Simultaneous ammonium and phosphate recovery and stabilization from urban sewage sludge anaerobic digestates using reactive sorbents

The use of low-cost inorganic sorbents as a new sustainable strategy to enhance the valorization of nutrients (N-P-K), from the urban water cycle (e.g., side streams from sewage sludge anaerobic digestion), in agriculture applications is presented. The simultaneous recovery and stabilization of ammonium and phosphate by using a mixture of two reactive sorbents (Na and K zeolites and magnesium oxide) was evaluated. The nutrients stabilization process, favoured at alkaline pH values, is carried out by a) the precipitation of phosphate ions with magnesium and/or ammonium ions and b) the sorption of ammonium by Na- and K-zeolites. MgO(s) promoted the stabilization of phosphate as bobierrite (Mg3(PO4)2(s)) or struvite (MgNH4PO4(s)) depending on the applied dose. Doses with the stoichiometric molar ratio of Mg/P promote the formation of bobierrite, while molar ratios higher than 3 favour the formation of struvite. Na zeolites (NaP1-NA, NaP1-IQE) demonstrated efficiency on ammonium stabilization between 60 ± 2 (for 15 gZ/L) to 90 ± 3% (for 50 gZ/L). The ammonium recovery efficiency is limited by the zeolite sorption capacity. If the target of the fertilizing criteria should include K, then the use of a K-zeolite (e.g., 5AH-IQE) provides a good solution. The optimum pH for the precipitation of struvite and bobierrite is 9.5 and the optimum pH for ammonium removal is between 4 and 8.5. N is present in higher concentrations (up 0.7–1 g NH4+/L) when pH is ranged between 8.2 and 8.6. The ammonium recovery ratios were better than those previously reported using only magnesium oxide or even a more expensive reagent as newberrite (MgHPO4(s)). The recovery mechanisms described generate low-solubility stabilized nutrients forms that potentially can be applied as slow-release fertilizers in agriculture. Thus, the use in agriculture of blends of digested sludge with low-solubility stabilized nutrients forms will improve soils quality properties in terms of organic matter and nutrients availability.Peer ReviewedPostprint (author's final draft

Simultaneous ammonium and phosphate recovery and stabilization from urban sewage sludge anaerobic digestates using reactive sorbents

The use of low-cost inorganic sorbents as a new sustainable strategy to enhance the valorization of nutrients (N-P-K), from the urban water cycle (e.g., side streams from sewage sludge anaerobic digestion), in agriculture applications is presented. The simultaneous recovery and stabilization of ammonium and phosphate by using a mixture of two reactive sorbents (Na and K zeolites and magnesium oxide) was evaluated. The nutrients stabilization process, favoured at alkaline pH values, is carried out by a) the precipitation of phosphate ions with magnesium and/or ammonium ions and b) the sorption of ammonium by Na- and K-zeolites. MgO(s) promoted the stabilization of phosphate as bobierrite (Mg3(PO4)2(s)) or struvite (MgNH4PO4(s)) depending on the applied dose. Doses with the stoichiometric molar ratio of Mg/P promote the formation of bobierrite, while molar ratios higher than 3 favour the formation of struvite. Na zeolites (NaP1-NA, NaP1-IQE) demonstrated efficiency on ammonium stabilization between 60±2 (for 15gZ/L) to 90±3% (for 50gZ/L). The ammonium recovery efficiency is limited by the zeolite sorption capacity. If the target of the fertilizing criteria should include K, then the use of a K-zeolite (e.g., 5AH-IQE) provides a good solution. The optimum pH for the precipitation of struvite and bobierrite is 9.5 and the optimum pH for ammonium removal is between 4 and 8.5. N is present in higher concentrations (up 0.7-1gNH4+/L) when pH is ranged between 8.2 and 8.6. The ammonium recovery ratios were better than those previously reported using only magnesium oxide or even a more expensive reagent as newberrite (MgHPO4(s)). The recovery mechanisms described generate low-solubility stabilized nutrients forms that potentially can be applied as slow-release fertilizers in agriculture. Thus, the use in agriculture of blends of digested sludge with low-solubility stabilized nutrients forms will improve soils quality properties in terms of organic matter and nutrients availability

