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Off-design performance investigation of a low calorific value gas fired generic-type single-shaft gas turbine

When low calorific value gases are fired, the performance and stability of gas turbines may deteriorate due to a large amount of inertballast and changes in working fluid properties. Since it is rather rare to have custom-built gas turbines for low lower heating value (LHV) operation, the engine will be forced to operate outside its design envelope. This, in turn, poses limitations to usable fuel

Size dependent fragmentation of argon clusters in the soft x-ray ionization regime.

Photofragmentation of argon clusters of average size ranging from 10 up to 1000 atoms is studied using soft x-ray radiation below the 2p threshold and multicoincidence mass spectroscopy technique. For small clusters (N=10), ionization induces fast fragmentation with neutral emission imparting a large amount of energy. While the primary dissociation takes place on a picosecond time scale, the fragm

Detection of short lived radioisotopes as a fast diagnostic for intense laser-solid interactions

As a diagnostic of high-intensity laser interactions (> 10(19) W cm(-2)), the detection of radioactive isotopes is regularly used for the characterization of proton, neutron, ion, and photon beams. This involves sample removal from the interaction chamber and time consuming post shot analysis using NaI coincidence counting or Ge detectors. This letter describes the use of in situ detectors to meas

Combustion process in a biomass grate fired industry furnace: a CFD study

This paper presents a CFD investigation of the combustion process in a 50 MW grate fired furnace. The CFD results were compared with available experimental data at the furnace Outlet to validate the models for the volatile oxidation and NOx formation. The models were then used to predict the effect of a 'ECO' tube system on NOx emissions. It was shown that with an improved flow structure and air d

Mitotic instability in cancer - Is there method in the madness?

It has been known for more than a century that neoplastic cells often exhibit disturbances of the mitotic process, but the causes have only recently been thoroughly explored. In many cancers, a combination of cell cycle checkpoint deficiency and abnormal shortening of telomeres predisposes to unbalanced chromosome segregation at cell division and the development of complex genomic rearrangements.

Neuronal death in nigral grafts in the absence of poly (ADP-ribose) polymerase activation

The exact causes of the extensive cell death in nigral transplants are still unknown. Since poly-(ADP-ribose) polymerase (PARP) overactivation has been implicated in neuronal death, we examined the effects of PARP on the survival of nigral grafts by using donor tissue from PARP knock-out or wild-type mice. Eight hours after preparation of the nigral cell suspension, cell damage was quantified by m

Self-diffusion of nonfreezing water in porous carbohydrate polymer systems studied with nuclear magnetic resonance

Water is an integral part of the structure in biological porous materials such as wood and starch. A problem often encountered in the preparation of samples for, e.g., electron microscopy is that removal of water leads to a decreasing distance between supermolecular structural elements and a distortion of the structure. It is, therefore, of interest to find methods to investigate these materials i

Jump Spillover in International Equity Markets

In this article we study jump spillover effects between a number of country equity indexes. In order to identify the latent historical jumps of each index, we use a Bayesian approach to estimate a jump-diffusion model on each index. We look at the simultaneous jump intensities of pairs of countries and the probabilities that jumps in large countries cause jumps or unusually large returns in other

Sample preparation effects on the compaction properties of Swedish fine-grained tills

Fine-grained tills are a dominant feature of the drift geology of Sweden. Until recently their use in earthworks applications has been limited due to the plentiful supply of naturally occurring gravel and crushed rock, and their high sensitivity to moisture content change which often leads to the view that fine-grained tills are problem soils. Environmental and economic factors are, however, leadi

An atypical intra-platform environment and biota from the Silurian of Gotland, Sweden

A condensed shale from the middle Silurian of Gotland (Sweden) is herein described with regard to its biotic and environmental significance. The fauna is characterised by an overall low diversity and anomalous abundance patterns, notably a mass-occurrence of scolecodonts. Other elements include abundant chitinozoans, dendroid and graptoloid graptolites, conodonts, eurypterids, and the brachiopod L

Binding of adenosine to pendant phenylboronate groups of thermoresponsive copolymer: a quantitative study

Binding of adenosine to the thermosensitive copolymer of N-isopropylacrylamide and 3-(acrylamido)aminophenylboronic acid (82:18, m ($) over bar (n)=47000 g center dot mol(-1)) was studied by equilibrium dialysis at 22 degrees C and 37 degrees C, in a 0.1 m glycine buffer containing 0.1 m NaCl at pH 9.2. The copolymer exhibited a the phase transition temperature (T-p) of 26.5 degrees C under the ab

Sample preparation using a miniatuarized supported liquid membrane device connected on-line to packed capillary liquid chromatography

A miniaturized supported liquid membrane device has been developed for sample preparation and connected on-line to a packed capillary liquid chromatograph. The device consists of hydrophobic polypropylene hollow fiber, inserted and fastened in a cylindrical channel in a Kel-F piece. The pores of the fiber are filled with an organic solvent, in this study 6-undecanone, thus forming a liquid membran

Plasminogen activators and plasminogen activator inhibitors in synovial fluid. Difference between inflammatory joint disorders and osteoarthritis

The plasminogen activator (PA)/plasminogen activator inhibitor (PAI) system is believed to be involved in connective tissue remodelling in joint disease and both PA and PAI production has been shown in several cell types in the joint. We quantified immunoreactive PA and PAI in synovial fluid (SF) and correlated their levels to levels of cartilage derived proteoglycans, radiologically visible joint

Forces Controlling the Rate of DNA Ejection from Page λ

The goal of this work was to investigate how internal and external forces acting on DNA affect the rate of genome ejection from bacteriophage λ after the ejection is triggered in vitro by a λ receptor. The rate of ejection was measured with time-resolved static and dynamic light scattering, while varying such parameters as temperature and packaged DNA length, as well as adding DNA-binding proteins

Transcriptional responses of Paxillus involutus and Betula pendula during formation of ectomycorrhizal root tissue

In order to obtain information on genes specifically expressed in the ectomycorrhizal symbiosis, 3,555 expressed sequence tags (ESTs) were analyzed from a cDNA library constructed from ectomycorrhiza formed between the basidiomycete Paxillus involutus and birch (Betula pendula). cDNA libraries from saprophytically growing fungus (3,964 ESTs) and from axenic plants (2,532 ESTs) were analyzed in par

Haem-delivery proteins in cytochrome c maturation System II

P>Cytochromes of the c-type function on the outer side of the cytoplasmic membrane in bacteria where they also are assembled from apo-cytochrome polypeptide and haem. Two distinctly different systems for cytochrome c maturation are found in bacteria. System I present in Escherichia coli has eight to nine different Ccm proteins. System II is found in Bacillus subtilis and comprises four proteins: C