Factors influencing burglary and home security measures in England and Wales

Objectives: This exploratory study aims to investigate the relationship between characteristics of the survey respondents, reported fear of burglary and installed home security measures. Methods: This is a secondary analysis research on data from the Crime Survey for England and Wales 2017/18. The data was analysed using suitable statistical methods: regression modelling and factor analysis. Results: The main findings showed that the socioeconomic status of respondents and the status of the area they live in are the strongest predictors of installation of deterrence home security measures. The findings further revealed that those of lower socioeconomic status are more afraid of burglary and more likely to have deterrence but not entry prevention home security installed. However, the direct impact of fear of burglary on deterrence home security measures indicated a decrease on the likelihood of this type of home security measure being installed. This suggests that affordability of home security measures plays an important role. Conclusion: Participants from lower socioeconomic status are more afraid of becoming victims of burglary and invest in cheaper home security measures to protect their homes, while wealthier participants do not feel the need to protect their homes since they are more likely to live in low crime areas

Magnetic resonance imaging-guided phase 1 trial of putaminal AADC gene therapy for Parkinson's disease.

ObjectiveTo understand the safety, putaminal coverage, and enzyme expression of adeno-associated viral vector serotype-2 encoding the complementary DNA for the enzyme, aromatic L-amino acid decarboxylase (VY-AADC01), delivered using novel intraoperative monitoring to optimize delivery.MethodsFifteen subjects (three cohorts of 5) with moderately advanced Parkinson's disease and medically refractory motor fluctuations received VY-AADC01 bilaterally coadministered with gadoteridol to the putamen using intraoperative magnetic resonance imaging (MRI) guidance to visualize the anatomic spread of the infusate and calculate coverage. Cohort 1 received 8.3 × 1011 vg/ml and ≤450 μl per putamen (total dose, ≤7.5 × 1011 vg); cohort 2 received the same concentration (8.3 × 1011 vg/ml) and ≤900 μl per putamen (total dose, ≤1.5 × 1012 vg); and cohort 3 received 2.6 × 1012 vg/ml and ≤900 μl per putamen (total dose, ≤4.7 × 1012 vg). (18)F-fluoro-L-dihydroxyphenylalanine positron emission tomography (PET) at baseline and 6 months postprocedure assessed enzyme activity; standard assessments measured clinical outcomes.ResultsMRI-guided administration of ascending VY-AADC01 doses resulted in putaminal coverage of 21% (cohort 1), 34% (cohort 2), and 42% (cohort 3). Cohorts 1, 2, and 3 showed corresponding increases in enzyme activity assessed by PET of 13%, 56%, and 79%, and reductions in antiparkinsonian medication of -15%, -33%, and -42%, respectively, at 6 months. At 12 months, there were dose-related improvements in clinical outcomes, including increases in patient-reported ON-time without troublesome dyskinesia (1.6, 3.3, and 1.5 hours, respectively) and quality of life.InterpretationNovel intraoperative monitoring of administration facilitated targeted delivery of VY-AADC01 in this phase 1 study, which was well tolerated. Increases in enzyme expression and clinical improvements were dose dependent. ClinicalTrials.gov Identifier: NCT01973543 Ann Neurol 2019;85:704-714

Zastosowanie teorii QTAIM i SAPT w analizie wiązań wodorowych wspomaganych ładunkiem

