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Environmental impact of fertilizer use and slow release of mineral nutrients as a response to this challenge

.W. Norton & Company. 4. United Nations, Department of Economic and Social Affairs, Population Division, (2013). World Population Prospects: The 2012 Revision , DVD Edition. 5. International Fertilizer Industry Association, Statistics, Market Outlooks; http://www.fertilizer.org/MarketOutlooks.html (accessed Aug 26, 2015). 6. van Cleemput, O., Zapata, F. & Vanlauwe, B. (2008). Use of tracer technology in mineral fertilizer management. In: Guide. Nitr. Managem. Agric. Syst. , Vienna: IAEA. 7. Dobermann, A. (2005). Nitrogen use efficiency - state

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Membrane reactor for enzymatic depolymerization – a case study based on protein hydrolysis

Abstract

The efficiency of enzymatic depolymerization in a membrane reactor was investigated. The model analysis was performed on bovine serum albumin hydrolysis reaction led by three different enzymes, for which kinetic equations have different forms. Comparing to a classic reactor, the reaction yield turns out to be distinctly higher for all types of kinetics. The effect arises from increasing (thanks to the proper selectivity of the applied membrane) the concentration of reagents in the reaction volume. The investigations indicated the importance of membrane selectivity election, residence time and at non-competitive inhibition the substrate (biopolymer) concentration in feed stream. Presented analysis is helpful in these parameters choice for enzymatic hydrolysis of different biopolymers.

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Empirical investigation of two designs of incline solar water desalination system

Empirical investigation of two designs of incline solar water desalination system

This paper presents an experimental investigation of two incline solar water desalination (ISWD) systems. One design uses spray jets for spraying water onto the absorber plate, while the other uses a longitudinal slot for getting the inlet water on the absorber plate. The first ever ISWD system constructed and tested by Aybar et al (2005) used the longitudinal slot with a maximum daily production of 2.995 kg/m2 day. The Aybar et al design produced 3.4 kg/m2-day while the new design produced 6.41 kg/m2-day for wick on absorber plate system day during the hottest months in Famagusta (July-August 2010). Also tested was the influence of porous media (wire mesh), wick on the absorber plate. The effect of number of spray jets used in the system on the daily productivity and efficiency of the systems were also investigated.

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Modification of industrial divinyl rubber by oxidative chlorophosphorylation and assess-ment of metal ion removal efficiency of obtained polymer sorbent

Abstract

The main goal of this study was the preparation of materials containing phosphoric functionalities on the base of industrial polymer - divinyl rubber and the assessment of their removal efficiency of heavy metals from aqueous solutions. The new method concerns the oxidative chlo-rophosphorylation of divinyl rubber by PCl3 with the following modification of obtained inter-mediates to create -PO(OH)2, -OPO(OH)2 groups in the polymer chain. The obtained modified polymers get some new properties such as complex formation and capability for ion exchange. The nature and distribution of phosphoric functionalities in the polymer were studied by the methods of NMRand FTIR- spectroscopy, thermal analysis and scanning electron microscopy. The sorption properties of synthesized polymers towards some cations (Cu+2, Ni+2, Co+2 and Zn+2) from water solutions have been tested. It has been shown that the metal removal efficiency of prepared material depends on pH of medium, initial concentration and type of metal ions.

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Energy efficiency analysis of styrene production by adiabatic ethylbenzene dehydrogenation using exergy analysis and heat integration

Cycle Exergy Analysis of Renewable Energy System. Renew. Energy J. 4, 72–77. DOI: 10.2174/1876387101004010072. 31. Martinaitis, V., Streckiene, G., Biekša, D. & Bielskus, J. (2016). The exergy efficiency assessment of heat recovery exchanger for air handling units, using a state property – Coenthalpy. Appl. Therm. Enginee. 108, 388–397. DOI: 10.1016/j.applthermaleng.2016.07.118. 32. Shenoy, U.V. (1995). Heat Exchange Network Synthesis: Process Optimization by Energy and Resource Analysis . Gulf Publ. Co., Houston, TX. 33. Linnhoff, B. (1993

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The influence of the chain length and the functional group steric accessibility of thiols on the phase transfer efficiency of gold nanoparticles from water to toluene

