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Sonochemistry is based on acoustic cavitation, which consist in the formation, growth, and implosive collapse of bubbles within a liquid. Collapsing bubbles generate localized hot spots, characterized by temperatures up to 5000 K and pressures up to 1800 atm. These extreme conditions allow producing a variety of nanostructured and amorphous materials, as well as they are advantageous for chemical processes. Ultrasound requires inexpensive equipment and fewer steps than conventional methods. Combining ultrasound and photocatalysis enhances the performance of the processes, reduces reaction time, avoids the use of extreme physical conditions and improves the photocatalytic materials properties increasing their activity. Here, we reported the positive effect of US in synthesizing Me-modified TiO

The ingredients of Pharmaceuticals and Personal Care Products (PPCPs) persist in water and conventional treatment plants are not able to remove them efficiently. Sonochemical treatment is insufficient to mineralize organics such as ibuprofen into CO

Titanium dioxide is the most popular photocatalyst to degrade organic pollutants in air, as well as in water. The principal drawback preventing its commercial application lies in its limited absorption of the visible light (400-700nm), while it is active under UV irradiation (≤387nm). Supporting noble metals in the form of nanoparticles on TiO

Strong Lewis acidity of a phase-pure γ-Ga2O3 was studied by the adsorption of CO at ambient temperature, with the combined use of adsorption microcalorimetry and in situ Fourier transform infrared ...

We report the preparation and the structural and morphological characterization of the perovskite compound NdSr2RuCu2Oy. The crystal structure of this material has been determined by a combined high-resolution electron microscopy, selected area electron diffraction and high-resolution X-ray powder diffraction study. The morphology of the samples has been monitored by a scanning electron microscope equipped with an energy dispersive spectrometer attachment by which the microanalysis of the crystallites has been also performed. Finally, dc magnetic susceptibility measurements show that this compound behaves like an enhanced paramagnetic metal with evidence of neither magnetic order and neither superconducting one.

In this work, the surface properties of imogolite are studied, in terms of type, acidic strength, accessibility and stability of hydroxyls groups. Imogolite nanotubes present interesting surface features, in that the outer surface is covered by Al(OH)Al groups and an inner surface lined by isolated ≡SiOH groups. The knowledge of the acidic strength and of the actual accessibility, for example to reactants in a acidic-catalyzed reaction, is of paramount importance for any practical application. Being an hydrated alumino-silicate, the behaviour of imogolite surface resulted to be very sensitive to the pre-treatment temperature: experimental results showed that molecular water is removed only at 300°C, rendering inner silanols accessible to probes like CO, methanol and even phenol. Inner silanols are as acidic as those at the surface of amorphous silica, but the presence of plenty of them at the inner surface enhance the interaction with the adsorbed molecules, thus hindering diffusion. At higher pre-treatment temperatures (500°C), the nanotubes structure is lost, with formation of a lamellar phase, which, interestingly, shows new stronger acidic properties, resembling those of amorphous alumino-silicates with high Al content.

The every-day problem represented by the coexistence of several overlapped components in a narrow spectral range is treated. A home-made deconvolution program (Asymgrad) has been developed in order to deal with this problem. Asymgrad is able to perfom spectral deconvolutions into up to 13 peaks. The number of peaks, their analytical dependence and their symmetry can be defined by the user. The application of this software to some IR spectra of adsorbed species is presented and discussed in detail; particular attention is devoted to the description of the proper use of this complex deconvolution facility. Examples are reported showing the way to escape some deconvolution traps.

For vehicle Original Equipment Manufactures (OEMs), road noise inside the vehicle is an important aspect that contributes to the comfort and the sound quality image of the vehicle. Road noise inside a vehicle is a function of the source (tire design interacting with road surface) and of vehicle sensitivity functions. Road noise targets and tire targets are typically developed by characterizing the tire as a noise and/or vibration source and by characterizing the vehicle as a matrix of acoustic or structural paths (1) . This paper focuses on the development of a simplified procedure for measurement of Noise Reduction (or acoustic vehicle sensitivity function) from tire patch to vehicle interior. Several procedures are available from either literature, vehicle manufacturers or software providers, which exhibit important differences regarding sound production, number and position of source and receiver microphones, or measured parameters (2) . The objective of the investigation described in this paper was to evaluate these different procedures and identify the simplest one that can provide data that can be used to simulate, with a reasonable accuracy, the noise reduction effect of a vehicle. Tests of Noise Reduction were conducted in a hemi-anechoic chamber on a production vehicle with the following methods: point source, reciprocity with volume velocity source, ad-hoc tire-patch speaker (grate box) and off-the-shelf loudspeakers. The averaged Noise Reduction (NR) functions between a binaural head inside the vehicle and each of the four tires were computed using each method. These functions were applied to time data acquired in vehicle, on a chassis dynamometer, to validate the prediction of interior noise by comparison to measured noise. The paper describes the test methods, their comparison and includes the authors’ recommendations for best method.