Zdigitalizowano i udostępniono w ramach projektu pn. Rozbudowa otwartych zasobów naukowych Repozytorium Uniwersytetu w Białymstoku, dofinansowanego z programu „Społeczna odpowiedzialność nauki" Ministra Edukacji i Nauki na podstawie umowy SONB/SP/512497/2021.The hydrogen bond (H-bond) has been probably most thoroughly investigated among different so-calIed "weak interactions". This is due to the fact that H-bond plays an essential role in many physical, chemical and biological processes. The strongest and, therefore, the most effectively affecting physical and chemical properties of interacting molecules, are those assisted by some additional effects, e.g. the resonance-assisted H-bonds (RAHBs) or the charge-assisted H-bonds (CAHBs). The latter occurs when the distribution of formal charges additionalIy favors H -bonding. A good example of such interaction may be the NH₄⁽⁺⁾ ... Cl⁽⁻⁾ CAHB(+/-) which can be found in crystal structure of ammonium chloride.The charge-assisted hydrogen bond (CAHB) was investigated for a set of H-bridges of D-H ... X (D=N, P, X=CI, Br) type by the use of computational methods: QTAIM and SAPT. The properties of these bonds, i.e. the interaction energy and its components and the electron density measured in a characteristic point of the chemical bond (band critical points), were represented as functions of H ... CI distance. This gives an opportunity to estimate and discuss the influence of formal charge on the energetic and topological characteristics of H-bonds. It was found that the energy of interaction is strongly affected by formaI charges, which is caused by the presence of effective interaction between formal ions. However, the electron density measured in the H-bond critical point seems to be totalIy independent of the formal charges. The decomposition of interaction energy performed for alI studied CAHBs systems shows that the electrostatic interaction is obviously the main attractive force in CAHB(+/-) and CAHB(-) H-bridges. The contribution of induction effect plays a crucial role in the stabilities of CAHB(+) H-bridge and the dispersion contribution is the main factor stabilizing non-charge-assisted H₃N∙∙∙HCI complex. AdditionalIy, the results of interaction energy decomposition were confronted against QTAIM characteristics of H-BCPs. This manuscript is a smalI review on the theoretical characteristic for a set of charge-assisted hydrogen bond (CAHB) of D-H ... X (D=N, P, X=Cl, Br) type.Wiązania wodorowe odgrywają zasadniczą rolę w wielu fizycznych, chemicznych oraz biologicznych procesach. Z tego względu należą do najczęściej badanych słabych oddziaływań. Najsilniejsze i za razem najefektywniej wpływające na fizykochemiczne właściwości oddziałujących cząsteczek są wiązania wodorowe, którym towarzyszą efekty wspomagające. Wśród nich możemy wyróżnić wiązania wspomagane rezonansem (RAHB) lub ładunkiem formalnym (CAHB). Te ostatnie pojawiają się, gdy obecność ładunku formalnego dodatkowo sprzyja tworzeniu się wiązania wodorowego. Dobrym przykładem wiązań wodorowych wspomaganych ładunkiem są oddziaływania między jonem amonowym i chlorkowym (NH₄⁽⁺⁾∙∙∙Cl⁽⁻⁾ CAHB(+/-)) występujące w strukturze krystalicznej chlorku amonu. Poniższy artykuł ma charakter przeglądowy i przedstawia wyniki teoretycznych badań dotyczących wiązań wodorowych wspomaganych ładunkiem typu D¬ -H•••X, gdzie D=N, P oraz X=CI, Br. Analizę oparto na Kwantowej Teorii Atomów w Cząsteczkach (QTAIM) oraz Teorii Zaburzeń Adaptowanej Symetrii (SAPT) zaliczanych do najbardziej zaawansowanych metod w chemii obliczeniowej stosowanych do opisu oddziaływań międzymolekularnych. Właściwości wiązań takie jak energia oddziaływania i jej składowe oraz gęstość elektronowa mierzona w punktach krytycznych wiązań wyrażono jako funkcję długości mostków wodorowych H•• •X. W ten sposób określono jaki wpływ ma obecność ładunku formalnego na energetyczne i topologiczne parametry międzycząsteczkowych wiązań wodorowych. Szczegółowo omówiono udział poszczególnych energetycznych składowych oddziaływań (elektrostatycznej, indukcyjnej i dyspersyjnej) w stabilizacji wiązania wodorowego. Przedstawiono korelację gęstości elektronowej z wymienionymi składowymi oddziaływań w badanych układach. W oparciu o wyniki badań wskazano liniowe zależności między gęstością elektronową w