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Optimal amounts of CO2 are added to syngas to boost the methanol synthesis rate on Cu-ZnO-Al2 O3 in the industrial process. The reason for CO2 promotion is not sufficiently understood at the particle level due to the catalyst complexity and the high demands of characterization under true reaction conditions. Herein, we applied operando synchrotron X-ray powder diffraction and modulated-excitation infrared spectroscopy on a commercial catalyst to gain insights into its morphology and surface chemistry. These studies unveiled that Cu and ZnO agglomerate and ZnO particles flatten under CO/H2 and/or CO2 /H2 . Under the optimal CO/CO2 /H2 mixture, sintering is prevented and ZnO crystals adopt an elongated shape due to the minimal presence of the H2 O byproduct, enhancing the water-gas shift activity and thus the methanol production. Our results provide a rationale to the CO2 promotion emphasizing the importance of advanced analytical methods to establish structure-performance relations in heterogeneous catalysis.

Calcium carbonate is a model system to investigate the mechanism of solid formation by precipitation from solutions, and it is often considered in the debated classical and non-classical nucleation mechanism. Despite the great scientific relevance of calcium carbonate in different areas of science, little is known about the early stage of its formation. We, therefore, designed contactless devices capable to provide informative investigations on the early stages of the precipitation pathway of calcium carbonate in supersaturated solutions using classical scattering methods such as Wide-Angle X-ray Scattering (WAXS) and Small-Angle X-ray Scattering (SAXS) techniques. In particular, SAXS was exploited for investigating the size of entities formed from supersaturated solutions before the critical conditions for amorphous calcium carbonate (ACC) nucleation are attained. The saturation level was controlled by mixing four diluted solutions (i.e., NaOH, CaCl2, NaHCO3, H2O) at constant T and pH. The scattering data were collected on a liquid jet generated about 75 sec after the mixing point. The data were modeled using parametric statistical models providing insight about the size distribution of denser matter in the liquid jet. Theoretical implications on the early stage of solid formation pathway are inferred.

Few data are available on cognitive and psychiatric effects of topiramate (TPM) monotherapy in migraine. Twenty patients affected by migraine were treated with TPM monotherapy. At the same time, twenty control subjects were selected. A comprehensive neuropsychological and behavioural battery of tests were performed at baseline (T0), at titration (T1) and in maintenance period (T2). Topiramate serum levels were also investigated at T1 and T2. On comparison with the control group, no cognitive and psychiatric differences were detected at baseline. A significant reduction of word fluency score (P < 0.05) was evident after TPM treatment, both at T1 and T2. No patient developed psychiatric adverse events. TPM induced an impairment of verbal fluency and no psychiatric adverse events, demonstrating selective negative cognitive profile in migraine therapy. Slow titration, low doses, lack of previous psychiatric disorders and/or familial history may explain our data.

Samples made of an isotropically oriented ensemble of atomic clusters or structures that are not large crystals (i.e. extended less than 10 periods in each direction) are at the frontier of today's material science and chemistry. Examples are nanoparticles, nanotubes, amorphous matter, polymers, and macromolecules in suspension. For such systems the computation of powder diffraction patterns (which may provide an efficient characterization) is to be performed the hard way, by summing contributions from each atom pair. This work deals with performing such computation in the most practical and efficient way. Three main points are developed: how to encode the enormous array of interatomic distances (which increase as the square or higher powers of the cluster diameter) to a much smaller array of equispaced values on a coarse grid (whose size increases linearly with the diameter); how to perform a fast computation of the diffraction pattern from this equispaced grid; how to optimize the grid step to obtain an arbitrarily small error on the computed diffraction pattern. Theory and examples are jointly developed and presented.

Title compounds with Ln: Dy, Ho, Er, Tm, Yb, and Lu are synthesized from stoichiometric mixtures of Ln2O3, BaFe2O4, Fe2O3, and Fe (1100 °C, 24 h) and from solutions of Ln2O3, BaCO3, and Fe(C2O4) in molten citric acid, followed by calcination (900 °C for 6 h and 1050 °C for 24 h).

Twenty-one evaluable patients with FIGO stages II-IV epithelial ovarian cancer, median age 57 (range 47-75 years), were treated with ifosfamide (IF), 3 g/m2 diluted in 500 ml saline solution, 8 hour intravenous (i.v.) infusion on days 1-5; mesna 20% of IF dose, i.v. bolus injection, was given at hours 0 and 4; mesna 40% of IF dose by oral route at hours 8 and 12, days 1-5; plus cisplatin 20 mg/m2 diluted in 500 ml saline solution, 2 hour i.v. infusion, days 1-5. Cycles were repeated every 4 weeks. All patients had metastatic lesions (mesentery, pleura, colon, cervix, abdominal wall, lung, liver, bladder, and nodes). Toxicity ranged from mild to moderate. All patients experienced alopecia, nausea, and vomiting. Neutropenia and anemia ranged from mild to moderate. One patient experienced mild brain confusion and two patients microscopic hematuria. Ten clinically complete responses (47%) and five clinically partial responses (23%) were registered, for an overall 70% objective response. However, after a second look performance in 10 patients with clinically complete response, six of 10 patients showed a pathological complete response and four showed pathological partial response. The median duration of complete response is about 33 months, and median partial response duration is 14 months. Although the numbers are small, these data indicate that combination chemotherapy with high dose ifosfamide/mesna plus cisplatin may be an active treatment for advanced ovarian carcinoma.