Über den Stoffübergang zwischen Gasstrom und Erzstück im Hochofen

Berechnung des Partialdruckgefälles in der Gasgrenzschicht eines Erzkornes in einer Hochofenschüttsäule. Erfassung des Einflusses von Korngröße, Reduktionsgrad, Strömungsgeschwindigkeit und Reduktionsgas.     

High prevalence of multiple sclerosis in Switzerland

Prevalence of multiple sclerosis (MS) was determined in the Canton of Berne, Switzerland. This canton is a geographically diverse region at 47 degrees northern latitude with 920,000 inhabitants. Epidemiological data were obtained from the case records of the University Department of Neurology, from the Swiss MS Society, from practising neurologists and from regional hospitals. Diagnostic accuracy was ascertained in retrospect, and only those cases fulfilling the criteria proposed by the Poser Committee were included. Of the patients provided by the Swiss MS Society, only those who had been diagnosed by a neurologist were accepted as definite cases. Changes of population due to migration or death were traced at governmental registry offices, and the place of residence was determined. Using the 1,016 cases of definite and probable MS identified, the minimal prevalence rate was 110 MS cases/100,000 inhabitants in the Canton of Berne on January 1, 1986. The increase in MS in this region since the 1950s was due mainly to the increase in life duration of MS patients rather than an increase in incidence rates over the last 20 years.     

The calcium channel blocker amlodipine raises serum dehydroepiandrosterone sulfate and androstenedione, but lowers serum cortisol, in insulin-resistant obese and hypertensive men

To determine whether the calcium channel blocker amlodipine improves glucose tolerance and alters serum adrenal androgen and glucocorticoid levels in insulin-resistant men, 24 obese and hypertensive men were enrolled into a single blind, placebo-controlled study. An amlodipine group (n = 12) and a placebo group (n = 12) were studied before and after treatment with either amlodipine (5 mg) or placebo capsule twice daily for 7 days by determining serum insulin, glucose, dehydroepiandrosterone sulfate (DHEA-S), androstenedione, and cortisol in the fasting state and during an oral glucose tolerance test. Amlodipine treatment 1) lowered fasting serum insulin (from 273 +/- 19 to 200 +/- 17 pmol/L; P < 0.0005) and glucose (from 5.4 +/- 0.1 to 5.1 +/- 0.1 mmol/L; P < 0.02), 2) reduced the area under the curve for glucose (from 1342 +/- 25 to 1198 +/- 23 mmol/L.min; P = 0.0001) and the area under the curve for insulin (from 155.5 +/- 7.8 to 103.9 +/- 4.3 nmol/L.min; P = 0.0001) during the oral glucose tolerance test, 3) increased fasting serum DHEA-S (from 5.19 +/- 0.37 to 7.95 +/- 0.58 mumol/L; P = 0.0001) and androstenedione (from 5.65 +/- 0.65 to 6.83 +/- 0.53 nmol/L; P < 0.01), and 4) decreased fasting serum cortisol (from 538 +/- 35 to 494 +/- 26 nmol/L; P < 0.05). Fasting serum androstenedione declined slightly in the placebo group (from 5.96 +/- 0.60 to 5.74 +/- 0.57 nmol/L; P < 0.005), but no change occurred in glucose tolerance, fasting serum DHEA-S, or cortisol. We conclude that amlodipine treatment improves glucose tolerance, reduces fasting and glucose-stimulated serum insulin levels, increases serum DHEA-S and androstenedione levels, and decreases circulating cortisol.     

Crossreactivity of workshop monoclonal antibodies with canine blood leukocytes

The human alpha 2HS-glycoprotein is a negative acute phase protein synthesized by hepatocytes. Because of its fragility and the difficulty of its purification, we used recombinant DNA techniques to produce the protein in order to investigate its biological effects. The cDNA coding for the whole alpha 2HS-glycoprotein from human liver library had been cloned into the baculovirus expression vector system using the pVL 1392 transfer vector and Sf9 cells. The recombinant protein was synthesized in the Sf9 cells and was isolated on a hydroxiapatite column from the culture medium. Western blot analysis indicated that the cells synthesized large quantities of the recombinant human protein. The molecular mass of the recombinant AHSG was the same as that of the protein in human plasma but was slightly lower than that of AHSG in the cell culture supernatants of HepG2 and higher than that of AHSG from Hep3B cell cultures, respectively.     

Analysis of the heat transport mechanisms during melting around a horizontal circular cylinder

The melting process around a heated horizontal circular cylinder embedded in a phase change material has been analyzed by means of numerical methods. Both heat conduction and convection have been taken into account to treat this moving boundary problem. Difficulties associated with the complex structure of the timewise changing physical domain (melt region) have been successfully overcome by applying a numerical mapping technique (body-fitted coordinates).Numerical solutions have been obtained for Rayleigh numbers up to Ra = 1.5 · 10⁵, Stefan numbers in the range 0.005 ≦ Ste ≦ 0–08 and for Pr = 50. The results are discussed in detail and indicate that the influence of natural convection has to be considered in all cases.     

Effectiveness measurements for a cooling film disrupted by a row of jets

The influence of cold air jet injection upon filmcooling of combustion chamber walls has been investigated by simulation. The experiments, in which a row of cold air jets is injected perpendicularly to the film cooled test chamber wall, show considerable decreases of the film cooling effectiveness downstream of the jet exit. The same behavior occurs in real combustion chambers of aircraft gas turbine engines. The tests are selected to represent combinations of geometries and flow variables (except the temperature ratios) which are pertinent to gas turbine combustor design. The present investigations cover effectiveness measurements for various combinations of the parameters: a) velocity ratio coolant film to mainstream b) velocity ratio jet to mainstream c) dimensionless distance between coolant film and jet exit d) spacing ratio e) ratio jet diameter to slot height f) ratio lip thickness to slot height.     

Neutron streaming through conical ducts in a water shield

Total albedos, as well as albedos differentiated in terms of both energy and direction, were calculated by means of a Monte Carlo program for cylindrical water surfaces of different radii of curvature. It is shown that a cylindrical coordinate system in which the polar angle is measured relative to the normal on the scattering surface is preferable to one in which this angle is measured relative to the axial direction of the surface. For small polar angles in the preferred system, even when the surface radius approaches the mean free path of the incident neutrons, the effect of this radius remains small. With increasing polar angles the effect of the surface radius becomes more important, especially for those neutrons moving more or less perpendicular to the axial direction of the surface. In the latter case, even at radii as large as 10 n mean free paths, the radial effect at a large polar angles is significant.     

Microwave sensing from satellites

Microwave data from the ESMR sensor of the NIMBUS-6 satellite is used to obtain (i) rainfall rates during a tropical cyclone over the northern part of Western Australia, (ii) wind speed over the surface of the waters of the coastal regions of the southern part of Western Australia, and (iii) the microwave emissivity over the land surface of the southern part of Western Australia.     

Der Wärmeübergang an Hochofeneinsatzstoffen

Ermittlung der Wärmeübergangszahlen an frei umströmten Kugeln und Schüttungen aus Pellets, Sinter, Koks und Erz. Einfluß der Oberflächengestalt, des Wärmeleitvermögens und der Feuchtigkeit der untersuchten Hochofeneinsatzstoffe.