Abstract

This paper describes the influence of the chain length and the functional group steric accessibility of thiols modifiers on the phase transfer process efficiency of water synthesized gold nanoparticles (AuNPs) to toluene. The following thiols were tested: 1-decanethiol, 1,1-dimethyldecanethiol, 1-dodecanethiol, 1-tetradecanethiol and 1-oktadecanethiol. Nanoparticles (NPs) synthesized in water were precisely characterized before the phase transfer process using Atomic Force Microscopy (AFM) and Transmission Electron Microscopy (TEM). The optical properties of AuNPs before and after the phase transfer were studied by the UV-Vis spectroscopy. Additionally, the particle size and size distribution before and after the phase transfer of nanoparticles were investigated using Dynamic Light Scattering (DLS). It turned out that the modification of NPs surface was not effective in the case of 1,1-dimethyldecanethiol, probably because of the difficult steric accessibility of the thiol functional group to NPs surface. Consequently, the effective phase transfer of AuNPs from water to toluene did not occur. In toluene the most stable were nanoparticles modified with 1-decanethiol, 1-dodecanethiol and 1-tetradecanethiol.

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Synthesis, characterization of Hollandite Ag2Mn8O16 on TiO2 nanotubes and their photocatalytic properties for Rhodamine B degradation

, J. & Wang, P. (2013). Preparation and characterization of palladium nano-crystallite decorated TiO 2 nano-tubes photoelectrode and its enhanced photocatalytic efficiency for degradation of Diclofenac. J. Hazard. Mater. 254, 141–148. DOI: 10.1016/j.jhazmat.2013.03.062. 6. Yu, X., Zhang, Y. & Cheng, X. (2014). Preparation and photoelectrochemical performance of expanded graphite/TiO 2 composite. Electrochim. Acta . 137, 668–675. DOI: 10.1016/j.electacta.2014.06.027. 7. Zhong, H., Shaogui, Y., Yongming, J. & Cheng, S. (2009). Microwave photocatalytic

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Adsorption Efficiency of Pentafl Uorobenzene on Ionic Liquids-Based Silicas

Abstract

The adsorption of pentafl uorobenzene on nine ionic liquid-based silicas was investigated using solid phase extraction. The effects of several variables such as the type of ionic liquid groups, adsorption time, temperatures and water ratio in the solution system were experimentally evaluated. The imidazole-chloride ionic liquid group based silica exhibited the highest adsorption effi ciency under the optimized conditions of 5 min adsorption at 30oC in water/methanol (30:70, vol%) solution. In addition, the effects of pH, as well as type and concentrations of chloride salts were investigated. At pH values other than neutral and high salt concentration, the adsorption effi ciency was reduced. Finally, the relative standard deviation of less than 5.8% over a 5-day period showed a high precision for the nine tested sorbents.

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Flocculation efficiency of hybrid polymers with trivalent metal cations

Abstract

Acrylamide/acrylic acid copolymers (AAm/AA) have been synthesized by microemulsion polymerization in absence and presence of trivalent cations Al+3 and Fe+3. Starch materials were obtained by introducing cations Al+3 and Fe+3, in the form of aqueous solutions of sulphates(VI) (modif. starch/Me+3), into the oxidized starch (modif. starch). The flocculation performance of obtained polyacrylamide copolymers and the one based on the natural polymer was compared with the performance of the commercial AAm/AA flocculant (CF). All materials were characterized by capillary viscometry, FTIR and DSC methods. An aqueous suspension of talc was used for the flocculation studies. The flocculation effectiveness was evaluated on the basis of reduction of suspension extinction and the sludge volume. It was found that synthesized AAm/AA/Me+3 copolymers and modif. starch/Me+3 materials exhibit better flocculation properties for a model talc suspension than a commercially available floculant.

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Structured catalytic reactor for VOC combustion

Structured catalytic reactor for VOC combustion

VOC emission has recently become a challenge for environmental protection. Catalytic combustion seems a promising method of VOC removal, however, there are still more specific demands concerning the process. The reactor design has to assure enhanced transfer properties accompanied by low flow resistance to reduce the pumping costs. Neither the packed beds nor the classic ceramic monoliths are able to fulfil the requirements.

To solve the problem we propose a wire gauze structure composed of several gauze sheets staked. A number of mass transfer and flow resistance experiments were performed for two gauze types and correlations were derived for the Sherwood number and the friction factor. The results were found to be in a reasonable agreement with the literature available.

The studied gauze structures were compared with a classic monolith for the assumed case study. The calculated length of the gauze structured reactor was significantly shorter, up to ten times, when compared with a classic ceramic monolith, but the pressure drop was higher.

Open access