2,4,6‐Trichlorophenol and phenol removal in methanogenic and partially‐aerated methanogenic conditions in a fluidized bed bioreactor

A fluidized bed bioreactor (FBBR) was operated for more than 575 days to remove 2,4,6‐trichlorophenol (TCP) and phenol (Phe) from a synthetic toxic wastewater containing 80 mg L^?1 of TCP and 20 mg L^?1 of Phe under two regimes: Methanogenic (M) and Partially‐Aerated Methanogenic (PAM). The mesophilic, laboratory‐scale FBBR consisted of a glass column (3 L capacity) loaded with 1 L of 1 mm diameter granular activated carbon colonized by an anaerobic consortium. Sucrose (1 g COD L^?1) was used as co‐substrate in the two conditions. The hydraulic residence time was kept constant at 1 day. Both conditions showed similar TCP and Phe removal (99.9 + %); nevertheless, in the Methanogenic regime, the accumulation of 4‐chlorophenol (4CP) up to 16 mg L^?1 and phenol up to 4 mg L^?1 was observed, whereas in PAM conditions 4CP and other intermediates were not detected. The specific methanogenic activity of biomass decreased from 1.01 ± 0.14 in M conditions to 0.19 ± 0.06 mmolCH₄ h^?1 gTKN^?1 in PAM conditions whereas the specific oxygen uptake rate increased from 0.039 ± 0.008 in M conditions to 0.054 ± 0.012 mmolO₂ h^?1 gTKN^?1, which suggested the co‐existence of both methanogenic archaea and aerobic bacteria in the undefined consortium. The advantage of the PAM condition over the M regime is that it provides for the thorough removal of less‐substituted chlorophenols produced by the reductive dehalogenation of TCP rather than the removal of the parent compound itself. Copyright © 2005 Society of Chemical Industry     

Study of the nozzle flow in a cross-flow turbine

An investigation of the flow inside the nozzle of a Cross-Flow turbine, which is a hydraulic turbine where the rectangular water jet issuing from the nozzle crosses the rotor blades twice, is presented here. Part of the investigation consisted in the experimental measurement of the static pressure distribution on the inside walls of two different nozzle configurations, both with the nozzle mounted alone and in the presence of a rotor. The tests performed in the presence of a rotor included the measurement of efficiency and covered a wide range of working conditions around the best efficiency point. The analysis of the results obtained in this way give us an indication of the influence of the turbine non-dimensional volume flow rate on the flow inside the nozzle and the way it affects the reaction degree of the machine and its efficiency level. Although most of the tests were carried out with a 25-blade rotor, one of the analysed nozzle configurations (that with an inside vane) was also tested with a 10-blade rotor, permitting the assessment of the effect the number of blades has on the flow in the nozzle.The flow inside the nozzle with no inside vane was numerically analysed using a method based on a Schwarz-Christoffel conformal transformation of variables. The numerical results show a fair agreement with the experimental data collected when the rotor was not present. A qualitative discussion of some of the losses occurring in the nozzle is advanced based on the computer results, and its conclusions are used for explaining the poor performance of the nozzle with no inside vane.     

Intestinal obstruction and peritoneal carcinomatosis after endoscopic resection of transitional carcinoma of urinary bladder

Gut involvement in bladder tumours is low, even exceptional in the presence of surface, low-grade neoplasia. The authors explain their experience in the diagnosis and management of a patient treated endoscopically for a vesical surface tumour which subsequently exhibited peritoneal and gut metastatic seeding. The various mechanisms for gut dissemination of vesical neoplasias and the repercussion of their endoscopic management are discussed.     

Thrombotic thrombocytopenic purpura and hemolytic uremic syndrome (TTP/HUS). Description of a series of 35 patients

Subsequent to the implementation of a severity marker stamp in case notes, an audit was performed in 86 admissions with acute asthma to a specialist centre over a 12 month period. Compared to previous audit the documentation of severity markers was significantly better (PEFR: 52% vs 83% p = 0.001, Respiratory rate: 44% vs 81% p = 0.001, ABG: 72% vs 80% p = 0.04, air entry: 58% vs 86% p = 0.001, speech: 27% vs 86% p = 0.001, exhaustion: 4% vs 86% p = 0.001). In contrast to the previous audit where no patient received FiO2 > 0.35, 66% of the cases in the repeat audit received FiO2 0.60 (p = 0.001). The mean duration of admission was five days and showed highest partial correlation (r = 0.6) to the time in hours for the pulse to fall to 80/min. Multiple linear regression showed that this was the only variable best predicting the duration of admission (R2 = 0.3). Admission pulse rate (p = 0.04) and serum K+ (p = 0.04) best discriminated between patients admitted for over and under five days. Logistic regression identified only the admission pulse as significant in calculating the odds of the patient staying in the hospital for > 5 days.     

Bladder pseudotumor in childhood

The application of frozen and radiation sterilized allogenic bone grafts for reconstructions in orthopaedic operations is described. Analysis of results of treatment of 1125 patients was performed. It was found that use of preserved bone allows to reduce the extend and duration of surgery. Nearly total substitution of grafts may be seen in 3 to 8 months after surgery.     

Electric field effects on roto-vibrational transitions of13CD3OH1

We used a Stark-Optoacoustic cell and hybrid waveguide resonators to perform an Infrared and Far Infrared Stark Spectroscopy study on some transitions of¹³CD₃OH. Different behaviours of the transitions in the presence of a d.c. electric field were observed. The Stark splittings of six FIR laser lines ranging from 34 to 136 MHz/kVcm^?1 were determined. The analysis of the behaviour of the IR and FIR transitions in the presence of the external electric fields gives important and exclusive information on the levels involved in the transitions.