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41.
Neven Voa Josip Leto Tomislav Karaija Nikola Bilandija Anamarija Peter Hrvoje Kutnjak Jona uri Milan Poljak 《Molecules (Basel, Switzerland)》2021,26(14)
The application of municipal sewage sludge as fertilizer in the production of non-food energy crops is an environmentally and economically sustainable approach to sewage sludge management. In addition, the application of municipal sewage sludge to energy crops such as Miscanthus x giganteus is an alternative form of recycling nutrients and organic material from waste. Municipal sewage sludge is a potential source of heavy metals in the soil, some of which can be removed by growing energy crops that are also remediation agents. Therefore, the objective of the research was to investigate the effect of municipal sewage sludge applied at three different rates of 1.66, 3.22 and 6.44 t/ha on the production of Miscanthus. Based on the analyses conducted on the biomass of Miscanthus fertilized with sludge from the wastewater treatment plant in three fertilization treatments, it can be concluded that the biomass of Miscanthus is a good feedstock for the process of direct combustion. Moreover, the application of the largest amount of municipal sewage sludge during cultivation had no negative effect on the properties of Miscanthus biomass. Moreover, the cellulose and hemicellulose content of Miscanthus is ideal for the production of second-generation liquid biofuels. Fertilizer treatments had no effect on the content of cellulose and lignin, while a significant statistical difference was found for hemicellulose. 相似文献
42.
Visible and NIR luminescence of nanocrystalline β-Ga2O3:Er prepared by solution combustion synthesis
In this paper we report on facile solution combustion synthesis of erbium doped β-Ga2O3 with urea as fuel. The product was characterized using powder X-ray diffraction and transmission electron microscopy (TEM). X-ray diffraction and TEM showed that the material is nanostructured. Luminescence properties of β-Ga2O3:Er are studied with excitation in near infrared (Nd:YAG laser at 1064 nm) and visible (argon laser at 514.5 nm). A strong NIR emission of Er3+ in the window of minimal optical loss in silica based optical fibers, due to the 4I13/2→4I15/2 transition at 1.55 μm has been observed. Codoping with Yb3+ significantly increases the intensity of that important emission. 相似文献
43.
Vrankić Ilko Herceg Tomislav Pejić Bach Mirjana 《Central European Journal of Operations Research》2021,29(3):1001-1019
Central European Journal of Operations Research - In this paper, we analyse the company behaviour in duopoly taking into account the most common strategies, including dominant, reactive,... 相似文献
44.
Leading terms of relations for standard modules of the affine Lie algebras $$C_{n}^{(1)}$$ C n ( 1 )
The Ramanujan Journal - In this paper, we give a combinatorial parametrization of leading terms of defining relations for the vacuum level k standard modules for the affine Lie algebra of type... 相似文献
45.
Friscić T Fábián L Burley JC Reid DG Duer MJ Jones W 《Chemical communications (Cambridge, England)》2008,(14):1644-1646
Comparison of structure and hydration stability of pairs of chiral and racemic binary cocrystals indicates that the racemic solid is more stable than the chiral one; we illustrate that this difference might arise from intermolecular (crystal packing) factors in one case, while intramolecular (molecular conformation) factors are more significant in the other. 相似文献
46.
Tomislav P. Živković 《Journal of mathematical chemistry》2008,43(2):518-600
Interaction of a finite quantum system that contains ρ eigenvalues and eigenstates with an infinite quantum system that contains a single one-parameter eigenvalue band is considered. A new approach for the treatment of the combined system
is developed. This system contains embedded eigenstates with continuous eigenvalues , and, in addition, it may contain isolated eigenstates with discrete eigenvalues . Two ρ × ρ eigenvalue equations, a generic eigenvalue equation and a fractional shift eigenvalue equation are derived. It is shown that all properties of the system that interacts with the system can be expressed in terms of the solutions to those two equations. The suggested method produces correct results, however
strong the interaction between quantum systems and . In the case of the weak interaction this method reproduces results that are usually obtained within the formalism of the
perturbation expansion approach. However, if the interaction is strong one may encounter new phenomena with much more complex
behavior. This is also the region where standard perturbation expansion fails. The method is illustrated with an example of
a two-dimensional system that interacts with the infinite system that contains a single one-parameter eigenvalue band. It is shown that all relevant completeness relations are satisfied,
however strong the interaction between those two systems. This provides a strong verification of the suggested method. 相似文献
47.
We demonstrate the supramolecular and structural equivalence of two halogen-bond donors (I and Br) and three acceptors (O, NH and S) through the synthesis of seven isostructural halogen-bonded cocrystals, involving six different molecules: 1,4-dibromo- and 1,4-diiodotetrafluorobenzene (donors) and thiomorpholine, thioxane, morpholine, and piperazine (acceptors). The formation of isostructural cocrystals indicates how cocrystallization may be used to overcome shape and functional group dissimilarities that control molecular arrangement in the solid state. The differences in composition between the seven isostructural cocrystals directly affect the strength and nature of halogen bonds between their constituents, allowing the systematic variation of cocrystal physical properties, in particular the melting point, without affecting their crystal structure. Replacement of each O or S halogen-bond acceptor with an NH group provided an approximate 70 degrees C increase in melting point, whereas the replacement of I with Br as the halogen-bond donor lowered the melting point of the resulting solid by a similar amount. 相似文献
48.
An asymmetric intermolecular Stetter reaction of glyoxamide and alkylidenemalonates has been developed. Catalyzed by a novel N-heterocyclic carbene, the Stetter adducts are formed in good yield and excellent enantioselectivity. The presence of a sensitive epimerizable stereocenter is tolerated under these mildly basic reaction conditions if a bulky amine base is used. The products may be further elaborated to provide synthetically useful intermediates. 相似文献
49.
50.