obrębie wiązania wodorowego a indukcyjnym i dyspersyjnym wkładem do energii oddziaływania. Brak jest natomiast zależności pomiędzy gęstości elektronową a energią oddziaływania elektrostatycznego. Zaprezentowane wyniki oparto na obliczeniach wykonanych za pomocą metod rachunku zaburzeń Møllera-Plesseta drugiego rzędu oraz sprzężonych klasterów przy użyciu bazy funkcyjnej Dunninga uwzględniającej funkcje dyfuzyjne.Instytut Chemii, Uniwersytet w BiałymstokuBader R.F.W., Atoms in Molecules. A Quantum Theory, Clarendon Press, 1994.Desiraju G. R., Steiner T. , The weak hydrogen bond in structural chemistry and biology, Oxford University Press, New York, 1999.Gilli G., .Gilli P, The Nature of Hydrogen Bond, Oxford University Press, Oxford, U.K., 2010.Jeffrey G. A, An introduction to hydrogen bonding. Topics in Physical Chemistry, Oxford University Press, New York, 1997.Pauling C.L., Nature of the Chemical Bond and the Structure of Molecules and Crystals: An Introduction to Modern Structural Chemistry, 3rd ed. , Comell University Press, Ithaca, NY, 1960, s. 449-504, pierwsze wydanie w 1939Piela L., Idee Chemii Kwantowej, PWN S.A., Warszawa, 2003 .Popelier P. , Atoms in Molecules. An Introduction, Pearson Education Limited, Prentice Hall, 2000.Nishio M., Hirota M., Umezawa Y., The CH/ℼ Interaction, Evidence, Nature, and Consequences, Wiley-VCH, New York, 1998Scheiner S., Hydrogen bonding:A Teoretical Perspective, Oxford University Press, New York, 1997.S. Scheiner, Intermolecular Interactions - From Van der Waals to Strongly Bound Complexes, Wiley-VCH: Weinheim, New York, 1997.Bukowski R., Cencek W., Jankowski P. , Jeziorska M., Jeziorski B.,. Kucharski S.A, Lotrich V.F. ,.Misquitta A.J, R. Moszyński, Patkowski K., Podeszwa R., Rybak S., Szalewicz K., Williams H.L.,. Wheatley RJ, Wormer P.E.S., Żuchowski P.S., SAPT2008: An Ab Initio Program for Many-Body Symmetry-Adapted Perturbation Theory Calculations of Intermolecular Interaction Energies. Sequential and Parallei Versions. 2009. User's Guide, Revision SAPT2008.2Aakeröy Ch.B, Beatty A.M.,. Lorimer K.R, Charge-assisted hydrogen bonds and halogen-halogen interactions in organic salts: Benzylammonium benzoates and pentafluorobenzoates, "Structural Chemistry" 1999, nr 10, s. 229-242.Arunan E., Desiraju G.R., Klein R.A., Sadlej J., Scheiner S., Alkorta I., Clary D.C., Crabtree R.H., Dannenberg J.J., Hobza P. , Kjaergaard H.G.,. Legon A.C, Mennucci B., Nesbitt D.J., Defining the hydrogen bond: An account (lUPAC Technical Report), "Pure and Applied Chemistry" 2011, 83, 1619-1636.Bader R.F. W, A Model for the Hydrogen Bond and Proton Transfer Reactions, "Canadian Journal of Chemistry" 1964, nr 42, s. 1822- 1834.Bankiewicz B., Matczak P. , Palusiak M., , Electron Density Characteristics in Bond Critical Point (QTAIM) versus Interaction Energy Components (SAPT): The Case of Charge-Assisted Hydrogen Bonding, "Journal of Physical Chemistry A" 2012, nr 116, s. 452-459.Bankiewicz B., Palusiak M., Does electron density in bond critical point reflect the formaI charge distribution in H-bridges ? The case of charge-assisted hydrogen bonds (CAHBs) , "Computational & Teoretical Chemistry" 2011, nr 966, s. 113- 119.Bleiholder C., Gleiter R., Werz D.B., Köppel H., Theoretical Investigations on Heteronuclear Chalcogen-Chalcogen Interactions - On the Nature of Weak Bonds Between Chalcogen Centers, "Inorganic chemistry" 2007, nr 46, s. 2249-2260.Boys S.F., Bemardi F. , The calculation of small molecular interactions by the differences of separate total energies. Same procedures with reduced errors, "Molecular Physics" 1970, nr 1 9(4), s. 553-566.Braga D., Draper S.M., Champeil E., Grepioni F. , Inorganic-organometallic crystal synthesis. The role of charge-assisted C-H ... O and C-H ... CI hydrogen bonds in crystalline [(η⁵_C₅H₅)₂Co][H₂PO₄]∙3H₂O and [(η⁶-C₆H₅Me) ₂Cr][Cl], "Journal of Organometallic Chemistry" 1999, nr 573, s. 73-77.Braga D., Grepioni F. , Intermolecular interactions in nonorganic crystal engineering, "Accounts or chemical research" 2000, nr 33, s. 601-608.Braga D., Grepioni F. ,. Desiraju G. R, Crystal Engineering and Organometallic Architecture, "Chemical Reviews". 