Search results

Filters

  • Journals
  • Authors
  • Keywords
  • Date
  • Type

Search results

Number of results: 14
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

Falling film, shell-tube type evaporators are commonly used heat exchangers for the production of fruit juice concentrate. The main problem in the design of the exchanger is a reliable estimation of wall heat transfer coefficients for all effects in real operating conditions. Most literature sources for the overall heat transfer coefficients are based on laboratory measurements, where the tubes are usually short, no fouling exists and the flow rate is carefully adjusted. This paper shows the heat transfer estimated in real industrial operating conditions, compared to literature sources. Paper is based on the author’s own experience in designing and launching several evaporators for juice concentrate production into operation. As a summary, the design heat transfer coefficients are provided with relation to sugar content in juice concentrate.

Go to article

Authors and Affiliations

Piotr Cyklis
Download PDF Download RIS Download Bibtex

Abstract

In the paper presented are experiences from operation of three different expansion devices for possible implementation in the domestic micro CHP. These were the modified scroll expander and two designs based on the variable working chamber volume pneumatic devices. Experiments showed the superiority of both "pneumatic devices" over the scroll expander, indicating the possible internal efficiencies in the range of 61 82Such efficiencies are very attractive, especially at the higher end of that range. The volume of these devices is much smaller than the scroll expander which makes it again more suitable for a domestic micro CHP. Small rotational velocities enable to conclude that connection to electricity grid will also be simpler in the case of "pneumatic devices". The "pneumatic devices" under scrutiny here could be an alternative to the typical vapour turbine in the ORC cycle, which is in the process of development at the IFFM.

Go to article

Authors and Affiliations

Dariusz Mikielewicz
Jarosław Mikielewicz
Jan Wajs
Download PDF Download RIS Download Bibtex

Abstract

This paper provides some information about thermoelectric technology. Some new materials with improved figures of merit are presented. These materials in Peltier modules make it possible to generate electric current thanks to a temperature difference. The paper indicates possible applications of thermoelectric modules as interesting tools for using various waste heat sources. Some zero-dimensional equations describing the conditions of electric power generation are given. Also, operating parameters of Peltier modules, such as voltage and electric current, are analyzed. The paper shows chosen characteristics of power generation parameters. Then, an experimental stand for ongoing research and experimental measurements are described. The authors consider the resistance of a receiver placed in the electric circuit with thermoelectric elements. Finally, both the analysis of experimental results and conclusions drawn from theoretical findings are presented. Voltage generation of about 1.5 to 2.5 V for the temperature difference from 65 to 85 K was observed when a bismuth telluride thermoelectric couple (traditionally used in cooling technology) was used.

Go to article

Authors and Affiliations

Adam Ruciński
Artur Rusowicz
Download PDF Download RIS Download Bibtex

Abstract

The: PM2.5/PM10 ratio expresses the anthropogenic share in atmospheric dusl. Very high values or this ratio, i.e. high contribution or PM2.5 to PM10. have occurred recently in atmospheric air within European indusuializcd areas. The paper compiles results of three year pair wise measuring ofconcentrations or PM2.5 and PM2.5-PM10 and compares shares or PMM2.5 in PM10 al three urban background sites in Upper Silesia Poland I towns or Zabrze. Katowice and Częstochowa). At all the three local ions, the PM2.5/PM10 ratio nr daily conccntrations nr dust only occasionally differed considerably from the PM2.5/PM10 ratios for the seasonal and yearly concentrations that, in turn. did not differ from the PM2.5/PM10 ratios al urban sites in Europe.
Go to article

Authors and Affiliations

Krzysztof Klejnowski
Wioletta Rogula-Kozłowska
ORCID: ORCID
Andrzej Krasa
Download PDF Download RIS Download Bibtex

