The A˚bo Akademi Database: Fuel Characterization

2005 ◽  
Author(s):  
Maria Zevenhoven ◽  
Patrik Yrjas ◽  
Rainer Backman ◽  
Bengt-Johan Skrifvars ◽  
Mikko Hupa
Keyword(s):  
Trace Metals ◽  
Ammonium Acetate ◽  
Chemical Fractionation ◽  
Ash Deposition ◽  
Agricultural Crops ◽  
Insufficient Information ◽  
The Past ◽  
Fuel Characterization ◽  
Leaching Procedure

Standard fuel analyses have shown to provide insufficient information for proper prediction of ash deposition. Therefore, chemical fractionation, i.e. a stepwise leaching procedure, has been developed in the past. It has been used extensively for determination of the distribution of ash forming matter both in coal, peat, waste and biomass fuels. With this method fuels are leached in three steps, i.e. leached with water, ammonium acetate and hydro chloric acid respectively. This paper presents the fuel database developed at A˚bo Akademi University. The database contains over 100 fuels, i.e. coal, peat, bark, wood derived fuels, agricultural crops and waste fuels. Standard fuel analyses, stepwise leaching results, thermodynamic melting calculations and SEM pictures are available for the majority of these fuels. For 11 fuels also trace metals were analyzed.

Chemical Forms of Ash-Forming Matter in Woody Fuels for FBC

2005 ◽  
Author(s):  
Johan Werkelin ◽  
Maria Zevenhoven ◽  
Bengt-Johan Skrifvars ◽  
Mikko Hupa
Keyword(s):  
Hydrochloric Acid ◽  
Ammonium Acetate ◽  
Ionic Species ◽  
Water Soluble ◽  
Chemical Fractionation ◽  
Soluble Calcium ◽  
Combustion Processes ◽  
Low Solubility ◽  
Leaching Procedure

The prediction of the ash behavior in combustion processes is enhanced by the determination of the ash-forming matter in the fuel. The scope of this work was to characterize Scandinavian wood fuels by studying the wood, bark and leaves from a spruce and an aspen. Chemical Fractionation, a step-wise leaching procedure that treat the fuel in water, ammonium acetate and hydrochloric acid, was used to determine the solubility of the ash elements. The resulting solutions were further analyzed on ionic species, which was coupled to the presence of salt compounds in the original biomass tissues. The leaching procedure dissolved nearly 100% of the ash-forming matter. The phosphorus (P), chlorine (Cl) and some of the sulfur (S) were readily leached with water and found present as HPO42−, SO42− and Cl− in the solutions. The simultaneous dissolving of potassium (K) in this step proved the presence of water soluble potassium salts in the biomasses. The remaining K after the water treatment and all magnesium (Mg) dissolved completely in the ammonium acetate step together with a large part of the tissues’ calcium (Ca) and manganese (Mn). The remaining Ca after the second step was leached in hydrochloric acid together with equivalent amounts of oxalate ions, C2O42−. This proved the presence of acid soluble calcium oxalate in the tissues, a salt with low solubility in neutral pH.

Appearance of Trace Elements in Co-Firing Fuels

2005 ◽  
Author(s):  
Maria Zevenhoven ◽  
Rainer Backman ◽  
Bengt-Johan Skrifvars ◽  
Mikko Hupa
Keyword(s):  
Trace Elements ◽  
Sewage Sludge ◽  
Ammonium Acetate ◽  
Chloric Acid ◽  
Thermodynamic Calculations ◽  
Chemical Fractionation ◽  
Forest Residue ◽  
Impregnated Wood ◽  
Leaching Procedure

With the implementation of new EU guidelines the levels of maximum allowable emission levels of Cd, Tl, Hg, Sb, As, Pb, Cr, Co, Cu, Mn, Ni, V will be further restricted. This may have implications for co-combustion of coal with waste derived fuels. In this study chemical fractionation, i.e. a stepwise leaching procedure has been applied on coal, peat, sewage sludge, bark, impregnated wood and forest residue. With this method fuels are leached in three steps, i.e. leached with water, ammonium acetate and hydro chloric acid, respectively. Both solubility in different leaching agents of main ash forming matter and the trace elements Cd, Tl, Hg, Sb, As, Pb, Cr, Co, Cu, Mn, Ni, V and Zn were studied. In this way more information became available about the characteristics of co-firing fuels. Thermodynamic calculations were used to show the consequences of the interaction with main ash forming elements on the partition of Cd, Hg, Pb and Zn in the gas/ash phase.

