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1

The effect of anodic polarization of 304 stainless steel in choline chloride-based DES solvent on its surface morphology and corrosion resistance

Marczewski Marek, Tylus Włodzimierz, Winiarska Juliusz

Ochrona przed Korozją

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2024

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nr 4

96--105

EN

AISI 304 alloy steel was polarized anodically in a deep eutectic solvent based on choline chloride and oxalic acid (1 : 1 molar ratio) at the temperature range of 25–75°C and the current density range of 2.5–45 mA cm−2. No improvement in visual parameters (gloss) was observed with increasing temperature. That was due to the formation of numerous pits on the surface as evidenced by SEM microscopy. AFM showed at lower temperatures the evenly distributed shallow pits, while at higher temperatures – less numerous but larger ones. XPS and ICP-AES analysis showed that the anodic polarization process increased the content of oxidized chromium on the surface and indicated high degree of iron leaching from the material. Morphology of this passive layer, which thickness was calculated to 3.3 nm, was characterized by uniform mixture of Cr(III) oxide and hydroxide. In contrast to chemically etched steel, polarization in DES produced surface layer enriched with Cr2O3 (56% instead of 28% total share) with lower share of Cr(OH)3 (41% instead of 70% total share). Anodic polarization process in proposed DES was responsible for a slight increase in corrosion resistance of 304 steel.

PL

Stal stopową AISI 304 poddano polaryzacji anodowej w rozpuszczalniku eutektycznym złożonym z chlorku choliny i kwasu szczawiowego (1 : 1 molowo) w temperaturze 25–75°C i przy gęstości prądu 2,5– 45 mA cm−2. Nie zaobserwowano poprawy połysku wraz ze wzrostem temperatury procesu ze względu na powstanie licznych wżerów na powierzchni, widocznych za pomocą mikroskopii SEM. Analiza AFM wykazała, że w niższych temperaturach wżery są płytkie i równomiernie rozmieszczone, a w wyższych są większe i mniej liczne. Analizy XPS i ICP-AES ujawniły, że na skutek polaryzacji anodowej wzrasta ilość utlenionego chromu w powierzchni stali, czemu towarzyszy nadmierne roztwarzanie żelaza ze stopu. Morfologia wytworzonej warstwy pasywnej, o grubości około 3,3 nm, to jednorodna mieszanina tlenku i wodorotlenku Cr(III). W porównaniu z trawioną chemicznie stalą polaryzacja anodowa w DES skutkuje wytworzeniem warstwy powierzchniowej wzbogaconej w Cr2O3 (56% zamiast 28% zawartości) i z mniejszym udziałem Cr(OH)3 (41% zamiast 70%). Proces polaryzacji anodowej stali 304 w zaproponowanym DES przyczynił się do poprawy odporności na korozję.

2

Possibility of obtaining lanthanum doped nickel coatings from baths based on deep eutectic solvents

Niciejewska Anna, Tylus Włodzimierz, Marczewski Marek, Winiarska Katarzyna, Szczygieł Bogdan, Winiarski Juliusz

Ochrona przed Korozją

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2022

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nr 11

344--349

EN

Lanthanum-doped nickel coatings were obtained from the bath based on a deep eutectic solvent: choline chloride and propylene glycol, mixed in a molar ratio of 1 : 2, and 0.2 mol dm−3 NiCl2 ∙ 6H2O and 0.5 mol dm−3 LaCl2 ∙ xH2O. The morphology, topography and chemical composition were examined. The lanthanum content in the coating was determined to be 1.7 wt. % using the ICP-MS method. Lanthanum on the surface was mainly in the form of lanthanum carbonate. The obtained coating was exposed to a 7-day exposure in 0.05 mol dm−3 NaCl solution. The coating showed the highest corrosion resistance (Rp ~ 30 kΩ cm2) after 15 hours of exposure to the NaCl solution.

PL

Powłoki niklowe domieszkowane lantanem zostały otrzymane z kąpieli na bazie rozpuszczalnika eutektycznego chlorku choliny i glikolu propylenowego zmieszanych w proporcjach molowych 1 : 2 oraz 0,2 mol dm−3 NiCl2 ∙ 6H2O i 0,5 mol dm−3 LaCl2 ∙ xH2O. Zbadano morfologię, topografię oraz skład chemiczny. Zawartość lantanu w powłoce została określona na 1,7% mas. techniką ICP-MS. Na powierzchni powłoki lantan występował głównie w postaci węglanu lantanu. Otrzymana powłoka została poddana 7-dniowej ekspozycji w 0,05 mol dm−3 roztworze NaCl. Największą odporność na korozję powłoki stwierdzono po 15-godzinnej ekspozycji w roztworze NaCl.

