Incorporating uncertainty in data driven regression models of fluidized bed gasification: A Bayesian approach

In recent years, different non-linear regression techniques using neural networks and genetic programming have been applied for data-driven modelling of fluidized bed gasification processes. However, none of these methods explicitly take into account the uncertainty of the measurements and predictions. In this paper, a Bayesian approach based on Gaussian processes is used to address this issue. This method is used to predict the syngas yield production and the lower heating value (LHV) for municipal solid waste (MSW) gasification in a fluidized bed gasifier. The model parameters are calculated using the maximum a-posteriori (MAP) estimate and compared with the Markov Chain Monte Carlo (MCMC) method. The simulations demonstrate that the Bayesian methodology is a powerful technique for handling the uncertainties in the model and making probabilistic predictions based on experimental data. The method is generic in nature and can be extended to other types of fuels as well

Poultry Litter Gasification in a Fluidized Bed Reactor: Effects of Gasifying Agent and Limestone Addition

Air and air-steam gasification of poultry litter was experimentally studied in a laboratory scale bubbling fluidized bed gasifier at atmospheric pressure using silica sand as the bed material. The effects of equivalence ratio (ER), gasifier temperature, steam-to-biomass ratio (SBR), and addition of limestone blended with the poultry litter, on product gas species yields and process efficiency, are discussed. The optimum conditions (maximum carbon conversion, gas yield, heating value, and cold gas efficiency) were achieved at an ER 0.25 and 800 °C, using air (SBR = 0) and poultry litter blended with 8% w/w limestone, yielding a product gas with a lower heating value (LHV) of 4.52 MJ/Nm 3 and an average product gas composition (dry basis) of H 2 : 10.78%, CO: 9.38%, CH 4 : 2.61, and CO 2 : 13.13. Under these optimum processing conditions, the cold gas efficiency, carbon conversion efficiency, and hydrogen conversion efficiency were 89, 73, and 43% respectively. The reported NH 3 measurement at an ER of 0.28 and 750 °C is 2.7% (equivalent to 19,300 mg/Nm 3 ) with 14.7 mg/Nm 3 of HCl observed as the dry product gas. High temperature and steam injection favor production of CO and H 2 , while their effect on CH 4 was almost negligible. It is demonstrated that poultry litter can be gasified by blending with limestone, making it possible to overcome the fluidization problems caused by the mineral composition of poultry litter ash (high K and P content), yielding a gas with a similar heating value compared to gasifying without limestone addition, but with a significantly lower tar content

Nickel and copper complexes based on tridentate nitrogen donor ligand 2,6-bis-(1-phenyliminoethyl) pyridine: synthesis, spectral and structural characterization

The reaction of CuCl₂•2H₂O with 2,6-bis(1-phenyliminoethyl)pyridine (referred hereafter as L) in 1:1 molar ratio in methanol or acetronitrile at room temperature afforded distorted trigonal-bipyramidal complex [Cu(κ³-L)Cl₂]. On the other hand, the reaction of NiCl₂•6H₂O with 2 equivalents of L gave an octahedral complex [Ni(κ³-L)₂]²⁺, which was isolated as [Ni(κ³-L)₂][BF₄]₂ using NH₄BF₄. The complexes have been characterized by elemental analyses, FAB-MS, IR, EPR and electronic spectral studies. Molecular structures of both the [Cu(κ³-L)Cl₂] (1) and [Ni(κ³-L)₂](BF₄)₂ (2) have been determined by single crystal X-ray analyses. Weak interaction studies on 1 and 2 revealed stabilisation of the crystal packing by inter and intra-molecular C–H⋯X (X=F, Cl, π) interactions. In complex 2 ortho C–H bond from phenyl rings leads to unexpected C–H⋯π interaction with nickel α,α′-diimine chelate ring. This provides structural support for metalloaromaticity in the chelate ring of complex 2

Ru(II) complexes imparting N<SUB>2</SUB>O<SUB>2</SUB> donor bis chelating ligand N,N′-bis(salicylidine)-hydrazine in unusual coordination mode

The synthesis and characterization of binuclear ruthenium complexes [{(η⁶-C₆H₆)Ru}₂(μ-bsh)₂](1), [{(η⁶-C₁₀H₁₄)Ru}₂(μ-bsh)₂] (2), [{(η⁶-C₆Me₆)Ru}₂(μ-bsh)₂] (3), and rhodium complex [{(η⁵-C₅Me₅)RhCl}₂(μ-bsh)] (4) (bsh=N,N^′-bis(salicylidine)-hydrazine dianion) are reported. The complexes have been fully characterized by analytical and spectral techniques and unusual coordination mode of the ligand H₂bsh has been confirmed by single crystal X-ray analysis of the complex 2. Structural data revealed extensive inter- and intra-molecular C–H⋯O and C–H⋯π interactions and involvement of methyl and isopropyl hydrogen from the p-cymene in hydrogen bonding

