Search results

Filters

  • Journals
  • Authors
  • Keywords
  • Date
  • Type

Search results

Number of results: 7
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

In these times of the climate crisis surrounding us, the improvement of technologies responsible for the emission of the largest amounts of greenhouse gases is necessary and increasingly required by top-down regulations. As the sector responsible to a large extent for global logistics and supply chains, the fuel sector is one of the most studied in terms of reducing its harmful impact. The development of the next generations of fuels and biofuels, produced by companies using increasingly modern, cleaner and sustainable technologies, is able to significantly reduce the amount of greenhouse gases released into the atmosphere. In this case, the most effective solution seems to be the use of closed loops. Due to their low, often zero emission balance and the possibility of using waste to produce materials that can be reused, a circular economy is used in many sectors of the economy, while ensuring the emission purity of technological processes. One of the innovative solutions proposed in recent years is the installation created as part of the BioRen project, implemented under the Horizon 2020 program. The cooperation of European institutes with companies from the SME sector has resulted in the creation of an experimental cycle of modern technologies for the production of second-generation biofuels. The project involves the processing of municipal solid waste into second-generation drop-in biofuels. The entire process scheme assumes, in addition to the production of biofuels, the processing of inorganic fractions, the production of carbon material for the production of thermal energy, and the simultaneous treatment of wastewater.
Go to article

Authors and Affiliations

Piotr Jan Plata
1
ORCID: ORCID
Agnieszka Nowaczek
2
ORCID: ORCID

  1. Chemistry Department, Warsaw University of Technology, Warsaw, Poland
  2. Mineral and Energy Economy Research Institute, Polish Academy of Sciences, Kraków, Poland
Download PDF Download RIS Download Bibtex

Abstract

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.

Go to article

Authors and Affiliations

Zeynel Başibüyük
ORCID: ORCID
Ilkay Kaydu Akbudak
ORCID: ORCID
Meltem Gürbüz
ORCID: ORCID
Download PDF Download RIS Download Bibtex

Abstract

Boiling produces vapor with a phase change by absorbing a consistent amount of heat. Experimentation and modeling can help us better understand this phenomenon. The present study is focused on the heat transfer during the nucleate pool boiling of refrigerant R141b on the surface of a horizontal copper tube. The results of the experiment were compared with four correlations drawn from the literature, and the critical heat flux was examined for different pressures and also compared with the predicted values. Simulating boiling with two-phase models allowed us to infer the plot of the temperature distribution around the tube and compared it to results from other work.
Go to article

