Status of light weight cassette design of SOFC

Lightweight SOFC stacks are currently being developed especially for automotive applications such as APU and for portable devices. Within the EU funded project MMLCR=SOFC the Jülich lightweight so-called CS-design was improved concerning better suitability for glass sealing, reduced manufacturing effort and increased power. Based on modelling in combination with manufacturing experience, test results, and post-test analysis substantial changes of the previous CS-design were made. The manufacturing of single parts, particularly due to the improved design of sheet metal interconnects, as well as the assembling processes are suitable for low-cost mass manufacturing. The novel decal concept of glass-ceramic sealant screen printed on foil in order to produce green tapes is used for joining the stack layers offering an enormous potential for cost savings in industrial assembly process. First stack tests with the new CSV–design showed a comparable electrochemical performance to the previous CSIV design having at the same time a better thermo-mechanical behavior.</jats:p

Повышение эффективности использования аварийно-спасательного оборудования

Объектом исследования является работа двигателей внутреннего сгорания в условиях содержания в атмосфере продуктов горения, и с низким содержанием кислорода. Система функционирования аварийно-спасательного оборудования, оснащенного двигателями внутреннего сгорания в критических условиях задымленных помещений. Цель работы – Повышение эффективности аварийно-спасательного оборудования, оснащенного двигателями внутреннего сгорания. В процессе исследования проводились натурные полигонные испытания устройства подачи воздуха в двигатель внутреннего сгорания, с составлением акта технического освидетельствования. В результате исследования поставленная цель - повышение эффективности аварийно-спасательного оборудования, оснащенного двигателями внутреннего сгорания, достигнута.The object of research is the operation of internal combustion engines under conditions of combustion products in the atmosphere and with a low oxygen content. The functioning system of emergency equipment equipped with internal combustion engines in critical conditions of smoky rooms. Purpose of work - Improving the efficiency of emergency equipment equipped with internal combustion engines. In the course of the study, field tests of the device for supplying air to the internal combustion engine were carried out, with the drawing up of an act of technical inspection. As a result of the study, the goal - to increase the efficiency of emergency equipment equipped with internal combustion engines, has been achieved

Barium Borosilicate Sealing Glasses Synthesized by a Sol-Gel Process: Chemical Interactions with a Stainless Steel and Gas-Tightness of a SOFC

Abstract Several glasses synthesized by sol-gel route and based on the BaO-B2O3-X-Al2O3-SiO2 (X=CaO, MgO) glass system have been investigated to evaluate their applicability as sealant for solid oxide fuel cell (SOFC). Chemical interactions with K41X stainless steel and hydrogen-tightness of these materials were evaluated after operations at high temperatures over 1,000h in air atmosphere. Formation of a new phase at the steel?glass interface and formation of porosity in the glass were observed and determined as critical problems over mid-term operations. The role of MgO is important to obtain a gas-tight sealing. Application of the glass paste without binder addition was performed in order to avoid possible residual porosity related problems. The best glass was finally used as sealant between anodic and cathodic compartments in complete SOFCs operated at 760 and at 800°C. Open circuit voltages and power densities of the cells were recorded during the first hours of operation

C-reactive protein for diagnosing late-onset infection in newborn infants

BACKGROUND: Late-onset infection is the most common serious complication associated with hospital care for newborn infants. Because confirming the diagnosis by microbiological culture typically takes 24 to 48 hours, the serum level of the inflammatory marker C-reactive protein (CRP) measured as part of the initial investigation is used as an adjunctive rapid test to guide management in infants with suspected late-onset infection. OBJECTIVES: To determine the diagnostic accuracy of serum CRP measurement in detecting late-onset infection in newborn infants. SEARCH METHODS: We searched electronic databases (MEDLINE, Embase, and Science Citation Index to September 2017), conference proceedings, previous reviews, and the reference lists of retrieved articles. SELECTION CRITERIA: We included cohort and cross-sectional studies evaluating the diagnostic accuracy of serum CRP levels for the detection of late-onset infection (occurring more than 72 hours after birth) in newborn infants. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed eligibility for inclusion, evaluated the methodological quality of included studies, and extracted data to estimate diagnostic accuracy using hierarchical summary receiver operating characteristic (SROC) models. We assessed heterogeneity by examining variability of study estimates and overlap of the 95% confidence interval (CI) in forest plots of sensitivity and specificity. MAIN RESULTS: The search identified 20 studies (1615 infants). Most were small, single-centre, prospective cohort studies conducted in neonatal units in high- or middle-income countries since the late 1990s. Risk of bias in the included studies was generally low with independent assessment of index and reference tests. Most studies used a prespecified serum CRP threshold level as the definition of a 'positive' index test (typical cut-off level between 5 mg/L and 10 mg/L) and the culture of a pathogenic micro-organism from blood as the reference standard.At median specificity (0.74), sensitivity was 0.62 (95% CI 0.50 to 0.73). Heterogeneity was evident in the forest plots but it was not possible to conduct subgroup or meta-regression analyses by gestational ages, types of infection, or types of infecting micro-organism. Covariates for whether studies used a predefined threshold or not, and whether studies used a standard threshold of between 5 mg/L and 10 mg/L, were not statistically significant. AUTHORS' CONCLUSIONS: The serum CRP level at initial evaluation of an infant with suspected late-onset infection is unlikely to be considered sufficiently accurate to aid early diagnosis or select infants to undergo further investigation or treatment with antimicrobial therapy or other interventions

Versprödung von Metallen bei hohen Temperaturen (T ≤\leq 0.45 TM_{M}) durch Helium

High temperature helium embrittlement, swelling and irradiation creep are the main technical problem of $\underline{fusion}$ $\underline{reactor}$ $\underline{materials}$. The expected helium production will be very high. The helium produced by (n, $\alpha$)-processes precipitates into heliumbubbles because its solubility in solid metals is very low. Under continuous helium production at high temperature and stress the helium bubbles grow and lead to intergranular early failure. Solution annealed foil specimens of austenitic stainless steel AISI 316 were implanted with a-particles: (1) during creep tests at 1023 K ("in-beam" test) (2) before the creep tests at high temperature (1023 K). The creep tests have been performed within large ranges of test parameter, e. g. applied stress, temperature, helium implantation rate and helium concentration. After the creep tests the microstructure was investigated using scanning (SEM) and transmission (TEM) electron microscopy. All the helium implanted specimens showed high temperature helium embrittlement, i. e. reduction of rupture time t$_{R}$ and ductility $\epsilon$$_{R}$ and evidence of intergranular brittle fracture. The "in-beam" creep tests showed greater reduction of rupture time t$_{R}$ and ductility than the preimplanted creep tests. The comparison of this experimentally obtained data with various theoretical models of high temperature helium embrittlement showed that within the investigated parameter ranges the mechanism controlling the life time of the samples is probably the gas driven stable growth of the helium bubbles within the grain boundaries