Ruthenium(II) polypyridyl complexes: potential precursors, metalloligands, and topo II inhibitors

Neutral and cationic mononuclear complexes containing both group 15 and polypyridyl ligands [Ru(κ³-tptz)(PPh₃)Cl₂] [1; tptz = 2,4,6-tris(2-pyridyl)-1,3,5-triazine], [Ru(κ³-tptz)(κ²-dppm)Cl]BF₄ [2; dppm = bis(diphenylphosphino)methane], [Ru(κ³-tptz)(PPh₃)(pa)]Cl (3; pa = phenylalanine), [Ru(κ³-tptz)(PPh₃)(dtc)]Cl (4; dtc = diethyldithiocarbamate), [Ru(κ³-tptz)(PPh₃)(SCN)₂] (5) and [Ru(κ³-tptz)(PPh₃)(N₃)₂] (6) have been synthesized. Complex 1 has been used as a metalloligand in the synthesis of homo- and heterodinuclear complexes [Cl₂(PPh₃)Ru(μ-tptz)Ru(η⁶-C₆H₆)Cl]BF₄ (7), [Cl₂(PPh₃)Ru(μ-tptz)Ru(η⁶-C₁₀H₁₄)Cl]PF₆ (8), and [Cl₂(PPh₃)Ru(μ-tptz)Rh(η⁵-C₅Me₅)Cl]BF₄ (9). Complexes 7−9 present examples of homo- and heterodinuclear complexes in which a typical organometallic moiety [(η⁶-C₆H₆)RuCl]⁺, [(η⁶-C₁₀H₁₄)RuCl]⁺, or [(η⁵-C₅Me₅)RhCl]⁺ is bonded to a ruthenium(II) polypyridine moiety. The complexes have been fully characterized by elemental analyses, fast-atom-bombardment mass spectroscopy, NMR (¹H and ³¹P), and electronic spectral studies. Molecular structures of 1−3, 8, and 9 have been determined by single-crystal X-ray diffraction analyses. Complex 1 functions as a good precursor in the synthesis of other ruthenium(II) complexes and as a metalloligand. All of the complexes under study exhibit inhibitory effects on the Topoisomerase II−DNA activity of filarial parasite Setaria cervi and β-hematin/hemozoin formation in the presence of Plasmodium yoelii lysate

Tuned helical array of Rh<SUP>III</SUP>/Ir<SUP>III</SUP> Cp* complexes with polypyridyl ligands

Reactions of the chloro-bridged dimeric complexes [{(η⁵-C₅Me₅)M(μ-Cl)Cl}₂] (M = Rh, Ir) with the polypyridyl ligands 2,3-di(2-pyridyl)pyrazine (dpp) and 2,4,6-tri(2-pyridyl)-1,3,5-triazine (tptz) in the presence of ammonium tetrafluoroborate gave the mononuclear complexes [(η⁵-C₅Me₅)MCl(κ²-dpp)]BF₄ [M = Rh (1), Ir (2)] and [(η⁵-C₅Me₅)MCl(κ²-tptz)]BF₄ [M = Rh (3), Ir (4)]. The complexes have been characterised by elemental analysis, FAB-MS, ESMS, IR, NMR, electronic and emission spectroscopic studies and the molecular structures of 1, 2 and 3 have been crystallographically determined. Structural studies on the complexes revealed the presence of helical superstructures resulting from C–H•••X (X = N, F, Cl and π) interactions

Growth Potential of Red Hairy Caterpillar Amsacta moorei in Relation To Certain Food Plants

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Synthetic, spectral and structural studies of some homo and hetero binuclear arene ruthenium (II) polypyridyl complexes

Homo-hetero binuclear cationic complexes with the formulation [(η⁶-arene)RuCl(μ-dpp)(L)]⁺ (η⁶-arene=benzene; L=PdCl₂ (1a); PtCl₂ (1b), and η⁶-arene=p-cymene; L=PdCl₂ (2a); PtCl₂ (2b)), [(η⁶-arene)RuCl(μ-dpp)(L)]²⁺(η⁶-arene=p-cymene; L=[(η⁶-C₆H₆)RuCl] (2c), and [(η⁶-C₁₀H₁₄)RuCl] (2d)) were prepared. Molecular structure of the representative homo binuclear complex [{(η⁶-C₁₀H₁₄)RuCl}(μ-dpp){(η⁶-C₁₀H₁₄)RuCl}](PF₆)₂ (2d) was determined crystallographically. Weak interaction studies on the complex 2d revealed stabilisation of the crystal packing by weak inter and intra molecular C–H⋯X (X=F, Cl, π) and π–π interactions. The C–H⋯F interactions lead to parallel helical chains and encapsulation of counter anion in self-assembled cavity arising from C–H⋯π and π–π weak interactions