Bibliography

[1] V.K. Dhir. Nucleate and transition boiling heat transfer under pool and external flow conditions. International Journal of Heat and Fluid Flow, 12(4):290–314, 1991. doi: 10.1016/0142-727X(91)90018-Q.
[2] I.L. Pioro, W. Rohsenow, and S.S. Doerffer. Nucleate pool-boiling heat transfer. I: review of parametric effects of boiling surface. International Journal of Heat and Mass Transfer, 47(23):5033–5044, 2004. doi: 10.1016/j.ijheatmasstransfer.2004.06.019.
[3] T. Baki and A. Aris. Etude expérimentale du transfert de chaleur lors de l’ébullition en vase du R141b. (Experimental study of heat transfer during the pool boiling of R141b). Communication Science & Technology, No. 11, July 2012 COST (in French).
[4] T. Baki, A. Aris, and A. Guessab. Impact du diamètre extérieur d’un tube horizontal lors de l’ébullition en vase. (Impact of the outside diameter of a horizontal tube during pool boiling). In 12th Mechanical Congress, 21-24 April 2015, Casablanca, Marocco (in French).
[5] T. Baki, A. Aris, and M. Tebbal. Proposal for a correlation raising the impact of the external diameter of a horizontal tube during pool boiling. International Journal of Thermal Sciences, 84:293–299, 2014. doi: 10.1016/j.ijthermalsci.2014.05.023.
[6] T. Baki. Etude expérimentale et simulation de l’ébullition à l’extérieur d’un tube horizontal. (Experimental study and simulation of boiling outside a horizontal tube). Ph.D. Thesis, University of Sciences and Technology of Oran Mohamed Boudiaf (USTO-MB), Oran, Algeria. (in French).
[7] T. Baki. Ebullition à l’Extérieur d’un Tube Horizontal, Comparaison de Corrélations. (Boiling outside a horizontal tube, comparison of correlations). In National Congress on Energies and Materials (CNEM), December 17-18, 2018, Naâma Algeria (in French).
[8] T. Baki. Ebullition à l’extérieur d’un Tube Horizontal à des Pressions sous Atmosphérique, Comparaison de Corrélations. (Boiling outside a horizontal tube under atmospheric pressures, comparison of correlations). In: 1st International Symposium on Materials, Energy and Environment – MEE'2020, January 20-21, 2020, El Oued, Algeria (in French).
[9] T. Baki. Survey on the nucleate pool boiling of hydrogen and its limits. Journal of Mechanical and Energy Engineering, 4(2):157–166, 2020. doi: 10.30464/jmee.2020.4.2.157.
[10] S. Deb, S. Pal, D.Ch. Das, M. Das, A.K. Das, and R. Das. Surface wettability change on TF nanocoated surfaces during pool boiling heat transfer of refrigerant R-141b. Heat and Mass Transfer, 56(12):3273–3287, 2020. doi: 10.1007/s00231-020-02922-w.
[11] O. Khliyeva, V. Zhelezny, T. Lukianova, N. Lukianov, Yu. Semenyuk, A.L.N. Moreira, S.M.S. Murshed, E. Palomo del Barrio, and A. Nikulin. A new approach for predicting the pool boiling heat transfer coefficient of refrigerant R141b and its mixtures with surfactant and nanoparticles using experimental data. Journal of Thermal Analysis and Calorimetry, 142(6):2327–2339, 2020. doi: 10.1007/s10973-020-09479-0.
[12] M.Y. Abdullah, Prabowo, and B. Sudarmanta. Analysis degrees superheating refrigerant R141b on evaporator. Heat and Mass Transfer, 1–13, 2020. doi: 10.1007/s00231-020-02963-1.
[13] T. Li, X. Wu, and Q. Ma. Pool boiling heat transfer of R141b on surfaces covered copper foam with circular-shaped channels. Experimental Thermal and Fluid Science, 105:136–143, 2019. doi: 10.1016/j.expthermflusci.2019.03.015.
[14] W.M. Rohsenow. A method of correlating heat transfer data for surface boiling of liquids. Technical Report No. 5.MIT, USA, 1952.
[15] D.A. Labuntsov. Heat transfer problems with nucleate boiling of liquids. Thermal Engineering, 19(9):21–28, 1973.
[16] M.G. Cooper. Saturation nucleate pool boiling – a simple correlation. In: H.C. Simpson et al. (eds.), First U.K. National Conference on Heat Transfer, The Institution of Chemical Engineers Symposium Series, Volume 2.86, pages 785–793, Pergamon, 1984. doi: 10.1016/B978-0-85295-175-0.50013-8.
[17] K. Cornwall and J.G. Einarsson. Peripheral variation of heat transfer under pool boiling on tubes. International Journal of Heat and Fluid Flow, 4(3):141–144, 1983. doi: 10.1016/0142-727X(83)90059-0.
[18] P.R. Dominiczak and J.T. Cieśliński. Circumferential temperature distribution during nucleate pool boiling outside smooth and modified horizontal tubes. Experimental Thermal and Fluid Science, 33(1):173–177, 2008. doi: 10.1016/j.expthermflusci.2008.07.007.
[19] K. Fukuda and A. Sakurai. Effects of diameters and surface conditions of horizontal test cylinders on subcooled pool boiling CHFs with two mechanisms depending on subcooling and pressure. In: 12th International Heat Transfer Conference, Grenoble, France, August 18–23, 2002. doi: 10.1615/IHTC12.4530.
[20] S.G. Kandlikar. Critical heat flux in subcooled flow boiling – An assessment of current understanding and future directions for research. Multiphase Science and Technology, 13(3):207–232, 2001. doi: 10.1615/MultScienTechn.v13.i3-4.40.
[21] S.S. Kutateladze. On the transition to film boiling under natural convection. Kotloturbostroenie, 3:152–158, 1948.
[22] W.M. Rohsenow, J.P. Hartnett, and Y.I. Cho (eds). Handbook of Heat Transfer, 3 edition, Mc Graw-Hill, 1998.
Go to article