3

A multi-analytical approach for the analysis of cation distribution in a aluminoceladonite structure

Kądziołka-Gaweł Mariola, Dulski Mateusz, Czaja Maria, Krzykawski Tomasz, Szubka Magdalena

Acta Geologica Polonica

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2022

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Vol. 72, no. 3

353--368

EN

In this paper cation arrangement in two samples of aluminoceladonite, emerald green and dark-green were studied by Mössbauer, Raman and X-ray photoelectron spectroscopies. The X-ray photoelectron spectroscopy (XPS) spectra obtained in the region of the Si2p, Al2p, Fe2p, K2p, and O1s core levels provided information, for the first time highlighting a route to identify the position of Si, Al, K, and Fe cations in a structure of layered silicates. The XPS analysis showed the presence of Al in tetrahedral and octahedral coordination while the K2p line indicated the possibility of K+ substitution by other cations in interlayer sites. Mössbauer spectroscopy provided information about crystal chemistry with respect to the local electronic and geometric environment around the Fe atom and to distortions of the polyhedra. It turned out that iron was located mostly in the cis-octahedra position wherein about 75% of iron appeared in the form of Fe3+. The most preferred cation combinations around Fe corresponded to 3Fe3+ ions and MgFe2+Fe3+/2MgFe3+. Raman spectroscopy illustrated aluminium substitution in silicon and iron positions wherein the concentration of the aluminium determined the degree of structural distortion within the layered system. These isomorphic substitutions implied a typical band arrangement in the hydroxyl region, which has not been observed in celadonites so far.

4

Acrylic polyurethane coatings durability under outdoor weathering in an industrial area

Białomazur Magdalena, Jasińska Izabella, Kowalczyk Krzysztof, Musik Marlena, Pasierbiewicz Kamil, Wróbel Rafał J.

Polimery

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2021

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T. 66, nr 10

503--517

EN

In this work, weathering performance and durability of a commercial automotive acrylic polyurethane topcoat samples exposed at a natural testing station in an industrial atmosphere (Police, Poland) were studied. After a 16-month outdoor aging process, surface morphology and general appearance of the clearcoat were investigated by means of optical and scanning electron microscopes, an optical profilometer and by a glossmeter. For further investigation of the samples surfaces chemistry X-ray photo-electron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) were utilized. Test results showed that the outdoor exposure changed the appearance of the acrylic polyurethane topcoat surface because protuberant spots of various sizes were observed. Quantitative profilometric analysis indicated an apparent increase of surfaces roughness, however, no signs of chemical degradation of the studied topcoat were revealed by XPS and FTIR analyses. Finally, it was apparent that the surface protuberances observed after the ageing test resulted by atmospheric deposits consisting mainly of oxygen, calcium, phosphorus, iron, and silicon compounds and elemental carbon. Additionally, it was revealed that a detailed cleaning process of the clearcoat surfaces may remove the detected contaminants.

PL

W niniejszej pracy zbadano trwałość próbek komercyjnej akrylowo-poliuretanowej nawierzchniowej powłoki samochodowej w trakcie ich ekspozycji w atmosferze przemysłowej zakładów chemicznych (Police, Polska). Morfologię powierzchni i ogólny wygląd powłok lakierowych (po 16 miesiącach testu) zbadano za pomocą mikroskopu optycznego i skaningowego mikroskopu elektronowego, profilometru optycznego oraz połyskomierza. Do badań składu i struktury chemicznej powierzchni wymalowań wykorzystano rentgenowską spektroskopię fotoelektronów (XPS) oraz spektroskopię w podczerwieni z transformacją Fouriera (FTIR). Ekspozycja w atmosferze przemysłowej zmieniła wygląd powierzchni powłok gdyż zaobserwowano wypukłe plamy o różnej wielkości. Dodatkowo, ilościowa analiza profilometryczna wykazała wyraźny wzrost chropowatości powierzchni, chociaż wyniki badań metodami XPS i FTIR nie wykazały żadnych oznak chemicznej degradacji testowanych próbek. Ostatecznie okazało się, że wypukłości obserwowane na powierzchniach starzonych powłok były osadami atmosferycznymi składającymi się głównie ze związków tlenu, wapnia, fosforu, żelaza, krzemu oraz węgla. Dodatkowo wykazano, że dokładne umycie powierzchni powłok powoduje usunięcie wspomnianych zanieczyszczeń.