Abstract

This paper presents the results of experimental research regarding the determination of the flow characteristics of the compressor of an automotive turbocharger with a plastic rotor disc. The disc was manufactured using the 3D printing technology called the multijet printing, which allows complex geometries to be printed with high precision. Currently, in addition to speeding up the manufacturing processes and reducing their costs, 3D printing technologies are increasingly seen as standard tools that can be used in the design and optimization of machine parts. This article is a continuation of research on the possibility of applying additively manufactured elements in turbomachines. The experimental research was carried out at high rotational speeds (up to 110 000 rpm), using the automotive turbocharger with two different compressor rotors (i.e. one aluminum and one polymer). The first chapters of the paper discuss the preparation stage of the research (i.e. the manufacture of the rotor, the test rig). Then, the experimental research and the flow characteristics are described. The results obtained for the two types of discs were compared with each other and the area of application of the additively manufactured rotor was determined. The rotor functioned properly in the range of tested operating parameters and the results obtained showed that the technology and material applied could be used in the optimization studies of the blade systems of high-speed fluid-flow machines.
Go to article

Bibliography

[1] Liaw C.Y., Guvendiren M.: Current and emerging applications of 3D printing in medicine. Biofabrication 9(2017), 2, 024102.
[2] Tejo-Otero A., Buj-Corral I., Fenollosa-Artés F.: 3D printing in medicine for preoperative surgical planning: A review. Ann. Biomed. Eng. 48(2020), 2, 536– 555.
[3] Christensen A., Rybicki F.J.: Maintaining safety and efficacy for 3D printing in medicine. J. 3D Print. Med. 3(2017), 1–10.
[4] Kumar L.J., Nair C.K.: Current trends of additive manufacturing in the aerospace industry. In: Advances in 3D Printing and Additive Manufacturing Technologies (L.J. Kumar, D.I. Wimpenny, P.M. Pandey, Eds.) Springer, Singapore 2017, 39–54.
[5] Lee H., Jang Y., Choe J. K., Lee S., Song H., Lee J. P., Kim J.: 3D-printed programmable tensegrity for soft robotics. Sci. Robotics 5(2020), 45, eaay9024.
[6] Andrearczyk A., Baginski P., Klonowicz P.: Numerical and experimental investigations of a turbocharger with a compressor wheel made of additively manufactured plastic. Int. J. Mech. Sci. 178(2020), 105613.
[7] Kariz M., Sernek M., Obucina M., Kuzman M.K.: Effect of wood content in FDM filament on properties of 3D printed parts. Mater. Today Commun. 14(2018), 135–140.
[8] Andrearczyk A, Konieczny B, Sokołowski J.: Additively Manufactured Parts Made of a Polymer Material Used for the Experimental Verification of a Component of a High-Speed Machine with an Optimised Geometry – Preliminary Research. Polymers 13(2021), 1, 137.
[9] Cantrell J.T., Rohde S., Damiani D., Gurnani R., DiSandro L., Anton J., Ifju P.G.: Experimental characterization of the mechanical properties of 3D-printed ABS and polycarbonate parts. Rapid Prototyping J. 2017.
[10] Bassett K., Carriveau R., Ting D.K.: 3D printed wind turbines part 1: Design considerations and rapid manufacture potential. Sustainable Energy Technologies and Assessments 11(2015), 186–193.
[11] Constantinou P., Roy S.: A 3D printed electromagnetic nonlinear vibration energy harvester. Smart Mater. Struct. 25(2016), 9, 095053.
[12] Zhang X., Zhou H., Shi W., Zeng F., Zeng H., Chen G.: Vibration tests of 3D printed satellite structure made of lattice sandwich panels. AIAA J. 56(2018), 10, 1–5.
[13] Zeppei D., Koch S., Rohi A.: Ball bearing technology for passenger car turbochargers. MTZ worldwide 77(2016), 26–31.
[14] Idzior M., Karpiuk W., Bielinski M., Borowczyk T., Daszkiewicz P., Stobnicki P.: A concept of a turbocharger test stand. Combust. Engines 156(2014), 1, 30–40.
[15] Andrearczyk A., Baginski P., Zywica G.: Test stand for the experimental investigation of turbochargers with 3d printed components. Mechanics and Mechanical Engineering 22(2020), 2, 397–404.
[16] Andrearczyk A., Mieloszyk M., Baginski P.: Destructive tests of an additively manufactured compressor wheel performed at high rotational speeds. In: Proc. Int. Conf. Applied Human Factors and Ergonomics. Springer, Cham 2020, 117–123.
[17] Wisniewski P.P., Dykas, S., Zhang G.: Numerical studies of air humidity importance in the first stage rotor of turbine compressor. Arch. Thermodyn. 41(2020), 4, 223–234.
[18] MarSurf PS1, https://metrology.mahr.com/de/produkte/artikel/6910235-mobilesrauheitsmessgeraet- marsurf-ps-10-c2
[19] LabView software, https://www.ni.com/pl-pl/shop/labview.html
[20] TMD20, https://www.czaki.pl/produkt/przetwornik-pomiarowy-tmd-20-modbusrtu- rs-485-programowalny/
[21] Optel Thevon, https://www.optel-texys.com/en/152-g6-gpk-1-152.html
[22] Flowmeter EE741, https://www.epluse.com/en/products/flow-meter/flow-meterindustrial/ ee741/
[23] Peltron NPX pressure transducer, https://peltron.pl/produkty/przetwornikcisnienia- npx/
Go to article

