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1

Właściwości tribologiczne powłok DLC smarowanych cieczą jonową

Madej Monika, Kowalczyk Joanna, Ozimina Dariusz

Obróbka Metalu

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2020

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nr 4

40--46

PL

W artykule przedstawiono wybrane właściwości powłoki TiN osadzonej na stali 100Cr6 techniką fizycznego osadzania z fazy gazowej (PVD). Określono parametry tribologiczne, a mianowicie współczynnik tarcia i zużycie liniowe na testerze TRB3 pracującym w skojarzeniu trącym kula-tarcza w ruchu ślizgowym. Tarcza wykonana była ze stali 100Cr6 z powłoką a-C:H, a kula ze stali 100Cr6. Badania wykonano w warunkach tarcia technicznie suchego i ze smarowaniem cieczą jonową bis(trifluorometylosulfonylo) amidem triheksylotetradecylofosfoniowym. Obserwacje struktury powłoki zrealizowano przy użyciu mikroskopu skaningowego, a analizę struktury geometrycznej powierzchni próbek przed i po testach tribologicznych wykonano profilometrem optycznym. Wyniki badań wskazały, że mniejszą wartość współczynnika tarcia, lecz większe zużycie tarczy uzyskano w warunkach smarowania cieczą jonową.

EN

The paper presents selected properties of a-C:H coating deposited on 100Cr6 steel deposited by physical vapour deposition PVD. Tribological parameters were determined on the TRB3 tester operating in a ball-disc friction combination in sliding motion. The disc was made of 100Cr6 steel with a-C:H coating, and the ball was made of 100Cr6 steel. The tests were conducted under dry friction conditions and with trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)amide ionic liquid lubrication. The coating structure was observed using a scanning electron microscope. The surface texture of the samples was performed with an optical profilometer. The test results showed that the smaller coefficient of friction and wear of disc was obtained after friction with lubrication ionic liquid.

2

Mineralogical, geochemical and gemological investigation of Artova Ch-chalcedonies, Tokat – Turkey

Başıbüyük Zeynel, Akbudak Ilkay Kaydu, Gürbüz Meltem

Gospodarka Surowcami Mineralnymi

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2020

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T. 36, z. 1

77--92

EN

Ch-chalcedony is a green colored member of the quartz group of gem stones. The appearance of Ch-chalcedony is very similar to that of chrysoprase. Differently, Ch-chalsedonies have a chromium element instead of a nickel element as a trace element. Green quartz used in jewelery as a seal stone, in necklaces and rings and has been one of the most valuable quartz varieties throughout history, with its beautiful green color, more rare than other quartz varieties. The Ch-chalcedonies in the North Anatolian region is yellowish-white, brownish gray, light green to dark green in color ranging from several centimeters to one meter thick in veins and lenses in the Lower-Middle Eocene dolomitic limestones. Ch-chalcedonies are composed of fine-grained and occasionally fibrous needle-like quartz; in some examples, quartz is present together with cristobalite, tridimite and cuspidine minerals. According to geochemical investigations in Ch-chalcedonies, the main oxides that were determined are as follows: SiO2 was observed in the range of 95.86–97.81%, Fe2O3 was observed in the range of 0.61–0.91% and Cr2O3 was observed in the range of 0.125–0.168%. A trace element analysis of Ch-chalcedonies, shows their significant enrichments in: Ni, Mo, Cu, Mn, V, Cr and W, especially in the Cr (up to 705 ppm). The green color of the studied Cr-chalcedonies originates from the element chromium. Taking the possible reserves into account, the hardness, color, massive structures, mineralogical, petrographical and gemological features of Ch-chalcedonies in the region are evaluated together. It is determined that they are suitable for the production of jewelry and ornaments.

PL

Ch-chalcedon jest składnikiem kwarcowej grupy kamieni szlachetnych w kolorze zielonym. Wygląd Ch-chalcedonu jest bardzo podobny do chryzoprazu. W szczególności Ch-chalcedony zawierają pierwiastek chromu zamiast pierwiastka niklu jako pierwiastka śladowego. Zielony kwarc stosowany w biżuterii jako kamień do: pieczętowania, naszyjników i pierścionków był jedną z najcenniejszych odmian kwarcu w historii dziejów. Ch-chalcedony w regionie północnoatlantyckim mają żółtawo-biały, brązowo-szary kolor od jasnozielonego do ciemnozielonego o grubości od kilku centymetrów do jednego metra, występują w żyłach i soczewkach wapieni dolomitycznych dolno-środkowego eocenu. Ch-chalcedony składają się z drobnoziarnistego i czasami włóknistego igłopodobnego kwarcu; w niektórych próbkach kwarc występuje razem z minerałami krystobalitu, tridymitu i kuspidyny. Według badań geochemicznych w Ch-chalcedonach zawartość głównych tlenków kształtowała się następująco: SiO2 zaobserwowano w zakresie 95,86–97,81%, Fe2O3 zaobserwowano w zakresie 0,61–0,91%, a Cr2O3 zaobserwowano w zakresie 0,125–0,168%. Analiza pierwiastków śladowych Ch-chalcedonów pokazuje ich znaczące wzbogacenie w: Ni, Mo, Cu, Mn, V, Cr i W, szczególnie w Cr (do 705 ppm). Zielony kolor badanych Ch-chalcedonów pochodzi od pierwiastka chromu. Obecnie oceniane są: możliwe zasoby, twardość, kolor, struktury, cechy mineralogiczne, petrograficzne i gemologiczne chalcedonów w analizowanym regionie. Ustalono, że te Ch-chalcedony nadają się do produkcji biżuterii i ozdób.

