Centrifugal ironmaking.

A process for producing liquid iron from iron ore is being developed on the pilot plant scale that avoids the use of high grade metallurgical coal and the agglomeration of iron ore concentrates. The use of a centrifuge furnace provides the maximum surface area for reaction between layers of molten iron oxide and solid carbon. The iron product is centrifuged to the walls of the reactor where it provides a protective barrier between the highly corrosive liquid slag and the refractory walls. Carbon monoxide, released from the reduction reaction, combusts with oxygen in the central gas core and the heat produced is radiated back to the reacting species.To help understand the interaction of the various physical and chemical reactions occurring inside the reactor, a mathematical model had been written describing the process. Laboratory scale studies were carried out to examine and test the validity of some of the assumptions used in the model, and where necessary modify these assumptions. Two such investigations were the reaction between solid carbon and liquid iron bearing slags at temperatures up to 2 135 K, and the determination of heat and mass transfer coefficients from the central gas core to the rotating bed using a naphthalene sublimation technique.To widen the basis on which the predictions from the model could be compared with actual pilot plant operating data, a series of experiments were carried out on the plant covering a broad range of input conditions. These experiments were carried out in the batch mode i.e. the raw materials were charged into the furnace until its capacity was reached, after which the entire contents were discharged, analysed, and compared with the predictions from the mathematical model. A systematic empiricalcampaign was then carried out to determine more realistic values for the parameters used in the model. Sufficient information was obtained from this study to provide the optimum conditions for attempting continuous ironmaking operations on the pilot plant.Three continuous ironmaking experiments were carried out, with the maximum length of continuous operation in any one experiment being of ten hours duration. Improvements in operation and measurement techniques enabled process data to be collected at regular intervals which allowed the process efficiency to be determined on a continuous basis.The iron ore input rate was held constant at kg/h and high conversionefficiencies of iron from iron ore of up to 80% were obtained

Simultaneous X-ray and IR variability in the quasar 3C 273

The definitive version is available at www.blackwell-synergy.com. Copyright Blackwell Publishing DOI : 10.1046/j.1365-8711.1999.02959.xFrom a combination of high quality X-ray observations from the NASA Rossi X-ray Timing Explorer (RXTE), and infrared observations from the UK Infrared Telescope (UKIRT) we show that the medium energy X-ray (3-20 keV) and near infrared fluxes in the quasar 3C273 are highly correlated. It is widely believed that the X-ray emission in quasars like 3C273 arises from Compton scattering of low energy seed photons and our observations provide the first reliable detection of correlated variations in 3C273 between the X-ray band and any lower energy band. For a realistic electron distribution we demonstrate that it is probable that each decade of the seed photon distribution from the mm to IR waveband contributes roughly equally to the medium energy X-ray flux. However the expected mm variations are too small to be detected above the noise, probably explaining the lack of success of previous searches for a correlation between X-ray and mm variations. In addition we show that the infrared leads the X-rays by 0.75±0.25 days. These observations rule out the ‘External Compton’ emission process for the production of the X-rays.Peer reviewe

Validation of a rapid, automated method for the measurement of ethylene glycol in human plasma.

BACKGROUND Ethylene glycol is a highly toxic compound found in various household products. Cases of poisoning are rare but may be fatal unless diagnosed and treated promptly. Early recognition of poisoning is critical for the management and recovery of patients. Indirect testing is not specific for the presence of ethylene glycol. Therefore, urgent and accurate measurement should be sought if ingestion is suspected in order to determine the need for treatment with an antidote. Here, we present the validation of an automated assay for measurement of ethylene glycol on an Abbott Architect using a commercially available kit (Catachem). METHODS Analytical parameters of imprecision, linearity, stability and bias were determined using spiked human plasma samples processed on both the Catachem assay and on an in-house gas chromatography-mass spectrometry method. Interference was assessed using samples collected into a variety of sample collection tubes and spiked with a number of alcohols. RESULTS Excellent agreement was observed between the two methodologies with the enzymatic assay demonstrating linearity and precision across the relevant clinical range (50-3000 mg/L). In addition, the Catachem assay displayed no interference from a number of different sample tubes and alcohols. However, propylene glycol interference was observed at concentrations associated with excessive use (>1 g/L) and 2,3-butanediol interference observed at concentrations associated with butanone ingestion. Inspection of the enzymatic reaction profile was found to differentiate between alcohols. CONCLUSIONS This automated assay is suitable for the diagnosis of ethylene glycol poisoning and is now in routine use, enabling the laboratory to provide a rapid 24 h service with support by gas chromatography-mass spectrometry as necessary

Recent progress in L-H transition studies at JET: Tritium, Helium, Hydrogen and Deuterium

We present an overview of results from a series of L-II transition experiments undertaken at JET since the installation of the ITER-like-wall (JET-ILW), with beryllium wall tiles and a tungsten divertor. Tritium, helium and deuterium plasmas have been investigated. Initial results in tritium show ohmic L-H transitions at low density and the power threshold for the L-H transition (P-LH) is lower in tritium plasmas than in deuterium ones at low densities, while we still lack contrasted data to provide a scaling at high densities. In helium plasmas there is a notable shift of the density at which the power threshold is minimum ((n) over bar (e,min)) to higher values relative to deuterium and hydrogen references. Above (n) over bar (e,min) (He) the L-H power threshold at high densities is similar for D and He plasmas. Transport modelling in slab geometry shows that in helium neoclassical transport competes with interchange-driven transport, unlike in hydrogen isotopes. Measurements of the radial electric field in deuterium plasmas show that E-r shear is not a good indicator of proximity to the L-H transition. Transport analysis of ion heat flux in deuterium plasmas show a non-linearity as density is decreased below (n) over bar (e,min). Lastly, a regression of the JET-ILW deuterium data is compared to the 2008 ITPA scaling law

Intravenous NPA for the treatment of infarcting myocardium early: InTIME-II, a double-blind comparison on of single-bolus lanoteplase vs accelerated alteplase for the treatment of patients with acute myocardial infarction

Aims to compare the efficacy and safety of lanoteplase, a single-bolus thrombolytic drug derived from alteplase tissue plasminogen activator, with the established accelerated alteplase regimen in patients presenting within 6 h of onset of ST elevation acute myocardial infarction. Methods and Results 15 078 patients were recruited from 855 hospitals worldwide and randomized in a 2:1 ratio to receive either lanoteplase 120 KU. kg-1 as a single intravenous bolus, or up to 100 mg accelerated alteplase given over 90 min. The primary end-point was all-cause mortality at 30 days and the hypothesis was that the two treatments would be equivalent. By 30 days, 6.61% of alteplase-treated patients and 6.75% lanoteplase-treated patients had died (relative risk 1.02). Total stroke occurred in 1.53% alteplase- and 1.87% lanoteplase-treated patients (ns); haemorrhagic stroke rates were 0.64% alteplase and 1.12% lanoteplase (P=0.004). The net clinical deficit of 30-day death or non-fatal disabling stroke was 7.0% and 7.2%, respectively. By 6 months, 8.8% of alteplase-treated patients and 8.7% of lanoteplase-treated patients had died. Conclusion Single-bolus weight-adjusted lanoteplase is an effective thrombolytic agent, equivalent to alteplase in terms of its impact on survival and with a comparable risk-benefit profile. The single-bolus regimen should shorten symptoms to treatment times and be especially convenient for emergency department or out-of-hospital administration. (C) 2000 The European Society of Cardiology