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1.
Conclusion  Electric steelmaking is assuming an increasingly larger role in steel production, with the use of larger quantities of scrap substitutes and scrap of different levels of quality. Thus, the goal is to improve the economic and technical indices of the furnaces, despite the difficulties and limitations connected with the use of this new type of charge. In improving charging and melting operations and furnace equipment, certain basic requirements must be met:
–  - maximum use must be made of the available energy (electrical and internal) during the heat;
–  - the use of electric power and carbon in the furnace must be optimized;
–  - the time the are is off due to cold-charging must be made as short as possible;
–  - the steelmaking process must be made safe and environmentally clean.
These requirements can best be met in a continuously operating furnace. The research and development projects being carried out at the Paul Wert Company are oriented in this very direction. The first step has been taken—a method has been developed for the continuous introduction of charge materials into the furnace. The next step is continuous melting and continuous refining of carbon, sulfur, and phosphorus from the melt, and it will involve the development of a furnace in which slag will be removed from the furnace and granulated continuously and metal will be tapped from the furnace periodically. Paul Wert Company (Luxembourg). Translated from Metallurg, No. 3, pp. 41–44, March, 1999.  相似文献   
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We report a patient aged 41 years with fever of unknown origin. Notable aspects of his travel history were a trip to the Philippines and a sailing trip around Sicily. The patient presented with fever up to 40 degrees C since 4 weeks, weakness, headache, hepatosplenomegaly and night sweat. No specific cause could be found. Based on clinical findings tuberculosis was suspected and empirical tuberculostatic treatment was started. However, during the following 6 weeks the patient's condition deteriorated. A bone marrow biopsy performed to exclude a haematological malignancy revealed Leishmania sp. in macrophages. This histological diagnosis was confirmed retrospectively by re-examination of a previously performed liver biopsy and by an increased anti-leishmania serum antibody titer of 1:1280. The patient was treated with sodium stibogluconate (pentostam, 850 mg) for 30 days and recovered slowly.  相似文献   
4.
Corrosion behaviour of hot dip galvanized steel in cold and warm model waters with gassing by CO2 and/or O2 and as a function of lime hardness In oxygen-or carbon dioxide free waters the corrosion is due to the evolution of hydrogen from water; this corrosion is accelerated by higher chloride contents. It is therefore advisable to keep chloride contents below 150 mg/l Cl?. In the presence of oxygen the zinc coating is attacked by oxygen; here, too, the influence of chlorides is quite evident. The presence of a certain water hardness gives rise to the formation of protective layers. When the water contains carbon dioxide the corrosion is of the acid type; it is inhibited, however, by protective layer formation. It should be borne in mind, that the hardness of water has a favourable effect only in cold waters, while it is very deleterious in warm waters. Water flow gives rise to accelerated corrosion. Pitting can be prevented by oxygen elimination or by the formation of protective layers. This layer formation is optimum under lime-carbonic acid equilibrium conditions.  相似文献   
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Quantitative ultrastructural myocardial changes of myocardium of the japanese quail (Coturnix coturnix japonica) were studied during an immobilization stress (hypodynamia) lasting 9, 30, 60 and 90 days. Hypodynamic quails were fixed by waistcoats to the feeding place simulating conditions of long lasting space flight which the quails were determined for. The surveyed morphological parametres were: mitochondrial rate, mitochondrial volume in % of cytoplasm, volume of myofibres in % of cytoplasm, volume of single mitochondria, extent of cristolysis. Progressive mitochondrial hydratation and even local oedema were observed during the experiment. It led to a progressive increase of mitochondrial volume and simultaneous decrease of volume of myofilaments as a sign of intracellular atrophy of myofibres. The results correlated well with a decreased mass of myofibres observed in experimental quails from space flight on the orbital station MIR.  相似文献   
6.
This paper reports on the hydrodynamic droplet instabilities of different sizes and viscosities due to shear forces in a rectangular channel. Water‐glycerine droplets of different volumes are investigated. A new and nonambiguous definition for the critical velocity of droplet detachment and a new mathematical correlation between the critical velocity vcrit and the fluid properties are presented. The measurements show that vcrit decreases with the droplet volume but at the same time the contour deformation increases. With increasing viscosity of the liquid droplet, i.e., higher glycerine mass fraction, the contour deformation becomes more prominent and an increase in vcrit can be observed. With respect to the fluid properties and droplet volumes, three different motion patterns are detected.  相似文献   
7.
