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An integrated system for converting carbon dioxide to methanol is proposed, and four of its main components (carbon capture absorber, carbon capture stripper, photoreactor, and methanol synthesis reactor) are analyzed thermodynamically, focusing on exergy destruction. The carbon capture unit provides carbon dioxide extracted from industrial flue gas while the photocatalysis unit produces hydrogen from visible light via photocatalytic water splitting. Both, carbon dioxide and hydrogen are supplied to a methanol synthesis reactor at a specific feed rate, temperature and pressure. The thermodynamic analysis shows that the largest exergy destruction rate occurs in the photoreactor (706 kW). The second largest exergy destruction rate occurs in the methanol synthesis reactor (24.7 kW), while the exergy destruction rates are smaller in the carbon capture stripper (23.5 kW) and absorber (17.9 kW). [ABSTRACT FROM AUTHOR]

In this review paper, some novel energy options for clean rail applications are discussed and evaluated. Rail transportation is of strategic importance and therefore a reliable, clean, sufficiently abundant and cost expensive fuel is required. It has been found that integration of selective catalytic reducer and increase of bio-diesel used (including blending with petrochemical diesel) may be an immediate solution which bring some benefits such as up to 50% reduction on environmental impact. However, accounting for the technical feasibility of the solution, the worldwide existence of a well-established infrastructure, high efficiency and lower emissions, the natural gas appears as a key potential option for the railway. Other reviewed technologies include the CNG, LNG-LPG, methanol, ammonia and hydrogen as fuels. Electrical railways represent a solution where large investment is available. Hydrogen, is most likely a solution for the far future, when an infrastructure could be set-up. The life cycle assessment shows high ecological advantages of NG with respect to the baseline diesel with average 15% decrease of environmental impact categories. A novel criterion has been used here to assess the environmental impact which is suitable for pollutant emitting applications such as railway transportation. This criterion is denoted as environmental impingement work of the polluting effluent which is calculated based on the chemical exergy of the polluting species. Chemical exergy is a true measure of the impingement (change, modification) produced by the pollutant on the environment. It is shown that the well-to-wheel environmental impingement of natural gas fuelled locomotive is inferior with at least 15% to diesel-electric locomotive equipped with a selective catalytic reducer. The environmental impact in terms of work impingement on the environment and environmental pollution cost are slightly similar for natural gas, ammonia, methanol and biodiesel fuels. The life cycle environmental impact categories of natural gas locomotive are overall 15% lower than for the conventional diesel-electric locomotive. According to our conclusion, liquefied natural gas is indicated as a prime potential option for clean rail transportation. [ABSTRACT FROM AUTHOR]

Aims: To compare the effects of nebivolol and ramipril on left ventricular hypertrophy in hypertensive patients. Materials and Methods: The study was conducted with a pre-randomised blinded endpoint (PROBE) design in which 106 patients with mild-to-moderate hypertension and left ventricular hypertrophy were randomised to ramipril (n=52) or to nebivolol (n=54) and treated for 39 weeks. The doses of ramipril and nebivolol were 2.5 and 5 mg/day, respectively. After 4-8 weeks, in patients with not normalised diastolic blood pressure, a thiazide diuretic was added (indapamide 2.5 mg or hydrochlorothiazide 12.5 mg/day). In the ramipril group, thiazide diuretic was added in 97% of subjects and in nebivolol group in 92%. The effect of treatment on left ventricular mass was assessed by two-dimensional guided M-mode transthoracic echocardiography, at baseline and at the end of the treatment. Left ventricular mass index (LVMI) was calculated and indexed to body surface area (g/m²) and height2.77 (g/height2.7). Blood pressure (BP) was measured at baseline, after 4, 8, 12, 24 and 39 weeks with a standard mercury sphygmomanometer. Results: Both left ventricular mass (LVM) and mass index (LVMI) decreased significantly after treatment with ramipril (LVMI -14.8 g/m², -7.3 g/height2.7; p < 0.001), and after treatment with nebivolol (LVMI -31.9 g/m², -15.6 g/height2.7; p < 0.001). The difference between ramipril and nebivolol (-17.1 g/m², -8.3 g/height22..77) with regards to reduction of LVMI was statistically significant (p < 0.001). No differences were observed between the two groups in terms of normalization of LVMI. Both drugs decreased BP similarly after 39 weeks of treatment Conclusions: The present study shows that both nebivolol and ramipril decrease LVMI. Nebivolol 5 mg/daily treatment reduced LVMI significantly more than ramipril 2.5 mg/daily. Both drugs similarly decreased BP during the treatment. [ABSTRACT FROM AUTHOR]