PHYSIOLOGICAL RESPONSE AND NUTRIENT RECOVERY OF COOL-SEASON TURFGRASSES UNDER VARIOUS ENVIRONMENTAL STRESSES

Potassium (K) is an essential plant nutrient commonly applied to increase creeping bentgrass tolerance to environmental stresses and maintain overall turfgrass stand health. Limited research defining the K requirement of creeping bentgrass under heat and drought stress exists. Furthermore, research investigating K, calcium (Ca), and magnesium (Mg) recovery under abiotic stress has been inconsistent. To build on previous research and investigate the differences between liquid and granular K fertilization, experiments were conducted to evaluate the performance of liquid and granular K carriers in conjunction with liquid calcium and magnesium on their ability to suppress summer bentgrass decline of creeping bentgrass (Agrostis stolonifera L.) grown in the transition zone of the United States. A field experiment was conducted from May 2006 to October 2007 to investigate liquid and granular K fertilization on turfgrass quality, clipping yield, chlorophyll, root weight, volumetric soil water content and leaf and root nutrient concentrations of \u27Crenshaw\u27 creeping bentgrass. Treatments consisted of two annual potassium rates, 0 and 195 kg K ha-1 yr-1, in liquid and granular forms, with either liquid calcium (49 kg ha-1 yr-1), liquid magnesium (49 kg ha-1 yr-1), or both. Liquid K applications significantly reduced visual quality of bentgrass during 2006. Turfgrass quality in 2007 was unacceptable (\u3c7) for the months of June, August, and September, while only plots receiving Ca without K produced acceptable turf. Clipping yield was also significantly decreased under liquid K in August and November 2006, while calcium produced the greatest yield in July and August 2006 and September and October 2007. \u27Crenshaw\u27 creeping bentgrass treated with liquid K produced 8 and 16% greater clipping K concentration in August and November 2006 and 11 and 21% greater tissue K content by June and October 2007 compared to untreated. Another two year field study was conducted from May 2006 to October 2007 to determine the performance of two K carriers (liquid and granular) under rates of 0, 98 and 195 kg ha-1 annually and a wetting agent (WA) at 19.09 L WA ha-1 monthly. Data concerning visual turf quality, clipping yield, root weight, soil moisture, soil hydrophobicity, and leaf and root tissue nutrient concentrations were recorded. Turf quality was improved by the high rate of granular K; however, quality significantly declined for turf receiving the higher liquid K rate throughout 2006 from phototoxic effects of foliar K fertilizers. Wetting agent decreased turf quality in 2006 partially due to excess soil water retention but creeping bentgrass quality was improved under drought conditions in 2007 with the addition of WA. In August and November 2006 and June and October 2007, liquid K at 195.29 kg ha-1 produced greater leaf tissue K concentrations compared to untreated. Liquid K at the 195.29 kg ha-1 rate adversely affected root weight in August 2006 and October 2007 by 36% and 20%, respectively, while yearly declines in root weight of all treatments were noted. Soil hydrophobicity decreased by 19.92 and 7.16 units at 1.5 cm in 2006 and 2007, respectively, and declined by 8.86 and 6.64 units at 3.0 cm in 2006 and 2007, respectively, with the addition of the WA. A third field study was conducted from November 2006 to February 2008 to examine the interactive effects of nitrogen (N) and iron (Fe) fertilization on rough bluegrass (Poa trivialis L.) overseed stands under reduced light environments. Treatments included three annual N rates of 49, 98, and 147 kg N ha-1 yr-1 split between 4 applications during the winter months. Fe was supplied simultaneously at 10.8 kg a.i. ha-1 per season. Shade treatments included full sunlight and 55% shade and were applied daily. Data collection included turf quality, clipping yield, chlorophyll, and clipping nutrient concentrations. In this experiment, turf quality was improved with increased N rate and shade treatments in year 1; however visual quality declined greatly for turf under reduced light irradiances and higher N rates by year 2. Rough bluegrass clipping yield and chlorophyll content generally increased linearly with increasing N rates; while shade increased clipping yield by 28% in December 2006 and reduced yield by 38 and 33% in December and February 2007, respectively. Leaf tissue N concentrations were greatest under the highest N rates until February of year 2 when the 98 kg K ha-1 yr-1 rate produced 16% greater tissue N concentration compared to the 147 kg K ha-1 yr-1 rate. Rough bluegrass treated with foliar applications of Fe generally exhibited minimal and inconsistent effects on leaf N, Fe and chlorophyll content compared to non-Fe treated turf