The determination of exchangeable aluminium in soils

Soil Research ◽  
1964 ◽  
Vol 2 (1) ◽  
pp. 76 ◽  
Author(s):  
I Little
Keyword(s):  
Potassium Chloride ◽  
Sodium Hydroxide ◽  
Potentiometric Titration ◽  
Ammonium Acetate ◽  
Ph Dependent ◽  
Aluminium Compound ◽  
Leaching Procedure

A leaching procedure employing 1N potassium chloride was found to yield satisfactory estimates of exchangeable aluminium in subsoil samples. The use of 1N ammonium acetate solutions as extractants was not recommended. When buffered at pH 4.8 these solutions gave low results, whereas at pH 4.0 there was some attack on hydroxy-aluminium polymers, which led to erroneous results, particularly in sesquioxidic soils. Satisfactory estimates of exchangeable aluminium in subsoils were obtained by potentiometric titration of soil suspensions in 1N potassium chloride with 0.1N sodium hydroxide, provided allowance was made for the contribution of pH-dependent charge between pH 4.0 and 5.5. This procedure gave values consistently lower than those obtained by leaching with 1N potassium chloride, and of the order of 81 % of these. This was consistent with the formation of an aluminium compound with the formula Ak6(OH)153+ whose existence has been postulated by other workers.

Transmission Electron Microscopy of Protein Macromolecules

1971 ◽  
Vol 29 ◽  
pp. 424-425
Author(s):  
Henry S. Slayter
Keyword(s):  
Biological Systems ◽  
Metal Vapor ◽  
Resolving Power ◽  
Electron Microscopic ◽  
Chemical Methods ◽  
Molecular Weights ◽  
The Past ◽  
Physical Chemical ◽  
Transmission Electron

Electron microscopic methods have been applied increasingly during the past fifteen years, to problems in structural molecular biology. Used in conjunction with physical chemical methods and/or Fourier methods of analysis, they constitute powerful tools for determining sizes, shapes and modes of aggregation of biopolymers with molecular weights greater than 50, 000. However, the application of the e.m. to the determination of very fine structure approaching the limit of instrumental resolving power in biological systems has not been productive, due to various difficulties such as the destructive effects of dehydration, damage to the specimen by the electron beam, and lack of adequate and specific contrast. One of the most satisfactory methods for contrasting individual macromolecules involves the deposition of heavy metal vapor upon the specimen. We have investigated this process, and present here what we believe to be the more important considerations for optimizing it. Results of the application of these methods to several biological systems including muscle proteins, fibrinogen, ribosomes and chromatin will be discussed.

LC–MS/MS Determination of Apigenin in Rat Plasma and Application to Pharmacokinetic Study

2020 ◽  
Vol 21 ◽  
Author(s):  
Shixing Zhu ◽  
Jiayuan Zhang ◽  
Zhihua Lv ◽  
Mingming Yu
Keyword(s):  
Formic Acid ◽  
Pharmacokinetic Study ◽  
Ammonium Acetate ◽  
Rat Plasma ◽  
Biological Properties ◽  
Plasma Samples ◽  
Supply Rate ◽  
Natural Plant ◽  
Ammonium Acetate Buffer

Background: Apigenin, a natural plant flavone, has been shown to possess a variety of biological properties. Objective: In this report, a highly selective and sensitive LC-MS/MS method was developed and validated for the determination of apigenin in rat plasma. Methods: Analysts were separated on the HSS T3 column (1.8 μm 2.1×100 mm) using acetonitrile and 0.1% formic acid in 2 mM ammonium acetate buffer at a supply rate of 0.200 mL/min as eluent in gradient model. Results: Plasma samples were treated by protein precipitation using acetonitrile for the recovery ranging from 86.5% to 90.1% for apigenin. The calibration curves followed linearity in the concentration range of 0.50-500 ng/mL. The inter-day and intra-day precisions at different QC levels within 13.1% and the accuracies ranged from -10.6% to 8.6%. Conclusion: The assay has been successfully applied to the pharmacokinetic study of apigenin in rats.

Crime and Punishment

2017 ◽  
Author(s):  
Richard Adelstein
Keyword(s):  
Criminal Liability ◽  
Court Case ◽  
Efficient Allocation ◽  
Two Stage ◽  
Crime And Punishment ◽  
The Past ◽  
Ex Post ◽  
Ex Ante ◽  
Supreme Court Case

This chapter elaborates the operation of criminal liability by closely considering efficient crimes and the law’s stance toward them, shows how its commitment to proportional punishment prevents the probability scaling that systemically efficient allocation requires, and discusses the procedures that determine the actual liability prices imposed on offenders. Efficient crimes are effectively encouraged by proportional punishment, and their nature and implications are examined. But proportional punishment precludes probability scaling, and induces far more than the systemically efficient number of crimes. Liability prices that match the specific costs imposed by the offender at bar are sought through a two-stage procedure of legislative determination of punishment ranges ex ante and judicial determination of exact prices ex post, which creates a dilemma: whether to price crimes accurately in the past or deter them accurately in the future. An illustrative Supreme Court case bringing all these themes together is discussed in conclusion.