1998, nr 98, s. 1375-1405 .Braga D., L. Maini, F. Grepioni, A. De Cian, O. Félix, J. Fischer, M.W. Hosseini, Charge-assisted N-H⁽⁺⁾•••O⁽⁻⁾ and O-H•••O⁽⁻⁾ hydrogen bonds control the supramolecular aggregation of ferrocenedicarboxylic acid and bis-amidines, " New Journal of Chemistry" 2000, nr 24, s. 547-553.G. R. Desiraju, Hydrogen Bridges in Crystal Engineering: Interactions without Borders, "Accounts of chemical research" 2002, nr 35, s. 565-573.J.A. Gerlt, M. M. Kreevoy, w.w. CIeland, P.A. Frey, Understanding enzymic catalysis: The importance of short, strong hydrogen bonds, "Chemistry & Biology" 1997, nr 4, s.259-267.Gilli G., Bellucci F. Ferretti V. , . Bertolas V, Evidence for resonance-assisted hydrogen bonding from crystal-structure correlations on the enol form of the β-diketone fragment, "Journal of the American Chemical Society" 1989, nr 111, s. 1023-1028.Gilli P. , Bertolasi V., Ferretti V., Gilli G., Covalent nature of the strong homonuclear hydrogen bond. Study of the O-H--O system by crystal structure correlation methods, "Journal of the American Chemical Society" 1994, nr 116, s. 909-915.Gilli G., Gilli P, Towards an unified hydrogen-bond theory, "Journal of Molecular Structure" 2000, nr 552, s. 1-15.Grabowski S.J., Hydrogen Bonds with π and σ Electrons as the Multicenter Proton Acceptors: High Level ab Initio Calculations, "Journal of Physical Chemistry A" 2007, nr 111, s. 3387-3393 .Grabowski S.J., π-H•••O Hydrogen Bonds: Multicenter Covalent π-H 1nteraction Acts as the Proton-Donating System, "Journal or Physical Chemistry A" 2007, nr 111 , s. 13537- 13543.S.J. Grabowski, Theoretical studies of strong hydrogen bonds, "Annual Reports Section C" 2006, nr 102, s. 131-165.Grabowski S. J., What Is the Covalency of Hydrogen Bonding?, "Chemical Reviews" 2011, nr 111(4), s. 2597-2625.Grabowski S.J., Sokalski W.A., Dyguda E., Leszczynski J., Quantitative Classification of Covalent and Noncovalent H-bonds, "Journal of Physical Chemistry B" 2006, nr 110, s. 6444-6446.Grabowski S.J.,. Sokalski W.A, Leszczynski J., Nature ojX-H+O· · ··6H-Y dihydrogen bonds and X-H " a interaction, " Journal of Physical Chemistry A" 2004, nr 108, s. 5823-5830.Grabowski S.J.,. Sokalski W.A, Leszczynski J., Nature of X-H⁺ᵟ• • ••⁻ᵟH-Y dihydrogen bonds and X-H•••σ a interaction, " Journal of Physical Chemistry A" 2004, nr 108, s. 5823-5830.Grepioni F. , Cojazzi G.,. Draper S.M, Scully N., Braga D., Crystal forms of hexafluorophosphate organometallic salts and the and the Importance of Charge-Assisted C-H---F Hydrogen Bonds, "Organometallics" 1998, nr 17, s. 296-307.Hobza P., Havlas Z., Counterpoise-corrected potential energy surfaces of simple H­-bonded systems, "Theoretical Chemistry Accounts" 1998, nr 99, s. 372-377.Hobza P.,.Selzle H.J,.Schlag E.W, Potential energy surface for the benzene dimer. Results of ab initio CCSD(T) calculations show two nearly isoenergetic structures: T-shaped and parallel-displaced, "Journal of Physical Chemistry" 1996, nr 100, . s. 18790-18794.Hobza P, .Selzle H.J,.Schlag E.W, Structure and Properties of Benzene-Containing Molecular Clusters: Nonempirical ab Initio Calculations and Experiments, "Chemical Reviews" 1994, nr 94, s. 1767-1785 .Jabłoński M., Niekonwencjonalne wiązania wodorowe. Przegląd wyników teoretycznych, "Wiadomości Chemiczne" 2004, nr 58 (7-8), s. 511-53Jeziorski B., Moszyński R., Szalewicz K., Perturbation Theory Approach to Intermolecular Potential Energy Surfaces of van der Waals Complexes, "Chemical Reiews" 1994, nr 94 (7), s. 1887-1930.Koch U., Popelier P., Characterization of C-H-O Hydrogen Bonds on the Basis of the Charge Density, "Journal of Chemical Physics" 1995, nr 99, s. 9747.Lee E.C., Hong B.H., Lee J.Y., Kim J.e., D. Kim,. Kim