Basic Properties and Information Theory of Audic-Claverie Statistic for Analyzing cDNA Arrays

BACKGROUND: The Audic-Claverie method [1] has been and still continues to be a popular approach for detection of differentially expressed genes in the SAGE framework. The method is based on the assumption that under the null hypothesis tag counts of the same gene in two libraries come from the same but unknown Poisson distribution. The problem is that each SAGE library represents only a single measurement. We ask: Given that the tag count samples from SAGE libraries are extremely limited, how useful actually is the Audic-Claverie methodology? We rigorously analyze the A-C statistic that forms a backbone of the methodology and represents our knowledge of the underlying tag generating process based on one observation. RESULTS: We show that the A-C statistic and the underlying Poisson distribution of the tag counts share the same mode structure. Moreover, the K-L divergence from the true unknown Poisson distribution to the A-C statistic is minimized when the A-C statistic is conditioned on the mode of the Poisson distribution. Most importantly, the expectation of this K-L divergence never exceeds 1/2 bit. CONCLUSION: A rigorous underpinning of the Audic-Claverie methodology has been missing. Our results constitute a rigorous argument supporting the use of Audic-Claverie method even though the SAGE libraries represent very sparse samples

Assessment of Genetic Relationship among Male and Female Fig Genotypes Using Simple Sequence Repeat (SSR) Markers

Fig (Ficus carica L.) is a traditional crop in Turkey and widely cultivated around the Mediterranean areas. The gynodioecious fig species is present in two sexual forms, i.e. the domesticated fig (female tree) and the caprifig (male tree). Caprifigs are crucial for high quality fig production and breeding while, the studies on assessment of genetic relationship among caprifigs is limited. The aim of this study was to determine genetic diversity among 45 caprifigs and 2 female figs collected from four provinces in Marmara and Aegean Sea Regions of Turkey using simple sequence repeat (SSR) markers. In this work, 24 SSR markers were tested, one was monomorphic and the remaining markers amplified 82 alleles. The number of polymorphic alleles per SSR marker ranged from 2 to 7. The observed heterozygosity (Ho) differed from 0.18 to 0.76 and expected heterozygosity (He) ranged between 0.24 and 0.81. The polymorphism information content (PIC) varied from 0.42 to 0.98. A UPGMA analysis based on Dice similarity matrix clustered fig genotypes into two main groups and similarly, STRUCTURE analysis placed fig genotypes into two different gene pools (K=2). Fig genotypes collected from the same region were not clustered together in a group indicating that the fig genotypes did not cluster on the basis of their collection sites. Our results demonstrated that caprifigs and female figs are not genetically distinct and they clustered together in a group. All fig genotypes had distinct SSR marker profiles suggesting that there were no synonyms or homonyms. These results revealed a high genetic variation among fig genotypes and 23 SSR markers were enough to discriminate all fig genotypes analysed in this study demonstrating that SSR marker system is suitable for genetic analysis in figs

The fate of micronutrients in excreta of sheep supplemented with organic/inorganic micronutrients in a pasture system