There is a lack of knowledge regarding the connection between the ocular and nasal epithelia. This narrative review focuses on conjunctival, corneal, ultrastructural corneal stroma, and nasal epithelia as well as an introduction into their interconnections. We describe in detail the morphology and physiology of the ocular surface, the nasolacrimal ducts, and the nasal cavity. This knowledge provides a basis for functional studies and the development of relevant cell culture models that can be used to investigate the pathogenesis of diseases related to these complex structures. Moreover, we also provide a state-of-the-art overview regarding the development of 3D culture models, which allow for addressing research questions in models resembling the in vivo situation. In particular, we give an overview of the current developments of corneal 3D and organoid models, as well as 3D cell culture models of epithelia with goblet cells (conjunctiva and nasal cavity). The benefits and shortcomings of these cell culture models are discussed. As examples for pathogens related to ocular and nasal epithelia, we discuss infections caused by adenovirus and measles virus. In addition to pathogens, also external triggers such as allergens can cause rhinoconjunctivitis. These diseases exemplify the interconnections between the ocular surface and nasal epithelia in a molecular and clinical context. With a final translational section on optical coherence tomography (OCT), we provide an overview about the applicability of this technique in basic research and clinical ophthalmology. The techniques presented herein will be instrumental in further elucidating the functional interrelations and crosstalk between ocular and nasal epithelia.  相似文献   
8.
The microstructures of 316L stainless steel created by rapid solidification are investigated by comparing the similar microstructures of individual hatches of directed energy deposition additive manufacturing(DED-AM) and those of single, laser surface-melted tracks formed on a solid plate. High recoil pressure,which is exponentially dependent on the laser beam power density, induces convection of the melt pool,which causes formation of microstructural bands in the as-solidified microstructure. The microstructural bands are associated with changes in the chromium concentration and are a significant component of the inhomogeneous microstructure of DED-AM.  相似文献   
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The nuclear farnesoid X receptor (FXR) and the enzyme soluble epoxide hydrolase (sEH) are validated molecular targets to treat metabolic disorders such as non-alcoholic steatohepatitis (NASH). Their simultaneous modulation in vivo has demonstrated a triad of anti-NASH effects and thus may generate synergistic efficacy. Here we report dual FXR activators/sEH inhibitors derived from the anti-asthma drug Zafirlukast. Systematic structural optimization of the scaffold has produced favorable dual potency on FXR and sEH while depleting the original cysteinyl leukotriene receptor antagonism of the lead drug. The resulting polypharmacological activity profile holds promise in the treatment of liver-related metabolic diseases.  相似文献   
10.
OBJECTIVE: To further investigate the role that cytogenetic may play in the diagnosis and prognosis of leukemia, a study was conducted in 319 acute leukemias. METHODS: 100 patients with acute lymphoblastic leukemia (ALL) and 219 patients with acute non-lymphoblastic leukemia (ANLL) were from Rui Jin Hospital, Xin Hua Hospital, Ren Ji Hospital and Shanghai Children's Hospital. Their cytogenetic data were analyzed together with those of morphology, immunology and clinical prognosis. RESULTS: In ALL group, 48 cases were karyotypically normal whereas 52 cases revealed chromosomal changes, among which 32 had quantitative abnormalities and 20 had qualitative abnormalities. The translocation t(9; 22) was identified in 11 out of 20 cases of structural aberrations (55%). Specific structural aberrations t(9; 22) and t(8; 14) were detected to be related to B-lineage associated differentiation antigens and t(8; 14) also with ALL-L3 according to FAB classification. With regard to clinical prognosis, the survival rate of structural aberration subset decreased significantly compared with the normal karyotype subset (P < 0.05). However, no statistically significant difference was found between hyperdiploidy subset (not including near-triploidy) and normal karyotype subset (P > 0.75). In ANLL group, 80% of de novo patients and relapsed patients had chromosomal abnormalities. Importantly, structural aberrations accounted for 73% of these abnormalities and frequently corresponded to specific types of FAB classification. Relevant prognostic studies demonstrated that t(15; 17) subset had the best overall survival probability, followed by t(8; 21) and normal karyotype subset, while the numerical aberration subset showed a relatively poor prognosis. CONCLUSION: Our data confirmed that cytogenetic study is important for the molecular study of the leukemogenesis. On the other hand, it also provides an independent parameter for prognosis in acute leukemia.  相似文献   
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