Photocatalytic Activity and Mechanical Properties of Cements Modified with TiO2/N

In this paper, studies of the mechanical properties and photocatalytic activity of new photoactive cement mortars are presented. The new building materials were obtained by the addition of 1, 3, and 5 wt % (based on the cement content) of nitrogen-modified titanium dioxide (TiO2/N) to the cement matrix. Photocatalytic active cement mortars were characterized by measuring the flexural and the compressive strength, the hydration heat, the zeta potential of the fresh state, and the initial and final setting time. Their photocatalytic activity was tested during NOx decomposition. The studies showed that TiO2/N gives the photoactivity of cement mortars during air purification with an additional positive effect on the mechanical properties of the hardened mortars. The addition of TiO2/N into the cement shortened the initial and final setting time, which was distinctly observed using 5 wt % of the photocatalyst in the cement matrix

Photocatalytic Activity of TiO

TiO2-WO3 photocatalysts were prepared in a vacuum evaporator by impregnation of TiO2 with WO2 dissolved in an H2O2 solution (30%) and followed by calcination at 400 and 600∘C. XRD analyses showed that at 400∘C monoclinic phase of WO3 was dominated whereas at 600∘C both monoclinic and regular phases of WO3 were present. Modification of TiO2 by WO3 caused increasing in the absorption of light to the visible range. TiO2 and photocatalysts modified with low amount of WO3 (1–5 wt.%) showed high adsorption of Acid Red (AR) on their surface and enhanced photocatalytic activity under UV irradiation. Under visible light irradiation, TiO2-WO3 photocatalysts prepared at 400∘C were more active for AR decomposition than those prepared at 600∘C suggesting that monoclinic phase of WO3 is more active under visible light than regular WO3. Although TiO2-WO3 photocatalysts appeared to be active under visible light for decomposition of AR, the UV irradiation was more efficient

Uncommon branching pattern of the hepatic arteries in a living donor: a case report and brief literature review

Numerous variations of the hepatic arteries are common in surgical patients. We present a 35-year-old woman who was admitted to our department in order to assess possibility of becoming living donor. Preoperative computed tomography scan revealed anomalous branching pattern of the hepatic arteries. In this case right posterior sectoral artery has been given off by the greater pancreatic artery, left hepatic artery has been replaced by the artery arising from the left gastric artery and double segment 4 branches have been observed. To the best of our knowledge, this pattern has not been described in the literature, yet

The Increase of the Micoporosity and CO2 Adsorption Capacity of the Commercial Activated Carbon CWZ-22 by KOH Treatment

The chemical modification of CWZ-22—commercial activated carbon (AC) with KOH‐ to enhance CO2 adsorption was examined. The effect of different impregnation ratios KOH:CWZ-22 from 1 to 4 was studied. The ACs were characterized by CO2 and N2 sorption, Fourier transform infrared (FTIR), SEM, and XRD methods

Model of Enterpreneurship and Social-cultural and Market Orientation of Small Business Owners in Poland

In the development of SMEs in Poland crucial meaning is legislation, steadily adapted to EU regulations, especially to the European Charter for Small Enterprises. Research conducted in Poland by many authors provide data for doing so, to confirm the hypothesis that among small businesses a vital role in shaping their work situation did not continue to play the market mechanisms and orientations, but mainly socio-cultural factors.W rozwoju MŚP w Polsce podstawowe znaczenie mają również uregulowania prawne, systematycznie dostosowywane do regulacji unijnych, zwłaszcza zaś do Europejskiej Karty Małych Przedsiębiorstw. Badania prowadzone w Polsce przez wielu autorów dostarczają danych ku temu, by potwierdzić tezę, że wśród drobnych przedsiębiorców decydującą rolę w kształtowaniu ich sytuacji pracy odgrywają nadal nie mechanizmy i orientacje rynkowe, ale przede wszystkim czynniki społeczno-kulturowe

Hybridization of Advanced Oxidation Processes with Membrane Separation for Treatment and Reuse of Industrial Laundry Wastewater

A new attempt to treat and reuse the industrial laundry wastewater using biological treatment followed by advanced oxidation processes (AOPs) and membrane separation is presented. Three various configurations of the hybrid systems were investigated: (1) biological treatment in a Moving Bed Biofilm Reactor (MBBR) – photocatalysis with suspended TiO2 P25, enhanced with in situ generated O3 – ultrafiltration (UF) – nanofiltration (NF); (2) biological treatment in MBBR– photocatalysis with immobilized TiO2 P25, enhanced with in situ generated O3 – UF - NF; (3) biological treatment in MBBR – photolysis/ozonation (with in situ generated O3) – UF – NF. For comparison purpose the wastewater was additionally treated in the MBBR – UF – NF mode (4). Application of AOPs contributed to the UF membrane fouling mitigation during treatment of the biologically pretreated laundry wastewater. The highest improvement of the UF permeate flux was found in case of the MBBR effluent treated with application of the immobilized TiO2 bed which was attributed to the highest efficiency of mineralization observed for that system. Since the applied wastewater contained significant amounts of inorganic ions, mainly Na+ and Cl-, the NF as the final polishing step was proposed. The quality of NF permeate was independent on the AOP mode applied and, moreover, significantly higher than the quality of water currently used in the laundry. It was concluded that the NF permeate could be recycled to any stage of the laundry system. Taking into consideration that application of TiO2 increases the overall treatment costs and that although the O3/UV pretreatment is less efficient than photocatalysis, it still allows to improve the UF permeate flux for ca. 35% compared to the direct UF of the MBBR effluent, the MBBR – UV/O3 – UF – NF system was proposed as the most beneficial configuration for the treatment and reuse of the industrial laundry wastewater

Phonon and Elastic Instabilities in MoC and MoN

We present several results related to the instability of MoC and MoN in the B1 (sodium chloride) structure. These compounds were proposed as potential superconductors with moderately high transition temperatures. We show that the elastic instability in B1-structure MoN, demonstrated several years ago, persists at elevated pressures, thus offering little hope of stabilizing this material without chemical doping. For MoC, another material for which stoichiometric fabrication in the B1-structure has not proven possible, we find that all of the cubic elastic constants are positive, indicating elastic stability. Instead, we find X-point phonon instabilities in MoC (and in MoN as well), further illustrating the rich behavior of carbo-nitride materials. We also present additional electronic structure results for several transition metal (Zr, Nb and Mo) carbo-nitride systems and discuss systematic trends in the properties of these materials. Deviations from strict electron counting dependencies are apparent.Comment: 5 pages and 4 trailing figures. Submitted to PR