Some studies have previously suggested the involvement of antibodies directed against CD36 (anti-CD36) in the pathogenesis of thrombosis. The aim of this study was to evaluate the prevalence of anti-CD36 in patients with antiphospholipid antibodies (aPL) and its relationship with thrombosis.Anti-CD36 were tested using an indirect MAIPA assay in 62 patients with autoimmune aPL but without SLE; there were 38 with and 24 without thrombosis. Nineteen patients with thrombosis served as an aPL(-) control group and 58 healthy subjects as the normal control group.15 of 62 aPL patients (24.2%) but only 1 of 58 (1.7%) normal controls had anti-CD36 (p0.0005). As compared to normal controls, the prevalence of anti-CD36 was significantly higher in aPL patients with (26.3%, p0.0005) or without thrombosis (20.8%, p0.01). Anti-CD36 were significantly more frequent in aPL patients with thrombosis than in thrombosis aPL(-) subjects (26.3% vs 0%, p = 0.02). The presence of anti-CD36 seems to be more frequent in aPL patients with recurrent thrombosis than in those with a single episode (36.8% vs 15.8%).The presence of anti-CD36 is highly prevalent in patients with autoimmune aPL with a trend to being more frequent in patients with recurrent episodes of thrombosis.

In situ FTIR spectroscopy and adsorption microcalorimetry have been employed to study the adsorption/desorption of 2,6-dimethylpyridine (2,6-DMP) on different zirconia and sulfated zirconia (SZ) systems. Adsorption/desorption experiments were carried out at 343 K (beam temperature for all IR experiments) and at 423 K. The adsorbents were (i) a (mainly) monoclinic zirconia, (ii) a crystallographically pure tetragonal zirconia, phase stabilized by formation of a solid solution with 3 mol % Y2O3, (iii) monoclinic sulfated zirconia (m-SZ) and tetragonal sulfated zirconia (t-SZ), both noncalcined and calcined at 923 K, obtained by direct sulfation of the two crystalline ZrO2 specimens, and (iv) two t-SZ specimens (also noncalcined and calcined at 923 K), obtained through the “conventional” sulfation procedure carried out on an amorphous hydroxide precursor and leading, upon thermal treatment at T > 823 K, to crystalline t-SZ. The adsorption/desorption of 2,6-DMP turned out to be a valuable probe for both Brons...

In recent years, the perceived quality of powered seat adjusters based on their sound during operation has become a primary concern for vehicle and seat manufacturers. Historical noise targets based on overall dB(A) at the occupant’s ear have consistently proved inadequate as a measure of the sound quality of a seat adjuster. Significant effort has been devoted to develop alternative sound quality metrics that can truly discriminate between “good” and “bad” seat adjusters. These new metrics have been successfully applied for some years by product development engineers in test labs. However, in the assembly plant the sound quality of the seat adjuster is still assessed subjectively by an operator at the end of the assembly line. The main problem with this approach is not only the lack of consistency and repeatability across large samples of seat tracks, but also the fact that the only feedback provided from the end-of-line to the product development team is of subjective nature. This subjective information is of little help for the engineers who have to diagnose and remedy the problem. Additionally, since sound quality has become one of the main reasons for rejection at the end of the assembly line, there is the need for integrating sound quality performance checks with the standard quality control or functional checks in the manufacturing environment. Therefore, the new challenge for the seat adjuster manufacturer is to implement at the end of the assembly line an automated Sound Quality-based inspection system that relies exclusively on objective parameters. The authors of this paper have devoted a lot of effort toward developing such a system, and this paper will describe and discuss the main issues related to its design, implementation and validation.

This paper presents an integrated design/simulation/test approach for evaluating the sound quality of exhaust noise as early as possible in the exhaust system design and development process. A time domain engine/exhaust simulation program is used to calculate the engine order content of the tailpipe radiated noise from an odd fire V-10 exhaust system. Both steady state and transient conditions are simulated and sound files generated for exhaust sound quality evaluation. To increase the realism of played back sounds, the predicted engine orders are mixed with synthesized or recorded background noise for both steady state and transient conditions. These alternative approaches will be described and evaluated for technical feasibility and sound quality.

