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In this study, orange peel waste was successfully sulfonated with SO₃-pyridine complex in 1-allyl-3-methylimidazolium chloride ionic liquid in various reaction conditions. ¹H NMR was used to verify the occurrence of the reaction and to select the most promising material for the adsorption experiments. The degree of substitution of the sulfonated orange peel waste used for cobalt and copper removal was found to be 0.82. It was prepared with the reaction temperature and time of 70 ℃ and 60 min respectively and with the SO₃-pyridine complex to-peel waste ratio of 5:1. The selected material combined with ultrafiltration removed 98% of copper and 91% of cobalt from single metal solutions and 93% of copper and 83% of cobalt from binary metal solution at pH 5 with adsorbent dosage of 12.5 mg/100 mL and initial metal concentration of 8 mg/L. Preliminary experiments were also performed with apple pomace which was sulfonated in the conditions found best for the orange peel waste. The prepared sulfonated apple pomace proved to be almost as effective in cobalt and copper removal as sulfonated orange peel waste, removing 82% of copper and 77% of cobalt from binary metal solution with 12.5 mg/100 mL dosage at pH 5 and an initial metal concentration of 8 mg/L.

Apple pomace is a waste stream produced by fruit processing industry millions of tons annually. It is rich in carbohydrates making it a potential feedstock for the production of 5-hydroxymethylfurfural (HMF), one of the most valuable platform chemicals. In this work, the conversion of apple pomace carbohydrates to HMF was studied in a choline chloride:glycolic acid (1:3) deep eutectic solvent. To prevent undesired side reactions of HMF methyl isobutyl ketone was added to the reaction system as an extractive phase. The effect of reaction conditions, i.e., the amount of water added to the reaction system, the presence of Lewis acid co-catalyst, as well as the reaction temperature and time, on HMF yield were studied. The highest total HMF yield (44.5%) was achieved at 110 °C in 10 min with 15 wt% H₂O, and 0.01 g CrCl₃ as co-catalyst. Without the co-catalyst, the highest achieved HMF yield was 37.3% (120 °C, 20 min, 15 m% H₂O). The results indicated that apple pomace can be used as the feedstock for HMF production but the reaction procedure, especially the extraction process of HMF from deep eutectic solvent needs to be studied further.

Choline chloride (ChCl) / glycolic acid (GA) deep eutectic solvent (DES) media with high water content but without any additional catalyst are introduced in furfural and 5-hydroxymethylfurfural (HMF) production. The effects of water content, reaction time, and reaction temperature are investigated with two feedstocks: a glucose/xylose mixture and birch sawdust. Based on the results, 10 equivalent quantities of water (32.9 wt.%) were revealed to be beneficial for conversions without rupturing the DES structure. The optimal reaction conditions were 160 °C and 10 minutes for the sugar mixture and 170 °C and 10 minutes for birch sawdust in a microwave reactor. High furfural yields were achieved, namely 62 % from the sugar mixture and 37.5 % from birch sawdust. HMF yields were low, but since the characterization of the solid residue of sawdust, after DES treatment, was revealed to contain only cellulose (49 %) and lignin (52 %), the treatment could be potentially utilized in a biorefinery concept where the main products are obtained from the cellulose fraction. Extraction of products into the organic phase (methyl isobutyl ketone, MIBK) during the reaction enabled the recycling of the DES phase, and yields remained high for three runs of recycling.

