Biogas upgrade to syngas through thermochemical recovery using exhaust gas reforming

Exhaust gas fuel reforming has been examined as a process for upgrading biogas into hydrogen enriched gaseous fuel for use in transportation. The effect of different O2/CH4 mole ratios and space velocities on the reformer product has been studied. In addition, 20% volume fraction of exhaust gas recirculation (EGR) has been introduced into the engine system to investigate the effect of engine-out exhaust composition on the reforming process. Our results imply that fuel reforming process efficiencies of up to 95% (based on the energy content of the reformate produced compared to the energy content of the biogas used) can be achieved at optimum biogas and engine exhaust gas ratios for the different engine conditions. Furthermore, the total carbon dioxide content is reduced by reforming biogas to form better quality fuel

Biological Atomic Force Microscopy for Imaging Gold-Labeled Liposomes on Human Coronary Artery Endothelial Cells

Although atomic force microscopy (AFM) has been used extensively to characterize cell membrane structure and cellular processes such as endocytosis and exocytosis, the corrugated surface of the cell membrane hinders the visualization of extracellular entities, such as liposomes, that may interact with the cell. To overcome this barrier, we used 90 nm nanogold particles to label FITC liposomes and monitor their endocytosis on human coronary artery endothelial cells (HCAECs) in vitro. We were able to study the internalization process of gold-coupled liposomes on endothelial cells, by using AFM. We found that the gold-liposomes attached to the HCAEC cell membrane during the first 15–30 min of incubation, liposome cell internalization occurred from 30 to 60 min, and most of the gold-labeled liposomes had invaginated after 2 hr of incubation. Liposomal uptake took place most commonly at the periphery of the nuclear zone. Dynasore monohydrate, an inhibitor of endocytosis, obstructed the internalization of the gold-liposomes. This study showed the versatility of the AFM technique, combined with fluorescent microscopy, for investigating liposome uptake by endothelial cells. The 90 nm colloidal gold nanoparticles proved to be a noninvasive contrast agent that efficiently improves AFM imaging during the investigation of biological nanoprocesses

Optimization of Polycrystalline CVD Diamond Seeding with the Use of sp³/sp² Raman Band Ratio

The influence of various nanodiamond colloids used for seeding nondiamond substrates in microwave plasma enhanced chemical vapour deposition diamond process was investigated. Colloids based on deionized water, isopropanol alcohol and dimethyl sulfoxide (DMSO) were used with different grain size dispersion: 150, 400 and 35 nm, respectively. The influence of growth time was also taken into consideration and bias enhanced nucleation. Microcrystalline diamond films were deposited on the seeded substrates in microwave plasma chemical vapour deposition using hydrogen-methane gas mixture. Seeding efficiency was investigated by means of scanning electron microscopy and Raman spectroscopy. Authors defined the new factor called as diamond ideality factor (di) which can give a quick estimation of quality of film and relative sp³ content. Few main peaks were identified at the following wave numbers: diamond sp³ peak 1332 $cm^{-1}$, D band peak 1355 $cm^{-1}$, C-H bending peak 1440-1480 $cm^{-1}$ and G band peak 1560 $cm^{-1}$. The best di was achieved for DMSO based colloid in all cases. The application of bias enhanced nucleation increases the diamond crystals size and the sp³/sp² ratio