Extraction of colour inkjet printing inks from printouts for forensic purpose

The ability to differentiate between inkjet printing inks is of great interest in document examination. The aim of this work was to develop a procedure for effective ink extraction so that the ink could be reliably analyzed by capillary electrophoresis. Conditions such as type and composition of extracting mixtures, as well as duration of extraction and sonication procedures were taken into consideration. A set of different agents was used to extract inks of inkjet printers produced by Hewlett-Packard, Canon, Brother, Epson and Lexmark. Extraction efficiency was examined visually and then by means of UV/Vis spectrometry. It was ascertained that the most promising extracting agents are mixtures of borate buffer with SDS and with acetonitrile, or alternatively with methanol, which are both suitable background electrolytes for further CE analysis. However, in some exceptional cases, highly efficient extraction was achieved by a mixture of DMF, DMSO, EtOH and MEE with water

Niemodlitewne modlitwy Krasińskiego

The subject of Krasiński’s Non-prayer Prayer Poems is a number of his works which although fit the structural characteristics of the genre, are not in fact prayers. There are some other reasons for using this literary forms.. For instance, Daj jej o Panie… (Give Her Oh Lord...) is an instruction for the beloved one on how to behave in difficult life situations, and on the other hand a treatise on philosophy and religion. Another example is Boże, wysłuchaj modlitwę moją serdeczną… (God, Hear my Cordial Prayer…) which is a classic erotic poem addressed to Joanna Bobrowa. O Boże, błogosław tym… (Dear God bless those…) is yet another example of this phenomenon since it is a courtesy gesture towards the Ankwicz family and at the same time a personal and unlikely fantasy about the end of the world. The article reveals both Krasiński’s genealogical awareness of the prayer poem form as well as his religious attitude.Przedmiotem pracy Niemodlitewne modlitwy Krasińskiego jest grupa utworów poety które, mimo że spełniają cechy strukturalne tego gatunku, w rzeczywistości modlitwami nie są. Mamy tu bowiem do czynienia z użyciem tej formy literackiej do innych celów. I tak np. Daj jej o Panie… to z jednej strony swoisty instruktarz dla ukochanej, jak postępować w trudnych biograficznie sytuacjach, a z drugiej strony traktat filozoficzno-religijny. Boże, wysłuchaj modlitwę moją serdeczną… to z kolei klasyczny erotyk kierowany do Joanny Bobrowej. O Boże, błogosław tym… to natomiast swego rodzaju gest kurtuazyjnej wdzięczności wobec rodziny Ankwiczów, połączony z osobistą i dość oryginalną fantazją o końcu świata. Artykuł ten ujawnia zarówno świadomość genologiczną Krasińskiego w zakresie modlitwy poetyckiej, jak też jego postawę religijną

Oxide Free Wire Arc Sprayed Coatings—An Avenue to Enhanced Adhesive Tensile Strength

Conventionally, thermal spraying processes are almost exclusively carried out in an air atmosphere. This results in oxidation of the particles upon thermal spraying, and thus, the interfaces of the splats within the coating are oxidized as well. Hence, a full material bond strength cannot be established. To overcome this issue, a mixture of monosilane and nitrogen was employed in the present study as the atomising and environment gas. With this approach, an oxygen partial pressure corresponding to an extreme-high vacuum was established in the environment and oxide-free coatings could be realized. It is shown that the oxide-free particles have an improved substrate wetting behaviour, which drastically increases the adhesive tensile strength of the wire arc sprayed copper coatings. Moreover, the altered deposition conditions also led to a significant reduction of the coating porosity

Gas Phase Reaction of Silane with Water at Different Temperatures and Supported by Plasma

