Analysis of humus balance in Lakeniidu talu’s soils

Bakalaureusetöö Põllumajandussaaduste tootmine ja turustamine õppekavalUurimistöö eesmärgiks on hinnata Lakeniidu talu huumusseisundi olukorda huumusbilansi kalkulaatori abil. Anda soovitused analüüsi tulemustest lähtuvalt ja analüüsida huumusseisundi olukorda soovituste sisseviimisel. Huumusbilansi arvutamiseks ja selle tulemi põhjal hinnangu andmisel kasutatakse Eesti Maaülikooli Põllumajandus- ja keskkonnainstituudis välja töötatud huumusbilansi kalkulaatorit. Programm on loodud tabelarvutusprogrammi MS Excel tarkvara baasil. Kalkulaatori tulem väljendatakse huumusbilansina: huumust kg/ha aastas ja huumusvaru muutusena, % algsest huumusvarust aastas. Kalkulaator võimaldab anda tulemit konkreetse põllu kui ka kogu viljavahelduse kohta. Analüüsi tegemiseks koguti Aare Kunnuselt Lakeniidu talu kohta puudutavaid andmeid nagu ettevõtte üldiseloomustus, tööjõud, maafond, kasvatatavad kultuurid, saagi andmed ja masintehnoloogia. Kalkulaatori andmebaasi sisestati PMA laboris määratud Corg ja mullastiku kaardi andmed. Huumusseisundi hindamise aluseks võeti talu viie viimase tootmisaasta (2012–2016) kultuuride saagikuse ja väetamise andmed. Töös selgus, et talu huumusbilanss vaadeldud aastatel on optimaalne, mis tagab saagikindluse ning sobib erinevatele muldadele. Positiivse huumusbilansi tagasid herne ja liblikõieliste heintaimedes kasvatamine viljavahelduses.The purpose of this reseach is to evaluate the condition of the humus in Lakeniidu talu (farm) through the humus balance calculator. To give suggestions based on the results and to analyse the conditions of the humus and to give futher suggestions how to make the suggestions a reality. Humus balance calculator, created by Institute of Agricultural and Environmental Sciences in Estonian University of Life Sciences is used to calculate the humus balance and to evaluate the results. The program is based on MS Excel software. The results are expressed through balance of the humus: humus kg/ha in a year, the change in humus supplies and percentage of humus supplies in a year. The calculator gives results by specific field and also by the whole area. To analyse the data about Lakeniidu farm, data (caracteristics of the company, workforce data, cultures grown there, data about the amount of the crops) was collected from Aare Kunnus. Corg and data about the soils were inserted to the calulator in PMA laboratory. To evaluate the condition of the humus, data about crop yield and fertilizer from the last five years (2012–2016) was taken under consideration. The research showed that the humus balance in these years was optimal, which gives us the stabiliy of the amount of crops and suits with different soils. The growing of legumes hay plants and peas gave the positive humus balance

Rahvusvaheline rakendusteatri loomeplatvorm ja konverents "Draama ühendab inimesi: teater elukestvas õppes"

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Intrinsic deviations in fluorescence yield detected x ray absorption spectroscopy the case of the transition metal L 2,3 edges

Fluorescence yield FY detected x ray absorption spectra XAS of 3d transition metal ions are calculated from the integrated 2p3d resonant x ray emission spectra. The resulting FY XAS spectra are compared with the normal XAS spectra corresponding to the absorption cross section and significant deviations between the two spectra are found. This implies that the assumption that the FY XAS spectrum identifies with the XAS spectrum is disproved. Especially for the early transition metal systems the differences between the FY XAS and XAS are large, due to the opening of inelastic decay channels from selected x ray absorption final states. The theoretical calculations show that the difference between FY detection and XAS is largest for the detection in depolarized geometry. The calculations are compared with experimental spectra for oxides and coordination compounds for Fe2C, Co2C and Ni2C systems. The implications for the sum rules in XAS and magnetic circular dichroism experiments are discusse

