ABSTRACT
The current research proposed a method for optimally combining feed input ratios in order to improve the quantity and quality of daily biogas production through optimizing the variable response level in the Taguchi method. The anaerobic digestion (AD) process of an existing plant in Iran was simulated through a set of two-stage pilot reactors under mesophilic temperature conditions in order to achieve optimal operational performance. Three common substrates (organic fraction of municipal solid wastes, fruit and vegetable wastes, and horse manure) along with two recirculated materials; the post-digestion sludge and the secondary digester slurry, were investigated in 16 experimental runs based on four different pre-surface hypotheses. Comparison of the results of daily biogas energy (J/d/g-VS) in Run#9, to which the actual yield of hydrogen sulfide was minimal in parallel to a methane yield above 100 mL/g-VS, with the result of the optimal run with the ratios provided by the model, showed that the daily biogas energy was improved by 50% comparing to the control Run that had similar conditions to which was being applied in the full-scale existing AD plant.
ABSTRACT
Graphite oxide (GO) and reduced graphene oxide (rGO) nanosheets were synthesized with a low-cost manufacturing method. The morphology and structures of the synthesized samples were studied using X-ray diffraction (XRD), atomic force microscopy (AFM), Fourier-transform infrared (FTIR) and Raman spectroscopy. The efficiencies of GO and rGO as novel candidate adsorbents in the pre-purification of paclitaxel were compared and contrasted with those of commercial graphite (Gt), graphene (G) and multi-wall carbon nanotube (MWCNT). According to UV–vis and HPLC analyses, rGO was evaluated as the best absorbent for the removal of impurities in pre-purification of paclitaxel from plant cell cultures. In contrast, the GO had the poorest proficiency for paclitaxel pre-purification in comparison with the other carbonaceous adsorbents. This is attributed to the existence of many localized defects in the π-structure of GO that is related to weakness ofπ–πstacking interactions between crude extract impurities and GO.
ABSTRACT
BACKGROUND: The differentiation between physiological cardiac enlargement and cardiomyopathy is crucial, considering that most young non-traumatic deaths in sport are due to cardiomyopathy. Currently, there are few data relating to cardiac dimensions in junior elite tennis players. The aim of this study was to define the upper limits of left ventricular dimensions in a large cohort of national adolescent tennis players. METHODS: Between 1996 and 2003, 259 adolescent tennis players (152 males), mean (SD) age 14.8 (1.4) years (range 13-19) and 86 healthy age, gender and body surface matched sedentary controls underwent 12-lead ECG and 2D-transthoracic echocardiography. RESULTS: Inter-ventricular septal end diastolic dimension (IVSd), left ventricular end diastolic dimension (LVEDd) and left ventricular end diastolic posterior wall dimension (LVPWd) in tennis players were significantly higher than in controls (8.9 mm vs 8.3 mm p<0.001, 48.9 mm vs 47.9 mm p<0.05 and 9 mm vs 8.3 mm p<0.001 respectively), however in absolute terms, the difference did not exceed 7%. None of the tennis players had a wall thickness exceeding 12 mm or a left ventricular cavity size exceeding 60 mm. CONCLUSIONS: Tennis players exhibit modest increases in cardiac dimensions, which do not resemble those seen in individuals with cardiomyopathy affecting the left ventricle.
