The Origin of the High Voltage in DPM12/P3HT Organic Solar Cells

Organic solar cells made using a blend of DPM12 and P3HT are studied. The results show that higher V_oc can be obtained when using DPM12 in comparison to the usual mono‐substituted PCBM electron acceptor. Moreover, better device performances are also registered when the cells are irradiated with sun‐simulated light of 10–50 mW cm^?2 intensity. Electrochemical and time‐resolved spectroscopic measurements are compared for both devices and a 100‐mV shift in the density of states (DOS) is observed for DPM12/P3HT devices with respect to PCBM/P3HT solar cells and slow polaron‐recombination dynamics are found for the DPM12/P3HT devices. These observations can be directly correlated with the observed increase in V_oc, which is in contrast with previous results that correlated the higher V_oc with different ideality factors obtained using dark‐diode measurements. The origin for the shift in the DOS can be correlated to the crystallinity of the blend that is influenced by the properties of the included fullerene.     

Gas Sensing of NiO‐SCCNT Core–Shell Heterostructures: Optimization by Radial Modulation of the Hole‐Accumulation Layer

Hierarchical core–shell (C–S) heterostructures composed of a NiO shell deposited onto stacked‐cup carbon nanotubes (SCCNTs) are synthesized by atomic layer deposition (ALD). A film of NiO particles (0.80–21.8 nm in thickness) is uniformly deposited onto the inner and outer walls of the SCCNTs. The electrical resistance of the samples is found to increase of many orders of magnitude with the increasing of the NiO thickness. The response of NiO–SCCNT sensors toward low concentrations of acetone and ethanol at 200 °C is studied. The sensing mechanism is based on the modulation of the hole‐accumulation region in the NiO shell layer upon chemisorption of the reducing gas molecules. The electrical conduction mechanism is further studied by the incorporation of an Al₂O₃ dielectric layer at NiO and SCCNT interfaces. The investigations on NiO–Al₂O₃–SCCNT, Al₂O₃–SCCNT, and NiO–SCCNT coaxial heterostructures reveal that the sensing mechanism is strictly related to the NiO shell layer. The remarkable performance of the NiO–SCCNT sensors toward acetone and ethanol benefits from the conformal coating by ALD, large surface area of the SCCNTs, and the optimized p‐NiO shell layer thickness followed by the radial modulation of the space‐charge region.     

Training,research, and technical assistance to improve the water resources management in Southern Italy — The experience of CSEI Catania

Water resources management may be improved through the activities of organizations devoted to practice-oriented research, continuing education, and technical assistance. The experience carried out in southern Italy by CSEI Catania during 13 years of activity is presented. Two main activities are discussed: the research and training program on regional pollution control plans and the development of a water data bank.     

Cranberry and Recurrent Cystitis: More than Marketing?

Epidemiologic studies indicate that millions of people suffer from recurrent cystitis, a pathology requiring antibiotic prophylaxis and entailing high social costs. Cranberry is a traditional folk remedy for cystitis and, which, in the form of a variety of products and formulations has over several decades undergone extensive evaluation for the management of urinary tract infections (UTI). The aim of this retrospective study is to summarize and review the most relevant and recent preclinical and clinical studies on cranberries for the treatment of UTIs. The scientific literature selected for this review was identified by searches of Medline via PubMed. A variety of recent experimental evidence has shed light on the mechanism underlying the anti-adhesive properties of proanthrocyanidins, their structure–activity relationships, and pharmacokinetics. Analysis of clinical studies and evaluation of the cranberry efficacy/safety ratio in the prevention of UTIs strongly support the use of cranberry in the prophylaxis of recurrent UTIs in young and middle-aged women. However, evidence of its clinical use among other patients remains controversial.     

Triple diffusive convection in porous media

The presence of more than one chemical dissolved in fluid mixtures is very often requested for describing natural phenomena (contaminant transport, underground water flow, acid rain effects, worming of the stratosphere). In the present paper, a triple convective-diffusive fluid mixture saturating a porous horizontal layer, heated from below and salted from above and below, is studied. In closed forms, conditions sufficient for (i) inhibiting the onset of convection and (ii) guaranteeing the global nonlinear stability of the thermal conduction solution and the absence of subcritical instabilities are obtained.     

ECT benchmark results for 3D defect signatures in industrial applications

This paper is focused on the Eddy Current Testing (ECT) method applied to important industrial applications such as the inspection of tubes in nuclear power plants and the inspection of planar surface from aeronautical industry. Specifically, we consider the prediction of the signatures produced by small defects through two fully three-dimensional numerical models developed for ECT. In particular we consider the responses to small defects described in two experimental benchmarks from nuclear power industry and one experimental benchmark from aeronautical applications. Despite of the small size of the defects that, in some cases, is of the order of few millimetres, the numerical models reproduce correctly the experimental responses provided in the benchmarks, including the challenging case of a defect (in a tube) close to the support plate.     

