continuous treatment with adalimumab monotherapy or adalimumab + MTX and in patients who initiated or stopped concomitant MTX during ongoing adalimumab therapy.Results: Twenty-four months of continuous treatment with adalimumab + MTX was superior to adalimumab monotherapy in RA patients, while no significant difference was observed in patients with PsA. RA patients who added MTX during the study showed significant individual improvements in DAS28 and pain scores at 6 months after the change in therapy, while those who removed MTX had slight increases in disease activity. In contrast, in patients with PsA, neither initiation nor removal of MTX during continuous adalimumab therapy had a significant effect on therapeutic outcomes.Conclusion: Addition of MTX to adalimumab confers further therapeutic benefit in patients with RA, but not in those with PsA, suggesting differences in MTX effects in these two patient populations.Clinicaltrials.gov NCT01078090, NCT01077258, NCT01111240

The objective of this work is to study the effect of deposited $$\hbox {CO}_{2}$$ on the solid thermal conductivity of a cryogenic insulation system. Therefore, measurements were performed using a guarded hot plate apparatus at temperatures in the range from 80 K to 290 K in combination with a bellow acting as the sample containment. The unique experimental setup and sample preparation are described in detail. Furthermore, existing thermal models which are based on a superposition of thermal transfer due to radiation and solid thermal conductivity were modified to account for the thermal effects of deposited gases and the consequently increased solid thermal conductivity for a spherical powder. Measurements showed a significant increase of the solid thermal conductivity depending on the amount of $$\hbox {CO}_{2}$$ that was provided for deposition–evacuation. 2.77 Vol-‰ $$\hbox {CO}_{2}$$ resulted in an increase of 5.5 % in the overall solid thermal conductivity. Twice this amount (5.54 Vol-‰ $$\hbox {CO}_{2}$$ ) and four times this amount (11.1 Vol-‰ $$\hbox {CO}_{2}$$ ) resulted in an increase of $$8.8\,\%$$ and 14.1 % in the overall solid thermal conductivity, respectively. Due to additional temperature sensors, it was possible to measure the effective thermal conductivity in different layers of the insulation material. Thus, a significant change in the innermost layer of $$75\,\%$$ was measured for the solid thermal conductivity comparing the evacuated sample with the $$\hbox {CO}_{2}$$ -loaded (11.1 Vol-‰ $$\hbox { CO}_{2})$$ sample.

Was sind auslosende und aufrechterhaltende Bedingungen bei Prufungsangst und wie funktioniert das Yerkes-Dodson-Gesetz? Diese und andere Fragen beantwortet Kapitel 21. Du erhaltst eine Einfuhrung in die vier Ebenen der Prufungsangst: Gedanken, Gefuhle, korperliche Reaktionen und Verhalten. Du erfahrst, was man auf der jeweiligen Ebene gegen die Angst tun kann, z.B. paradoxe Intention, um Angstgedanken zu bearbeiten, Phantasiereisen, um die Stimmung aufzuhellen, Entspannungsmoglichkeiten, um uberschiesende korperliche Reaktionen zu dampfen, und konkrete Verhaltenstipps, um unangemessenem Verhalten in der Prufungssituation vorzubeugen. Und zum Schluss vermitteln wir Strategien zur Vorbeugung und Auflosung eines Blackouts.

Thema des Kapitels sind Ursachen und Erscheinungsformen von Schreibproblemen. Diese ausern sich u.a. als „Angst vor dem leeren Blatt“, als „Aufschieberitis“ – bekanntes Phanomen von epidemischem Ausmas in Studi-Kreisen – und als Schreibblockade im engeren Sinn. Schreibprobleme entstehen oft durch ubersteigerte Anspruche – jeder erstmals zu PC oder Papier gebrachte Satz muss bereits perfekt sein – und durch die (falsche!) Annahme, man musse erst genau wissen, was man schreiben will, um mit dem Schreiben anfangen zu konnen. Wir zeigen dir, wie du diese Probleme in den Griff bekommen kannst, und vermitteln hilfreiche Strategien zur Auflosung von Schreibblockaden wie Free Writing, Worst-Text-Methode, Schreiben mit der nichtdominanten Hand und Clustering.

In diesem Kapitel stellen wir Entspannungsmoglichkeiten bei Lern- und Prufungsstress vor. Wir gehen ausfuhrlich auf klassische Entspannungsmethoden wie Autogenes Training, Progressive Muskelentspannung, Yoga und Meditation ein, die man am besten in einem Kurs mit zertifiziertem Kursleiter erlernt. Andere Techniken wie etwa Phantasiereise und Atementspannung, die du dir selbst beibringen kannst, werden ebenfalls beschrieben und anhand von Beispielen erlautert.

Wir informieren dich daruber, was die Begriffe Bachelor und Master eigentlich bedeuten und welche Bachelorabschlusse und -studiengange es mittlerweile gibt. Wir erklaren dir, was man unter dem Bologna-Prozess versteht und welche Ziele fur Deutschland damit verbunden waren, z.B. Forderung der Mobilitat, Strukturiertheit des Studiums, mehr soziale Gerechtigkeit. Schlieslich fragen wir kritisch, inwieweit diese Ziele bisher erreicht wurden.