5

Analysis of the Possibility of Using Extruded Polystyrene (XPS) Wastes to Make Lightweight Cement Composites

Zegardło Bartosz, Kobyliński Krzysztof

Journal of Ecological Engineering

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2021

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Vol. 22, nr 7

123--131

EN

The paper presents the problem of utilization of extruded polystyrene wastes by its secondary use as filler for cement composites. Wastes were obtained from a company carrying out thermomodernisation works in the form of shapeless, undersized construction waste. The remains of the boards were crushed and separated using the sieve method. The basic technical parameters of thus prepared waste were assessed in terms of its use as a lightweight aggregate for concrete. The technical properties of wastes were compared with those of traditional aggregates used in concrete composites. During the research work, the samples of a cement composite were produced in which the waste served as a filler. In successive test series, the waste constituted 30, 50 and 100% of the aggregate substitution in the mix. Comparative samples without waste were also made. The results showed that the waste could potentially be used to produce lightweight cement composites with high strength parameters.

6

Hydrophilization of Polyester Textiles by Nonthermal Plasma

Azeem Musaddaq, Javed Asif, Morikawa Hideaki, Noman Muhammad Tayyab, Khan Muhammad Qamar, Shahid Muhammad, Wiener Jakub

Autex Research Journal

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2021

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Vol. 21, no. 2

142--149

EN

Polyester is a popular class of material used in material engineering. With its 0.4% moisture regain, polyethylene terephthalate (PET) is classified as highly hydrophobic, which originates from its lack of polar groups on its backbone. This study used a parallel-plate nonthermal plasma dielectric barrier discharge system operating at medium pressure in dry air and nitrogen (N2) to alter the surface properties of PET fabrics to increase their hydrophilic capabilities. Water contact angle, atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS) were utilized to analyze any effect from the plasma treatment. The wettability analysis revealed a reduction in the contact angle of more than 80% within 5 min for both discharges. Scanning electron microscopy analysis showed no microscopic damage to the fiber structure, guaranteeing that the fabrics’ structural integrity was preserved after treatment. AFM analysis showed an increase in the nanometer roughness, which was considered beneficial because it increased the total surface area, further increasing the hydrophilic capacity. XPS analysis revealed a sharp increase in the presence of polar functional groups, indicating that the induced surface changes are mostly chemical in nature. Comparing that of untreated fabrics to treated fabrics, a Increase in water absorption capacity was observed for air-treated and N2-treated fabrics, when these fabrics were used immediately after plasma exposure.

7

Zastosowanie rentgenowskiej spektroskopii fotoelektronów do analizy produktów korozji stopów wapnia

Młynarek Katarzyna, Szyba Dawid, Babilas Rafał, Bajorek Anna

LAB Laboratoria, Aparatura, Badania

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2020

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R. 25, nr 2

30--32, 41

8

XPS (X-Ray Photoelectron Spectroscopy) Study of Removing Iron Ions from Water by Zeolite and Bentonite

Skvarlova Anna, Kanuchova Maria, Kozakova L'ubica, Bakalar Tomas, Oravcova Andrea, Skvarla Jiri

Inżynieria Mineralna

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2020

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no. 1, vol. 2

201--204

EN

Zeolites as a member of family of hydrated aluminosilicate minerals contains alkali and alkaline-earth metals. They are noted for their lability toward ion-exchange and reversible dehydration. Their framework structure encloses interconnected cavities occupied by large metal cations and water molecules. Bentonites are clays generated frequently from the alteration of volcanic ash, consisting predominantly of smectite minerals, usually montmorillonite. They present strong colloidal properties and its volume increases several times when coming into contact with water, creating a gelatinous and viscous fluid. The special properties of bentonite (hydration, swelling, water absorption, viscosity, thixotropy) make it a valuable material for a wide range of uses and applications. The purpose of this paper is to document an ability of a zeolite and bentonite to remove iron ions and various other pollutants from water. The surface analysis of zeolite and bentonite was performed by the very sensitive analytical device – XPS (X–ray photoelectron spectroscopy).