Y, Tarakeshwar P., Kim K.S., Substituent Effects on the Edge-to-Face Aromatic Interaction, "Journal of the American Chemical Society" 2005, nr 127, s. 4530-4537Liu B., McLean A.D., Accurate calculation of the attractive interaction of two ground state helium atoms, "Journal of Chemical Physics" 1973, nr 59, s. 4557-4558.Nernst W., Verteilung eines Stoes zwischen zwei Lösungsmitteln und zwischen Lösungsmittel und Dampfraum, "Zeitschrift für Physikalische Chemie" 1891, 8, 110-139.Palusiak M., Janowska I., Zakrzewski J.,. Grabowski S.J., Charge-assisted N-H•••I and C-H•••I hydrogen bonding in (1 R, 2S)-1-(ferrocenylmethyl)-2-(methoxymethyl)pyrrolidinium iodide, "Acta Crystallographica Section C" 2005, C6 1, s. m55-m57Parthasarathi R., Subramanian V. , Santhyamurthy N., Hydrogen Bonding without Borders: An Atoms-in-Molecules Perspective, "Journal of Physical Chemistry A" 2006, nr 110, s. 3349-335 1.Pendás A.M.,. Blanco M.A, Francisco E., The nature of the hydrogen bond: A synthesis from the interacting quantum atoms picture, "Journal of Chemical Physics" 2006, 125, 184112-184131 .Perrin C.L,. Nielson J. B, "Strong" Hydrogen Bonds in Chemistry and Biology, "Annual Review of Physical Chemistry" 1997, nr 48, s. 511-544.Rozas L, Alkorta I, Elguero J., Behavior of Ylides Containing N, 0, and C Atoms as Hydrogen Bond Acceptors, "Journal of the American Chemical Society" 2000, nr 122, s. 11154-11161.Simon S., Duran M.,. Dannenberg J.J, How does basis set superposition error change the potential surfaces for hydrogen-bonded dimmers, "Journal of Chemical Physics" 1996, nr 105(24) , s. 11024-11031Sobczyk L., Grabowski S. J., Krygowski T. M., Interrelation between H-bond and Pi-electron delocalization. "Chemical Reviews" 2005, nr 105, s. 3513-3560.Suttor D.J., Evidence for the existence of C-H•••O hydrogen bonds in crystals, "Journal of the Chemical Society (Resumed)" 1963, s. 1105-1110.Taylor R., Kennard O., Crystallographic evidence for the existence of C-H•••O, C-H•••N and C-H•••Cl hydrogen bonds, "Journal of the American Chemical Society" 1982, 104, 5063-5070.Thanthiriwatte K.S., Hohenstein E.G., Burns L.A., Sherrill C.D., Assessment of the Performance of DFT and DFT-D Methods for Describing Distance Dependence of Hydrogen-Bonded Interaction, "Journal of Chemical Theory and Computation" 2011, nr 7, s. 88-96.Wu J., Zhang J., Wang Z., Cao W. , Theoretical investigations of the nature of interaction of ClF with HF, H₂0, and NH₃, " Journal of Chemical Theory and Computation" 2007, nr 3, s. 95-102.426

Corrosion behaviour of boiler tube materials during combustion of fuels containing Zn and Pb

Många förbränningsanläggningar som bränner utmanande bränslen såsom restfraktioner och avfall råkar ut för problem med ökad korrosion på överhettare och/eller vattenväggar pga. komponenter i bränslena som är korrosiva. För att minimera problemen i avfallseldade pannor hålls ångparametrarna på en relativt låg nivå, vilket drastiskt minskar energiproduktionen. Beläggningarna i avfallseldade pannor består till största delen av element som är förknippade med högtemperaturkorrosion: Cl, S, alkalimetaller, främst K och Na, och tungmetaller som Pb och Zn, och det finns också indikationer av Br-förekomst. Det låga ångtrycket i avfallseldade pannor påverkar också stålrörens temperatur i pannväggarna i eldstaden. I dagens läge hålls temperaturen normalt vid 300-400 °C. Alkalikloridorsakad (KCl, NaCl) högtemperaturkorrosion har inte rapporterats vara relevant vid såpass låga temperaturer, men närvaro av Zn- och Pb-komponenter i beläggningarna har påvisats förorsaka ökad korrosion redan vid 300-400 °C. Vid förbränning kan Zn och Pb reagera med S och Cl och bilda klorider och sulfater i rökgaserna. Dessa tungmetallföreningar är speciellt problematiska pga. de bildar lågsmältande saltblandningar. Dessa lågsmältande gasformiga eller fasta föreningar följer rökgasen och kan sedan fastna eller kondensera på kallare ytor på pannväggar