To evaluate if the presence of anti-beta 2GPI antibodies (a beta 2GPI) is associated with activated protein C resistance (APC-R) phenotype, we performed the APC-R APTT-based assay in 74 plasma samples from patients with antiphospholipid antibodies (aPL). Samples were diluted 1:5 in factor V-deficient plasma. Lupus anticoagulant (LA), anticardiolipin antibodies (aCL) and a beta 2GPI (IgG and IgM) were also performed. A control group of 22 healthy volunteers was used. The prevalence of reduced APC-R ratio in patients with aPL was significantly higher than in normal controls (31.1 vs 4.5%, P < 0.05) and the mean APC-R ratio was lower (mean +/- SD; 2.32 +/- 0.40 vs 2.55 +/- 0.21, P < 0.02). There were no differences in the prevalence of APC-R and the ratio values between LA(+) and LA(-). Among the LA(+), the aCL(+) had a higher prevalence of APC-R than the aCL(-) (P < 0.01) and lower APC-R ratios (P < 0.01). The latter group was no different to normal controls. Anti-beta 2GPI antibodies were associated with a higher prevalence of APC-R (50.0 vs 19.6%, P < 0.001), and lower APC-R ratios (2.15 +/- 0.41 vs 2.42 +/- 0.35, P < 0.005), compared with a beta 2GPI(-). In conclusion, the acquired APC-R in patients with aPL seems to be associated with aCL and a beta 2GPI rather than an in vitro interference by LA.

In the last decade a great deal of work has been devoted to the characterization of Yttriastabilized tetragonal ZrO2 (YSTZ), because of its large use as a ceramic material. Many efforts have been made to evaluate some macro- and mesoscopic characteristics of YSTZ, such as those obtained by mechanical tests (e. g., shrinkage, sinterability, KIC, specific surface area SSA, etc), whereas only little attention has been focused so far on the evolution of the nanostructural and surface reactivity features of the starting powders. It is normally observed that YSTZ precursors, that have been preliminarly treated in different conditions, exhibit quite different sintering behaviours.

Three specimens of crystalline AlF3, coming from different preparation routes, have been examined: no major differences were found in the spectral region of the (ν3) fundamental mode, whereas the preparation process was observed to introduce appreciable differences in the background spectra that were ascribed to different bulk and surface impurities. Oxidic islands exist both in the bulk and at the surface of all preparations and when AlF3 is derived from non-oxygen-containing precursors. In the latter case, species containing NHx moieties exist, both in the bulk and at the surface. The surface hydrated layer of AlF3 is made up of an extensive ‘regular’ component (i.e. a large amount of undissociated water molecules, coordinated to unsaturated surface AlVI cations), and of an ‘anomalous’ component (i.e. some OH groups that are eliminated upon vacuum activation at relatively low temperatures). The adsorption of pyridine on samples activated by vacuum treatment at temperatures in the range 300–673 K indicates that on all specimens there are variable amounts of ‘irregular’ surface cations [i.e. coordinatively unsaturated surface Al ions with (quasi-)tetrahedral coordination], some of which are strong enough as Lewis-acidic centres to adsorb CO at ambient temperature. Coordinatively unsaturated surface Al ions with the ‘regular’ octahedral coordination are very weakly acidic, as revealed by the end-on adsorption of CO2 at 300 K and by CO uptake at ca. 78 K.

Lobular Neoplasia of the breast, a term which we prefer to that of Lobular Carcinoma in Situ, is a multifocal microscopic entity of uncertain and controversial clinical significance. Lobular Neoplasia is a incidental histological finding among otherwise benign breast biopsies (0.5%-3.5%) depending mainly upon the diagnostic intensity. Its extent is rarely so massive that it makes up a palpable tumor. Although this lesion may be demonstrated at all ages after puberty it occurs most often in premenopausal women. The multicentricity is not below 70% and bilateral occurrence not below 30-35%. Demonstration of Lobular Carcinoma in situ means a 7-12 times greater risk of later developing invasive breast carcinoma as compared with an age corrected general population. Both breast are at risk and about one half of these subsequent carcinomas will develop in the controlateral breast. Attempts at correlating the histological appearances in Lobular Neoplasia with the subsequent occurrence of invasive breast carcinoma have generally be negative. From this data it appears that ipsilateral mastectomy will protect only one half of women with lobular neoplasia who will eventually develop carcinoma and the only surgical approach would perform a bilateral mastectomy. As an alternative to mastectomy, a careful program of frequent follow-up examinations, when possible is preferable.

A CoFe2O4 inverse spinel calcined at two different temperatures (450 and 750 °C), in order to modulate the growth of the crystallites, has been employed in methanol anaerobic oxidation. A correlation between physicochemical properties and catalytic performances of the material has been pursued. The study of both surface and bulk properties has been carried out by means of different experimental techniques, among which are X-ray diffraction (XRD), transmission electron microscopy (TEM), and in situ FTIR spectroscopy. The FTIR study of both bulk and surface spectral features reveals that the calcination step is responsible for the different type of exposed surface sites and as a consequence for the different catalytic behavior. As the use of the spinel as the catalyst for methanol transformation into H2 necessarily implies a regeneration step with steam, in order to recover the oxidative capacity of the solid, both surface and bulk features of the reoxidized solids have been also studied. All results reveal that the two samples, originally morphologically quite different from one another, become very similar after just one redox cycle. Still, it has been also demonstrated that both used materials irreversibly modify their surface properties after the reduction/oxidation process.

