Clover content and yield of swards on organic farms - maintenance and estimation

Grassland production based on legumes is an essential part of the productivity and economy of the organic farming systems. The clover content is an important factor in organic grassland management to optimize the yield, feed value and pre-crop effect of ley. The ley yield and clover content of one-, two- and three-year-old leys were determined on eight organic farms in 1998. Two-year-old leys produced the highest (6500 kg/ha dm) and three-year-old leys (4900 kg/ha dm) the lowest yields, with no significant differences between one- and two-year-old leys. The clover content (20-80 % of dm) diminished to the same extent as the yields. Because the ley samples from the organic farms gave strong evidence of decreasing yield level and clover content in the 3-year-old leys, we started to develop a technique to maintain the ley productivity in older swards. This technique includes oversowing of clover in the spring of the second ley year and utilization of lime-pelleted, pre-inoculated seed. Lime-pelleted, pre-inoculated clover seed oversown at different times in spring were compared with the aim of developing an oversowing method for Finnish conditions. The preliminary results do not show any differences, but studies are ongoing

Synthesis of modified lithium iron phosphate and its electrochemical properties

Abstract. Lithium-ion batteries (LIBs) are used to power portable electronic devices and electric vehicles (EVs). Cobalt has been an essential element on popular cathode active materials of LIBs since the commercialization of LiCoO2 (LCO) by Sony in 1991. However, most cobalt reserves and processing facilities are in Democratic Republic of Congo (DRC) and China. This creates geopolitical risks and restricts supply expansion. On top of that, child labour is used to mine cobalt in DRC. Consequently, cobalt free and low-cobalt materials should be and are developed and used for commercial applications. One of the common cobalt free materials used today is lithium iron phosphate, also known as LiFePO4 (LFP). LFP was identified as a cathode material for LIBs by Padhi, Nanjundaswamy, and Goodenough in 1997. Main advantages of LFP are its flat voltage profile, low cost, abundant material supply, environmental friendliness (nontoxic and cobalt free), and thermal stability. The downsides include relatively low theoretical capacity, low energy density, low electronic conductivity, and low ionic diffusivity. This study focuses on synthesis of modified LFP and its electrochemical properties. Common and novel synthesis methods are reviewed shortly. Especially, performance increasing modifications are reviewed. These include coating, control of particle size and particle morphology, and doping in which ions are used to replace atoms in LFP. Effects of the modifications are discussed through the paper with most time spent on doping and comparison of the effects induced by doping with different elements. In the end the dopants are ranked according to their effects on performance, price, and sustainability of a battery. To understand the modifications and their effect on electrochemical performance the structure of the material must be studied and understood. Because of this a chapter to crystallography and structure of LFP is included. Similarly, some basic information about common electrochemical characterization techniques is included to help the reader understand the plots and values produced by them. These include cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), electrode setups, and terminology

Superior Properties of Ultra-fine-grained Steels

A description of the improved mechanical properties obtained in ultra-fine-grained steels up to now will be presented in this paper, and some potential applications of these new generation steels will be described. In addition, the principle and implementation of a novel hot rolling process developed by the author will be introduced. This novel Thermomechanical Nonrecrystallisation Control Process (TNCP) has been shown to give an ultra-fine ferrite (uff) structure with grain sizes of 2 to 3mm in various test steels, thus resulting in super-toughness. Charpy V impact test results suggest that some of these steels could still be tough at temperatures lower than -100 °C. This novel process, TNCP, is one potential candidate for the commercial production of superior ultra-fine-grained steels in the future

Short review on structural analysis of activated carbon anodes for lithium-ion batteries

Abstract. In this paper, common structural analysis methods of activated carbon anodes for lithium-ion batteries are reviewed shortly. These include transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, and nitrogen adsorption-desorption. The key parameters extracted with the analysis methods are collected into a table. Basics about batteries and chemical activation of carbon are also discussed

Stop as a next-to-lightest supersymmetric particle in constrained MSSM

So far the squarks have not been detected at the LHC indicating that they are heavier than a few hundred GeVs, if they exist. The lighter stop can be considerably lighter than the other squarks. We study the possibility that a supersymmetric partner of the top quark, stop, is the next-to-lightest supersymmetric particle in the constrained supersymmetric standard model. Various constraints, on top of the mass limits, are taken into an account, and the allowed parameter space for this scenario is determined. Observing stop which is the next-to-lightest supersymmetric particle at the LHC may be difficult.Comment: v2: A few references, a plot indicating used parameters, discussion about the role of parameters in determination of the stop NLSP, CCB minima and a comment about (g-2) added. Typos corrected. Version in PR