3

Analysis of data aggregation methods and related issues in Wireless Sensor Networks

Nels S. Ninisha, Singh J. Amar Pratap

Control and Cybernetics

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2020

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Vol. 49, No. 4

419--446

EN

Data aggregation is the process aimed at reducing the transmission count of packets being transmitted in the framework of in-network data processing. It is the data transmission model that takes the information transmitted from different nodes and generates a single data packet after finding and eliminating the redundant packets. Accordingly, this process decreases the transmission count and makes it possible to consume less energy. The major issues in data aggregation mechanism are related to reduction of latency and to energy balancing. Moreover, it is very complex to resolve the issue of packet loss, which is the failure of one or more transmitted packets to arrive at their destination due to the bad and/or congested channel conditions. The present survey involves a collection of 50 research papers dealing with the data aggregation models in wireless sensor networks (WSN). Various data aggregation methods, like the cluster-based approach, structure-free method, tree-based approach, in-network methods, and energy based aggregation model are considered in this survey, regarding the application and the energy usage involved. On the basis of the survey, the issues and drawbacks faced by the respective methodologies are highlighted. In addition, the paper presents simple statistics of the studies considered with respect to the performance measures, simulation tools, publication year, and classification of methods. The future dimensions of the respective research are supposed to be based on the challenges identified in this survey.

4

Halogenated organic compounds in water and in wastewater

Włodarczyk-Makuła Maria, Wiśniowska Ewa

Civil and Environmental Engineering Reports

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2019

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Vol. 29, no. 4

236--247

EN

Currently, organic halogen compounds (halogen derivatives) are often identified in water. The paper presents the problem of the presence of these newly formed compounds during water treatment processes and their occurrence in sewage. The general indicator determining the content of these compounds in aqueous solutions is the concentration of halogen derivatives of organic compounds adsorbed on activated carbon AOX, which is converted to the concentration of chlorides. The groups of derivatives of halogenated organic compounds containing chlorine and/or bromine in a molecule were characterized, and the precursors and potential for the formation of these compounds in water were described. Moreover, technological methods to prevent and remove them were described.

5

Curing Properties of Furotec 132 Resin- Bonded Foundry Sand

Mashingaidze M. M.

Archives of Foundry Engineering

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2019

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iss. 4

117--123

EN

The study evaluated the curing properties of natural silica sand moulded with 1% by weight Furotec 132 resin binder catalysed by Furocure CH Fast acid and Furocure CH Slow acid. Physical properties of this sand included an AFS number of 47.35, 4.40 % clay, 0 % magnetic components, 0.13 % moisture, and 64.5 % of the size distribution spread over three consecutive sieves (150 – 600 μm). The sand was washed repeatedly to remove all the clay and oven dried. 2 kg washed sand samples were mulled with pre-determined weights of either catalyst to give 30 %, 50 % and 70 % by weight of 20 g Furotec 132 resin which was added last. Furotec 132 resin + Furocure CH Slow acid catalyst system gives longer bench lives and strip times but the maximum compressive strength in excess of 5000 N/cm2 is attained after more than 8.5 hours curing time irrespective of the weight % of catalyst added relative to the resin. On that basis, exceeding 30 weight % Furocure CH Slow acid catalyst when sand moulding with Furotec 132 resin has neither technical nor economic justification. In comparison, the Furotec 132 resin + Furocure CH Fast acid catalyst system was only capable of producing mould specimens with maximum compressive strength above 5000 N/cm2 at 30 weight % catalyst addition rate. At 50 and 70 weight % catalyst addition rates, the mulled sand rapidly turned dark green then bluish with a significant spike in temperature to about 40 oC, far exceeding the optimum curing temperature of Furotec 132. This high temperature accelerates the curing rate but with a very low degree of resin curing which explains the low compressive strength. In fact the sand grains fail to bond and have a dry, crumbly texture implying dehydration. Thus, not more than 30 weight % Furocure CH Fast acid catalyst should be used in sand moulding.