PL

Zeolity należą do rodziny uwodnionych minerałów glinowokrzemianowych, zawierających metale alkaliczne oraz alkaliczno-ziemne. Są zauważane ze względu na ich zdolność wymiany jonowej oraz odwrotnej dehydratacji. Ich struktura zawiera wewnętrznie połączone wgłębienia zajęte przez duże kationy metali oraz cząsteczki wody. Bentonity to iły tworzone często poprzez alterację popiołu wulkanicznego, zawierające głównie minerały smektytu a zazwyczaj montmorillonitu. Wykazują silne właściwości koloidalne a ich objętość wzrasta kilkukrotnie podczas wejścia w kontakt z wodą, tworząc w ten sposób galaretowatą i lepką ciecz. Specjalne właściwości bentonitu (hydratacja, puchnięcie, absorpcja wody, lepkość, tiksotropia) powodują, że jest to cenny materiał dla szerokiej gamy zastosowań. Celem tego artykułu jest udokumentowanie zdolności zeolitów oraz bentonitów do usuwania jonów żelaza oraz różnych innych zanieczyszczeń z wody. Analiza powierzchni zeolitu i bentonitu została wykonana za pomocą bardzo czułego urządzenia analitycznego – XPS (roentgenowska spektroskopia fotoelektronowa).

9

Influence of High-Power Electromagnetic Pulses on the Structural-Chemical and Physicochemical Properties of Rare-Earth Minerals

Chanturiya Valentine A., Bunin Igor Zh., Ryazantseva Maria V.

Inżynieria Mineralna

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2020

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no. 1, vol. 2

179--182

EN

The investigation of the structural-chemical state and sorption properties modification of columbite and eudialite surface under the impact of high-power nanosecond pulses (HPEMP) was performed using XPS and FTIR. It was defined that preliminarily treatment of rare-metal minerals with high-power nanosecond pulses is promising tool for the directional changes in their physicochemical and structural-chemical properties as it was confirmed by the increasing of mineral's sorption activity.

PL

Badanie modyfikacji stanu strukturalno-chemicznego i właściwości sorpcyjnych powierzchni kolumbitu i eudialitu pod wpływem impulsów nanosekundowych o dużej mocy (HPEMP) przeprowadzono za pomocą XPS i FTIR. Ustalono, że wstępna obróbka minerałów metali rzadkich impulsami nanosekundowymi o dużej mocy jest obiecującym narzędziem do kierunkowych zmian ich właściwości fizykochemicznych i strukturalno-chemicznych, co zostało potwierdzone przez zwiększenie aktywności sorpcyjnej minerału.

10

Investigations on soluble starch as the depressant of hematite during flotation separation of apatite

Bai Shaojun, Ding Zhan, Fu Xianyu, Li Chunlong, Lv Chao, Wen Chao

Physicochemical Problems of Mineral Processing

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2019

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Vol. 55, iss. 1

38--48

EN

In this paper, soluble starch was studied as a depressant of hematite during flotation separation of apatite using sodium oleate as a collector. Surface charge measurement, soluble starch adsorptions, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) were used to understand the interaction mechanisms between minerals (hematite and apatite) and soluble starch. The results indicated that chemical interaction between hematite and soluble starch was present, and supported the bonding of hydroxyl, while physical adsorption of soluble starch molecules with apatite occurred. Results of micro-flotation studies suggested that soluble starch was considered as a selective depressant for hematite. The maximum recovery difference between hematite and apatite of 77.5% was obtained with 40 mg/dm3 soluble starch. The flotation experiment results of natural iron ore showed that flotation indexes with 59.73% Fe, iron recovery of 81.5% and 75.68% of dephosphorization ratio were achieved at a soluble starch dosage of 60 mg/dm3. However, a higher dosage of soluble starch addition caused the difficulty for flotation separation of apatite from hematite. Our results provided theoretical basis for the flotation separation of apatite from iron oxide ores.

