optimization of solar integration in biomass fuelled steam plants

Abstract This paper is focused on solar-biomass integration and presents a thermodynamic analysis of solar power utilization replacing the steam bleeds of a regenerative Hirn cycle plant, biomass fuelled, in feedwater pre heating process. In solar-biomass integrated configuration an energy conversion efficiency of solar energy has been evaluated in order to compare the use of solar energy in solo and hybrid configurations. Such efficiency has been adopted as optimization parameter for the best hybrid plant configuration, varying steam pressure and regeneration parameters

Structural and biochemical characterization of a new type of lectin isolated from carp eggs.

A previously unidentified glycoprotein present in the eggs of the carp (Cyprinus carpio) was isolated and structurally characterized. The protein binds to a Sepharose 4B matrix and can be eluted with 0.4 M N-acetylglucosamine. The protein has an apparent molecular mass of 26686.3 Da. On the basis of gel-filtration chromatography, the protein appears to be present in solution as a monomer. The sequence of its 238 amino acids, the position of its four disulphide bridges and the composition of its single N-linked carbohydrate chain were determined. The lectin shows a very low agglutinating activity for human A-type erythrocytes and interacts with both Gram-positive and -negative bacteria. These latter interactions are inhibited by N-acetylglucosamine. A database search shows that its amino acid sequence is similar to that of the members of an invertebrate lectin family that includes tachylectin-1. Tachylectin-1 is present in the amoebocytes of the horseshoe crab, Tachypleus tridentatus, and plays a role in the innate defence system of this species. Homologous genes are also present in other fish, having 85% identity with a gene expressed in the oocytes of the crucian carp (Carassius auratus gibelio) and 78% identity with a gene in the cDNA library of the zebrafish (Danio rerio)

A Hybrid Screen-Printed Strip for Enhanced Electroanalysis towards Lead and Cadmium in Multi-Matrices

Although heavy metals represent a major treat for ecosystem and human health, reference methods for their monitoring are characterized by time-consuming procedures, skilled personel and sophisticated equipment (e.g. ICP-MS, AAS). The development of portable solutions is required, particularly improving interventions and reducing complexity. To this regards, an electrochemical strip for the determination of lead and cadmium in clinical, environmental and food matrices have been developed. The Bismuth film-based flexible device has been optimized and it has been able to detect cadmium and lead, respectively, down to the detection limit of 1.3 and 2 ppb. The use of Whatman No.1 chromatographic paper has allowed to improve the sensitivity towards the detection of heavy metals, because of the porosity that allowed to pre-concentrate species. This led to an improvement in the sensitivity, with a detection limit of 0.3 and 0.5 ppb, respectively, to cadmium and lead, and offers the possibility to tune the sensitivity according to needs, e.g., improving the number of pre-concentration steps. Subsequently, the application of the electrochemical sensor in drinking water, mussel and blood serum was evaluated, demonstrating how these hybrid polyester-paper electrochemical strips can significantly lower the time and costs for on-site measurements, through analytical methods of simple use. The accuracy has been evaluated by comparison with ICP-MS measurements, giving satisfactory results

Advanced Image Analysis of Two-Phase Flow inside a Centrifugal Pump

The analysis two-phase flow inside centrifugal pumps is a fundamental issue in several engineering applications. This often represents a bad working condition with respect to single phase one, causing head reduction, efficiency decrease, and higher operational costs in terms of energy and money. The paper reports a numerical analysis of bubbles behavior inside centrifugal pumps. Equations regulating the air bubble motion within the rotor of a centrifugal pump have been solved considering the effects of all forces acting. Coalescence phenomena have been investigated too, in order to identify how gas zone presence in the rotor can lead to anomalous working condition. Results are reported in graphs and diagrams varying bubble dimension and water flow rate. An experimental approach to visualize the two-phase flow field inside the impeller is presented too. Images have been acquired, elaborated, compared with numerical results, and discussed in order to understand the interaction between gas phase and liquid phase and to correlate this behavior with the energy dissipation phenomena for a centrifugal pump

Direct interactions among Ret, GDNF and GFRalpha1 molecules reveal new insights into the assembly of a functional three-protein complex.

The glial-cell-line-derived neurotrophic factor (GDNF) ligand activates the Ret receptor through the assembly of a multiprotein complex, including the GDNF family receptor α1 (GFRα1) molecule. Given the neuroprotective role of GDNF, there is an obvious need to precisely identify the structural regions engaged in direct interactions between the three molecules. Here, we combined a functional approach for Ret activity (in PC12 cells) to cross-linking experiments followed by MS-MALDI to study the interactions among the purified extracellular region of the human Ret, GDNF and GFRα1 molecules. This procedure allowed us to identify distinct regions of Ret that are physically engaged in the interaction with GDNF and GFRα1. The lack of these regions in a recombinant Ret form results in the failure of both structural and functional binding of Ret to GFRα1/GDNF complex. Furthermore, a model for the assembly of a transducing-competent Ret complex is suggeste

Altered Expression of Protamine-like and Their DNA Binding Induced by Cr(VI): A Possible Risk to Spermatogenesis?

Chromium (VI) is the most dangerous oxidation state among the stable forms of chromium. In this work, we evaluated the effect of exposing Mytilus galloprovincialis for 24 h to 1, 10, and 100 nM chromium (VI) on the properties of Protamine-like (PLs) and their gene levels in the gonads. Specifically, we analyzed, by AU-PAGE and SDS-PAGE, PLs extracted from unexposed and exposed mussels. In addition, via EMSA, we evaluated the ability of PLs to bind DNA and also verified their potential to protect DNA from oxidative damage. Finally, we assessed possible alterations in gonadal expression of mt10, hsp70, and genes encoding for PLs-II/PL-IV and PL-III. We found that for all experimental approaches the most relevant alterations occurred after exposure to 1 nM Cr(VI). In particular, a comigration of PL-II with PL-III was observed by SDS-PAGE; and a reduced ability of PLs to bind and protect DNA from oxidative damage was recorded. This dose of chromium (VI) exposure was also the one that produced the greatest alterations in the expression of both mt10 and PL-II/PL-IV encoding genes. All of these changes suggest that this dose of chromium (VI) exposure could affect the reproductive health of Mytilus galloprovincialis

Іконографічні особливості образу Богородиці в східній християнській традиції: релігієзнавчий аспект

Стаття присвячена аналізу іконографічних особливостей образу Богородиці в православній традиції. Розглянуто особливості іконографічного зображення, його відмінність від зображення у творі мистецтва. Проаналізовано чотири основні іконографічні типи й варіанти ікон Богородиці. Показано, що характерною рисою всіх типів ікон Богородиці є їхня христоцентричність та самостійність як духовного атрибута богоспілкування.In the article is analyzed the iconographic features of the Virgin in the Orthodox tradition. The author argues that Christocentric is the main characteristic of the icons of the Virgin