Photochromic Polymers Based on the Photoinduced Opening and Thermal Closing of [1,3]Oxazine Rings

Two macromolecular constructs incorporating a single polymer backbone with multiple photochromic side chains are developed. Both systems are prepared from preformed photochromic [1,3]oxazines after the ring‐opening polymerization of their norbornene appendages. In solution, UV illumination of these polymers opens the [1,3]oxazine rings in their side chains in less than 6 ns and with a quantum yield of 0.09 in both instances. The photogenerated species incorporate a 4‐nitrophenolate chromophore, and hence, their formation is accompanied by the appearance of an intense band in the visible region of the absorption spectrum. The photoproducts revert spontaneously to the original state with first‐order kinetics in microseconds. Furthermore, both photochromic polymers tolerate hundreds of switching cycles with no sign of degradation, even in the presence of molecular oxygen. Thus, this design logic and choice of functional building blocks can translate into the realization of innovative photoresponsive materials with excellent photochromic performance.     

Theoretical and Experimental Analysis of a Laser Textured Thrust Bearing

In this article, a laser partially textured thrust bearing is theoretically and experimentally analyzed. An adiabatic model is developed in order to theoretically investigate the performances of the bearing. The bearing sample is partially textured both in radial and circumferential direction using the laser texturing process. The performance of the bearing (fluid film thickness and friction torque) is evaluated on a specially adapted test rig and the experimental results are compared with the theoretical model. A good agreement is found between the theoretical model and the experimental data. Also a comparison between a laser textured bearing and a bearing textured using the photolithographic method is presented.     

Morphology and lectin‐binding sites of pyloric caeca epithelium in normal and GnRH‐treated Atlantic bluefin tuna (Thunnus thynnus) Linnaeus 1758

Mucosal epithelium of pyloric caeca was studied in normal and in GnRH‐treated Atlantic bluefin tuna Thunnus thynnus L., using morphological analysis, conventional and lectin glycohistochemistry. The lining epithelium consisted of columnar (absorptive) cells, goblet cells and intraepithelial leucocytes. The epithelium from normal animals was significantly taller than GnRH‐treated samples. Conventional histochemistry displayed the same staining pattern in normal and hormone‐treated specimens which showed a mixture of neutral and sulphated acidic glycoconjugates in the luminal surface and goblet cells, and neutral glycans in apical granules of enterocytes. Lectin histochemistry revealed a different glycoconjugate pattern in normal and GnRH‐treated tunas. In normal specimens the luminal surface expressed sialoglycoconjugates which bound MAL II, SNA, KOH‐sialidase‐PNA, KOH‐sialidase‐SBA as well as asialoglycans stained with HPA, SBA, GSA I‐B₄, LTA. N‐linked glycans were highlighted by Con A and KOH‐sialidase‐WGA. In GnRH‐treated tunas the luminal surface did not react with SNA, SBA and LTA. The columnar cells of normal tunas bound KOH‐sialisase‐PNA in the apical region, KOH‐sialidase‐PNA, KOH‐sialidase‐DBA, HPA, SBA, KOH‐sialidase‐SBA and KOH‐sialidase‐WGA in apical granules, GSA I‐B₄ and LTA in the supranuclear region. GnRH‐treated specimens showed some columnar cells that stained with KOH‐sialidase‐WGA in the apical granules and with GSA I‐B₄ in the supranuclear region. The goblet cells of normal animals produced mucins positive to PNA, HPA, KOH‐sialidase‐DBA, SBA, GSA II. The latter three binding sites lacked in GnRH‐treated tunas. The results suggest that the mucosal epithelium of Thunnus thynnus L. pyloric caeca expresses a complex glycan pattern that is affected by GnRH‐treatment. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc.     

Numerical Studies on the Seismic Retrofit of Bridges Using Shape Memory Alloys

Recent earthquakes have highlighted the seismic vulnerability of bridges due to excessive movements at the joints (in simply supported deck bridges) or concentration of seismic forces in a few piers (in multi-span continuous deck bridges). Steel-based seismic restrainers and viscous shock transmitters are used to limit the joint openings in simply supported deck bridges or to redistribute the seismic force among all piers in continuous deck bridges, respectively. Currently used devices, however, have some limitations such as large dimensions, no energy dissipation, possible large residual displacements, bad control of the force transmitted to the substructure (steel restrainers), large dimensions, difficulty of installation in existing structures, need of maintenance, and sensitivity to the earthquake characteristics (viscous shock transmitters). Shape memory alloys (SMAs) with superelastic behavior show the potential to overcome the limitations involved in the current technologies. In this article, a multi-performance seismic device based on superelastic SMA wires is proposed for the seismic retrofit of multi-span simply supported and continuous deck bridges. The effectiveness of the SMA devices is assessed through a number of nonlinear time-history analyses on two bridge structures representative of existing Italian highway bridges. Results are compared to the seismic response of the bridges in the as-built configuration.