11

Adsorption behavior and XPS analysis of nonylphenol ethoxylate on low rank coal

You Xiaofang, Ma Chuandong, Li Zhihao, Lyu Xianjun, Li Lin

Physicochemical Problems of Mineral Processing

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2019

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Vol. 55, iss. 3

721--731

EN

In this work, low rank coal was used for the removal of nonylphenol ethoxylate with fifteen ethylene oxide groups (NPEO15) from aqueous solutions at different contact times, temperatures, and initial adsorbent concentrations. The adsorption isotherms showed good fit with the Langmuir equation. Maximum adsorption capacities calculated at 308, 318, and 328 K were 23.64, 29.41, and 35.71 mg g–1, respectively. The changes in the free energy of adsorption (ΔG°), enthalpy (ΔH°), and entropy (ΔS°) were calculated in order to predict the nature of adsorption. The results of the thermodynamic analysis indicated that a spontaneous process took place, driven synergistically by both enthalpy and entropy. The adsorption kinetics of NPEO15 were consistent with a pseudo-second order reaction model. XPS results showed that the oxygen functional groups on the low rank coal surface were significantly covered by NPEO15. Furthermore, while the content of C–C/C–H functional groups increased significantly, that of C–O functional groups decreased after absorption. These results clearly indicate that low rank coal is more hydrophobic and displays better floatability.

12

X-ray photoelectron spectroscopy (XPS) study of Heusler alloy (Co2FeAl) interfaced with semiconductor (n-Si) structure

Kumar Arvind, Srivastava P. C.

Materials Science Poland

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2019

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Vol. 37, No. 1

116--121

EN

Layered magnetic heterostructures are very promising candidates in spintronics in which the influences of interfaces, surfaces and defects play a crucial role. X-ray photoelectron spectroscopy (XPS) study has been performed for studying in detail the chemical state and electronic structure of Co2FeAl (CFA) Heusler alloy interfaced with Si substrates. XPS survey scan spectra have clearly shown the presence of Fe, Co and Al signal along with the signal due to Si. The presence of Co, Fe and Al signal confirms the formation of CFA alloy phase. Our XPS results support our previous study [1] on CFA/Si structure in determining the magnetic and transport properties across the interface.

13

The Main Features of the Natural Sulphides Surface Modification Under the Impact of High-Power Electromagnetic Pulses

Chanturiya Valentine A., Bunin Igor Zh., Ryazantseva Maria V.

Inżynieria Mineralna

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2019

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R. 21, nr 1/2

123--127

EN

Surface changes in naturally occurring metal sulphides (pyrite, arsenopyrite, sphalerite, chalcopyrite, galena and molybdenite) due to the treatments from high – power electromagnetic pulses (HPEMP) at varying times were studied using XPS. Analysis of the obtained results revealed common patterns and differences in surface transformations. The transformations were found to include two main stages. The first stage were observed at low treatment intensities (up to N ~ 103 pulses). At this stage formation and accumulation in the surface layer of the nonstoichiometric sulphide phase, oxides and hydroxides, as well as elemental (polysulfide) sulphur and / or metastable sulphur species (thiosulfate, sulphite) were observed. The second stage (N ≥ 3 · 103 pulses) is characterized by the removal of sulphur species and renewal of the mineral surface (sulfidization). The application of HPEMP treatment to improve flotation selectivity is supported by single-mineral flotation tests. Changes in floatability as a result of HPEMP treatment are principally explained by surface phase changes.

PL

Zmiany powierzchni w naturalnie występujących siarczkach metali (piryt, arsenopiryt, sfaleryt, chalkopiryt, galena i molibdenit) w wyniku obróbki impulsami elektromagnetycznymi o dużej mocy (HPEMP) w różnym czasie badano przy użyciu XPS. Analiza uzyskanych wyników ujawniła typowe wzory i różnice w transformacjach powierzchniowych. Stwierdzono, że transformacje obejmują dwa główne etapy. Pierwszy etap obserwowano przy niskiej intensywności działania impulsami (do N ~ 103 impulsów). Na tym etapie zaobserwowano tworzenie i akumulację w warstwie powierzchniowej niestechiometrycznej fazy siarczkowej, tlenków i wodorotlenków, a także siarki elementarnej (polisiarczkowej) i / lub metastabilnej (tiosiarczan, siarczyn). Drugi etap (N ≥ 3 · 103 impulsów) charakteryzuje się usuwaniem rodzajów siarki i odnawianiem powierzchni mineralnej (siarczkowanie). Zastosowanie obróbki HPEMP w celu poprawy selektywności flotacji jest poparte testami flotacji pojedynczych minerałów. Zmiany flotowalności w wyniku obróbki HPEMP są wyjaśnione zmianami fazy powierzchniowej.

