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91.
A. Hofmann 《低温学》2006,46(11):825-830
It is a normal operating condition for a lot of cryogenic storage vessels that no boil-off gas is vented over long periods, which leads to a simultaneous pressure increase of the stored fluid. One main reason therefore is to avoid product losses during transport or between withdrawals. At transport conditions the mixing of the fluid can be assumed to be ideally, which results in a maximum reachable pressurising period. At stationary conditions the pressurising period is expected to be shorter, because a stratification is rising up, so that the heat capacity of the stored fluid cannot be used completely.In a thermodynamic view, an isochore change of state takes place and the heat flux into the vessel rises the internal energy of the fluid. For the representation of the isochore change of state a new developed Δu/v-v-diagram with the 1 × 105 Pa reference as a basis line is introduced. The basis line is linear for the filling rate and functionally connected with the specific volume.For the fluids He and H2 e.g., Δu/v-v-diagrams are pointed out, using the u- and v-values on the saturation lines for the two phase region and those of some isobar lines for the region above the critical pressure. 相似文献
92.
H. Hofmann D. Mattissen T. W. Schaumann 《Materialwissenschaft und Werkstofftechnik》2006,37(9):716-723
Advanced multiphase steels offer a great potential for bodies‐in‐white through their combination of formability and achievable component strength levels. They are first choice for strength and crash‐relevant parts of challenging geometry. The intensive development of high‐strength multiphase steels by ThyssenKrupp has led to hot dip galvanizing concepts with an outstanding forming potential. Hot rolled, hot dip galvanized complex phase steels are currently produced in addition to cold rolled DP and RA steels. New continuously annealed grades with tensile strength levels of up to 1000 MPa in combination with sufficient ductility for applications mainly in the field of structural automobile elements make use of the classic advantages of microalloying as well as the principles of DP and TRIP steels. Further improvement of properties will be reached by the new class of high manganese alloyed steels. 相似文献
93.
Deferred Splatting 总被引:2,自引:0,他引:2
94.
The coefficients of friction, the friction surface roughening and the mechanisms of wear for 11 metallic materials (high alloy steels and commercially available wear-resistant iron-, nickel- and cobalt-base alloys) were determined by friction tests performed in water at 20 and 300°C. The material combination 1.4550/1.4550 showed adhesive wear and coefficients of friction f of up to 1.6 at low surface pressures. Pure abrasive wear was found with seven hard alloy combinations. Typical curves of the coefficient of friction as a function of the number of friction cycles were obtained with both adhesive and abrasive wear. Short-term tests allowed the tendency of a material combination to adhesive wear to be determined. It was also found that the form of the curve of the coefficient of friction as a function of the number of friction cycles indicated which wear mechanism was operating. 相似文献
95.
De Oliveira PR Calligaris IB Roma GC Bechara GH Mathias MI 《Microscopy research and technique》2012,75(6):727-736
This study presents the morpho-histological and histochemical characterization of the testes, integument, Malpighian tubules, and midgut of engorged Rhipicephalus sanguineus nymphs on the detachment day, showing the morphological and physiological characteristics to this phase in the life cycle of these individuals. The testis is constituted by germinative cells (only spermatogonia) with large, round-shaped and strongly stained nuclei which are organized into cysts by a thin layer of somatic cells. The integument consists of a cuticle subdivided into epicuticle (lipoprotein) and procuticle (glycoproteic), and a layer of epithelial cells which present glycolipoprotein elements. The procuticle presents two distinct regions: the exocuticle (next to the epicuticle) and the endocuticle (next to the epithelial layer). The Malpighian tubules present a simple epithelium with small flat and/or cubic cells, which form its wall and delimitates a lumen full of lipoprotein material. The midgut consists of an epithelial wall formed by two types of digestive cells, spent cells and empty digest cells, and by generative cells supported by a basal lamina and a thin layer of muscular tissue. This study described the main organs of engorged nymphs of R. sanguineus, to generate information that can help researchers to better understand the biology of these ectoparasites; which is fundamental for the development of compounds that are less aggressive to the environment. In addition, if the immature stages of the ticks are controlled, the number of adult ticks able to cause damages to the animals--and to the man as well--is also under control. 相似文献
96.
Mathias Bürger Giuseppe Notarstefano Francesco Bullo Frank Allgöwer 《Automatica》2012,48(9):2298-2304
In this paper we propose a novel distributed algorithm to solve degenerate linear programs on asynchronous peer-to-peer networks with distributed information structures. We propose a distributed version of the well-known simplex algorithm for general degenerate linear programs. A network of agents, running our algorithm, will agree on a common optimal solution, even if the optimal solution is not unique, or will determine infeasibility or unboundedness of the problem. We establish how the multi-agent assignment problem can be efficiently solved by means of our distributed simplex algorithm. We provide simulations supporting the conjecture that the completion time scales linearly with the diameter of the communication graph. 相似文献
97.
