Retracted: Hydrogen production using catalytic and noncatalytic supercritical water gasification of bagasse

The above article, published online on 10 May 2014 in Wiley Online Library ( wileyonlinelibrary.com ), has been retracted by agreement between the authors, the journal Editor in Chief, Ibrahim Dincer, and John Wiley & Sons, Ltd. The retraction has been agreed due to overlap between this article and the following article published in Fuel Processing Technology; ‘Hydrogen production via supercritical water gasification of bagasse using unpromoted and zinc promoted Ru/γ‐Al2O3 nanocatalysts’ by Mokhtar Babatabar, Ahmad Tavasoli, Ajay K. Dalai, Umashanker Das. Volume 123, 2014, pages 140–148.     

Experimental assessment of hydrostatic thrust bearing performance

This work presents an experimental study to assess the performance characteristics of hydrostatic thrust bearings. A test rig is designed for testing two configurations of hydrostatic bearings compensated by a capillary tube, one with a mid-circular recess and the other with multi-sectors (four recesses of different recess radii ratios). The performance characteristics have been measured, namely, oil film thickness, recess pressure, pressure distribution and oil flow rate. A specially devised computer program using an iterative technique has been adopted to compute numerically the pressure distribution and predict other performance characteristics. Good agreement has been obtained between predicted theoretical performance and that experimentally measured. The results demonstrate that the bearing recess size and location have a great influence on the performance of the hydrostatic thrust bearing.     

A model for improved solar irradiation measurement at low flux

Accurate measurement of solar radiation heat flux is important in characterizing the performance of CSP plants. Thermopile type Heat Flux Sensors (HFSs) are usually used for this purpose. These sensors are typically reasonably accurate at high heat fluxes. However measurement accuracy drops significantly as the measured radiation is below 1 kW/m², this often leads to underestimation of the actual flux. At the Masdar Institute Beam Down Solar Thermal Concentrator (BDSTC), measurement of fluxes ranging from 0 kW/m² to more than 100 kW/m² is required. To improve the accuracy of the sensors in the lower range around 1 kW/m², we have performed a test under ambient (not-concentrated) sunlight. Such low irradiation levels are experienced in characterizing the concentration quality of individual heliostats. It was found during the test that the measurement at this low range is significantly affected by ambient conditions and transients in the HFS cooling water temperature. A Root Mean Square Error (RMSE) of more than 100 W/m² was observed even though we kept the transients in water temperature to a minimum. Hence we devised a model to account for this measurement error at this flux range. Using the proposed model decreased the RMSE to less than 10 W/m². The application of the model on existing heat flux measurement installations is facilitated by the fact that it only employs easily measurable variables. This model was checked by using a test data set and the results were in good agreement with the training data set.     

Authentication technologies using DNA-based approaches for meats and halal meats determination

Food authenticity and safety are major concerns for researchers, consumers, and particularly the meat industry. Meat products are targets for species substitution and adulteration due to their market value. Presently, the demand for halal products is witnessing a substantial increase. Therefore, it is essential to use appropriate science-based methods for determining the species origin of halal meat. DNA barcoding is a useful technique for the molecular identification of biological specimens, and raw and processed foods. The potential of using DNA barcoding is increasingly applied as an authentication tool for halal animal and meat products. Our review will bring together all DNA-based techniques that have been developed for the authenticity of meat derived from halal and non-halal animals and also their derivatives. Additionally, the present paper will highlight the possibility of using the DNA barcoding approach for halal meat authenticity.     

Ge-doped ZnO nanorods grown on FTO for photoelectrochemical water splitting with exceptional photoconversion efficiency

In this study, a considerable effort has been devoted for the synthesis of Ge-doped ZnO nanorods on FTO as an efficient and robust photoanode material for solar water splitting. A unique, optimized, and ultra-rapid fabrication method to produce uniform nanorods (30–70 nm in diameter) has been demonstrated using radio frequency sputtering followed by electrochemical anodization. The effect of Ge doping on the conductivity, charge carrier concentration, optical, and photoelectrochemical properties of ZnO was investigated using scanning electron microscope (SEM), glancing angle X-ray diffraction (GAXRD), UV–Vis spectrometer, and Mott Schottky analysis. Glancing angle XRD confirmed the presence of wurtzite structure with a preferable orientation around (101) plane, which is of particular interest for many applications. As evidenced by the photoelectrochemical and transient photocurrent measurements, the fabricated Ge-doped ZnO nanorods exhibited enhanced photocurrent (12 mA/cm²) with an exceptional open circuit voltage of ?1.07 V_SCE (?0.416 V_RHE) under AM1.5G illumination, compared to the undoped ZnO based-photoanodes. Moreover, the Ge-doped ZnO nanorods showed unprecedented photoconversion efficiency of 3.6% under AM1.5G illumination. Therefore, the fabricated Ge-doped ZnO nanorods could be a promising conductive photoanode for water splitting.     