Finger weeder for cabbage and lettuce cultures

Summer 2002 we compared finger weeder against net harrow and herbicides in cabbage. Field trial 2003 was dedicated to lettuce: we compared different intensities of finger weeding in two different lettuce cultivars

Yläkoululaisten näkemyksiä opettajan vuorovaikutuksellisesta toiminnasta luottamuksen kannalta

Tiivistelmä. Tutkimus selvittää yläkouluikäisten oppilaiden näkemyksiä opettajan vuorovaikutuksellisesta toiminnasta luottamuksen kannalta. Tavoitteena on saada selville, miten oppilaat arvioivat luottamusta opettajaa kohtaan, sekä opettajan toimintaa erilaisissa vuorovaikutustilanteissa, ja kuinka se vaikuttaa oppilaan ja opettajan väliseen luottamukseen. Lisäksi tutkimuksessa avataan näkökulmia koulussa koettuun viihtymiseen ja hyvinvointiin luottamuksen ja sosiaalisen vuorovaikutuksen näkökulmasta. Teknologian kehittyminen on vaikuttanut ihmisten vuorovaikutusmaailmaan ja tätä kautta myös luottamussuhteiden rakentumiseen. Perusopetuksen opetussuunnitelma kuitenkin erityisesti painottaa sosiaalisten taitojen merkitystä, joten luottamus- ja vuorovaikutussuhteiden analysointi on myös hyvin ajankohtaista. Lisäksi koulu toimii nuorelle merkittävänä sosiaalisen pääoman lähteenä, joten myös se huomioiden on kyseiseen aihepiiriin syventyminen varsin tärkeää. Tutkimustuloksia on mahdollista hyödyntää opettajien vuorovaikutustaitojen kehittämisen tukena, tai pohdittaessa syitä ja mahdollisuuksia sujuvamman vuorovaikutuksen sekä luottamuksen rakentamiseksi. Tutkimus toteutettiin kainuulaisella yhtenäiskoululla vuodenvaihteessa 2018–2019. Tutkimuksen aineisto koostuu kolmentoista oppilaan kokemuksista ja näkemyksistä, jotka kerättiin teemahaastatteluiden avulla. Haastateltavina henkilöinä toimivat kahdeksas- ja yhdeksäsluokkalaiset pojat ja tytöt. Teemahaastattelujen analysoinnissa käytettiin laadulliselle tutkimukselle ominaista perusmenetelmää, sisällönanalyysia. Haastatteluaineistot analysoitiin aineistolähtöisesti luokittelemalla ne luottamuksen ja sosiaalisen vuorovaikutuksen aihekokonaisuuden kautta eri teemoihin. Tutkimuksessa selvisi, että opettajan luotettavuutta ja tätä kautta luottamusta rakennetaan pitkälti opettajan henkilökohtaisten ominaisuuksien kautta. Tutkimusaineistosta nousivat esiin käyttäytymisen luotettavuuden, lähestyttävyyden ja avoimuuden, hyväluontoisuuden sekä ammatillisen osaamisen teemat. Ominaisuudet ohjaavat opettajan päivittäistä koulutyöskentelyä, ja näin ollen niissä menestyminen voi joko edistää tai purkaa luotettavaa vaikutelmaa, jolla taas on yhteys luottamuksen muodostumiseen. Lisäksi luottamuksellisilla kontakteilla ja toimivalla vuorovaikutuksella edistetään oppilaiden kokemaa viihtymistä koulussa. Tutkimuksessa havaittiin myös, että oppiaineiden välille voi muodostua viihtyvyyseroja opettajien suuren vaihtuvuuden vuoksi, mikä näkyy erityisesti perusopetuksen yläluokkien arjessa

The Behaviour of Crude Oil Spilled on Snow

Field and laboratory studies of the behavior of isothermal and hot oil spills on snow are described. Alberta crude oil spilled at 0° C is readily absorbed by snow and contaminates an area of about 0.01 square metres per litre. A hot oil spill melts a channel in the snow and flows along the ground under the snow contaminating an area of about 0.024 square metres per litre. There may be considerable spreading of the oil during thaw. The flow regimes by which oil permeates into snow and the clean-up implications are discussed