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1

Electron work functions of (h k l)-surfaces of W, Re, and Cu crystals

Surma S. A., Brona J., Ciszewski A.

Materials Science Poland

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2018

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Vol. 36, No. 2

225--234

EN

Work function (WF) and some physicochemical data for several most prominent crystal planes of three metals of typical structures are calculated within the linear approximation employing the surface dipole and 2D gas models. “Composite” crystal of a homogeneous bulk phase and a thick surface composed of eight (h k l)-oriented facets with different unsaturated bonds is treated as a nine-phase nine-component system with two degrees of freedom. It contains the two-dimensional metal-lattice plasma of free electrons and the immobile atom-core network. For twenty four (h k l) surfaces, the WF and dipole barrier term, chemical and electrostatic potential levels, electron charge densities, surface dipole fields, and other parameters are calculated and tabularized. WF values obtained from the thermodynamics based formula are compared to the ones obtained from the quantum mechanics based formula, which shows good agreement with experiment and also reveals a specific deviation in the case of field emission method for the most packed plane. A set of accurate face dependent data can be of interest to electronics and materials science workers.

2

AFM studies of pits formation on KBr(1 0 0) during its dissolution by water

Pers J., Barwiński B., Grodzicki M., Ciszewski A.

Materials Science Poland

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2016

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Vol. 34, No. 4

863--867

EN

The formation of etch pits along screw dislocations on KBr(1 0 0) surface during its dissolution by water is investigated by means of atomic force microscopy (AFM). Clean KBr(1 0 0) is obtained by cleavage. A weak solution of water in isopropyl alcohol is used to investigate the etching in real time. Observations of the etch pit evolution with etching time show that concentration of atomic steps on the pit walls and dissolution rate of the walls vary up to complete dissolution of the screw dislocation. The screw dislocation removal stabilizes the dissolution, resulting in constant values of atomic steps concentration on the pit walls and their dissolution rate during further etching, which continues according to the crystal dissolution stepwave model. It was found that the movement of AFM scanning tip essentially affected the etching process.

3

Two-extremum electrostatic potential of metal-lattice plasma and the work function of an electron

Surma S. A., Brona J., Ciszewski A.

Materials Science Poland

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2015

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Vol. 33, No. 2

430--444

EN

Metal-lattice plasma is treated as a neutral two-component two-phase system of 2D surface and 3D bulk. Free electron density and bulk chemical potential are used as intensive parameters of the system with the phase boundary position determined in the crystalline lattice. A semiempirical expression for the electron screened electrostatic potential is constructed using the lattice-plasma polarization concept. It comprises an image term and three repulsion/attraction terms of second and fourth orders. The novel curve has two extremes and agrees with certain theoretical forms of potential. A practical formula for the electron work function of metals and a simplified schema of electronic structure at the metal/vacuum interface are proposed. This yields 10.44 eV for the Fermi energy of free electron gas; ~5.817 eV for the Fermi energy level; 4.509 eV for the average work function of bcc tungsten. Selected data are also given for fcc Cu and hcp Re. For harmonic frequencies 10E16 per s of the self-excited metal-lattice plasma, energy gaps of 14.54 and 8.02 eV are found, which correspond to the bulk and surface plasmons, respectively. Further extension of this thermodynamics and metal-lattice theory based approach may contribute to a better understanding of theoretical models which are employed in chemical physics, catalysis and materials science of nanostructures.

4

Jan Czochralski działacz Stowarzyszenia inżynierów Mechaników Polskich w latach 1929-1939

Ciszewski A.

Zeszyty Historyczne Politechniki Warszawskiej

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2014

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z. 15

37--47

5

Pd/GaN(0001) interface properties

Grodzicki M., Mazur P, Zuber S., Pers J, Ciszewski A.