eller överhettare för att sedan bilda aggressiva beläggningar. Tungmetallrika (Pb, Zn) klorider och sulfater ökar risken för korrosion, och effekten förstärks ytterligare vid närvaro av smälta. Motivet med den här studien var att få en bättre insikt i högtemperaturkorrosion förorsakad av Zn och Pb, samt att undersöka och prediktera beteendet och motståndskraften hos några stålkvaliteter som används i överhettare och pannväggar i tungmetallrika förhållanden och höga materialtemperaturer. Omfattande laboratorie-, småskale- och fullskaletest utfördes. Resultaten kan direkt utnyttjas i praktiska applikationer, t.ex. vid materialval, eller vid utveckling av korrosionsmotverkande verktyg för att hitta initierande faktorer och förstå deras effekt på högtemperaturkorrosion.Polttoon perustuvassa sähköntuotannossa polttoaineen energia pyritään muuntamaan sähköenergiaksi. Poltossa vapautuvalla lämpöenergialla tuotetaan tulistettua höyryä. Höyry johdetaan turbiiniin, johon kytketty generaattori muuntaa mekaanista energiaa sähköksi. Niin kutsutut haastavat polttoaineet, kuten esimerkiksi jäte ja jäteperäiset polttoaineet, voivat aiheuttaa höyrykattilan tulistinputkien hajoamista ja/tai seinäputkien korroosiota Korroosio-ongelmien välttämiseksi tulistetun höyryn lämpötila pidetään suhteellisen alhaisena, mikä alentaa merkittävästi sähköntuotannon hyötysuhdetta. Jätettä ja jäteperäisiä polttoaineita käyttävien kattiloiden tuhkakerrostumien sisältämät kloori (Cl), rikki (S) ja bromi (Br), alkalimetallit kalium (K) ja natrium (Na), sekä raskasmetallit sinkki (Zn) ja lyijy (Pb) on liitetty korkean lämpötilan korroosioon. Jätettä polttavien kattiloiden seinäputkien lämpötila on yleensä 300-400 °C. Alkaliklorideista (KCl, NaCl) johtuvaa korkean lämpötilan korroosiota ei yleensä esiinny näissä lämpötiloissa. Sen sijaan sinkkiä ja lyijyä sisältävien kerrostumien on havaittu aiheuttaneen korroosiota. Sinkki ja lyijy voivat poltossa reagoida rikin ja kloorin kanssa, muodostaen savukaasuun klorideja ja sulfaatteja. Nämä raskasmetalliyhdisteet ovat korroosion kannalta erityisen merkityksellisiä, koska ne muodostavat alhaisissa lämpötiloissa sulavia suolaseoksia. Kerrostuman osittainenkin sulaminen lisää korroosioriskiä. Tämän työn tavoitteena oli sinkin ja lyijyn aiheuttaman korkean lämpötilan korroosion mekanismien parempi ymmärrys, sekä joidenkin höyrykattiloissa käytettyjen seinäputki- ja tulistinmateriaalien käyttäytymisen ja korroosionkeston arviointi kyseessä olevien raskasmetallien vaikutuksen alaisena, myös korkeissa lämpötiloissa. Tavoitteeseen pääsemiseksi suoritettiin laboratorio-, penkki-, ja teollisuuskokoluokan kokeita. Kokeiden tuloksia voidaan hyödyntää suoraan käytännössä, esimerkiksi tehtäessä materiaalivalintoja sekä kehitettäessä korroosionkeston parantamiseen tähtääviä työkaluja tunnistamalla korroosiota käynnistäviä tekijöitä ja ymmärtämällä niiden vaikutuksia.Many power plants burning challenging fuels such as waste-derived fuels experience failures of the superheaters and/or increased waterwall corrosion due to aggressive fuel components already at low temperatures. To minimize corrosion problems in waste-fired boilers, the steam temperature is currently kept at a relatively low level which drastically limits power production efficiency. The elements found in deposits of waste and waste-derived fuels burning boilers that are most frequently associated with high-temperature corrosion are: Cl, S, and there are also indications of Br; alkali metals, mainly K and Na, and heavy metals such as Pb and Zn. The low steam pressure and temperature in waste-fired boilers also influence the temperature of the waterwall steel which is nowadays kept in the range of 300 °C - 400 °C. Alkali chloride (KCl, NaCl) induced high-temperature corrosion has not been reported to be particularly relevant at such low material temperatures, but the presence of Zn and Pb compounds in the deposits have been found to