Randy Przybylla Christina Susanne Mullins Mathias Krohn Stefan Oswald Michael Linnebacher 《International journal of molecular sciences》2022,23(17)
Commonly used intestinal in vitro models are limited in their potential to predict oral drug absorption. They either lack the capability to form a tight cellular monolayer mimicking the intestinal epithelial barrier or the expression of cytochrome P450 3A4 (CYP3A4). The aim of this study was to establish a platform of colorectal cancer patient-derived cell lines for evaluation of human intestinal drug absorption and metabolism. We characterized ten 2D cell lines out of our collection with confluent outgrowth and long-lasting barrier forming potential as well as suitability for high throughput applications with special emphasis on expression and inducibility of CYP3A4. By assessment of the transepithelial electrical resistance (TEER) the cells barrier function capacity can be quantified. Very high TEER levels were detected for HROC60. A high basal CYP3A4 expression and function was found for HROC32. Eight cell lines showed higher CYP3A4 induction by stimulation via the vitamin D receptor compared to Caco-2 cells (5.1- to 16.8-fold change). Stimulation of the pregnane X receptor led to higher CYP3A4 induction in two cell lines. In sum, we identified the two cell lines HROC183 T0 M2 and HROC217 T1 M2 as useful tools for in vitro drug absorption studies. Due to their high TEER values and inducibility by drug receptor ligands, they may be superior to Caco-2 cells to analyze oral drug absorption and intestinal drug–drug interactions. Significance statement: Selecting appropriate candidates is important in preclinical drug development. Therefore, cell models to predict absorption from the human intestine are of the utmost importance. This study revealed that the human cell lines HROC183 T0 M2 and HROC217 T1 M2 may be better suited models and possess higher predictive power of pregnane X receptor- and vitamin D-mediated drug metabolism than Caco-2 cells. Consequently, they represent useful tools for predicting intestinal absorption and simultaneously enable assessment of membrane permeability and first-pass metabolism. 相似文献
98.
Marek Skrzypski Pawe A. Koodziejski Ewa Pruszyska-Oszmaek Tatiana Wojciechowicz Paulina Janicka Magorzata Krek Emilian Maek Mathias Z. Strowski Krzysztof W. Nowak 《International journal of molecular sciences》2022,23(17)
Adropin is a peptide hormone encoded by Energy Homeostasis Associated gene. Adropin modulates energy homeostasis and metabolism of lipids and carbohydrates. There is growing evidence demonstrating that adropin enhances insulin sensitivity and lowers hyperlipidemia in obese mice. The aim of this study was to investigate the effects of daily administration of adropin for four weeks in mice with experimentally induced type 2 diabetes (T2D). Adropin improved glucose control without modulating insulin sensitivity. Adropin reduced body weight, size of adipocytes, blood levels of triacylglycerol and cholesterol in T2D mice. T2D mice treated with adropin had lower liver mass, reduced hepatic content of triacylglycerol and cholesterol. Furthermore, adropin attenuated elevated blood levels of hepatic enzymes (ALT, AST, GGT and ALP) in T2D mice. In T2D mice, adropin increased the circulating adiponectin level. Adropin had no effects on circulating insulin and glucagon levels and did not alter pancreatic islets morphology. These results suggest that adropin improves glucose control, lipid metabolism and liver functions in T2D. In conjunction with reduced lipid content in hepatocytes, these results render adropin as an interesting candidate in therapy of T2D. 相似文献
99.
Jan Traub Katja Grondey Tobias Gassenmaier Dominik Schmitt Georg Fette Stefan Frantz Valrie Boivin-Jahns Roland Jahns Stefan Strk Guido Stoll Theresa Reiter Ulrich Hofmann Martin S. Weber Anna Frey 《International journal of molecular sciences》2022,23(18)
Acute ischemic cardiac injury predisposes one to cognitive impairment, dementia, and depression. Pathophysiologically, recent positron emission tomography data suggest astroglial activation after experimental myocardial infarction (MI). We analyzed peripheral surrogate markers of glial (and neuronal) damage serially within 12 months after the first ST-elevation MI (STEMI). Serum levels of glial fibrillary acidic protein (GFAP) and neurofilament light chain (NfL) were quantified using ultra-sensitive molecular immunoassays. Sufficient biomaterial was available from 45 STEMI patients (aged 28 to 78 years, median 56 years, 11% female). The median (quartiles) of GFAP was 63.8 (47.0, 89.9) pg/mL and of NfL 10.6 (7.2, 14.8) pg/mL at study entry 0–4 days after STEMI. GFAP after STEMI increased in the first 3 months, with a median change of +7.8 (0.4, 19.4) pg/mL (p = 0.007). It remained elevated without further relevant increases after 6 months (+11.7 (0.6, 23.5) pg/mL; p = 0.015), and 12 months (+10.3 (1.5, 22.7) pg/mL; p = 0.010) compared to the baseline. Larger relative infarction size was associated with a higher increase in GFAP (ρ = 0.41; p = 0.009). In contrast, NfL remained unaltered in the course of one year. Our findings support the idea of central nervous system involvement after MI, with GFAP as a potential peripheral biomarker of chronic glial damage as one pathophysiologic pathway. 相似文献
100.
Hannes Holm Markus Buschle Robert Lagerström Mathias Ekstedt 《Software and Systems Modeling》2014,13(2):825-841
Enterprise Architecture (EA) is an approach used to provide decision support based on organization-wide models. The creation of such models is, however, cumbersome as multiple aspects of an organization need to be considered, making manual efforts time-consuming, and error prone. Thus, the EA approach would be significantly more promising if the data used when creating the models could be collected automatically—a topic not yet properly addressed by either academia or industry. This paper proposes network scanning for automatic data collection and uses an existing software tool for generating EA models (ArchiMate is employed as an example) based on the IT infrastructure of enterprises. While some manual effort is required to make the models fully useful to many practical scenarios (e.g., to detail the actual services provided by IT components), empirical results show that the methodology is accurate and (in its default state) require little effort to carry out. 相似文献