Thermodynamic Analysis and Comparison of Performances of Air Standard Atkinson,Otto, and Diesel Cycles with Heat Transfer Considerations

This paper focuses on the overall performances of Otto, Atkinson, and Diesel air standard cycles. This study compares performance of these cycles with regard to parameters such as variable specific heat ratio, heat transfer loss, frictional loss, and internal irreversibility based on finite‐time thermodynamics. The relationship between thermal efficiency and compression ratio, and between power output and compression ratio of these cycles are obtained by numerical examples. In this study, it is assumed that during the combustion process, the heat transfer occurs only through the cylinder wall. The heat transfer is affected by the average temperature of both the cylinder wall and the working fluid. The results show that for each cycle, with the increase of the compression ratio in the specific mean piston speed, power output and thermal efficiency first increase and after reaching their maximum value, start to decrease. The results also indicate that maximum power output and maximum thermal efficiency of an Atkinson cycle could be higher than the values of these parameters in Diesel cycle and Otto cycle in the same operating conditions. The maximum power output and the maximum thermal efficiency of the Otto cycle have the lowest value among studied cycles. By increasing the mean piston speed, power output and thermal efficiency of Atkinson, Diesel, and Otto cycles start to decrease. The results of this study provide guidance for the performance analysis and show the improvement areas of practical Otto, Atkinson, and Diesel engines.     

Volatile compounds characterising Tunisian virgin olive oils: the influence of cultivar

In this work, the volatile profiles of four Tunisian virgin olive oils were established by headspace‐solid phase microextraction and gas chromatography, using flame ionisation and mass spectrometer detectors. More than eighty compounds were isolated and characterised, representing 97–99% of the total GC area. The main volatile compounds present in the oil samples were determined quantitatively, the major constituents were often aldehydes, particularly (E)‐2‐hexenal (48–90%). Significant differences in the content of volatile constituents were observed. These quantitative differences were used to distinguish between virgin olive oils from different varieties.     

Synthesis and characterization of partially crystalline nanosized ZSM-5 zeolites

Partially crystalline nanosize ZSM-5 with high surface area (678 m²/g) was synthesized successfully without using organic template by a two-step temperature process. Aluminum nitrate was used as aluminum source for the first time to synthesize ZSM-5 materials. The presence of MFI structure of the materials was analyzed by XRD, FTIR, Raman spectroscopy and TEM techniques. Addition of commercial HZSM-5 as a seeding agent to the reactants resulted an increase in crystallinity of the ZSM-5 sample and subsequent decrease in specific surface area. The partially crystalline samples exhibited low microporosity and remarkably high meso/macropore volume with pore diameters around 30 nm.     

Genetic Predisposition to Myelodysplastic Syndromes: A Challenge for Adult Hematologists

Myelodysplastic syndromes (MDS) arising in the context of inherited bone marrow failure syndromes (IBMFS) differ in terms of prognosis and treatment strategy compared to MDS occurring in the adult population without an inherited genetic predisposition. The main molecular pathways affected in IBMFS involve telomere maintenance, DNA repair, biogenesis of ribosomes, control of proliferation and others. The increased knowledge on the genes involved in MDS pathogenesis and the wider availability of molecular diagnostic assessment have led to an improvement in the detection of IBMFS genetic predisposition in MDS patients. A punctual recognition of these disorders implies a strict surveillance of the patient in order to detect early signs of progression and promptly offer allogeneic hematopoietic stem cell transplantation, which is the only curative treatment. Moreover, identifying an inherited mutation allows the screening and counseling of family members and directs the choice of donors in case of need for transplantation. Here we provide an overview of the most recent data on MDS with genetic predisposition highlighting the main steps of the diagnostic and therapeutic management. In order to highlight the pitfalls of detecting IBMFS in adults, we report the case of a 27-year-old man affected by MDS with an underlying telomeropathy.