Authors and Affiliations

Artur Andrearczyk
1

  1. Institute of Fluid Flow Machinery, Polish Academy of Sciences, Fiszera 14, 80-231 Gdansk, Poland
Download PDF Download RIS Download Bibtex

Abstract

Emission or air pollutants from fluidized bed furnaces is not as well known as emission from the traditional technologies of energetic combustion of fuels, the main source of air pollution in Poland. Boilers with circulating fluidized beds (CFB), working in Poland, proved their technical, technological economical and ecological advantages, gaining good perspective for their applications in municipal, industrial and national energetic - the more so. as they may be fueled with coal, coal slime, recycled wastes and bio-fuels. To fulfil the gap in knowledge concerning properties of dust and gases emitted to the atmospheric air from such boilers, measurements. analyses and investigations of emissions from four selected CFB boilers were performed. The examined CFB boilers belonged to the Polish heat generating plants Tychy, Chorzów ELCHO, Katowice and Jaworzno Ill (Department li). Emission of dust from cach of these four CFB boilers was measured, the dust granulometrie composition was determined and hazardous substances. such as polycyclic aromatic hydrocarbons (PAI-ls). compounds of trace elements (including heavy metals), polychlorinated dibenzodioxins (PCDD) and polychlorinated dibcnzofurans (PCDF), accumulated on the dust particles, were analysed. Emissions of sulphur dioxide. nitrogen dioxide. carbon monoxide, hydrogen chloride, hydrogen fluoride and volatile organic compounds (VOCs) were measured. The granulometrie composition of dust was determined by using a cascade impactor - this allowed avoiding errors due to dust coagulation occurring when measuring filters are used. The investigations, with their approach and methodology, are continuation of the authors' earlier investigations of emissions from combustion of coal. They present actual information on gas and dust emissions from the CBF boilers, allowing for complete evaluation of these emissions from the perspective of the environmental hazard. A synthetic result of the work is the factors for emission of total dust, PM2.5, PM I O, sulphur dioxide, nitrogen dioxide, carbon monoxide, hydrogen chloride, hydrogen fluoride, PAI-ls. YOCs, dioxins and furans from the CFB boilers, expressed in grams of emitted substance per I Mg of combusted fuel. All received results confirmed ecological advantages of combusting coal and coal slime in the CFB boilers- particularly, the low emissions of sulphur dioxide and nitrogen dioxide as well as minimal emissions of hydrogen fluoride, dioxins and heavy metals. Also, due to application of highly efficient electro-filters, the dust emission is low. The results revealed the effect of conditions of fuel combustion on emissions of some pollutants, especially PAIis and carbon monoxide.
Go to article