induce corrosion already in the 300 °C - 400 °C temperature range. Upon combustion, Zn and Pb may react with Cl and S to form chlorides and sulphates in the flue gases. These specific heavy metal compounds are of special concern due to the formation of low melting salt mixtures. These low melting, gaseous or solid compounds are entrained in the flue gases and may stick or condense on colder surfaces of furnace walls and superheaters when passing the convective parts of the boiler, thereby forming an aggressive deposit. A deposit rich in heavy metal (Zn, Pb) chlorides and sulphates increases the risk for corrosion which can be additionally enhanced by the presence of a molten phase. The objective of this study was to obtain better insight into high-temperature corrosion induced by Zn and Pb and to estimate the behaviour and resistance of some boiler superheater and waterwall materials in environments rich in those heavy metals, including at increased temperatures of materials. Therefore, extensive laboratory, bench-scale and full-scale tests were carried out. The results from these tests may be directly made use of in practical applications, for example for screening steels from the materials selection, as well as in the development of corrosion preventing tools by finding corrosion initiating triggers and understanding their effect on high-temperature corrosion. The laboratory study covered steel exposure tests with pure ZnCl2, ZnO, PbCl2 and PbO as well as with a number of salt mixtures: ZnCl2-K2SO4, PbCl2-K2SO4, PbCl2-KCl and PbCl2- ZnCl2-KCl. It was shown that pure PbCl2 starts to be aggressive to the low-alloy steel (10CrMo9-10) and also to the stainless steels (AISI 347) already at temperatures around 350 °C, below the melting temperature of PbCl2 which is 501 °C. The protective Cr2O3 on the AISI 347 was destroyed due to PbCrO4 formation. The exposures to ZnCl2 showed an increased oxide layer growth on the 10CrMo9-10 already at 350 °C, but negligible oxide layer growth on the AISI 347 up to 450 °C. Above 350 °C, the fast evaporation of ZnCl2 suppressed the growth of the oxide layer. The tests with ZnCl2- and PbCl2-containing mixtures (ZnCl2-K2SO4, PbCl2-K2SO4, PbCl2-KCl and PbCl2-ZnCl2-KCl) showed that the ZnCl2-containing mixture (PbCl2-ZnCl2-KCl) was more aggressive and active at lower temperatures than the PbCl2-KCl mixture. It suggests, therefore, that ZnCl2 is more likely to cause problems at lower material temperatures, while PbCl2 is more stable and is expected to be problematic at both waterwall and superheater temperatures. At 400 °C, the highest corrosion rates on both test materials were observed when both PbCl2 and ZnCl2 were present in the salt. The PbCl2-ZnCl2-KCl mixture contained the highest fraction of melt out of all tested salt mixtures but the corrosiveness of this mixture was not the highest at all test temperatures. Thus, the amount of melt does not necessary decide the extent of corrosion. At 500 °C and above the corrosion caused by all three mixtures containing PbCl2 was significant and both steels were damaged to a similar degree. The results from the tests with the mixtures containing 5 wt-% PbCl2 were similar to the results from the tests with pure PbCl2 showing its extremely corrosive character. ZnO was shown not to be corrosive to the low-alloy steel (10CrMo9-10) and nor to the stainless steel (AISI 347) at 550 °C. The oxide layer thickness was comparable to the test with no salt present. However, tests with PbO at 550 °C caused a noticeable oxide layer growth on 10CrMo9-10 and fairly low on AISI 347. To better understand the fate of Zn and its effect on high-temperature corrosion specifically in waste-wood fired fluidized bed boilers, high-temperature corrosion/deposit probe tests were performed in a 30 kWth bubbling fluidized-bed reactor by firing wood pellets doped with ZnCl2 to simulate waste wood. Specific issues of interest in this study included the