In the present work we studied the catalytic production of pure hydrogen from methanol and water using the spinel-type oxide CoFe2O4 (cobalt ferrite) as electron carrier. CoFe2O4 is an interesting material with an inverse spinel structure, and can be readily prepared by co-precipitation of the two oxides in basic media. The final material was obtained by calcinations, and two different calcination temperatures (Tcalc= 450 and 750°C) have been selected, to yield the corresponding CF450 and CF750 samples. A thorough physico-chemical characterization of the materials as a function of Tcalc was carried out. In fact, Tcalc induces some morphological changes in the material, strongly affecting, by aggregation, particles size and so leading to different catalytic performances. Another important aspect, related to Tcalc, seems to be the surface coke deposition, and this phenomenon should be minimized in order to maximize the hydrogen yield. This work is aimed at establishing the influence of both crystal size and carbon deposition on the catalytic performance, in order to improve the stability of the material though several RedOx cycles.

The reactivity of Mg/Me-mixed oxides (Me = Fe, Cr, Al) in m -cresol gas-phase methylation with methanol was studied, with the aim of finding relationships between catalytic performance and surface/bulk features. All systems exhibit similar surface properties (basically due to the presence of basic and Lewis-type acid sites), but the presence of extra cations in the MgO framework affects greatly the products obtained in the mentioned catalytic reaction, depending on the possible co-presence of redox capacity. In particular, (i) the Mg/Al/O system, characterized by no redox capacity, shows catalytic behaviour quite similar to that of conventional Bronsted-type acid catalysts, though with the advantage of exhibiting almost no deactivation during use (a rather common problem for acid catalysts activating methanol for phenol attack ); (ii) the Mg/Cr/O catalyst shows a reactivity typical of a basic catalyst, with high chemo- and regio-selectivity and the favoured formation of 2,5-dimethylphenol; (iii) the Mg/Fe/O system presents a catalytic behaviour closer to that of Mg/Cr/O, if referred to the distribution of phenolic products, but it also exhibits a better activity in methanol dehydrogenation to formaldehyde (that is the true electrophilic reactant for m -cresol ring methylation), and in the decomposition of formaldehyde into light compounds. This behaviour causes a poor selectivity to dimethylphenols with respect to converted methanol, whereas the selectivity with respect to converted m -cresol is not different from that shown by Mg/Cr/O system.

This contribution reports about an in situ FT-IR investigation and the catalytic reactivity of Mg/Me(3+) mixed oxides (Me = Cr, Fe, or Al; Mg/Me = 2, atomic ratio) in the gas-phase methylation of phenol with methanol. It is the second of two papers concerning the mentioned systems, and its purpose is twofold: to confute the classic and not accurate theory concerning the reaction mechanism, and to propose a novel interpretation based on the combined use of catalytic tests and in situ molecular spectroscopy. Results here reported highlight that: (i) the reaction mechanism in phenol methylation, when catalysed by basic systems, is not a classical electrophylic substitution, as generally reported in the literature, but proceeds through the formation of formaldehyde as an intermediate, and (ii) the catalytic behaviour in respect to both methanol and phenol reactants is strictly dependent on catalyst features. Although all investigated systems exhibit a basic-type behaviour with regard to phenol, which dissociates to yield an adsorbed phenolate species, the distribution of phenolic compounds obtained with the Mg/Al/O catalyst was that typically observed with acid catalysts, with prevailing formation of anisole when the reaction was carried out below 350 degrees C and of mono and poly-C-alkylated compounds when the reaction temperature was above 350 degrees C. On the contrary, the reactivity shown by both Mg/Fe/O and Mg/Cr/O systems was that reported in the literature as typical of mixed oxides possessing basic features. The extent of methanol decomposition into light compounds was maximum in the case of Mg/Fe/O catalysts, because of the pronounced redox behaviour typical of Fe(3+) species, whereas neither methanol dehydrogenation nor decomposition were ever observed with Mg/Al/O up to 400 degrees C. Reactivity tests and spectroscopic experiments hinted for methanol dehydrogenation to formaldehyde as the first step in the ring-methylation of phenol with Mg/Cr/O and Mg/Fe/O: in that case, o-cresol and 2,6-xylenol were the only reaction products. But, with Mg/Al/O systems, for which no methanol dehydrogenation occurred, the formation of anisole was due to the synergistic effect of stronger basic features and the presence of Lewis acidic sites, that facilitate the reaction between phenol and methanol after activation over the two different types of catalytic sites.