Materials Science Poland

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2014

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Vol. 32, No. 2

252--256

EN

Institute of Experimental Physics, University of Wroclaw, pl. Maxa Borna 9, 50-204 Wrocław, Poland This report concerns the properties of an interface formed between Pd films deposited onto the surface of (0001)-oriented n-type GaN at room temperature (RT) under ultrahigh vacuum. The surface of clean substrate and the stages of Pd-film growth were characterized in situ by X-ray photoelectron spectroscopy (XPS), scanning tunneling microscopy (STM), ultraviolet photoelectron spectroscopy (UPS), and low energy electron diffraction (LEED). As-deposited Pd films are grainy, cover the substrate surface uniformly and reproduce its topography. Electron affinity of the clean n-GaN surface amounts to 3.1 eV. The work function of the Pd-film is equal to 5.3 eV. No chemical interaction has been found at the Pd/GaN interface formed at RT. The Schottky barrier height of the Pd/GaN contact is equal to 1.60 eV.

6

TiO2 thin films grown on SiO2–Si(111) by the reactive evaporation method

Grodzicki M, Wasielewski R, Mazur P, Zuber S, Ciszewski A

Optica Applicata

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2013

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Vol. 43, nr 1

99--107

EN

TiO2 thin films were grown on silicon substrates using an electron-beam evaporator. Grainy TiO was used as the evaporation material. Temperature substrate during TiO2 growth was relatively low (about 150 °C), what is important for many optoelectronic devices and multilayers mirrors. High vacuum condition allows to maintain clean surfaces substrates before and during oxide growth. The morphology of titanium oxide thin films was ex situ investigated using atomic force microscopy operating in contact mode, X-ray photoelectron spectroscopy, X-ray powder diffractometry, and by means of a contact angle analyzer. The influence of annealing treatment and exposure to UV–VIS radiation on the morphology has been also discussed.

7

Formation of Cr ohmic contact on graphitized 6H-SiC(0001) surface

Grodzicki M, Mazur P, Wasielewski R, Ciszewski A

Optica Applicata

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2013

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Vol. 43, nr 1

91--98

EN

Ohmic electrical contacts were formed at room temperature on n-type, Si-oriented 6H-SiC substrates, with Cr layers vapor-deposited under ultra-high vacuum conditions on the samples being graphitized prior to the deposition. The contacts reveal a very good linearity of the local I–V characteristics. This method of ohmic contact formation does not require the use of samples with high doping concentration and the application of high-temperature annealing during the processing of contacts. Results of characterization of the contacts and of the in situ graphitization process of the SiC substrates, obtained by X-ray photoelectron spectroscopy (XPS), low energy electron diffraction (LEED) and atomic force microscopy (AFM) with conducting tip, are given in this paper.

8

Renowacja krzyża na Giewoncie

Mikoś T., Ciszewski A.

Nowoczesne Budownictwo Inżynieryjne

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2011

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Nr 1

71-73

PL

Metalowy krzyż na Giewoncie od przeszło stu lat należy do najbardziej znanych i rozpoznawalnych symboli polskich Tatr, Podhala i samego Zakopanego. Stanowi wyrazisty symbol uczuć religijnych i patriotycznych Polaków. Jest też czytelnym punktem orientacyjnym w górach i celem wędrówek tysięcy turystów. Z tego względu informacje o pogarszającym się stanie technicznym konstrukcji zabytkowego krzyża oraz podłoża, na którym go posadowiono, budzą od lat wielkie emocje i niebywałe zaciekawienie.

9

Cr ohmic contact on an Ar+ ion modified 6H-SiC(0001) surface

Grodzicki M., Chrzanowski J., Mazur P., Zuber S., Ciszewski A.

Optica Applicata

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2009

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Vol. 39, nr 4

765-772

EN

Chromium layers were vapor deposited under ultrahigh vacuum onto samples cut out of a single crystal of 6H-SiC(0001) that were Ar+ bombardment modified. The substrates and electrical contacts formed by the Cr adlayer were characterized in situ by current-sensing atomic force microscopy (CS-AFM) and X-ray photoelectron spectroscopy (XPS). Cr/SiC contacts reveal a good I-V characteristic linearity without the use of heavy impurity doping and high-temperature annealing.

10

Effects of Ar+ ion sputtering on morphology and electric conductance of 6H-SiC (0001) surface

Mazur P., Zuber S., Grodzicki M., Ciszewski A.