The interaction of silane and water is discussed controversially in literature: some authors suggest monosilane and water react kinetically and sufficiently fast enough to remove water, while others state the reaction occurs only at elevated temperatures. This question is of technological interest for the removal of unavoidable water residues in Ar gases. Thermodynamic calculations show that virtually complete removal of water is expected with superstoichiometric silane addition. However, mass spectrometric and infrared spectroscopic experiments give evidence that the addition of monosilane to such an Ar gas at room temperature is unable to remove residual water, which disagrees with some current hypotheses in the literature. This holds even for very high SiH4 concentrations up to 2 vol.-%. Silane reacts with water above temperatures of 555 °C, initiated by the thermal decomposition of silane. A cold dielectric barrier discharge-plasma used for silane and water dissociation enhances reactivity similar to elevated temperatures. Fourier-transformed infrared spectroscopy points toward silanol generation at temperatures between 400 and 550 °C, while quadrupole mass spectrometry indicates the creation of SiOH+, SiHOH+, SiH2OH+, and SiH3OH+. Cold plasmas generate smaller amounts of SiOH+, SiHOH+, and SiH2OH+ compared to elevated temperatures. Reaction products are hydrogen and nanoscaled particles of non-stoichiometric silicon oxides. The silicon-oxide particles produced differ in elemental composition and shape depending on the prevailing water content during decomposition: SiOx generated with residual water appears with relatively smooth surfaces, while the addition of water supports the formation of significantly rougher particle surfaces. Higher initial water contents correlate with higher oxygen contents of the particles

Influence of an oxygen-free atmosphere on laser beam brazing of aluminium with prior surface deoxidation by pulsed laser radiation

Aluminium alloys, like AlMgSi1 and AlMg3, cannot be joined in industrial processes by laser beam brazing without the use of fluxes due to their resistant oxide layer. The aim of this study is to dispense with the use of flux. For the investigations, an oxygen-free atmosphere was created by using the highly reactive gas monosilane and thus achieving O2 partial pressures of 10-18 mbar. After removal of the oxides by a laser source with 1064 nm wavelength, pulse energies of max. 0.3 µJ and pulse durations of 45 ns, reoxidation is prevented by the oxygen-free atmosphere, so that brazing is carried out on an oxide-free material surface. The bead on plate seams show a materially bonded brazed joint in cross-section. Reference experiments without monosilane either show no wetting or an increased melting of base material. The influence of laser beam power for brazing, pulse energy for deoxidation and wire feed was investigated

Young’s Modulus and Residual Stresses of Oxide-Free Wire Arc Sprayed Copper Coatings

Conventional thermal spraying processes are almost exclusively carried out in an air atmosphere, resulting in the oxidation of the particle surfaces and interfaces within the coating and between the substrate and coating. Furthermore, the initial process of surface activation conventionally takes place in an air atmosphere, preventing an oxide-free interfacial transition. Consequently, the application of spraying materials with high oxygen affinity represents a major challenge. To overcome these issues, the present study utilized silane-doped inert gases to create an environment in which the oxygen concentration was equivalent to the residual oxygen content in an extreme high vacuum. By transferring the corundum blasting and coating process (wire arc spraying) to this environment, materials with a high oxygen affinity can be applied without oxidation occurring. For industrial use, this is an interesting prospect, e.g., for repair coatings, as the homogeneity of the composite is improved by a non-oxidized coating. Using the example of arc-sprayed copper coatings, the microstructure and mechanical properties of the coatings were analysed. The results showed that the oxide-free, wire arc sprayed copper coatings exhibited an improved wetting behaviour resulting in a significant reduction of the coating porosity. Moreover, the improved wetting behaviour and led to an increase in the bonding rate and apparent Young’s modulus. Contrary to expectations, the residual stresses decrease although relaxation mechanisms should be inhibited, and possible reasons for this are discussed in the paper

Potentiale und Eigenschaften des Lichtbogenspritzens in silandotierten Inertgasen

