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Biomass has been highlighted as an increasingly important renewable alternative energy source. Nonrenewable conventional energy sources covering global energy demands are processed to form solid, liquid, and gaseous hydrocarbons. Their environmental impact has led to the exploration of different types of biomasses for their potential to be used as raw materials. The present work reviews thermochemical processes, including pyrolysis, gasification, liquefaction, and torrefaction, on the conversion of biomass and plastic waste to gas, liquid, and solid fuels and chemicals. Upgrading some of the characteristics of bio-oil with various technologies has increased the interest in commercializing the usage of biomass in applications. In addition, biological conversion of biomass using second-generation feedstock instead of first-generation feedstock has decreased the cost and competition with food crops. The pretreatment of biomass using physical, chemical, physicochemical, and biological technologies is a typical process before biological conversion. Moreover, this work discusses biofuel production using syngas as feedstock through the Fischer–Tropsch process and organic acids as a feedstock for oleaginous microorganisms, including many species of yeast, bacteria, and algae.

Virgin linear low-density polyethylene was subjected to pyrolysis in a fluidized bed reactor pilot plant segmented into three heating zones with both sand and Magnofil BT 80 catalyst as bed materials. The pyrolysis oil and wax products were extracted at an average bed temperature of 600 and 700 °C. The oil yield decreased between 600 (8.7 wt %) and 700 °C (8.1 wt %) in an inverse relationship with the reaction time (358 and 384 min, respectively). This was attributed to an increase in the vibration of the polyolefin polymer matrix as a result of the absorbed thermal energy with an increase in temperature. The experiments performed at 700 °C showed no wax formation but high yields of gaseous products and oils, which are more lucrative in managing accumulated plastic waste, of which polyethylene constitutes large proportions, via thermochemical conversion technologies. The estimated calorific value at 600 °C was 45.5 MJ kg–1, which is in the acceptable range for both diesel and gasoline fuel market specifications. The sulfur content in the pyrolysis oil was estimated to be 0.013% and was not affected by changes in the temperature of the fluidized reactor. However, desulfurization will be required in the future to obtain oil within acceptable ranges of clean fuels. In addition, to support this work’s results in obtaining fuels from such feedstock materials, the fuel range hydrocarbons were also analyzed. The diesel fuel hydrocarbon range (C10–C19) was between 37 and 60% in the pyrolysis oils examined. The results determined experimentally from the pilot-plant work herein are quite promising for sustainable fuel integration plans in the near future with existing petroleum refining complexes.

This paper focuses on the earthquake performance of St. Konstantinos church that was damaged during 1995 Kozani earthquake. The structural elements that suffered the most damage were the main longitudinal exterior masonry walls, which included a considerable number of door and window openings. Initially, a numerical study is performed to determine the stiffness properties of representative simple masonry wall arrangements that included combination of openings. Based on the findings of this preliminary study, a three-dimensional (3-D) numerical simulation of the St. Konstantinos church was built. An analysis of the seismic response was next performed where the masonry walls were represented by linear “beam type” frame elements. The recordings of the ground acceleration that were obtained during the earthquake at a close distance from the church were utilized. The deformation levels obtained from this 3-D seismic analysis are used next, to approximate the earthquake performance of masonry walls through a more refined two-dimensional (2-D) FEM representation. These linear simulation results are utilized to predict the development of flexural or shear limit-state conditions for the exterior masonry walls. It was verified that the observed damages are in agreement with such predictions. The 2-D numerical investigation was extended to include a non-linear simulation of the observed behaviour utilizing either a Mohr–Coulomb or a modified von Mises failure envelope. Again, the observed damage of the masonry wall was approximated reasonably well by these non-linear numerical predictions. A retrofitting scheme which included the construction of internal reinforced concrete jacketing was also briefly presented and its beneficial result in the structural performance was verified.