Density functional simulation of resonant inelastic X-ray scattering experiments in liquids : acetonitrile

In this paper we report an experimental and computational study of liquid acetonitrile (H3C-C[triple bond, length as m-dash]N) by resonant inelastic X-ray scattering (RIXS) at the N K-edge. The experimental spectra exhibit clear signatures of the electronic structure of the valence states at the N site and incident-beam-polarization dependence is observed as well. Moreover, we find fine structure in the quasielastic line that is assigned to finite scattering duration and nuclear relaxation. We present a simple and light-to-evaluate model for the RIXS maps and analyze the experimental data using this model combined with ab initio molecular dynamics simulations. In addition to polarization-dependence and scattering-duration effects, we pinpoint the effects of different types of chemical bonding to the RIXS spectrum and conclude that the H2C-C[double bond, length as m-dash]NH isomer, suggested in the literature, does not exist in detectable quantities. We study solution effects on the scattering spectra with simulations in liquid and in vacuum. The presented model for RIXS proved to be light enough to allow phase-space-sampling and still accurate enough for identification of transition lines in physical chemistry research by RIXS.In this paper we report an experimental and computational study of liquid acetonitrile (H3C-C equivalent to N) by resonant inelastic X-ray scattering (RIXS) at the N K-edge. The experimental spectra exhibit clear signatures of the electronic structure of the valence states at the N site and incident-beam-polarization dependence is observed as well. Moreover, we find fine structure in the quasielastic line that is assigned to finite scattering duration and nuclear relaxation. We present a simple and light-to-evaluate model for the RIXS maps and analyze the experimental data using this model combined with ab initio molecular dynamics simulations. In addition to polarization-dependence and scattering-duration effects, we pinpoint the effects of different types of chemical bonding to the RIXS spectrum and conclude that the H2C-C equivalent to NH isomer, suggested in the literature, does not exist in detectable quantities. We study solution effects on the scattering spectra with simulations in liquid and in vacuum. The presented model for RIXS proved to be light enough to allow phase-space-sampling and still accurate enough for identification of transition lines in physical chemistry research by RIXS.Peer reviewe

The nature of frontier orbitals under systematic ligand exchange in pseudo octahedral Fe II complexes

Understanding and controlling properties of transition metal complexes is a crucial step towards tailoring materials for sustainable energy applications. In a systematic approach, we use resonant inelastic X ray scattering to study the influence of ligand substitution on the valence electronic structure around an aqueous iron II center. Exchanging cyanide with 2 20 bipyridine ligands reshapes frontier orbitals in a way that reduces metal 3d charge delocalization onto the ligands. This net decrease of metal ligand covalency results in lower metal centered excited state energies in agreement with previously reported excited state dynamics. Furthermore, traces of solvent effects were found indicating a varying interaction strength of the solvent with ligands of different character. Our results demonstrate how ligand exchange can be exploited to shape frontier orbitals of transition metal complexes in solution phase chemistry; insights upon which future efforts can built when tailoring the functionality of photoactive systems for light harvesting application

Metalloprotein entatic control of ligand-metal bonds quantified by ultrafast x-ray spectroscopy

The multifunctional protein cytochrome c (cyt c) plays key roles in electron transport and apoptosis, switching function by modulating bonding between a heme iron and the sulfur in a methionine residue. This Fe-S(Met) bond is too weak to persist in the absence of protein constraints. We ruptured the bond in ferrous cyt c using an optical laser pulse and monitored the bond reformation within the protein active site using ultrafast x-ray pulses from an x-ray free-electron laser, determining that the Fe-S(Met) bond enthalpy is ~4 kcal/mol stronger than in the absence of protein constraints. The 4 kcal/mol is comparable with calculations of stabilization effects in other systems, demonstrating how biological systems use an entatic state for modest yet accessible energetics to modulate chemical function