Neben den funktionalen Eigenschaften ist die Haftfestigkeit eines der wichtigsten Kriterien für den industriellen Einsatz von thermisch gespritzten Schichten. Da konventionelle thermische Spritzverfahren fast ausschließlich an Luftatmosphäre durchgeführt werden, führt dies zur Oxidation der Spritzpartikel und der Grenzflächen innerhalb der aufgespritzten Schichten. Konventionelle thermisch gespritzte metallische und metallkeramische Schichten weisen daher eine heterogene Schichtmorphologie mit interlamellaren Oxidsäumen sowie ein eingeschränktes Benetzungsverhalten am Schicht-Substrat Interface auf. Dies hat einen entscheidenden Einfluss auf die Bindungsmechanismen thermisch gespritzter Schichten. Ziel dieser Arbeit ist es, das Potential von thermischen Spritzprozessen in einem Gemisch aus Silan und einem Inertgas bei Umgebungsdruck als Alternative zu den bekannten Vakuum- und Kaltgasspritzverfahren darzustellen. Am Beispiel von lichtbogengespritzten Schichten wird gezeigt, dass der resultierende extrem niedrige Sauerstoffpartialdruck in der silandotierten Prozessatmosphäre die Oxidation während des Beschichtungsprozesses unterdrückt. Dies führt zu Schichten mit reduzierter Porosität und deutlich verbesserten Eigenschaften. Ferner werden so Bedingungen geschaffen, die die Applikation von hochsauerstoffaffinen Werkstoffen mit dem Lichtbogenspritzen erst ermöglichen

Sukces w terapii jąkania - czym jest i jak go osiągnąć - opinie „podwójnych ekspertów”

Jąkanie jest zjawiskiem wielowymiarowym, definiowanym na wielu płaszczyznach. W związku z tym istnieją różne podejścia do terapii tego zaburzenia, a zatem na różne sposoby można też określać zarówno cele interwencji terapeutycznej, jak to, co należy uznawać za sukces w terapii. Pomysłodawczynie tego artykułu-wywiadu – Katarzyna Węsierska i Aleksandra Boroń zaprosiły do dyskusji na ten temat osoby, które wystąpiły w roli „podwójnych ekspertów”. Gospodynie tego wywiadu za takie osoby uznały tych, którzy na co dzień mają osobiste doświadczenia z jąkaniem, a którzy jednocześnie – zawodowo lub społecznie – angażują się w działalność pomocową na rzecz osób jąkających się. Do udziału w panelu dyskusyjnym zaproszone zostały więc osoby, które reprezentują środowisko profesjonalistów – są terapeutami (logopedami, psychologami, badaczami na gruncie logopedii) lub są społecznikami na tym polu – aktywnymi działaczami ruchu samopomocowego, liderami grup wsparcia. W dyskusji udział wzięli rozmówcy z Polski: Grzegorz Chmielewski (psycholog i logopeda), Zdzisław Gładosz (lider polskiego ruchu samopomocy dla osób jąkających się), Lucyna Jankowska-Szafarska (psycholog kliniczny i liderka grupy terapeutyczno- samopomocowej) oraz goście z zagranicy: z Izraela – Benny Ravid (lider izraelskiego ruchu samopomocy), z Niemiec – Tobias Haase (aktywny działacz niemieckiego ruchu samopomocy), z USA – profesorowie Paul Blanchet i Kenneth O. St. Louis (logopedzi, badacze i liderzy lokalnych grup samopomocowych), a także z Wielkiej Brytanii – Rachel Everard (logopedka i liderka brytyjskiego ruchu samopomocy). Tematyka rozważań podjętych w rozmowach z tymi „podwójnymi ekspertami” koncentrowała się wokół takich zagadnień, jak percepcja sukcesu w terapii jąkania, określenie celów skutecznej terapii, udzielenie wskazówek/porad rodzicom dzieci z tym problemem w mowie, osobom dorosłym poszukującym pomocy i młodym logopedom, a także określenie roli grup samopomocowych w procesie terapii jąkania