Sawdust is an abundant but poorly utilized lignocellulosic side stream. It is mainly burned as energy despite the fact that it could be utilized in the production of biomass-based chemicals. Sawdust is composed of cellulose, hemicellulose, and lignin fractions, all of which can be separated and utilized for different applications. The production of so-called high-value-added chemicals from biomass could improve the economics associated with biorefinery and replace certain petroleum-based chemicals as well. Recently, the production of 5-hydroxymethylfurfural (HMF) and furfural has attracted a considerable amount of interest, as these substances can be prepared from sawdust-based sugars and play a key role in the production of many biomass-based products. The catalytic conversion of sawdust-based sugars into HMF and furfural was studied in this thesis. The comprehensive utilization of sawdust through stepwise fractionation, hydrolysis, and conversion were used, and all the reaction steps were geared toward high selectivity. In addition, different homogeneous and heterogeneous catalysts, such as mineral acids, organic acids, metal salts, catalysts based on activated carbon (AC), and deep eutectic solvents (DESs), were also utilized in this research. In the first part of the thesis, sawdust was selectively degraded to produce either hemicellulose sugars or furfural using acid hydrolysis or DES treatment. In the second part, sawdust-based sugars were converted into HMF and furfural using different AC-based catalysts or DES media. Based on the results obtained, it was demonstrated that hemicellulose could be efficiently separated as sugars and furfural from the sawdust. These processes could potentially be utilized in biorefinery concepts where the main products are currently obtained from cellulose. In addition, the selectivity of HMF and furfural production from sawdust-based sugars could be significantly improved with the use of AC catalysts in the conversion, Tiivistelmä Sahanpuru on laajasti saatavilla oleva mutta huonosti hyödynnetty lignoselluloosapitoinen sivuvirta. Se poltetaan pääasiassa energiana, vaikka se voitaisiin hyötykäyttää erilaisten biomassaperäisten tuotteiden valmistuksessa. Sahanpuru koostuu selluloosa-, hemiselluloosa- ja ligniinifraktioista, jotka voidaan erottaa toisistaan ja hyötykäyttää erilaisissa sovelluksissa. Niin sanottujen korkean lisäarvon tuotteiden valmistaminen biomassasta voisi sekä lisätä biojalostamoiden taloudellista kannattavuutta että korvata osan öljypohjaisista tuotteista biomassaperäisillä vastineilla. Viime aikoina 5-hydroksimetyylifurfuraalin (HMF) ja furfuraalin tuotanto on herättänyt paljon kiinnostusta, sillä ne voidaan valmistaa sahanpurun sisältämistä sokereista ja niillä on keskeinen rooli monien biomassaan perustuvien tuotteiden valmistuksessa. Tässä työssä tutkittiin sahanpurun sisältämien sokereiden katalyyttistä konversiota HMF:ksi ja furfuraaliksi. Sahanpuru hyödynnettiin kokonaisvaltaisesti vaiheittaisen fraktioinnin, hydrolyysin ja konversion avulla siten, että reaktioiden korkea selektiivisyys säilyi joka vaiheessa. Työssä hyödynnettiin erilaisia homogeenisia sekä heterogeenisiä katalyyttejä, kuten mineraalihappoja, orgaanisia happoja, metallisuoloja, aktiivihiilipohjaisia katalyyttejä ja syväeutektisia liuottimia (DES). Työn ensimmäisessä osassa sahanpurun hemiselluloosafraktio pilkottiin selektiivisesti joko sokereiksi tai furfuraaliksi. Tähän käytettiin happohydrolyysiä tai DES-käsittelyä. Työn toisessa osassa sahanpurun sisältämiä sokereita muunnettiin HMF:ksi ja furfuraaliksi käyttäen erilaisia aktiivihiilikatalyyttejä tai hyödyntäen syväeutektisia liuottimia. Saadut tulokset osoittivat, että hemiselluloosa voidaan erottaa sahanpurusta selektiivisesti sekä sokereina että furfuraalina. Tämä olisi hyödynnettävissä esimerkiksi biojalostamoissa, joissa nykyiset päätuotteet saadaan selluloosasta. Lisäksi tulokset osoittivat että HMF- ja furfuraalituotannon selekt