Micronutrients play an important role in metabolic reactions in animals. To correct for potential micronutrient deficiencies in forages, the dominant feed source for ruminants, farmers routinely administer supplements to animals prophylactically. Micronutrients that are not absorbed from supplements are excreted, providing a potential flux of micronutrients to soil for uptake by forages. However, it is unclear if the form of supplemental minerals given to animals significantly affects the flux of micronutrients in pasture systems. This study investigated the impacts of supplement form (organic or inorganic), dose, excreta type (urine and/or faeces), and soil organic matter (OM) on the flux of micronutrients in a grazing pasture system. Over two weeks, 24 sheep were supplemented with organic or inorganic forms of Zn, Cu, Mn, and Se at two industrial doses. The excreta were applied to potted soils and seeded with perennial ryegrass (Lolium perenne L.). The redistribution of micronutrients was followed from feed to excreta to soil to grass. Over 90% of the Cu, Zn and Mn, and over 80% of the Se was excreted through faeces, regardless of supplement form or dose. The concentrations of bioavailable Zn, Cu, Mn and Se in faeces were not significantly affected by the supplement form, but recalcitrant fractions of Zn, Cu and Se were, implying a potential long-term effect of supplement form on micronutrient bioavailability in soils. Uptake of Zn, Cu and Mn by ryegrass was most affected by excreta type. Although faeces contributed 20-1200 times more Zn, Cu and Mn than urine, micronutrient uptake by ryegrass was significantly higher in soils applied with urine because N, K and S in urine increased grass growth. Uptake of Se by ryegrass was limited in high OM soils regardless of excreta type, revealing antagonism between the benefits of OM to plant growth and the bioavailability of Se

Ferrierite and Its Delaminated and Silica-Intercalated Forms Modified with Copper as Effective Catalysts for NH3-SCR Process