general impact of firing waste wood containing higher amounts of Zn and Cl and the evaluation of the role of ZnCl2 in high-temperature corrosion. The tests showed that the presence of ZnCl2 had a clear impact on high-temperature corrosion of low-alloy steel. When compared to the combustion of pure wood pellet, corrosion increased at temperatures above 450 °C (probe cooling temperature). The K2ZnCl4 which was found in the deposit was concluded to be the main corrosive agent. During the planning stage of further experiments there were strong indications of bromide induced high-temperature corrosion of the waterwalls. In consequence, a measurement campaign in a BFB co-combusting SRF was performed to determine the occurrence of corrosive Cl-, Br-, Zn- and Pb-compounds in the fuel, in the furnace vapours and in the waterwall deposits. The relative corrosiveness of chlorides and bromides was further established by means of laboratory experiments. A ZnBr2-K2SO4 salt mixture was tested and compared with a corresponding ZnCl2-K2SO4 salt mixture. The mixture with ZnBr2 was found to be more aggressive at 400 °C in oxidising conditions than the corresponding mixture with ZnCl2. A measurement campaign showed that vapours in the furnace were enriched with Cl and small amounts of Br, Zn and Pb. The chemical thermodynamic calculations indicated that possible forms of those compounds at the waterwall deposit temperatures (400 °C) were Na-, K-bromides and chlorides and Zn- and Pb-sulphides or sulphates in reducing and oxidizing conditions, respectively. The thermodynamic calculations correlated with the deposit analysis

The Use of Convection-Enhanced Delivery with Liposomal Toxins in Neurooncology

Liposomes have long been effective delivery vehicles for transport of toxins to peripheral cancers. The combination of convection-enhanced delivery (CED) with liposomal toxins was originally proposed to circumvent the limited delivery of intravascular liposomes to the central nervous system (CNS) due to the blood-brain-barrier (BBB). CED offers markedly improved distribution of infused therapeutics within the CNS compared to direct injection or via drug eluting polymers, both of which depend on diffusion for parenchymal distribution. This review examines the basis for improved delivery of liposomal toxins via CED within the CNS, and discusses preclinical and clinical experience with these therapeutic techniques. How CED and liposomal technologies may influence future neurooncologic treatments are also considered

Integrated management of ash from industrial and domestic combustion : a new sustainable approach for reducing greenhouse gas emissions from energy conversion

This work supports, for the first time, the integrated management of waste materials arising from industrial processes (fly ash from municipal solid waste incineration and coal fly ash), agriculture (rice husk ash), and domestic activities (ash from wood biomass burning in domestic stoves). The main novelty of the paper is the reuse of wood pellet ash, an underestimated environmental problem, by the application of a new technology (COSMOS-RICE) that already involves the reuse of fly ashes from industrial and agricultural origins. The reaction mechanism involves carbonation: this occurs at room temperature and promotes permanent carbon dioxide sequestration. The obtained samples were characterized using XRD and TGA (coupled with mass spectroscopy). This allowed quantification of the mass loss attributed to different calcium carbonate phases. In particular, samples stabilized using wood pellet ash show a weight loss, attributed to the decomposition of carbonates greater than 20%. In view of these results, it is possible to conclude that there are several environmental benefits from wood pellet ash reuse in this way. In particular, using this technology, it is shown that for wood pellet biomass the carbon dioxide conversion can be considered negative