Hydrogen is a clean and efficient energy carrier, and a hydrogen-based economy is an alternative solution for sustainability. The present work reviews the recent progress for hydrogen's production from various technologies including the generation from fossil fuels, from biomass through biological and thermochemical processes and from water splitting. Although hydrogen is a zero-emission energy when it is used, its cleanness depends on the production pathway that preceded. Hydrogen's storage and transportation has been costly and an unsafe procedure; formic acid (FA; CH2O2), on the other hand, can be generated, transported, and decomposed easily to hydrogen. Formic acid is generated from the hydrogenation of atmospheric carbon dioxide (CO2) and can easily be provided with energy portable devices, vehicles, and other applications. In addition, the most widely known homogeneous and heterogeneous catalysts and reactors for the formic acid reaction are presented. Different types of reactors like, fixed-bed reactors (FBRs), batch reactors, continuously stirred tank reactors (CSTRs) and microreactors were assessed for their performance and reaction's efficiency during formic acid’s decomposition.

ABSTRACTObjective:A sub-population analysis of 325 patients with agitation (Positive and Negative Syndrome Scale Excited Component [PEC] score ≥ 15 and ≤ 32; score of ≥ 4 on ≥ 2 items) associated with schizophrenia in a randomized, double-blind study investigating the efficacy and tolerability of intramuscular (IM) aripiprazole 9.75 mg, IM haloperidol 6.5 mg, or IM placebo and the transition to oral therapy.Research design and methods:Over 24 h, patients could receive up to three IM injections; the second and third administered ≥ 2 and ≥ 4 h, respectively, after the first, if deemed clinically necessary. Following IM treatment, oral aripiprazole or haloperidol was administered for 4 days. The primary efficacy measure was the mean change in PEC score from baseline at 2 h.Results:At 2 h, mean improvements in PEC scores with IM aripiprazole (–8.0) were significantly greater versus IM placebo (–5.7; p≤ 0.01), and similar versus IM haloperidol (–8.3). Secondary efficacy measures also significantly improved with active IM treatment versus IM placebo. Continuation with oral treatment provided continued efficacy with both active treatments. The safety profiles of IM and oral aripiprazole were similar. The incidence of extrapyramidal symptom-related adverse events was 0% with IM aripiprazole, 1.6% with IM placebo and 16.5% with IM haloperidol.Conclusion:Intramuscular aripiprazole is effective in patients with acute agitation associated with schizophrenia, comparable to IM haloperidol, and enables convenient transfer to oral aripiprazole therapy.

The chiral rhodium complex pentamethylcyclopentadienylrhodium chloride dimer combined with the ligand 1R,2S-aminoindanol provides a superior catalyst for the rapid, high-yielding asymmetric transfer hydrogenation of acetophenone with 2-propanol to produce (R)- and (S)-(1)-phenylethanol. The effects of various reaction parameters such as reaction temperature, catalyst and substrate concentration, gaseous environment, and acetone concentration on conversion and enantioselectivity were investigated. The results indicate that catalyst can be deactivated by high temperature and air atmosphere, acetone reduces the reaction rate, and enantioselectivity decreases with conversion.

The coking of an ultrastable Y zeolite was investigated during cracking of n-octane, isooctane, and 1-octene in a fixed-bed reactor over a temperature range of 523−623 K, various residence times, and various reactant compositions. The coking tendencies were found to be in the following descending order:  1-octene > isooctane > n-octane. In all cases, the coke content increased with increasing reactant feed composition or residence time. However, the coke amount formed was not proportional to the reactant feed composition, because of a strong pseudo-zeroth-order initial coking on strong acidic sites. Coke formation during the first minute of TOS was significantly faster than at later stages, because of the very strong zeolitic acid sites, which deactivated rapidly. Differences in coke formation at different compositions started to build only later at much lower rates. Similarly, coke content increased with increasing reaction temperature at high compositions. However, at low reactant compositions, the coke content decreased with increasing temperature for isooctane and 1-octene. This was due to an increase in desorption of the olefin intermediates responsible for coke formation into the gas phase with increasing temperature.