[EN] The main goal of the study was the development of effective catalysts for the low-temperature selective catalytic reduction of NO with ammonia (NH3-SCR), based on ferrierite (FER) and its delaminated (ITQ-6) and silica-intercalated (ITQ-36) forms modified with copper. The copper exchange zeolitic samples, with the intended framework Si/Al ratio of 30 and 50, were synthetized and characterized with respect to their chemical composition (ICP-OES), structure (XRD), texture (low-temperature N(2)adsorption), form and aggregation of deposited copper species (UV-vis-DRS), surface acidity (NH3-TPD) and reducibility (H-2-TPR). The samples of the Cu-ITQ-6 and Cu-ITQ-36 series were found to be significantly more active NH3-SCR catalysts compared to Cu-FER. The activity of these catalysts in low-temperature NH3-SCR was assigned to the significant contribution of highly dispersed copper species (monomeric cations and small oligomeric species) catalytically active in the oxidation of NO to NO(2,)which is necessary for fast-SCR. The zeolitic catalysts, with the higher framework alumina content, were more effective in high-temperature NH3-SCR due to their limited catalytic activity in the side reaction of ammonia oxidation.This work was supported by the National Science Centre-Poland [2016/21/B/ST5/00242].Swies, A.; Kowalczyk, A.; Rutkowska, M.; Díaz Morales, UM.; Palomares Gimeno, AE.; Chmielarz, L. (2020). Ferrierite and Its Delaminated and Silica-Intercalated Forms Modified with Copper as Effective Catalysts for NH3-SCR Process. Catalysts. 10(7):1-21. https://doi.org/10.3390/catal10070734S121107Kowalczyk, A., Święs, A., Gil, B., Rutkowska, M., Piwowarska, Z., Borcuch, A., … Chmielarz, L. (2018). 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Chemical Engineering Science, 79, 177-185. doi:10.1016/j.ces.2012.05.032Mladenović, M., Paprika, M., & Marinković, A. (2018). Denitrification techniques for biomass combustion. Renewable and Sustainable Energy Reviews, 82, 3350-3364. doi:10.1016/j.rser.2017.10.054Rutkowska, M., Pacia, I., Basąg, S., Kowalczyk, A., Piwowarska, Z., Duda, M., … Chmielarz, L. (2017). Catalytic performance of commercial Cu-ZSM-5 zeolite modified by desilication in NH 3 -SCR and NH 3 -SCO processes. Microporous and Mesoporous Materials, 246, 193-206. doi:10.1016/j.micromeso.2017.03.017Rutkowska, M., Díaz, U., Palomares, A. E., & Chmielarz, L. (2015). Cu and Fe modified derivatives of 2D MWW-type zeolites (MCM-22, ITQ-2 and MCM-36) as new catalysts for DeNO x process. Applied Catalysis B: Environmental, 168-169, 531-539. doi:10.1016/j.apcatb.2015.01.016Jodłowski, P. J., Kuterasiński, Ł., Jędrzejczyk, R. J., Chlebda, D., Gancarczyk, A., Basąg, S., & Chmielarz, L. (2017). DeNOx Abatement Modelling over Sonically Prepared Copper USY and ZSM5 Structured Catalysts. Catalysts, 7(7), 205. doi:10.3390/catal7070205Boroń, P., Chmielarz, L., & Dzwigaj, S. (2015). Influence of Cu on the catalytic activity of FeBEA zeolites in SCR of NO with NH 3. Applied Catalysis B: Environmental, 168-169, 377-384. doi:10.1016/j.apcatb.2014.12.052Martín, N., Boruntea, C. R., Moliner, M., & Corma, A. (2015). Efficient synthesis of the Cu-SSZ-39 catalyst for DeNOx applications. Chemical Communications, 51(55), 11030-11033. doi:10.1039/c5cc03200hShan, Y., Sun, Y., Du, J., Zhang, Y., Shi, X., Yu, Y., … He, H. (2020). Hydrothermal aging alleviates the inhibition effects of NO2 on Cu-SSZ-13 for NH3-SCR. Applied Catalysis B: Environmental, 275, 119105. doi:10.1016/j.apcatb.2020.119105Clark, A. H., Nuguid, R. J. G., Steiger, P., Marberger, A., Petrov, A. W., Ferri, D., … Kröcher, O. (2020). Selective Catalytic Reduction of NO with NH 3 on Cu−SSZ‐13: Deciphering the Low and High‐temperature Rate‐limiting Steps by Transient XAS Experiments. ChemCatChem, 12(5), 1429-1435. doi:10.1002/cctc.201901916Shan, Y., Du, J., Yu, Y., Shan, W., Shi, X., & He, H. (2020). Precise control of post-treatment significantly increases hydrothermal stability of in-situ synthesized cu-zeolites for NH3-SCR reaction. Applied Catalysis B: Environmental, 266, 118655. doi:10.1016/j.apcatb.2020.118655Marosz, M., Samojeden, B., Kowalczyk, A., Rutkowska, M., Motak, M., Díaz, U., … Chmielarz, L. (2020). MCM-22, MCM-36, and ITQ-2 Zeolites with Different Si/Al Molar Ratios as Effective Catalysts of Methanol and Ethanol Dehydration. Materials, 13(10), 2399. doi:10.3390/ma13102399Chmielarz, L., & Jabłońska, M. (2015). Advances in selective catalytic oxidation of ammonia to dinitrogen: a review. RSC Advances, 5(54), 43408-43431. doi:10.1039/c5ra03218kDe Pietre, M. K., Bonk, F. A., Rettori, C., Garcia, F. A., & Pastore, H. O. (2011). [V,Al]-ITQ-6: Novel porous material and the effect of delamination conditions on V sites and their distribution. Microporous and Mesoporous Materials, 145(1-3), 108-117. doi:10.1016/j.micromeso.2011.04.031Radko, M., Rutkowska, M., Kowalczyk, A., Mikrut, P., Święs, A., Díaz, U., … Chmielarz, L. (2020). Catalytic oxidation of organic sulfides by H2O2 in the presence of titanosilicate zeolites. Microporous and Mesoporous Materials, 302, 110219. doi:10.1016/j.micromeso.2020.110219Schreyeck, L., Caullet, P., Mougenel, J. C., Guth, J. L., & Marler, B. (1996). PREFER: a new layered (alumino) silicate precursor of FER-type zeolite. Microporous Materials, 6(5-6), 259-271. doi:10.1016/0927-6513(96)00032-6Ishihara, A., Hashimoto, T., & Nasu, H. (2012). Large Mesopore Generation in an Amorphous Silica-Alumina by Controlling the Pore Size with the Gel Skeletal Reinforcement and Its Application to Catalytic Cracking. 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Characteristics of the reindeer electrocardiogram