Tiivistelmä Psykiatrisia avohoidon palveluita on digitalisoitu aktiivisesti jo ennen koronavirusepidemiaa, mutta varsinkin epidemian käynnistymisen jälkeen etäasioinnin merkitys on kasvanut. Tämän poikkileikkaustutkimuksen tavoitteena oli selvittää, kuinka koronaepidemia on vaikuttanut psykiatristen avohoitokäyntien toteutusmuotoon ja kuvailla psykiatristen erikoissairaanhoidon palveluiden johtajien kokemuksia etäasioimisesta. Tutkimuksen tuloksia voidaan hyödyntää psykiatristen avohoitopalveluiden arvioinnissa sekä kehittämisessä sekä jatkotutkimuksessa. Kyselyaineisto kerättiin osana COVID-19 tilannekuvaseurantaa sähköisellä kyselylomakkeella koronaepidemian käynnistymisen jälkeen toukokuussa 2020. Kyselyssä oli sekä strukturoituja että avoimia kysymyksiä. Kyselyyn vastasi 39 aikuispsykiatrian, nuorisopsykiatrian ja lasten psykiatrian toimialojen esimiestä ja johtajaa 19 eri sairaanhoitopiiristä. Kvantitatiiviset kysymykset avohoitokäyntien toteutusmuotojen määrästä raportoitiin prosenttiosuuksina ja avointen kysymysten vastaukset analysointiin induktiivisella sisällönanalyysillä. Tulosten perusteella etäasioinnin suhteellinen osuus kaikista asiointitavoista kasvoi voimakkaasti koronaepidemian käynnistymisen jälkeen. Psykiatrisista avohoitokäynneistä toteutettiin puhelimitse tai etäyhteydellä tammikuussa 9% ja toukokuussa 48% (39 prosenttiyksikön kasvu). Etäasiointia haastoivat välineiden riittämättömyys ja toimimattomat ohjelmat, asiakkaiden puuttuvat laitteet, yhteydet ja tilat, etäasioinnin soveltumattomuus kaikkeen toimintaan, ammattihenkilöiden ja asiakkaiden negatiivinen asennoituminen, riittämätön osaaminen etäasioinnin käyttöön ja organisatoriset ongelmat. Etäasiointia edistivät asiakkaiden ja ammattihenkilöiden myönteinen asenne ja ilmapiiri, koronaepidemian aiheuttama tarve etäasioinnille, etäasioinnin soveltuvuus ja tuttuus psykiatrisissa avohoitopalveluissa, asiakkaiden aikaisempi tuntemus, pitkät välimatkat, toimivat etäverkostot ja ajansäästö, toimiv, Psychiatric outpatient care has been actively digitalized even before the COVID-19 outbreak. However, COVID-19 has increased the adoption of digital and remote health services. The aim of this cross-sectional study was to examine whether COVID-19 has impacted on the form of psychiatric outpatient services and describe psychiatric healthcare leaders’ experiences of digital and remote services. The results of this study can be used to evaluate and develop psychiatric outpatient services and to facilitate further research. The data was collected through an online survey after the COVID-19 outbreak in May 2020. The questionnaire contained structured and open-ended questions. A total of 39 adult psychiatric, youth psychiatric and pediatric psychiatric service leaders answered the survey from 19 different health care districts. Quantitative questions about the forms of psychiatric outpatient services were reported using percentages, whereas open-ended questions were analyzed using inductive content analysis. The results showed that the relative amount of digital and remote services increased after the COVID-19 outbreak. Of the psychiatric outpatient visits, 9 % were conducted using phone or remote access in January and 48 % in May (rose by 39 percentage units). The challenges for using remote services were related to the lack of IT equipment and inoperative programs, customers’ lack of devices, connections and room, remote services’ unsuitability for all operations, negative attitude of professionals and customers, insufficient IT knowledge, and organizational problems. The supporters of remote service usage were related to customers’ and professionals’ positive attitude and atmosphere, the necessity for the remote services caused by the COVID-19, suitability and familiarity of remote services in psychiatry, familiarity of the customers, long distances, well-functioning remote networks and time savings, functional technology, programs and devices, and sufficient

In this study, conversion of xylose to furfural was studied using lignin-based activated carbon-supported iron catalysts. First, three activated carbon supports were prepared from hydrolysis lignin with different activation methods. The supports were modified with different metal precursors and metal concentrations into five iron catalysts. The prepared catalysts were studied in furfural production from xylose using different reaction temperatures and times. The best results were achieved with a 4 wt% iron-containing catalyst, 5Fe-ACs, which produced a 57% furfural yield, 92% xylose conversion and 65% reaction selectivity at 170 °C in 3 h. The amount of Fe in 5Fe-ACs was only 3.6 µmol and using this amount of homogeneous FeCl₃ as a catalyst, reduced the furfural yield, xylose conversion and selectivity. Good catalytic activity of 5Fe-ACs could be associated with iron oxide and hydroxyl groups on the catalyst surface. Based on the recycling experiments, the prepared catalyst needs some improvements to increase its stability but it is a feasible alternative to homogeneous FeCl₃.

Selective and efficient dehydration of glucose to 5-hydroxymethylfurfural (HMF) has been widely explored research problem recently, especially from the perspective of more sustainable heterogeneous catalysts. In this study, activated carbon was first produced from a lignocellulosic waste material, birch sawdust. Novel heterogeneous catalysts were then prepared from activated carbon by adding Lewis or Brønsted acid sites on the carbon surface. Prepared catalysts were used to convert glucose to HMF in biphasic water:THF system at 160 °C. The highest HMF yield and selectivity, 51% and 78%, respectively, were obtained in 8 h with a catalytic mixture containing both Lewis and Brønsted acid sites. Also, preliminary recycling experiments were performed. Based on this study, biomass-based activated carbon catalysts show promise for the conversion of glucose to HMF.