Nickel‐loaded HEU‐type zeolite crystals have been obtained by well‐known synthetic procedures and characterised by X‐ray fluorescence (XRF), scanning‐electron microscopy/energy‐dispersive spectroscopy (SEM‐EDS), FT‐IR, diffuse reflectance UV/Vis spectroscopy (DR(UV/Vis)S) and X‐ray photoelectron spectroscopy (XPS) measurements as non‐homoionic and non‐stoichiometric substances containing exchangeable hydrated Ni2+ions in the micropores and nickel hydroxide phases supported on the surface. Thermogravimetric analysis/ differential gravimetry (TGA/DTG) and differential thermal analysis (DTA) demonstrated that full dehydration below approximately 400 °C follows a clearly endothermic process, whereas at higher temperatures the zeolite is amorphised and finally partially recrystallised to Ni(Al,Si) oxides, detected by powder X‐ray powder diffraction (XRD). The solid acidity of NiHEU, initially determined by temperature‐programmed desorption (TPD) of ammonia to be 8.93 mg g−1NH3, is attributed to the weak acid sites (fundamentally Lewis sites) resolved at approximately 183 °C, and to the strong acid sites (essentially Brønsted sites) resolved at approximately 461 °C in the TPD pattern. A more sophisticated study based on in situ/ex situ FT‐IR with in situ/ex situ 27Al MAS NMR and pyridine (Py) as a probe molecule, revealed that the Lewis acid sites can be attributed primarily to Ni2+ions, whereas the Brønsted ones can probably be associated with the surface‐supported nickel hydroxide phases. The spectroscopic measurements in conjunction with powder XRD and 29Si MAS NMR data strongly suggest that distorted Al tetrahedra are formed during the dehydration process and Py chemisorption/complexation (NiHEU‐Py), whereas the crystal structure is remarkably well preserved in the rehydrated material (NiHEU‐Py/R). The structural, electronic, energetic and spectroscopic properties of all possible nickel(II) aqua and dihydroxy complexes absorbed in the zeolite micropores or supported on the zeolite surface were studied theoretically by density functional theory (DFT). The computed proton affinity, found to be in the range 182.0–210.0 kcal mol−1, increases with increasing coordination number of the aqua and dihydroxy nickel(II) complexes.

The catalytic cracking of polyethylene has been studied over two natural clays and their pillared analogues with a view toward assessing their suitability in a process for recycling plastic waste to fuel. Although these clays were found to be less active than US-Y zeolite around 600 K, at slightly higher process temperatures, they were able to completely decompose polyethylene. Their yields to liquid products were around 70%, compared to less than 50% over US-Y zeolite. Moreover, the liquid products obtained over the clay catalysts were heavier. Both of these facts are attributed to the milder acidity of clays, as the very strong acidity characterizing zeolites leads to overcracking. Furthermore, this milder acidity leads to significantly lower occurrence of hydrogen-transfer secondary reactions compared to US-Y zeolite, and as a consequence, predominantly alkenes were the products over the clay catalysts. An additional advantage of these catalysts is the considerably lower amount of coke formed.

The catalytic degradation of high-density polyethylene (hdPE) over ultrastable Y zeolite in a semibatch reactor was studied at different heating rates and reaction temperatures. Catalytic degradation of the polymer occurred at much lower temperatures than pure thermal degradation. When gel permeation chromatography was used to determine the molar mass distribution, it was found that solid state reactions occur only in the presence of a catalyst. These reactions change the polymer structure well before the formation of significant amounts of volatile products. The pattern of formation of gaseous and liquid products was studied and found to follow the temperature increase. After the system reached its final temperature, the reaction rate of formation of volatile products decreased rapidly. The product range was typically between C3 and C15. Isobutane and isopentane were the main gaseous products. The liquid product fraction was alkane-rich, as alkenes rapidly undergo bimolecular hydrogen transfer reactions to give alkanes as secondary products.