Authors and Affiliations

Jan Konieczyński
Bogusław Komosiński
Download PDF Download RIS Download Bibtex

Abstract

Ligninolytic enzymes are employed for the production of second-generation biofuel to minimize fuel crisis. Additionally, they play a crucial role in global carbon cycle and a variety of applications in food, agriculture, paper and textile industries. On a large scale production of ligninolytic enzymes, microorganisms can be cultured on lignocellulosic wastes. In the present study, proximate analysis including acid detergent lignin (ADL), acid detergent cellulose (ADC), acid detergent fi ber (ADF) and acid insoluble ash (AIA) were performed for Platanus orientalis (chinar), Bauhinia variegata (orchid tree), Pinus roxburghii (chir pine), wheat straw and wheat husk. Platanus orientalis was selected as substrate because of higher lignin contents for the production of ligninolytic enzymes by Aspergillus flavus. Solid State Fermentation was used and Response Surface Methodology was employed for optimizing various parameters and enzymes production. Maximum production was achieved at temperature 32°C, fermentation period 120 hours, pH 4.5, inoculums size 3.5 mL, substrate mesh size 80 mm, substrate size 7 g. Maximum purifi cation of laccase, manganese peroxidase (MnP) and lignin peroxidase (LiP) was achieved with 50%, 60% and 40% ammonium sulfate respectively and it was enhanced by gel filtration chromatography. Characterization of enzymes shows that Laccase has 35°C optimum temperature, 4.5 pH, 0.289 mM Km and 227.27 μM/ml Vmax. Manganese peroxidase has 30°C optimum temperature, 5.5 pH, 0.538 mM Km and 203.08 μM/ml Vmax. Lignin peroxidase has 30°C optimum temperature, 3 pH, 2 mM Km and 2000 µM/ml Vmax. Protein concentrations found in crude extracts and partially purified enzymes are respectively: laccase 1.78 and 0.71 mg/ml, MnP 1.59 and 0.68 mg/ml. LiP, 1.70 and 0.69 mg/ml.
Go to article

Authors and Affiliations

Jehangir Khan
1 3
Muahammad Javaid Asad
1
Raja Tahir Mahmood
2
Feeroza Hamid Wattoo
1
Tayyaba Zainab
1
Sidrah Nazir
1
Muhammad Basir Shah
4
Dawood Ahmed
5

  1. University Institute of Biochemistry and Biotechnology, PMAS-Arid Agriculture University Rawalpindi, Pakistan
  2. Department of Biotechnology, Mirpur University of Science and Technology (MUST), Mirpur-10250 (AJK), Pakistan
  3. Department of Biosciences, University of WAH, WAH Pakistan
  4. Department of Plant Breeding & Genetics, Balochistan Agriculture College Quetta, Pakistan
  5. Department of Medical Laboratory Technology, Haripur University, Haripur, KPK, Pakistan
Download PDF Download RIS Download Bibtex

Abstract

The paper deals with calibration of the simulation models of hydraulic part of an irrigation project. Calibrated simulation model can be used in design, reconstruction, enlargement or maintenance of the pressurized irrigation systems. Computer model of the water distribution system is a valuable tool which can assist engineers and planners in analyzing the hydraulic performance of water delivery systems. Calibration of the water distribution model consists in comparison of pressures and flows predicted with observed pressures and flows for known operating conditions (i.e., pump operation, tank levels, pressure-reducing valve settings), and adjustment of the input data for the model to improve agreement between observed and predicted values. In practice, given a set or sets of measured state variables, engineers apply trial and error techniques with their judgment to vary the parameters and accomplish this task. Trial and error techniques are tedious do not guarantee reasonable results. The paper introduces the methodology of determination of calibrated parameters automatically. Described methodology of calibration is based on optimizing procedures using the harmony search approach.

Go to article

Authors and Affiliations

Milan Čistý
Download PDF Download RIS Download Bibtex

Abstract

Batch dark fermentation of wheat straw and boiled potato wastes at volatile suspended solids (VSS) 5 g VSS/L are examined and compared. Investigations on dark fermentation of potatowastes and wheat straw were carried out at different pH and OFR (oxygen flow rate) values and inoculum pretreatment. The obtained hydrogen yield from waste potato was 70 mL/g VSS, while for hydrolysed wheat straw it amounted to 80 mL/g VSS. The optimum conditions for potato dark fermentation are acidic pH 6.0 and OFR 1.0 mL/h, while for the wheat straw, optimal conditions are pH 6.4 and OFR 4.6 mL/h. The comparison revealed a significant difference in hydrogen production due to the type of substrate, inoculum stressing and DF conditions applied.
Go to article