14

Morphological, optical and electrochromic properties of dry-lithiated nanostructured WO3 thin films

Madhuri K. V., Babu M. B.

Materials Science Poland

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2018

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Vol. 36, No. 2

341--347

EN

Tungsten trioxide (WO3) thin films were prepared by thermal evaporation technique on thoroughly cleaned glass substrates at high pressure of 133.322 mPa in presence of argon. The substrate temperature was maintained from 6 °C to 8 °C with the help of a cold jar. The deposited films were annealed at 400 °C in air for about 2 hours. The films were characterized in terms of their composition by X-ray photoelectron spectroscopy. Subsequently, the laboratory developed dry lithiation method was used to intercalate lithium atoms into as-deposited films in various proportions. With the amount of lithium content inserted into the film, the films showed coloration in visible and near infrared regions. The morphology, coloration efficiency and optical constants of annealed and lithiated films were calculated.

15

XPS studies of alite hydration products in the presence of hexavalent chromium reducers

Golonka P., Nocuń M., Nocuń-Wczelik W.

Materiały Ceramiczne

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2017

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T. 69, nr 3

258--263

EN

The X-Ray photoelectron spectrometry was applied to elucidate an impact of iron(II), tin(II) and manganese(II) sulphates on cement hydration. Iron(II) sulphate, most commonly added as a reducer of Cr(VI) to Cr(III) on cement grinding, was taken as a reference. The tin(II) and manganese(II) sulphates could be potentially used as reducers of Cr(VI) too. However, the tin(II) sulphate has very strong retarding action on cement setting. In order to find out the relevant mechanisms, the main component of Portland cement - alite (solid solution of tricalcium silicate) was used as a model material. The hydrated alite samples were subjected to the X-ray photoelectron studies to identify the surface products responsible for retarding effects. These products appeared to be quite different in the presence of particular sulphate admixtures. The formation of a Ca-Sn containing compound has been proved directly.

PL

W pracy badano wpływ siarczanów żelaza(II), manganu i cyny stosowanych w roli reduktorów Cr(VI) na proces wiązania i twardnienia cementu. W celu wyjaśnienia obserwowanych zjawisk przeprowadzono badania z udziałem alitu traktowanego jako uproszczony model cementu. Postęp hydratacji śledzono metodą mikrokalorymetryczną i stwierdzono silnie opóźniające działanie siarczanu cyny. W celu określenia w sposób bezpośredni przyczyny zahamowania hydratacji przeprowadzono badania metodą spektroskopii fotoelektronów, która daje możliwość detekcji produktów utworzonych na powierzchni hydratyzującego materiału; produkty te są różne w przypadku poszczególnych siarczanów. W ten sposób potwierdzono bezpośrednio obecność związku cyny i wapnia w warstwie powierzchniowej, stanowiącej barierę hamującą proces hydratacji w stadium początkowym.

16

Analiza składu chemicznego i fazowego cienkich warstw metalicznych

Lukaszkowicz K., Staszuk M., Nuckowski P.

LAB Laboratoria, Aparatura, Badania

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2017

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R. 22, nr 5

24--29

17

Analiza techniczno-ekonomiczna małych płyt fundamentowych na izolacji EPS i XPS

Knyziak P., Kułakowski T.

Inżynieria i Budownictwo

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2017

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R. 73, nr 10

542--544

PL

Przedstawiono analizę możliwości wykorzystania styropianów EPS i XPS jako izolacji termicznej dla płyt fundamentowych w domach energooszczędnych wraz z oceną ekonomiczną omawianego rozwiązania. Przedstawiono parametry wytrzymałościowe styropianów, wyniki obliczeń statycznych i analizy ekonomicznej 3 modeli budynków i 3 wariantów rozwiązań izolacji.

EN

The authors have presented analysis of possibilities of using EPS/XPS Styrofoam for lost formwork for slab foundations in sustainable buildings including economic analysis of capital expenditure and operating expenses. The strength parameters of Styrofoam, the results of static calculation and economic analysis for 3 building models and 3 variants of insulation solutions were presented.