6

An AI Approach to Locate Cluster Centre in Wireless Sensor Networks

Sandhya R., Sengottaiyan Nallasamy

Annals of Computer Science and Information Systems

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2017

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Vol. 10

289--292

EN

Wireless sensor networks, which consist of a immense number of sensor nodes have emerged as an inevitable, effective and important technology in tele-communication field. Sensor nodes can be deployed in any harsh environment for health monitoring, industrial monitoring, structural analysis, detecting intruders etc. Since it works in battery, the major challenge is to improve the lifetime of sensor node by effectively reducing energy consumption. Otherwise, it is very difficult to frequently replace the sensor nodes. For this, many routing protocols have been proposed in which cluster based routing protocol plays a vital role. In cluster based routing protocol, entire WSN network is divided into several groups or clusters. Then for each cluster a cluster head (CH) is selected. Sensors sense the data and forward it to their corresponding CH where the entire data of that cluster get aggregated and transmitted to base station (BS). The clustering technique offers more benefit than existing flat based routing protocols since the data is transmitted via CH rather than directly by each sensor nodes. Thus the selection of CH is very important. Here we proposed a method named firefly based nearest neighbor chain algorithm to select the centre of cluster based on which CH selection can be done.

7

Jakość i efektywność szkoleń BHP – ewaluacja procesu nauczania

Oleksy J.

Promotor BHP

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2016

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nr 1-2

23--26

PL

Profesjonalne szkolenie BHP polega na tym, aby uczestnik kursu przyswoił sobie jak najwięcej wiedzy w zakresie bezpieczeństwa pracy, w jak najkrótszym czasie. Miejsce szkolenia, odpowiednie warunki sal szkoleniowych, odpowiednie pomoce dydaktyczne oraz wykwalifikowana kadra szkoleniowców to elementy, które znacząco przekładają się na efektywne i dobre szkolenie.

8

Zielony dach Magnolia Park we Wrocławiu

Muszyński P., Pączkowski A.

Nowoczesne Hale

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2014

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Nr 4

48--50

PL

Pod koniec 2013 roku ruszyła rozbudowa CH Magnolia Park we Wrocławiu. Podjęto decyzję o zastosowaniu systemu dachu zielonego, aby uwzględnić powierzchnię biologicznie czynną bez utraty powierzchni działki.

9

Badanie struktury i dynamiki N-terminalnych sekwencji dermorfiny i ich analogów z wykorzystaniem spektroskopii NMR w ciele stałym i rentgenografii

Trzeciak-Karlikowska K.

Wiadomości Chemiczne

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2012

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[Z] 66, 9-10

867-891

EN

Deltorphin I (Tyr-d-Ala-Phe-Asp-Val-Val-Gly-NH_2) and dermorphin (Tyr-d-Ala-Phe- -Gly-Tyr-Pro-Ser-NH_2) are natural opioid peptides that have been isolated from the skin of South American frogs [1]. The presence of d-amino acid is crucial for their biological activity. The synthetic analogs of given heptapeptides containing l-alanine are not analgesics [2]. Analysis of the influence of stereochemistry on molecular packing, dynamics and biological functions of neuropeptides is still important for receptor studies and practical applications (e.g. design of new selective pain killers). Presented research is focused on the structure and dynamics of two N-terminal sequences of dermorphin: tripeptide Tyr-d-Ala-Phe 1, tetrapeptide Tyr-D-Ala-Phe-Gly 2, and their analogs with l-alanine: Tyr-Ala-Phe 3 and Tyr-Ala-Phe-Gly 4, using solid state NMR and X-ray diffraction. This study clearly demonstrates that 1 and 2 crystallized under different conditions to form exclusively one structure [3, 4]. In contrast, tripeptide and tetrapeptide with l-Ala in the sequence very easily form different crystal modifications. Tyr-Ala-Phe 3 crystallizes into two forms: 3a and 3b [5], while Tyr-Ala-Phe-Gly 4 gives three modifications: 4a, 4b and 4c [4]. It seems that one of the factors, which can be important in the preorganization mechanism anticipating the formation of crystals, is the intramolecular CH-đ interaction between aromatic rings of tyrosine and/or phenylalanine and the methyl group of alanine. Such interaction is possible only for d-Ala residue. For l-Ala in the peptide sequence, the methyl group is aligned on the opposite side with respect at least to one of the aromatic groups. It can be further speculated that such internal CH-π contacts can also occur during the interaction of ligand–receptor, making the message sequence of opioid peptides more rigid and finally selective. By employing different NMR experiments (e.g. PISEMA MAS and PILGRIM) it was proven that the main skeleton of analyzed peptides is rigid, whereas significant differences in the molecular motion of the aromatic residues were observed [4, 6]. Solid state 2H NMR spectroscopy of samples with deuterium labeled aromatic rings: Tyrd4-d-Ala-Phe 5, Tyr-d-Ala-Phed5 6, Tyrd4-Ala-Phe 7, Tyr-Ala-Phe^d5 8 was used to analyze the geometry and time scale of the molecular motion. At ambient temperature, the tyrosine ring of sample 5 is rigid and in the sample 6 the phenylalanine ring undergoes a "π -flip". The tyrosine rings of form I of 7 and 8 are static, while the phenylalanine rings of form II of 7 and 8 undergo a fast regime exchange [6]. Variable temperature 2H measurements proved that the tyrosine and phenylalanine rings of two forms of compounds 7 and 8 became more mobile with increasing temperature. In contrast, the aromatic rings of samples 5 and 6 preserve their dynamics regime (static tyrosine and "π -flip" phenylalanine) in a large range of temperatures [6]. The analysis of 13C, 15N labeled tetrapeptide Tyr-D-Ala-Phe-Gly 2’-phospholipid membrane interactions suggests that peptide 2’ is aligned on the surface of the membrane (RFDR MAS) and the sandwich-like π -CH_3-π arrangement of the pharmacophore is preserved (DARR) [7].

