Polycondensation reaction and its mechanism during lignocellulosic liquefaction by an acid catalyst: a review

The increase in the residue content resulting from polycondensation would be adverse to the utilization of lignocellulose and to the quality of products obtained from liquefied lignocellulosic material.The yield of the residue formed from liquefaction and the mechanism of polycondensation were reported mainly by Lin,Yamada and Kobayashi.The major products of cellulosic liquefaction are levulinic acid and hydroxymethylfurfural(HMF) derivatives under polyhydric alcohols and phenolated compounds under phenols.The cleavage of the β-O-4 bonds is the major reaction pathway of lignin liquefaction under various liquefying reagents regardless of whether they contain acid catalysts or not.The break up compounds by decomposition are polymerized to substances with high molecular weight by polycondensation in lignocellulosic liquefaction.The molecular weight of condensed residues increases almost linearly as a function of liquefaction time at the later stage of lignocellulosic liquefaction.The longer the time required,the greater the content of new residue generated by polycondensation during the entire process of liquefaction.We conclude that the condensed residues may stem from the interaction of degraded lignin and cellulose components in wood or from the products of two major components reacting with liquefying reagents.     

Stone, disc and hammer milling of bulgur

The effects on the milling quality of bulgur were compared using stone, disc and hammer mills. For each milling system bulgur particles were examined for appearance, surface structure, dimensions (max., min., mean, standard deviations and coefficient of variance), particle size distribution, bulk density and 1000 particle weight. Smooth and regular shaped bulgur particles were obtained using the abrasive stone and disc mills. Stone milled bulgur particles, were not split or glassy, but were opaque. Hammer milling significantly affected the appearance and surface characteristics of the bulgur particles and gave the lowest minimum dimensions and the highest deviation and variance in dimensions. The milling yields for hammer (98.3%) and stone (97.4%) mills were higher than for the disc mill (96.5%). Each mill gave a different distribution between coarse, medium and fine fractions. The highest yield of the coarse fraction (83.1%) was obtained using the stone mill. The results indicate that due to loss of quality, hammer milling is not suitable for bulgur preparation.     

Effects of olive oil mill wastewater used as irrigation water on in vitro pollen germination

The aim of this study is to assess the effects of Olive Oil Mill Wastewater (OOMW) application as irrigation water on in vitro pollen germination, focusing on total protein quantity. In test groups, pollen germination substances such as sucrose, H3BO3 and Ca(NO3)2 were added to different concentrations of OOMW and used as germination media. Regarding control group, the same substance melted into water instead of OOMW. As a result, in general, pollen germination percentage was decreased significantly in all OOMW concentrations than that of the control group, except 1/1000 concentrations. Similarly, total protein quantities declined linearly depending on decreasing OOMW concentrations, except 1/1 concentration which has 4-5 times the control value. Consequently, it was established that OOMW generally decreased pollen germination ratio and had carcinogenic effects on protein synthesis mechanism and must not be used as irrigation water without purification.     

Determining phenological and genetic variation in genotypes obtained from open-pollinated seeds of ‘Maraş 12’ walnut (Juglans regia L.) cultivar

Genetic Resources and Crop Evolution - In the present study, the phenological and genetic differences/similarities of 95 walnut genotypes were considered. These genotypes had been propagated...     

SODIUM CHLORIDE PRIMING IMPROVES SALINITY RESPONSE OF TOMATO AT SEEDLING STAGE

We aimed to investigate whether sodium chloride seed priming and irrigation at seedling stage enhance response of 5-leaf stage tomato plants (Lycopersium esculentum Mill.) to high salt stress. Three experimental groups were as; non-primed seeds, seeds primed with 0.05M sodium chloride (NaCl), and seeds primed and irrigated with 0.05M NaCl starting from sowing to salt stress application. Sodium chloride solutions (0.1M, 0.2M, 0.4M, and 0.6M) were added to cups under pots in every 2 days for 10 days to treatment groups. Control groups were irrigated with distilled water at the same time intervals. At least two experimental setups contained at least four plants, and two samplings of leaf and root tissues were performed for analysis of each plant to evaluate changes in pigment and proline contents, lipid peroxidation and electrolyte leakage levels, and ascorbate peroxidase and catalase activity. Priming reduced mean germination time, and increased final germination percentage together with energy of germination. Increased root and hypocotyl lengths as well as increases in fresh weights supported enhanced seedling vigor. Considering growth and stress parameters such as chlorophyll content, chlorophyll to carotenoid ratios, and lipid peroxidation and electrolyte leakage were less affected in primed plants. Moreover, improvement of the accumulation of osmoregulating defense molecules, such as proline and anthocyanin, and of the inductions of the antioxidative enzyme system points out to higher adaptive response of these plants against deleterious effects of salt.     