Materials Science Poland

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2008

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Vol. 26, No. 2

265--269

EN

The paper reports surface modification of SiC by Ar+ ion sputtering. Observations were performed with an ultra high vacuum atomic force microscope operating in the contact mode. The surface morphology and topography were investigated with simultaneous measurement of local changes in electric conductance. We show that the Ar+ ion bombardment of the 6H-SiC wafer surface affects the surface stoichiometry, changing the character of a metal/SiC contact from the Schottky barrier diode type into an ohmic contact type.

11

Wpływ temperatury oraz zawartości grafitu i tlenku magnezu w masie katodowej na osiągi ogniw termicznych o układzie elektrochemicznym Li|LiCl-KCl-RbCl-LiF|FeS2

Styczyński S., Ciszewski A., Sołopa W.

Przemysł Chemiczny

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2006

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T. 85, nr 8-9

1234-1236

PL

Przeprowadzono pomiary dla modelowych ogniw termicznych o układzie elektrochemicznym Li(Fe)-FeS2 i konstrukcji zamkniętej, w których zastosowano elektrolit LiCl-KCl-RbCl-LiF oraz trzy rodzaje mas katodowych, różniących się zawartością grafitu i tlenku magnezu. Pomiary polegały na wyładowaniu ogniw przez stały opór i przeprowadzone zostały w zakresie temp. 655-905 K. Wyznaczono zależności napięcia od oddanej pojemności elektrycznej, średniego napięcia pracy od temperatury operacyjnej i uzyskanej pojemności elektrycznej od temperatury operacyjnej.

EN

Elec. properties of sealed-model thermal cells in the Li(Fe)-FeS2 system with 78.4% (LiCl-KCl-RbCl)(eutectic)1.6%LiF as electrolyte were examd. in relation to graphite (4.5 or 9%) and MgO (4.5 or 9%) content in the cathode material. The cells were discharged over 655-905 K; working voltage rose as temp. was raised. At higher C, the av. work voltage was higher; at 9%C, 1.4 V was achieved at 655 K (vs. the 680 K at 0%C). At 755-805 K, the elec. capacity was max. With C alone (no MgO) as additive, the voltage characteristics was most stable.

12

Porównanie właściwości fizykochemicznych wybranych separatorów stosowanych w akumulatorach zasadowych

Rydzyńska B., Ciszewski A.

Przemysł Chemiczny

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2006

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T. 85, nr 8-9

1212-1215

PL

Scharakteryzowano trzy dostępne na rynku separatory do ogniw z elektrolitem zasadowym, które badane były w akumulatorach niklowo–kadmowych (0,36 Ah) prądami rozruchowymi (8 C) przez 200 cykli. Wyznaczano pojemność ogniw, oporność wewnętrzną, a także pojemność rozruchową. Wykonano badania właściwości fizykochemicznych w celu określenia zmian degradacyjnych separatorów, zachodzących podczas pracy cyklicznej akumulatorów. Przeprowadzono m.in. badania oporności elektrolitycznej, które wykazały wzrost oporności w przypadku separatora „warstwowego”, analizę rentgenostrukturalną, ukazującą degradację separatora celulozowego, a także pomiary powierzchni właściwej metodą BET.

EN

Internal resistance, BET surface, deg. of crystallinity, crystallite size, and starting capacity were examd. in 3 com. separators, (I) standard cellulose type (Celofan 350POO), (II) knitted fabric-laminated isotactic PP (Celgard 3501), and (III) hydrophilic PP (Celgard 5550), used for 0.36-A·hr. Ni–Cd cells (1.28 g/ml KOH), operated for 40–200 charging (0.2 C)–discharging (8 C) cycles. In 200 cycles, crystallinity fell from (I) 34.8 to 5.2, (II) 63 to 30.2, and (III) 75.6 to 69.4%; BET was (I) nearly same, 6.6–7.6, and rose from (II) 26.6 to 65.1, and (III) 15 to 33.8 m2/g; At c.d. 2 mA/cm2, the electroelectro lytic resistance of each separator was hardly affected, 5–10 mohm·cm2; at 80 mA/cm2, it rose only in III.