10

Kogeneracja - dobór układów chp

Rozmarynowski A., Wojciechowski J.

Logistyka

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2011

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nr 6

PL

Artykuł dotyczy problematyki kogeneracji, tj. skojarzonego wytwarzania energii cieplnej i elektrycznej. Podano podstawy doboru układów CHP oraz na praktycznym przykładzie pokazano sposób doboru urządzenia.

EN

The paper presents cogeneration issue - concurrent generation of electric and heat energy. The overall concept of the choice of CHP circuits as wells as practical example of such choice have been presented.

11

Miejskie połączenia z krajobrazem otwartym Poznania, Krakowa i Warszawy w XIX i XX w.

Nadolny A.

Zeszyty Naukowe Politechniki Poznańskiej. Architektura i Urbanistyka

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2007

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Z. 9

43-57

PL

W artykule omówiono zjawisko miejskich połączeń z krajobrazem otwartym (ang. City country fingers) przedstawionych przez Ch. Alexandra w pracy A pattern language. Kształtowanie się tych połączeń w XIX i XX w. ukazano na przykładzie trzech miast: Poznania, Krakowa i Warszawy. Prezentowany artykuł jest częścią badań prowadzonych przez autora na Wydziale Architektury Politechniki Poznańskiej.

EN

The main subject of the article is the analysis of urban structures of Poznań, Cracow and Warsaw in comparison to City County finger pattern, included in the book written by Christopher Alexander "A Pattern Language". Moreover shows the result of the researches, in reference to Polish cities such as Cracow, Poznań and Warsaw in XIX and XX century. The three chosen cities Poznań, Cracow and Warsaw were researched within the space 19th and 20th century, when the cities played a role in the urban development in Poland. To sum up the researches have to answer the question which part of pattern, created by Christopher Alexander, we can find in Poznań, Cracow and Warsaw.

12

FT-IR Studies of CH...B Interactions in Fluoroform Containing Cryosolutions

Melikova S., Rutkowski K. S., Rodziewicz P., Koll A.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 9

1271-1285

EN

A transition from a blue shifted frequency of the _(CH) vibrations of CF3H to a conventional red frequency shift, accompanied by unusually varying integrated intensity of the corresponding _1 band, have been studied in CF3H/B systems, where B = Ar, N2, CO, CO2, O(CD3)2, NH3, and N(CD3)3. DFT/B3LYP and ab initio MP2 calculations, utilizing the 6-311++G(3df,3pd) basis set, predict a weakly H-bond-like linear F3CH…B complex formation in the series studied and reproduce experimentally observed variations of spectroscopic parameters. The results obtained are treated in the framework of induced dipole moment, taking into account opposite directions of the CH bond dipole moment and the dipole moment of the whole molecule. In the range of overtone and combination bands of fluoroform, new weak bands have been detected. They were attributed to simultaneous excitations of vibrations of interacting CF3HandB(=CO,CO2) molecular pairs.

13

Quantum chemical description of catalytic activation of the C-H bond

Bracławik E.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 7S

1551-1564

EN

Density functional theory is presented from the point of view of its applicability in modelling catalytic reaction. Reaction path for C-H bond scission in methane interacting with metal oxide/transiton metal catalytic sites for gallium oxide in zeolitic lattice and palladium or rhodium based supported catalysts are analysed. On the basis of interdependence between the elektronic structure and activity of the bond two mechanisms for activation of the C-H bond are described: via electrons withdrawal from bonding states (on oxide catalysts) and via electron insertion to antibonding orbitals (on metals).