The catalytic degradation of high-density polyethylene to hydrocarbons was studied over different zeolites. The product range was typically between C3 and C15 hydrocarbons. Distinctive patterns of product distribution were found with different zeolitic structures. Over large-pore ultrastable Y, Y, and β zeolites, alkanes were the main products with less alkenes and aromatics and only very small amounts of cycloalkanes and cycloalkenes. Medium-pore mordenite and ZSM-5 gave significantly more olefins. In the medium-pore zeolites secondary bimolecular reactions were sterically hindered, resulting in higher amounts of alkenes as primary products. The hydrocarbons formed with medium-pore zeolites were lighter than those formed with large-pore zeolites. The following order was found regarding the carbon number distribution:  (lighter products) ZSM-5 < mordenite < β < Y < US-Y (heavier products). A similar order was found regarding the bond saturation:  (more alkenes) ZSM-5 < mordenite < β < Y < US-Y (more alkanes). Dependent upon the chosen zeolite, a variety of products was obtained with high values as fuel, confirming catalytic degradation of polymers as a promising method of waste plastic recycling.

A computer algorithm was developed to perform replenishment and reuse of the drain nutrient solution in close hydroponic systems on the basis of dispensing as many nutrients and water in it as were needed to maintain a target electrical conductivity in the irrigation solution. To achieve this in each watering application, dilution ratios of the concentrated fertilizer solutions are automatically adjusted through a computer program based on this algorithm, in relation to the volume and the electrical conductivity of the drain solution. It was proved that the returning nutrient solution could be corrected and reused efficiently through this method. However, the concentration of P, Mn and Zn in the irrigation nutrient solution was extremely low in samples taken after continual reuse of the drain solution for a fortnight. Since the analysed irrigation solution was prepared using a large quantity of drain solution, it seems likely that reduced P, Zn and Mn concentrations in the former were due to the high pH of the latter, and this may have caused immobilization of these elements.

Natural zeolitic material composed of natrolite and thomsonite intergrowths (NAT/THO) was treated in solutions of different initial pH values at 25°C under N2 atmosphere and in 1M KCl as ionic modulator, until pH equilibration. The solid experimental products were studied by means of powder X-ray diffraction (XRD), scanning electron microscopy-energy dispersive system (SEM-EDS), Fourier-transformed infra-red (FTIR) and thermogravimetric analysis/differential thermal analysis (TGA/DTA). The liquid experimental products were analysed using atomic absorption spectroscopy (AAS) and atomic emission spectroscopy (AES). The NAT/THO material exhibited an amphoteric character with a tendency to neutralise the reacting solutions. The pH equilibration was faster for the acidic region than for the basic one. The H+ ions are chemisorbed on the bulk material, whereas the OH− ions promote a proton detachment from the exchangable cation-water complexes. No Brœnsted acidity, possibly responsible for the neutralisation in the basic region, was found by temperature-programmed desorption (TPD) measurements. Reaction mechanisms involving hydrolysis and degradation-dissolution are proposed. Zeolite crystals remaining at the end of the experiments showed no loss of crystallinity, phase transformation nor even framework dealumination. The insertion of K+ into the zeolites is suggested here as the reason as to why no collapse of their crystal structure occurred in the most acidic solutions causing the zeolites to be more resistant to chemical weathering.

The loss of pendimethalin (N-(ethylpropyl)-2,6-dinitro-3,4-xylidine), a selective herbicide in runoff water was determined on sandy-clay-loam soil plots cultivated with tobacco in relation with the use of ammonium nitrate limestone as fertelizer, for a period of two years, 1990 and 1991. The surface slope of plots was 11% and the use of fertilizer decreased the soil erosion from a value 617 g/m2to 320 g/m2. The runoff of surface waters were between 16-24% of the rainfall amounts. Reduction in pendimethalin in waterways results from water loss by infiltration, sediment loss, and by attachment adsorption on vegetative and organic matter. Surface runoff levels were highest for the first runoff event after herbicide application, 1.5 g/10 m2 and initial concentrations were related to the time lapse between herbicide application and the date of the first run-off event. Maximum concentrations were 5.95 and 8.54 μg/L in 1990 and 1991 respectively. Persistence studies showed that pendimethalin concentration in runoff of 0.5 cm soil layer decreased by 88.2%, from 2.46 to 0.29 μg/g within 233 days, in 1990 and by 87.6%, from 2.42 to 0.30 μg/g within 235 days in 1991. After 310 day the concentration of pendimethalin was only 0.1 μg/g.