Sampling, Preservation and Counting of Samples II: Zooplankton

2017 ◽  
Author(s):  
Peter H. Wiebe ◽  
Ann Bucklin ◽  
Mark Benfield
Keyword(s):  
Genetic Analysis ◽  
High Speed ◽  
Morphological Analysis ◽  
Taxonomic Composition ◽  
Sampling Techniques ◽  
Sample Analysis ◽  
Sample Preservation ◽  
The Past ◽  
Plankton Collection

This chapter reviews traditional and new zooplankton sampling techniques, sample preservation, and sample analysis, and provides the sources where in-depth discussion of these topics is addressed. The net systems that have been developed over the past 100+ years, many of which are still in use today, can be categorized into eight groups: non-opening/closing nets, simple opening/closing nets, high-speed samplers, neuston samplers, planktobenthos plankton nets, closing cod-end samplers, multiple net systems, and moored plankton collection systems. Methods of sample preservation include preservation for sample enumeration and taxonomic morphological analysis, and preservation of samples for genetic analysis. Methods of analysis of zooplankton samples include determination of biomass, taxonomic composition, and size by traditional methods; and genetic analysis of zooplankton samples.

scholarly journals Analysis of the Mycosporine-Like Amino Acid (MAA) Pattern of the Salt Marsh Red Alga Bostrychia scorpioides

Marine Drugs ◽  
2021 ◽  
Vol 19 (6) ◽  
pp. 321
Author(s):  
Maria Orfanoudaki ◽  
Anja Hartmann ◽  
Julia Mayr ◽  
Félix L. Figueroa ◽  
Julia Vega ◽  
...  
Keyword(s):  
Amino Acids ◽  
High Performance Liquid Chromatography ◽  
High Performance ◽  
Red Alga ◽  
Array Detector ◽  
Diode Array ◽  
Diode Array Detector ◽  
The Past ◽  
Specific Species

This study presents the validation of a high-performance liquid chromatography diode array detector (HPLC-DAD) method for the determination of different mycosporine-like amino acids (MAAs) in the red alga Bostrychia scorpioides. The investigated MAAs, named bostrychines, have only been found in this specific species so far. The developed HPLC-DAD method was successfully applied for the quantification of the major MAAs in Bostrychia scorpioides extracts, collected from four different countries in Europe showing only minor differences between the investigated samples. In the past, several Bostrychia spp. have been reported to include cryptic species, and in some cases such as B. calliptera, B. simpliciuscula, and B. moritziana, the polyphyly was supported by differences in their MAA composition. The uniformity in the MAA composition of the investigated B. scorpioides samples is in agreement with the reported monophyly of this Bostrychia sp.

scholarly journals The Past, Present and Future of Flow Cytometry in Central Nervous System Malignancies

2021 ◽  
Vol 4 (1) ◽  
pp. 11
Author(s):  
Evrysthenis Vartholomatos ◽  
George Vartholomatos ◽  
George A. Alexiou ◽  
Georgios S. Markopoulos
Keyword(s):  
Central Nervous System ◽  
Flow Cytometry ◽  
Nervous System ◽  
Therapeutic Agents ◽  
Phenotypic Characterization ◽  
Cell Phenotype ◽  
Analytical Technique ◽  
The Past ◽  
Current Review

Central nervous system malignancies (CNSMs) are categorized among the most aggressive and deadly types of cancer. The low median survival in patients with CNSMs is partly explained by the objective difficulties of brain surgeries as well as by the acquired chemoresistance of CNSM cells. Flow Cytometry is an analytical technique with the ability to quantify cell phenotype and to categorize cell populations on the basis of their characteristics. In the current review, we summarize the Flow Cytometry methodologies that have been used to study different phenotypic aspects of CNSMs. These include DNA content analysis for the determination of malignancy status and phenotypic characterization, as well as the methodologies used during the development of novel therapeutic agents. We conclude with the historical and current utility of Flow Cytometry in the field, and we propose how we can exploit current and possible future methodologies in the battle against this dreadful type of malignancy.

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