Bibliography

Achinas S., Li Y., Achinas V., Euverink G.J.W., 2019. Biogas potential from the anaerobic digestion of potato peels: Process performance and kinetics evaluation. Energies, 12, 2311. DOI: 10.3390/en12122311.
Aly S.S., Imai T., Hassouna M.S., Kim Nguyen D.M., Higuchi T., Kanno A., Yamamoto K., Akada R., Sekine M., 2018. Identification of factors that accelerate hydrogen production by Clostridium butyricum RAK25832 using casamino acids as a nitrogen source. Int. J. Hydrogen Energy, 43, 5300–5313. DOI: 10.1016/j.ijhydene.2017.08.171.
Bartacek J., Zabranska J., Lens P.N.L., 2007. Developments and constraints in fermentative hydrogen production. Biofuels, Bioprod. Biorefin., 1, 201–214. DOI: 10.1002/bbb.17.
Bundhoo Z.M.A., 2019. Potential of bio-hydrogen production from dark fermentation of crop residues: A review. Int. J. Hydrogen Energy, 44, 17346–17362. DOI: 10.1016/j.ijhydene.2018.11.098.
Chaganti S.R., Kim D.H., Lalman J.A., 2012. Dark fermentative hydrogen production by mixed anaerobic cultures: Effect of inoculum treatment methods on hydrogen yield. Renewable Energy, 48, 117–121. DOI: 10.1016/j.renene.2012.04.015.
Chi C.H., Chen K.W., Huang J.J., Chuang Y.C., Wu M.H., 1995. Gas composition in Clostridium septicum gas gangrene. J. Formos. Med. Assoc., 94, 757–759.
De Cicco A., Jeanty J.-C., 2017. The EU potato sector – statistics on production, prices and trade – Statistics Explained. Statistic Explained. Available at: https://ec.europa.eu/eurostat/statistics-explained/index.php?title= The_EU_potato_sector_-_statistics_on_production,_prices_and_trade.
Dessě P., Lakaniemi A.M., Lens P.N.L., 2017. Biohydrogen production from xylose by fresh and digested activated sludge at 37, 55 and 70 °C. Water Res., 115, 120–129. DOI: 10.1016/j.watres.2017.02.063.
Gallipoli A., Braguglia C.M., Gianico A., Montecchio D., Pagliaccia P., 2020. Kitchen waste valorization through a mild-temperature pretreatment to enhance biogas production and fermentability: Kinetics study in mesophilic and thermophilic regimen. J. Environ. Sci., 89, 167–179. DOI: 10.1016/j.jes.2019.10.016.
Garcia-Bernet D., Steyer J.-P., Bernet N., 2017. Traitement anaérobie des effluents industriels liquides Traitement anaérobie des effluents industriels liquides. Techniques de l’Ingénieur, Réf : J3943 v2.
García Depraect O., Muńoz R., van Lier J.B., Rene E.R., Diaz-Cruces V.F., León Becerril E., 2020. Three-stage process for tequila vinasse valorization through sequential lactate, biohydrogen and methane production. Bioresour. Technol., 307, 123160. DOI: 10.1016/j.biortech.2020.123160.
Han W., Ye M., Zhu A.J., Zhao H.T., Li Y.F., 2015. Batch dark fermentation from enzymatic hydrolyzed food waste for hydrogen production. Bioresour. Technol., 191, 24–29. DOI: 10.1016/j.biortech.2015.04.120.
Hawkes F.R., Hussy I., Kyazze G., Dinsdale R., Hawkes D.L., 2007. Continuous dark fermentative hydrogen production by mesophilic microflora: Principles and progress. Int. J. Hydrogen Energy, 32, 172–184. DOI: 10.1016/j.ijhydene.2006.08.014.
Hernández C., Alamilla-Ortiz Z.L., Escalante A.E., Navarro-Díaz M., Carrillo-Reyes J., Moreno-Andrade I., Valdez- Vazquez I., 2019. Heat-shock treatment applied to inocula for H2 production decreases microbial diversities, interspecific interactions and performance using cellulose as substrate. Int. J. Hydrogen Energy, 44, 13126– 13134. DOI: 10.1016/j.ijhydene.2019.03.124.
Kumar G., Bakonyi P., Periyasamy S., Kim S.H., Nemestóthy N., Bélafi-Bakó K., 2015. Lignocellulose biohydrogen: Practical challenges and recent progress. Renewable Sustainable Energy Rev., 44, 728–737. DOI: 10.1016/j.rser. 2015.01.042.