13

Model rezerwowej baterii aktywowanej termicznie na bazie układu Li/KCI-LiCI-RbCI-LiF/FeS2

Styczyński S., Czajka B., Tabat S., Szcześniak B., Ciszewski A., Wachowski L., Sołopa W., Rydzyńska B.

Problemy Techniki Uzbrojenia

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2006

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R. 35, z. 97

233--240

PL

Opracowano model nowej baterii rezerwowej aktywowanej termicznie opartej na układzie elektrochemicznym Li|KCl-LiCl-RbCl-LiF|FeS2 oraz mieszanine grzewczej Fe-KClO4. W badaniach stosowano dwuogniwową baterią termiczną, dla której wyznaczono wartość jej pojemności cieplnej oraz określono optymalną masę tabletki mieszaniny grzewczej. Ponadto określono wpływ niedogrzania lub przegrzania baterii na podstawowe parametry elektryczne oraz wyznaczono wartości temperatury poszczególnych jej elementów.

EN

The model of a new thermally activated stand-by battery based on the electrochemical chain Li/KCl-LiCl-RbCl-LiF/FeS2 and heating composition of Fe-KClO4 was developed. A thermal two-cell battery was used for tests and its thermal capacity and the optimal mass of the heating tablet was determined. Moreover the dependence of battery electric performance on overheating and not sufficient heating was presented in the paper. There are also included temperatures of battery’s particular components.

14

The effect of the heating medium on the electric parameters of a thermal battery with the electrochemical system Li | LiCl-KCl-RbCl-LiF | FeS2

Styczyński S., Czajka B., Sołopa W., Rydzyńska B., Ciszewski A.

Polish Journal of Chemical Technology

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2006

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Vol. 8, nr 4

80-82

EN

Model thermal batteries with the electrochemical system Li | LiCl-KCl-RbCl-LiF [ FeS2, activated by a heating mixture made of powders of potassium chlorate(VII) and iron, have been characterised. The measurements of voltage and current intensity have been made on discharging the batteries over a constant resistance. The batteries performance has been tested depending on the amount and placement of the heating mixture inside the cell. The optimum electric performance of the battery has been achieved for the heating mixture in the amount close to the value, theoretically predicted on the basis of the calculated thermal balance. On insufficient heat lower voltage and shorter working time of the batteries have been established, while on too much heat the batteries have been overheated which led to frequent short-circuiting and shorter working time.

15

Wpływ rodzaju separatora na pracę cykliczną akumulatorów niklowo-wodorkowych

Rydzyńska B., Jankowska E., Ciszewski A.

Przegląd Elektrotechniczny

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2005

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R. 81, nr 1

91-94

PL

W artykule przedstawiono wyniki badań różnych typów separatorów dostępnych na rynku. Separatory te zastosowano w akumulatorach niklowo-wodorkowych (Ni/MH). Z przeprowadzonych badań wynika, że wzrost oporności elektrolitycznej separatorów polipropylenowych jest wynikiem wymywania się środka powierzchniowo - czynnego z powierzchni membrany.

EN

The paper presents the results of the testing various types of separators accessible on the market. The separators were applied in nickel-hydride batteries. The results show that the increase in the electrolytic resistance of polypropylene separators is caused by washing out the surface active agent from the membrane.

16

Pompujące własności powierzchni - pompy geterowe

Markowski L., Ciszewski A.