EFFECTS OF FOLIAR AND SOIL APPLICATIONS OF DIFFERENT MANGANESE FERTILIZERS ON YIELD AND NET RETURN OF BEAN

This study was carried out in order to determine the effect of various manganese fertilizers [manganese sulfate (MnSO₄.3H₂O) (MS), 27% manganese (Mn) and manganese ethylenediaminetetraacetic acid (Mn-EDTA) (ME), 12% Mn], their doses (0, 6, 9, 12 mg Mn kg^?1 for the soil and 0, 0.2, 0.3, 0.4% for the leaf) on yield and net return of dwarf bean. Field experiments were conducted in the randomized blocks split plot design with four replications under Konya ecological conditions in Turkey. Soil applications were made on bands as a single application at sowing whereas foliar applications (FA) were made at two times. Results of the field experiments showed the highest bean yields were significantly obtained by the fertilizer of ME-FA sprayed (243.80 and 257.74 kg da^?1). For both years, the lowest yields were obtained by the MS-SA applications (166.97 and 180.60 kg da^?1). The maximum net income was US $104.16 da^?1 and US $156.06 da^?1 by years.     

Biosorption of Methylene Blue from Aqueous Solutions by Hazelnut Shells: Equilibrium, Parameters and Isotherms

This paper presents a study on the batch adsorption of a basic dye, methylene blue (MB), from aqueous solution onto ground hazelnut shell in order to explore its potential use as a low-cost adsorbent for wastewater dye removal. A contact time of 24 h was required to reach equilibrium. Batch adsorption studies were carried out by varying initial dye concentration, initial pH value (3–9), ionic strength (0.0–0.1 mol L^?1), particle size (0–200 μm) and temperature (25–55°C). The extent of the MB removal increased with increasing in the solution pH, ionic strength and temperature but decreased with increase in the particle size. The equilibrium data were analysed using the Langmuir and Freundlich isotherms. The characteristic parameters for each isotherm were determined. By considering the experimental results and adsorption models applied in this study, it can be concluded that equilibrium data were represented well by Langmuir isotherm equation. The maximum adsorption capacities for MB were 2.14?×?10^?4, 2.17?×?10^?4, 2.20?×?10^?4 and 2.31?×?10^?4 mol g^?1 at temperature of 25, 35, 45 and 55°C, respectively. Adsorption heat revealed that the adsorption of MB is endothermic in nature. The results indicated that the MB strongly interacts with the hazelnut shell powder.     

Quantitation of fatty acids, sterols, and tocopherols in turpentine (Pistacia terebinthus Chia) growing wild in Turkey

The chemical composition (fatty acids, tocopherols, and sterols) of the oil from 14 samples of turpentine (Pistacia terebinthus L.) fruits is presented in this study. The oil content of the samples varied in a relatively small range between 38.4 g/100 g and 45.1 g/100 g. The dominating fatty acid of the oil is oleic acid, which accounted for 43.0 to 51.3% of the total fatty acids. The total content of vitamin E active compounds in the oils ranged between 396.8 and 517.7 mg/kg. The predominant isomers were alpha- and gamma-tocopherol, with approximate equal amounts between about 110 and 150 mg/kg. The seed oil of P. terebinthus also contained different tocotrienols, with gamma-tocotrienol as the dominate compound of this group, which amounted to between 79 and 114 mg/kg. The total content of sterols of the oils was determined to be between 1341.3 and 1802.5 mg/kg, with beta-sitosterol as the predominent sterol that accounted for more than 80% of the total amount of sterols. Other sterols in noteworthy amounts were campesterol, Delta5-avenasterol, and stigmasterol, which came to about 3-5% of the total sterols.     

Understanding Constraints and Facilitators to Salmon Angling Participation: Insights from Structural Equation Modeling

Atlantic salmon sport fisheries have declined remarkably in many countries and participation seems to correlate with salmon abundance. We investigated angling participation in the Atlantic salmon sport fishery in Norwegian rivers by incorporating facilitators for participation in a constraint–negotiation model. We conducted an Internet survey of Norwegian anglers yielding 3,635 responses (40% response rate). The structural model confirmed our hypotheses and supported the conceptual constraints-effects-mitigation model of leisure constraint negotiation. Of the constraints and facilitators investigated, the structural constraints and facilitators subcategory “quality of fishing” exerted the largest influence on angling participation. The influence of constraints and facilitators was mitigated by use of corresponding negotiation strategies where “skills, knowledge, and money,” and different substitution strategies were important. To increase participation, we suggest increasing salmon abundance, offering longer fishing stretches per angler, and providing better information about where to book salmon angling.