18

Surface Characterization of Low Temperature Plasma-Induced Cashmere Fibre by Air Gas

Wang Y., Yu W.

Fibres & Textiles in Eastern Europe

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2017

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Vol. 25, no. 5 (125)

37--41

EN

Low temperature plasma (LTP) processing technology was successfully applied to modify cashmere fibres and three kinds of assemblies were formed, i.e., weak-treated, optimised-treated and severe-treated ones. Treatment parameters were optimised in terms of the tensile behaviour, friction effect, wettability and touch feeling of cashmere without major modification of the properties inside the fibre. Detailed characterisation was performed to investigate the surface morphologies and chemical compositions of plasma-induced fibres. SEM demonstrates different minor etching effects of the treated cashmere fibres. XPS results indicate a significant increase in surface concentrations of O and N, and an obvious decrease in C after different LTP treatments as a whole. The C-H/C-C non-polar bonds were reduced and C-O/C-N, C = O polar groups were remarkably increased on the cashmere surface after plasma modification. In addition, a carboxyl group (O-C = O) formed. It is found that oxygen-containing bonds, namely, C-O/C-N, C = O and O-C = O, are responsible for the hydrophilic properties of cashmere.

PL

W pracy przedstawiono modyfikację włókien kaszmirowych przy zastosowaniu niskotemperaturowej plazmy (LTP). Zastosowano trzy intensywności obróbki. Parametry obróbki zostały zoptymalizowane pod kątem uzyskania odpowiednich właściwości włókien tj. wytrzymałość na rozciąganie, odporność na tarcie, zwilżalność i chwyt. Za pomocą SEM i XPS dokonano szczegółowej charakterystyki morfologii powierzchni i składu chemicznego włókien poddanych działaniu plazmy. Stwierdzono że obróbka plazmą niskotemperaturową może powodować pogorszenie chwytu wyrobu końcowego, z tego powodu produkty poddawane obróbce plazmą należy poddawać dodatkowym obróbkom przemysłowym, takim jak np. zmiękczanie.

19

Spontaneous Formation of Titanium Nitride on the Surface of a Ti Rod Induced by Electro-Discharge-Heat-Treatment in an N2 Atmosphere

Lee W. H., Yoon Y. H., Kim Y. H., Lee Y. K., Kim J. Y., Chang S. Y.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2B

1281--1285

EN

A single pulse of 2.0 to 3.5 kJ of input energy from a 450 mF capacitor was applied to a commercially pure Ti rod in a N2 atmosphere. The surface of the Ti rod transformed from TiO2 into titanium nitride in times as short as 159 msec, providing a bimodal morphology of the cross-section. A much higher value of hardness that was observed at the edge of the cross-section was attributed to nitrogen-induced solid-solution hardening that occurred during the electrical discharge process. The activation energy (Ea) for the diffusion process was estimated to be approximately 86.9 kJ/mol. Results show that the electrical discharge process is a possible potential method for the nitriding of Ti; advantages include a short processing time and control of the nitrided layer without dimensional changes.

20

Colossal dielectric constant of NaNbO3 doped BaTiO3 ceramics

Cao W. Q., Xu L. F., Ismail M. M., Huang L. L.

Materials Science Poland

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2016

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Vol. 34, No. 2

322--329

EN

BaTiO3 ceramics doped with 0.40 mol% NaNbO3 were prepared using a traditional approach by sintering at temperature of 1250 ºC to 1290 ºC. The prepared ceramics was characterized by very good dielectric properties, such as high dielectric constant (1.5 × 105), low dielectric loss (0.1), and good dielectric temperature stability in the −40 ºC to 100 ºC range for the sample sintered below 1270 ºC. The dielectric characteristics obtained with XPS confirmed that Ti4+ ions remain in the state without any change. The huge increase in dielectric constant in NaNbO3 doped BaTiO3 samples occurs when large amount of Ba2+ ions are excited to a high energy bound state of Ba2+ − e or Ba+ to create electron hopping conduction. For samples with the content of NaNbO3 higher than 0.40 mol%, or sintering temperature higher than 1280 ºC, compensation effect is dominated by cation vacancies with sharply decreasing dielectric constant and increased dielectric loss. The polaron effect is used to explain the relevant mechanism of giant dielectric constant appearing in the ferroelectric phase.