Authors and Affiliations

Touhami Baki
1
ORCID: ORCID
Abdelkader Aris
2
Mohamed Tebbal
1

  1. Faculty of Mechanics, Gaseous Fuels and Environment Laboratory, University of Sciences andTechnology of Oran Mohamed Boudiaf (USTO-MB), El Mnaouer, Oran, Algeria.
  2. ENP. Oran, Laboratoire de Recherche en Technologie de Fabrication Mécanique, Algeria
Download PDF Download RIS Download Bibtex

Abstract

Melanoma is a highly malignant neoplasm with the most typical primary locations in the skin and eyeball and rarely reported in the other organs, including the gallbladder. More commonly metastases of melanoma of various primary sites to the gallbladder are observed. However, generally melanoma of the gallbladder is a rare entity with only 217 cases reported in the literature up to date. The paper summarizes knowledge on epidemiology, symptoms, laboratory and imaging findings, morphology, treatment options, and outcome of patients with both primary and metastatic melanoma to the gallbladder.
Go to article

Authors and Affiliations

Paweł Bojar
1 2
Franciszek Burdan
3 4
Lech Wronecki
1
Justyna Szumiło
1

  1. Department of Clinical Pathomorphology, Medical University of Lublin, Lublin, Poland
  2. Department of Pathomorphology, Beskid Oncology Centre — John Paul II Memorial City Hospital in Bielsko-Biala, Bielsko-Biała, Poland
  3. Department of Human Anatomy, Medical University of Lublin, Lublin, Poland
  4. epartment of Radiology, St Johns’ Cancer Center, Lublin, Poland
Download PDF Download RIS Download Bibtex

Abstract

This paper discusses the contribution of linguistics to theology, taking the specific example of L.-M. Chauvet’s thought. First, the critique of language as a tool is analyzed. According to Chauvet, language can no longer be considered as a tool, but as a mediation, understood as a “matrix” or environment ( milieu). Linguistic mediation is thus explained from the conceptual perspective of symbol and symbolic order: human subjectivity is inseparable from language, and language has a symbolic structure. Theological reflection follows the concept of mediation and symbol as an important anthropological fact. Faith, then, involves rejecting the illusion of direct contact with God and accepting the mediation of the Church and the sacraments as a process of “accepting ourselves” as children of God and accepting one another in Christ as brothers.
Go to article

Authors and Affiliations

Paweł OFM Sambor
1
ORCID: ORCID

  1. Pontificia Università Antonianum, Roma
Download PDF Download RIS Download Bibtex

Abstract

These remarks are to be considered as a voice in the discussion not only on the historical role of the Catholic Church in culture but also on mistakes committed by its Magisterium of the Catholic Church such as absolutism, globalism, and intolerance. Certainly it can be called otherwise. The key issue is however at how we call it but if we consider it as major mistakes and if yes if we seek for such an explanation that will actually is an excuse. This is the case in the example of often recalled in these remarks “The history of the Catholic Church” by Marian Banaszak. I do represent another view than this author. Also not just than Banaszak himself but other authors as well who blame for the failures of Catholicism (including the decline of its decisive social role) all those but not the ones who make the key decisions within the Church.
Go to article

Authors and Affiliations

Zbigniew Drozdowicz
1
ORCID: ORCID

  1. Instytut Kulturoznawstwa, Uniwersytet im. Adama Mickiewicza, Poznań

This page uses 'cookies'. Learn more