The electrocardiogram (ECG) provides reliable information about heart rate, initiation of heart beat and also, to some degree, indirect evidence on the functional state of the heart muscle. A wide range of such information is readily obtainable from conventional scalar leads, even if the records are limited to a single plane. The present investigation deals with the normal reindeer ECG in the frontal plane. The technique used is the scalar recording technique based on the Einthovenian postulates. The P wave was positive in leads II, III and aVF, negative in lead aVL and variable in leads I and aVR. The direction of the P vector was 60 to 120°. The QRS complex was variable. The most common forms of QRS complex were R and rS in leads I and aVR; R, Rs and rS in lead aVL and Qr or qR in other leads. The most common direction of the QRS vector was 240 to 300°. The T wave was variable. The duration of various intervals and deflection depended on heart rate.Elektrokardiogram på ren.Abstract in Swedish / Sammandrag: Elektrokardiogramet (EKG) ger tillförlitliga uppgifter om hjärtfrekvens, retledning och, indirekt, delvis även om hjärtmuskelns funktionell tillstånd. Största delen av denna information fås med normal skalar koppling även om registrering sker i ett plan. I detta arbete har renens normala EKG i frontalplanet undersökts. Kopplingarna har baserats på Einthovs postulat. P-vågen var riktad uppåt i koppling II, III och aVF, nedåt i koppling aVL och den varierade i koppling I och aVR. P-vektorns riktning var 60 - 120°. QRS-komplexet varierade. De vanligaste formerna var R och rS i koppling I och aVR; R, Rs och rS i koppling aVL och Qr eller qR i andra kopplingar. Vanligen var QRS-vektorns riktning 240 - 300°. T-vågen varierade. Awikelserna och intervallernas längd var beroende av hiärtfrekvenssen.Poron sydänsähkökäyrän ominaisuuksia.Abstract in Finnish / Yhteenveto: Sydänsähkökäyrästä saadaan luotettavaa tietoa sydämen syketiheydestä, sähköisestä johtumisesta ja välillisesti jossain määrin myös sydänlihaksen toiminnallisesta tilasta. Suurin osa tämänkaltaista tietoa voidaan saada tavanomaisia skalaarisia kytkentöjäkäyttäen, ja usein yhdessä tasossa tapahtuva rekisteröinti on riittävä. Tässä työssä on tutkittu porojen normaalia sydänsähkökäyrää ja sen eri poikkeamien suuntautumista frontaalitasossa, kun rekisteröinnissä on käytetty Einthovenin postulaattien mukaisia raajakytkentöjä. P aalto suuntautui ylöspäin kythkennöissä II, III ja aVF, alaspäin kytkennässä aVL ja vaihteli kytkennöissä I ja aVR. P vektorin suunta oli 60 - 120°. QRS kompleksi vaihteli. Tavallisimmat muodot olivat R ja rS kytkennöissä I ja aVR; R, Rs ja rS kytkennässä aVL ja Qr tai qR muissa kytkennöissä. Tavallisin QRS vektorin suunta oli 240 - 300°. T aalto vaihteli. Poikkeaminen ja intervallien kesto riippui sydämen syketiheydestä