Enormous amounts of fiber sludge are generated annually by the pulp industry as a by-product. As a cellulose-rich material, its current usage, mainly as fuel, is inefficient from a material efficiency point of view. This work studied the utilization of fiber sludge from a Finnish and a Swedish pulp mill as a potential feedstock to produce levulinic acid, a valuable platform chemical. The conversion experiments of fiber sludge to levulinic acid were performed in a microwave reactor with a mixture of H2SO4 and Lewis acid as the catalyst. The reaction conditions, which included reaction time and temperature as well as the H2SO4 and Lewis acid concentrations, were studied in detail. The highest levulinic acid yield, 56%, was obtained with Swedish fiber sludge after 60 min at 180 °C with the H2SO4 concentration of 0.3 mol/L and a CrCl3 concentration of 7.5 mmol/L which indicated that the fiber sludge had the potential to be used as feedstock for levulinic acid production.

Protic ionic liquids (ILs) with seven-membered azepanium cation were synthesized and characterized. The molecular structure of the synthesized ILs was confirmed using 1H NMR and 13C NMR spectroscopy. In one hand, sulfonic acid (SO3H) group was tethered to the azepanium moiety combined with HSPO4 or H2PO4−anion and on the other hand azepanium based alkyl sulfate ILs were synthesized by reacting azepane with corresponding dialkyl sulfates. Thermo-physical properties (density, viscosity, glass transition temperature, thermal decomposition temperature) of the synthesized ILs were measured. All the studied ILs showed good thermal stability. From the viscosity and density data of alkyl sulfate ILs, the volumetric properties such as molar volume, lattice energy and standard molar entropy were calculated. COSMO-RS was used to predict hydrogen bonding energy, interaction energy, Van der Waals energy and H-bond accepting and H-bond donating nature of these pure ILs. Activity coefficient values have also predicted for these ILs with cellulose.

Inspired by a recent approach for genome reconstruction from incomplete data, we consider a variant of the longest common subsequence problem for the comparison of two sequences, one of which is incomplete, i.e. it has some missing elements. The new combinatorial problem, called Longest Filled Common Subsequence, given two sequences A and B, and a multiset M of symbols missing in B, asks for a sequence B∗ obtained by inserting the symbols of M into B so that B∗ induces a common subsequence with A of maximum length. First, we investigate the computational and approximation complexity of the problem and we show that it is NP-hard and APX-hard when A contains at most two occurrences of each symbol. Then, we give a 3/5-approximation algorithm for the problem. Finally, we present a fixed-parameter algorithm, when the problem is parameterized by the number of symbols inserted in B that "match" symbols of A.

In this work, untreated starch-rich potato peel waste was used as a starting material in preparation of cationized starch (CS¹) in water solution with 2-chloro-3-hydroxypropyltrimethylammonium chloride (CHPTAC) as the cationization reagent. The impact of various factors (activation time, temperature, reaction time, the amount of CHPTAC and NaOH) on the degree of substitution (DS) of CS was studied by using experimental design. The DS values were determined by ¹H NMR. The highest DS (0.40) was obtained when the reaction time was 8 h, temperature 30 °C, the molar ratio of CHPTAC and NaOH to AGU 3 and 3.75, respectively. The prepared CS was successfully used to remove sulfate ions from an aqueous solution with ultrafiltration technique. Sulfate is a major pollutant of water bodies so development of efficient techniques for its removal is detrimental. The removal of sulfate in study was 74% at best.

V-order is a global order on strings related to Unique Maximal Factorization Families (UMFFs), themselves generalizations of Lyndon words. VV-order has recently been proposed as an alternative to lexicographic order in the computation of suffix arrays and in the suffix-sorting induced by the Burrows–Wheeler transform. Efficient VV-ordering of strings thus becomes a matter of considerable interest. In this paper we discover several new combinatorial properties of VV-order, then explore the computational consequences; in particular, a fast, simple on-line VV-order comparison algorithm that requires no auxiliary data structures.