Laurinavichene T.V., Belokopytov B.F., Laurinavichius K.S., Tekucheva D.N., Seibert M., Tsygankov A.A., 2010. Towards the integration of dark- and photo-fermentative waste treatment. 3. Potato as substrate for sequential dark fermentation and light-driven H2 production. Int. J. Hydrogen Energy, 35, 8536–8543. DOI: 10.1016/j.ijhydene.2010.02.063.
Leszczyński, W., 2000. Jakość ziemniaka konsumpcyjnego. Żywność, Nauka, Technologia, Jakość, Supl., 4(25), 5–27.
Li Y., Zhang Q., Deng L., Liu Z., Jiang H., Wang F., 2018. Biohydrogen production from fermentation of cotton stalk hydrolysate by Klebsiella sp. WL1316 newly isolated from wild carp (Cyprinus carpio L.) of the Tarim River basin. Appl. Microbiol. Biotechnol., 102, 4231–4242. DOI: 10.1007/s00253-018-8882-z.
Moriarty K., 2013. Feasibility study of anaerobic digestion of food waste in St. Bernard, Louisiana. A study prepared in partnership with the Environmental Protection Agency for the RE-Powering America’s Land Initiative: Siting renewable energy on potentially contaminated land and mine sites. National Renewable Energy Laboratory (NREL), Technical Report, NREL/TP-7A30-57082. DOI: 10.2172/1067946.
Nasirian N., Almassi M., Minaei S., Widmann R., 2011. Development of a method for biohydrogen production from wheat straw by dark fermentation. Int. J. Hydrogen Energy, 36, 411–420. DOI: 10.1016/j.ijhydene.2010.09.073.
Paillet F., Maron, A., Moscovi, R., Steyer J.P., Tapia-Venegas E., Bernet N., Trably E., 2019. Improvement of biohydrogen production from glycerol in micro-oxidative environment. Int. J. Hydrogen Energy, 44, 17802– 17812. DOI: 10.1016/j.ijhydene.2019.05.082.
Patel A.K., Debroy A., Sharma S., Saini R., Mathur A., Gupta R., Tuli D.K., 2015. Biohydrogen production from a novel alkalophilic isolate Clostridium sp. IODB-O3. Bioresour. Technol., 175, 291–297. DOI: 10.1016/j.biortech.2014.10.110.
Sekoai P.T., Ayeni A.O., Daramola M.O., 2019. Parametric optimization of biohydrogen production from potato waste and scale-up study using immobilized anaerobic mixed sludge. Waste Biomass Valorization, 10, 1177–1189. DOI: 10.1007/s12649-017-0136-2.
Si B.C., Li J.M., Zhu Z.B., Zhang Y.H., Lu J.W., Shen R.X., Zhang C., 2016. Continuous production of biohythane from hydrothermal liquefied cornstalk biomass via twostage highrate anaerobic reactors. Biotechnol. Biofuels, 9, 254. DOI: 10.1186/s13068-016-0666-z.
Słupek E., Kucharska K., Ge˛bicki J., 2019. Alternative methods for dark fermentation course analysis. SN Appl. Sci., 1, 469. DOI: 10.1007/s42452-019-0488-2.
Sołowski G., Konkol I., Cenian A., 2019a. Perspectives of hydrogen production from corn wastes in Poland by means of dark fermentation. Ecol. Chem. Eng. S, 26, 255–263. DOI: 10.1515/eces-2019-0031.
Sołowski G., Konkol, I., Hrycak B., Czylkowski D., 2019b. Hydrogen and methane production under conditions of anaerobic digestion of key-lime and cabbage wastes. Agritech, 39(3), 243–250. DOI: 10.22146/agritech.35848.
Sołowski G., Konkol I., Cenian A., 2020a. Production of hydrogen and methane from lignocellulose waste by fermentation. A review of chemical pretreatment for enhancing the efficiency of the digestion process. J. Cleaner Prod., 267, 121721. DOI: 10.1016/j.jclepro.2020.121721.
Sołowski G., Konkol I., Cenian A., 2020b. Methane and hydrogen production from cotton waste by dark fermentation under anaerobic and micro-aerobic conditions. Biomass Bioenergy, 138, 105576. DOI: 10.1016/j.biombioe.2020.105576.
Woodward J., Orr M., Cordray K., Greenbaum E., 2000. Enzymatic production of biohydrogen. Nature, 405, 1014–1015. DOI: 10.1038/35016633.
Go to article

