Improved Performances of a Fluidized Bed Photoreactor by a Microscale Illumination System

The performances of a gas-solid two-dimensional fluidized bed reactor in photocatalytic selective oxidation reactions, irradiated with traditional UV lamps or with a microscale illumination system based on UV emitting diodes (UVA-LEDs), have been compared. In the photocatalytic oxidative dehydrogenation of cyclohexane to benzene on catalyst the use of UVA-LEDs modules allowed to achieve a cyclohexane conversion and benzene yield higher than those obtained with traditional UV lamps. The better performances with UVA-LEDs are due to the UVA-LEDs small dimensions and small-angle emittance, which allow photons beam be directed towards the photoreactor windows, reducing the dispersion outside of photoreactor or the optical path length. As a consequence, the effectively illuminated mass of catalyst is greater. We have found that this illumination system is efficient for photo-oxidative dehydrogenation of cyclohexane to cyclohexene on sulphated and ethanol to acetaldehyde on

Managerial input and firm performance. Evidence from a policy experiment

We study the effects of a subsidy program designed to boost small and medium enterprises' export capabilities through a Temporary Export Manager (TEM), hired for at least 6 months to provide consulting on how to reach foreign markets. Firms applied online for the subsidy and vouchers to hire TEMs were allocated on a first-come, first-served basis. We use a difference-in-differences design to compare the performances of firms that nearly got the subsidy with those that barely did not. Eligible firms experienced a large increase in revenues, return on equity, profits and value added per employee, accompanied by a significant growth in export in extra-EU markets four years after receiving the subsidy. The gains were larger for the least productive and smaller firms and effects were heterogeneous across TEM providers. TEMs were also effective in stimulating 'good' labor demand: besides intensifying exports, firms increased their workforce by nearly 13%, mainly in full-time and permanent employees. Results of a survey conducted on TEM providers confirm our econometric results and revealed that the benefits of voucher extended beyond the initial subsidized service

Bioalcohol Reforming: An Overview of the Recent Advances for the Enhancement of Catalyst Stability

The growing demand for energy production highlights the shortage of traditional resources and the related environmental issues. The adoption of bioalcohols (i.e., alcohols produced from biomass or biological routes) is progressively becoming an interesting approach that is used to restrict the consumption of fossil fuels. Bioethanol, biomethanol, bioglycerol, and other bioalcohols (propanol and butanol) represent attractive feedstocks for catalytic reforming and production of hydrogen, which is considered the fuel of the future. Different processes are already available, including steam reforming, oxidative reforming, dry reforming, and aqueous-phase reforming. Achieving the desired hydrogen selectivity is one of the main challenges, due to the occurrence of side reactions that cause coke formation and catalyst deactivation. The aims of this review are related to the critical identification of the formation of carbon roots and the deactivation of catalysts in bioalcohol reforming reactions. Furthermore, attention is focused on the strategies used to improve the durability and stability of the catalysts, with particular attention paid to the innovative formulations developed over the last 5 years

Low-Voltage GaN Based Inverter for Power Steering Application

In the paper, an experimental evaluation of a low voltage Gallium Nitride (GaN) based inverter suitable for power steering application is presented. The inverter switches belong to the last generation of low voltage enhancement-mode normally-off GaN Field-Effect Transistor (FET). The main advantage in the usage of these devices is the high switching frequency capability with consequently volume reduction of the passive components. On the other hand, the layout and the device packaging solution are a challenge to reduce the parasitic inductances. Furthermore, the dv/dt increasing with the switching frequency need a deep investigation in a motor drive application. The paper deals with the advances and drawbacks of the GaN FETs in two-level Pulse Width Modulation (PWM) motor drive applications providing a piece of detailed experimental evidence and design guidelines

The protective effect of M40401, a superoxide dismutase mimetic, on post-ischemic brain damage in Mongolian gerbils

BACKGROUND: Overproduction of free radical species has been shown to occur in brain tissues after ischemia-reperfusion injury. However, most of free radical scavengers known to antagonize oxidative damage (e.g. superoxide dismutase, catalase), are unable to protect against ischemia-reperfusion brain injury when given in vivo, an effect mainly due to their difficulty to gain access to brain tissues. Here we studied the effect of a low molecular weight superoxide dismutase mimetic (M40401) in brain damage subsequent to ischemia-reperfusion injury in Mongolian gerbils. RESULTS: In animals undergoing ischemia-reperfusion injury, neuropathological and ultrastructural changes were monitored for 1–7 days either in the presence or in the absence of M40401 after bilateral common carotid artery occlusion (BCCO). Administration of M40401 (1–40 mg/kg, given i.p. 1 h after BCCO) protected against post-ischemic, ultrastructural and neuropathological changes occurring within the hippocampal CA1 area. The protective effect of M40401 was associated with a significant reduction of the levels of malondialdehyde (MDA; a marker of lipid peroxidation) in ischemic brain tissues after ischemia-reperfusion. CONCLUSION: Taken together, these results demonstrate that M40401 provides protective effects when given early after the induction of ischemia-reperfusion of brain tissues and suggest the possible use of such compounds in the treatment of neurological dysfunction subsequent to cerebral flow disturbances

Enjoy your journey: the bergamot polyphenols from the tree to the cell metabolism

No abstract availabl

Immobilization of Saccharomyces cerevisiae cells by adhesion to polymeric matrices obtained by radiation-induced polymerization

An immobilization method based on the spontaneous adhesion of invertase-active cells of yeast (Saccharomyces cerevisiae) to tuff granules was described by Parascandola, Scardi, and Tartaglione. Compared with gel entrapment, immobilization by adhesion is much more simple and free from diffusional limitations. However, adhesion is a rather complicated process involving surface interactions between microbial cells and the so-called substratum, that is, the solid support to which they attach. Because there are still many unanswered questions about the mechanism of adhesion, the selection of suitable substrata for a given microbial species can be made only empirically. Thus, to find substrata better than tuff or insolubilized gelatin, polymeric hydrogels that were obtained by radiation-induced polymerization below 0 °C and that were employed successfully for immobilizing enzymes, cells and antibodies were considered. A dozen of such polymer matrices with different hydrophilicities were synthesized and assayed as possible substrata for S. cereviisae cells used in continuous ethanol production