Starch is one of the most abundant polysaccharides found in nature and is widely utilized in various fields of industry. Due to the complex structure of native starch it is insoluble in most organic solvents and needs modification prior utilization. In this study, ionic liquids (ILs), modern green chemistry alternatives for common solvents were used as reaction media in starch modification. At first various starch species were depolymerized in 1-allyl-3-methylimidazolium chloride ([AMIM]Cl) with p-TsOH as a catalyst. Microwave activation or conventional bath heating were used as heating methods while HPLC-ELSD was used as an analytical method. All studied starch species depolymerized similarly into water-soluble starch oligomers while microwave activation shortened the depolymerization time considerably compared to oil bath heating. Barley starch was chosen for further experiments, in which various ILs were studied as potential media for starch dissolution and depolymerization. Results suggested that both the anion and the cation part of the IL had an effect on the dissolution and depolymerization of barley starch. After the depolymerization reactions, the depolymerized barley starch was further modified by cationization. [AMIM]Cl was used as the reaction media, microwave activation as the heating method while HPLC-ELSD, 1H NMR and elemental analysis were used as analytical methods. The modified products had DS values from 0.2 to 0.5 depending on the reaction conditions. The products were studied as potential binding agents for heavy metal ions which showed that moderately substituted modified starch (DS 0.4) could be used to bind Cu(II), Fe(III) and Zn(II) ions from an aqueous solution. Finally, potato peel waste was studied as an alternative starch source to produce cationized starch for wastewater purification. Peel waste was pre-treated by alkaline depolymerization after which it was cationized in a water solution to produce cationized products with DS, Tiivistelmä Tärkkelys on yksi yleisimmistä luonnossa esiintyvistä polysakkarideista. Sitä hyödynnetään useilla eri teollisuuden aloilla. Monimutkaisen rakenteensa vuoksi tärkkelys on liukenematon useimpiin orgaanisiin liuottimiin ja veteen, minkä vuoksi sitä täytyy modifioida ennen käyttöä. Tässä väitöstutkimuksessa tärkkelyksen modifioinnissa käytettiin ionisia nesteitä reaktioväliaineena. Tutkimuksen alussa eri tärkkelyslajeja depolymeroitiin 1-allyyli-3-metyyli-imidatsoliumkloridissa ([AMIM]Cl) katalyyttinä p-TsOH. Mikroaaltoaktivointia ja haudekuumennusta käytettiin vaihtoehtoisina lämmitysmenetelminä. Reaktion edistymistä ja tuotteiden muodostumista tutkittiin HPLC-ELSD -menetelmällä. Eri tärkkelyslajit depolymeroituivat samankaltaisesti vesiliukoisiksi, lyhytketjuisiksi tärkkelysoligomeereiksi. Mikroaaltoaktivointi lyhensi reaktioaikaa haudekuumennukseen verrattuna. Tutkimuksen seuraavassa vaiheessa tutkittiin ohratärkkelyksen liukoisuutta ja depolymeroitumista eri ionisissa nesteissä. Tulosten perusteella ionisen nesteen sekä anioni- että kationiosa vaikuttivat tärkkelyksen liukenemiseen. Depolymeroidun ohratärkkelyksen modifiointitutkimuksia jatkettiin [AMIM]Cl:ssa kationisoinnilla. Lämmitysmenetelmänä käytettiin mikroaaltoaktivointia. Tuotteet tutkittiin käyttäen alkuaineanalyysiä sekä HPLC-ELSD- että 1H NMR-tekniikoita. Kationisoitujen tuotteiden substituutioaste (DS) vaihteli reaktio-olosuhteista riippuen välillä 0.2–0.5. Saatuja tuotteita tutkittiin raskasmetalli-ionien sitomisessa vesiliuoksesta. Havaittiin, että kohtalaisesti substituoitu (DS 0.4) modifioitu tärkkelys sitoi Cu(II)-, Fe(III)- ja Zn(II)-ioneja vesiliuoksesta. Tutkimuksen loppuosassa tutkittiin perunan kuorijätettä vaihtoehtoisena tärkkelyslähteenä kationisoidun tärkkelyksen valmistamisessa. Kuorijäte esikäsiteltiin kuumentamalla se emäksisessä etanoliliuoksessa, minkä jälkeen sille suoritettiin kationisointi vesiliuoksessa. Kationisten tuotteiden substituutioasteet vaihtelivat välillä 0–