Prace Naukowe Politechniki Warszawskiej. Elektronika

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2005

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z. 153

33-40

EN

Most of production processes for articles of the so-called hi-tech class need employing ultrahigh vacuum. At present the degree of miniaturization of electronic circuits reaches such a level that single transistors should be treated in size as nanoscale devices. Accordingly quite esential is to ensure thedeterminate cleannes of vacuum condotions in the course of the production process since even a small admixture originating from residual gases can introduce fault of the obtained device. Apart from the conventional techniques of ultrahigh vacuum generation (turbomolecular pumps, cryotechnique), helpful in this field are becoming the pumps with the active pumping surface, or familiar getters. Action of this pumps consists in adsorption of particles of active gases and consequently, formation of stable compounds on their surfaces as a result of chemical reactions.We can distinguish here evaporable getters with the developed surface obtained by evaporation of a proper material (barium and titanium most of all) as well as the so-called non-evaporable getters (NEG) which are fabricated by fixing a powder of the getter material (usually compounds based on zirconium or titanium as well as other IVB elements of the periodic system) to an adequate substrate by sintering, pressing or cathaphoresis. Getters of this sort usually are activated by heating them to a sufficiently high temperature. In this paper discussed are the pumping mechanism and primary properties of getters that determine their pumping power for selected gases (i.e. the pumping rate, the pump capacity and their regeneration ability). Presented are als some of the wide applications of getters in industry (tubes, displays, monitors of different types, thermal insulations and screens, infrared detectors, photomultipliers etc.) in electronics (fabrication of thin layer systems, optoelectronics) as well as in research work (elementary particle accelerators and laboratory ultrahigh vacuum systems).

17

On the microstructure of TiHfOx thin films

Domaradzki J., Borkowska A., Kaczmarek D., Prociów L., Wasielewski R., Ciszewski A.

Optica Applicata

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2005

|

Vol. 35, nr 3

431-435

EN

Transition metal oxides, whose optical band gap might be modified by doping or manufacturing using two (or more) oxides with different band gaps, are good candidates for host matrices in luminescent devices. This paper presents structural properties of TiHfOx thin films and analysis of dependence of their optical properties on thin film structure. In order to examine the microstructure of manufactured thin films the X-ray diffraction (XRD) and atomic force microscopy (AFM) were applied. The optical properties of manufactured thin films were investigated by optical transmission method in the spectral range from 200 to 1400 nm.

18

Badania ludzkich kamieni żółciowych przy użyciu mikroskopu sił atomowych - osiągnięcia i trudności

Mróz I., Barwiński B., Matyka K., Ciszewski A.

Inżynieria Biomateriałów

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2005

|

R. 8, nr 47-53

116--117

19

Determination of Arsenic in Human Hair Samples of Persons in Permanent Contact with a Polluted Environment

Wasiak W., Ciszewski A., Dzioba M.

Chemia i Inżynieria Ekologiczna

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2003

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Vol. 10, nr 11

1215-1223

EN

An adsorptive cathodic determination of total arsenic in human hair samples of persons involved in the copper ore mine and copper ore smelter plant is described. The presented procedure has been optimized and can be useful for all kinds of biological samples required initial digestion before arsenic determination.

PL

Przedstawiono woltamperometryczną metodę oznaczania arsenu we włosach ludzi pracujących w kopalniach miedzi oraz zakładach hutniczych rud miedzi. Procedura analityczna została zoptymalizowana i może być stosowana do wszelkich próbek biologicznych wymagających wstępnego mineralizowania.

20

Włóknina węglowa jako materiał konstrukcyjny czujnika potencjometrycznego w pomiarach elektrokardiograficznych.

Ciszewski A., Leczykiewicz T., Posłuszny Sz., Mielczarek G.

Inżynieria Materiałowa

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2001

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R. XXII, nr 3

141-144

PL

W pracy przedstawiono badania nad wykorzystaniem włókniny węglowej jako nośnika dla układu Ag/AgCl/KCl, będącego potencjometrycznym sensorem w pomiarach elektrokardiograficznych. Proces metalizacji włókniny węglowej srebrem przeprowadzono metodą chemiczną, a wytworzenie warstewki AgCl na posrebrzanej włókninie metodą elektrochemiczną. Wytworzone czujniki charakteryzują się niskim kosztem produkcji, dobrą aktywnością i zgodnością parametrów pracy z wymogami norm. Przedstawiono wyniki charakterystyki elektrycznej sensorów, a także pokazano surową włókninę węglową oraz włókninę posrebrzoną.

EN

This study presents research on the use of carbon fabric as a carrier of the active system, Ag/AgCl/KCl, of the potentiometric sensor for the electrocardiogram measurements. The metallization process of carbon fabric has been performed chemically and generation of AgCl layer electrochemically. Application of this carrier allows the manufacturing of a low-cost and active sensor with good parameters. Electrical parameters of these sensors are presented. The surface and cross-section of naked and metallized carbon fabric are shown.