Manufacturing method for monolithic dye-sensitised solar cells permitting long-term stable low-power modules

A manufacturing technique for monolithic dye-sensitised solar cells is presented. Encapsulated modules designed for indoor low-power applications have been prepared using industrial methods and equipment. Under certain conditions (light intensity <5000 lx, temperature between –10°C and 50°C, and relative humidity of appr. 50%), the modules have performed well and shown excellent long-term stability. Moreover, modules withstand illumination in combination with storage at 100% relative humidity. However, a certain degradation of the module performance takes place at illuminations exceeding 5000 lx and temperatures exceeding 50°C.     

Lack of de-epoxidation of type B trichothecenes in incubates with human faeces

The ability of human gastrointestinal organisms to transform the trichothecenes 3-acetyldeoxynivalenol and nivalenol was investigated. Samples of human faeces were incubated under anaerobic conditions for 48 h with the toxins. They were then extracted and analysed for trichothecenes and metabolites. 3-Acetyldeoxynivalenol was metabolized to deoxynivalenol during the incubation period. In contrast to what has been reported for other species such as rats, mice and pigs, no de-epoxidated metabolites were detected in the faecal incubates. The toxicological significance of the difference in the intestinal ability to transform trichothecenes between species is unknown.     

Neural Networks Analysis of Steel Plate Processing Augmented by Multi‐objective Genetic Algorithms

An earlier neural network analysis of processing of steel plates through hot rolling was subjected to a further refined analysis through some flexible neural networks that evolved using a multi‐objective predator‐prey genetic algorithm. The original data set expressing the Yield Strength and Ultimate Tensile Strength of the rolled slabs in terms of a total of 108 process variables were subjected to a systematic pruning through this evolutionary approach, till the nitrogen content of the steel emerged as the most significant input variable. A theoretical explanation is provided for this slightly unexpected result.     

Human urine - Chemical composition and fertilizer use efficiency

Stored human urine had pH values of 8.9 and was composed of eight main ionic species (> 0.1 meq L^–1), the cations Na, K, NH₄, Ca and the anions, Cl, SO₄, PO₄ and HCO₃. Nitrogen was mainly (> 90%) present as ammoniacal N, with ammonium bicarbonate being the dominant compound. Urea and urate decomposed during storage. Heavy metal concentrations in urine samples were low compared with other organic fertilizers, but copper, mercury, nickel and zinc were 10–500 times higher in urine than in precipitation and surface waters. In a pot experiment with¹⁵N labelled human urine, higher gaseous losses and lower crop uptake (barley) of urine N than of labelled ammonium nitrate were found. Phosphorus present in urine was utilized at a higher rate than soluble phosphate, showing that urine P is at least as available to crops as soluble P fertilizers.     

Analyses of coronary graft patency after aprotinin use: results from the International Multicenter Aprotinin Graft Patency Experience (IMAGE) trial

OBJECTIVE: We examined the effects of aprotinin on graft patency, prevalence of myocardial infarction, and blood loss in patients undergoing primary coronary surgery with cardiopulmonary bypass. METHODS: Patients from 13 international sites were randomized to receive intraoperative aprotinin (n = 436) or placebo (n = 434). Graft angiography was obtained a mean of 10.8 days after the operation. Electrocardiograms, cardiac enzymes, and blood loss and replacement were evaluated. RESULTS: In 796 assessable patients, aprotinin reduced thoracic drainage volume by 43% (P < .0001) and requirement for red blood cell administration by 49% (P < .0001). Among 703 patients with assessable saphenous vein grafts, occlusions occurred in 15.4% of aprotinin-treated patients and 10.9% of patients receiving placebo (P = .03). After we had adjusted for risk factors associated with vein graft occlusion, the aprotinin versus placebo risk ratio decreased from 1.7 to 1.05 (90% confidence interval, 0.6 to 1.8). These factors included female gender, lack of prior aspirin therapy, small and poor distal vessel quality, and possibly use of aprotinin-treated blood as excised vein perfusate. At United States sites, patients had characteristics more favorable for graft patency, and occlusions occurred in 9.4% of the aprotinin group and 9.5% of the placebo group (P = .72). At Danish and Israeli sites, where patients had more adverse characteristics, occlusions occurred in 23.0% of aprotinin- and 12.4% of placebo-treated patients (P = .01). Aprotinin did not affect the occurrence of myocardial infarction (aprotinin: 2.9%; placebo: 3.8%) or mortality (aprotinin: 1.4%; placebo: 1.6%). CONCLUSIONS: In this study, the probability of early vein graft occlusion was increased by aprotinin, but this outcome was promoted by multiple risk factors for graft occlusion.     

The Yield Stress of Gas/Liquid/Fibre Suspensions

Yield stress measurements of gas/liquid/fibre suspensions, were conducted to examine the effect of gas concentration as well as fibre concentration. Obtaining a well mixed stable pulp suspension with gas was difficult. A transparent model system consisting of glass fibres submersed in refractive index matched liquid gave stable suspensions and had the additional advantage of allowing visual observations. The measurements were performed in a baffled shear tester and concentrations were in the range of 0–12.5% vol. gas and 8–14% wt. fibres. Results show that yield stress decreases with increasing gas fraction for constant fibre concentrations. Since the fibre concentration is defined in the liquid phase, the amount of fibres decreases with increasing gas concentration. This fact alone partly explains the decrease in yield stress, but the gas also has a direct impact on the decrease in yield stress. Further, as expected, the yield stress increases with increasing fibre concentrations when the gas fraction is kept constant.     

LDA Measurements on a Turbulent Gas/Liquid/Fibre Suspension

Detailed continuous phase flow measurements (mean and RMS velocities) by Laser Doppler Anemometry (LDA) of a turbulent gas/fibre/liquid suspension in a rotary shear tester have been performed with simultaneous torque measurements. The model system comprises a refractive‐index matched suspension in the 4‐12% wt. range with gas contents up to 15% vol. The two transition points, found by Andersson and Rasmuson (2000), were detected also with gas present and appear at higher impeller speeds with increasing gas and fibre concentrations. Plotting RMS and mean velocities versus impeller speed and power input, it is found that both decrease with increasing gas and fibre contents.     

Determination of the molecular weight distribution of cellulose on calibrated gel columns

CMC samples obtained by gel filtration on a preparative scale were used to calibrate an agarose column. The relation between molecular weight and the peak elution volume for monodisperse samples were calculated as well as the relation between band broadening and the peak elution volume. In the calculations of the molecular weight distribution curves of the studied CMC samples, consideration was given to the variable band broadening by proper transformations of the experimental data, thus making it possible to obtain numerical solutions free from oscillations. The method admits a rapid determination of the molecular weight distribution of cellulose and related materials.