Authors and Affiliations

Gaweł Sołowski
1
Izabela Konkol
1
Marwa Shalaby
2
Adam Cenian
1

  1. Institute of Fluid-Flow Machinery Polish Academy of Sciences, Physical Aspects of Ecoenergy Department, 14 Fiszera St., 80-231 Gdańsk, Poland
  2. National Research Center in Cairo, Department of Chemical Engineering and Pilot Plant, El Bijouth St., Dokki, Cairo, Egypt 12622
Download PDF Download RIS Download Bibtex

Abstract

The composite materials as FRP (Fiber Reinforced Polymers), which are characterized by benefits resulting from the combination of high strength reinforcement (as carbon, glass, steel or aramid fibers) with synthetic matrix are increasingly used to reinforce existing structures. Reinforcing System as FRCM (Fibre Reinforced Cementitious Matrix), which includes, among others, Ruredil X Mesh Gold System, is much less commonly used. However, the uniform and practical methods for calculating composite reinforced structures are not determined. Especially when considering the real conditions of structure exploitation, which requires further research in this field. In the paper the initial loading level influence on the efficiency of reinforced concrete beams strengthen using system Ruredil X Mesh Gold was investigated.

Go to article

Authors and Affiliations

Z. Blikharskyy
K. Brózda
J. Selejdak
Download PDF Download RIS Download Bibtex

Abstract

The variability of the mean annual air temperature and precipitation totals in three periods: 1848–2010, 1951–2010 and 1981–2010 was investigated in the large Warta River basin, being the area with lowest rainfall in Poland. For the purposes of research, nine meteorological stations with the longest measurement series were selected. Air temperature increase in this river basin was similar than in neighbouring countries. In the last 30 years this trend kept increasing. The precipitation in the whole studied period was slightly increasing in the northern part of the Warta River basin, but decreasing in the southern part. The mean annual precipitation totals in the catchment area did not change visible. In the period 1981–2010, the precipitation totals show a small increase in the winter and spring and a decrease in summer. A negative influence of this climate change was not visible in the Warta River discharge. The main objectives of this study were the collection long-term records of air temperature and precipitation in the Warta River basin, and the statistical analysis of climate variability.

Go to article

Authors and Affiliations

Piotr Ilnicki
Ryszard Farat
Krzysztof Górecki
ORCID: ORCID
Piotr Lewandowski
Download PDF Download RIS Download Bibtex

Abstract

Upper Cretaceous calcareous nannoplankton recycled into the Pliocene Pecten Conglomerate of Cockburn Island (Antarctic Peninsula) provide a paleontological record of Upper Cretaceous sedimentary sequences in the James Ross Basin. The calcareous nannofossil assemblage comprises nearly 40 taxa and is dominated by Campanian-Maestrichtian species. The investigated assemblage shares some features with the southern high-latitude contemporaneous calcareous nannofossil assemblages from outcrops on adjacent Seymour (Marambio) Island and many with deep-sea drilling sites in the circum-Antarctic region.

Go to article

Authors and Affiliations

Elżbieta Gaździcka
Andrzej Gaździcki

This page uses 'cookies'. Learn more