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Effect of Surface Passivation on CdxNi1-xS Thin Films Embedded with Nickel Nanoparticles

Author(s): Cliff Orori Mosiori / Language(s): English Issue: 08/2017

Certain treatments done to binary CdS, such as incorporating Ni onto CdS produces ternary thin films may cause major optical parameters that have a number of applications including for solar cell device fabrication. In this paper, we report on the effect of surface passivation on the band gap and other related optical properties of CdNiS thin films. Thin films for CdxNi1-xS were prepared on glass substrates by chemical solution method. Effects of surface passivation and variation of the volume of nickel ions on the optical properties CdS hence obtaining CdxNi1-xS thin films was investigated. It was observed that the thin films hard an average Transmittance above 68 %, with reflectance below 25 % across UV-VIS-NIR region. A plot of (αhν) 2 versus hν gave energy band gap between 2.55–3.49 eV for as-grown samples and 2.82–3.50 eV for annealed samples. The passivated samples had band gap energy values within the range 2.85–3.12 eV. It was concluded that an increase in concentration of Cd2+ and Ni2+ ions in the reaction led to an increase the band gap while optical conductivity ranged between 3.78 1011–2.40 1012 S-1.

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Розробка інформаційного забезпечення автоматизованої системи моніторингу стану промислової безпеки газотранспортної системи

Author(s): Ruslan Skrynkovskyy,Solomiya Leskіv,Volodymyr Yuzevych / Language(s): Ukrainian Issue: 08/2017

The purpose of the article is to developing the information security of the automated system for monitoring the state of industrial safety of the gas transportation system within the framework of the safety management system, which will enable timely and objective detection of adverse accident hazards (hazardous events) and taking the necessary specific measures to eliminate them and operate the gas transport system safely. It is proved that the basis of the information provision of the automated system for monitoring the state of the industrial safety of the gas transmission system is a methodology that includes the following basic procedures: identifying hazards; qualitative and quantitative assessment of emergencies; establishing of unacceptable (unallowable) risks and their introduction to the information base (register) of unacceptable risks of objects of the gas transportation system; comprehensive assessment and certification of the state of industrial safety of objects of the gas transportation system; identification of effective, productive (efficient) risk management measures. The prospect of further research in this area is the development and implementation of an automated system for monitoring the state of industrial safety of the objects of the gas transmission system based on the results of the research (of the submitted information provision).

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Türkiye’de Kurulması Düşünülen Nükleer Santrallere İlişkin Öğretim Elemanlarının Görüşlerinin Değerlendirilmesi (Sinop Örneklemi)

Author(s): İrfan Mukul / Language(s): Turkish Issue: 48/2015

There are several dimensions and examples of the state of the markets of Turkey entering into the domination of the international capital. One of these is, no doubt, the fact that the nuclear power plants are allowed to be built. Depending on the economic developments in the world, the attempts to build nuclear power plants in Turkey almost go hand in hand with Turkey’s keeping pace with such developments. Although the Nuclear Power Plant building attempts date back to the post-World War II as in the other examples in the world, it can be stated that today’s neoliberal economic developments have made the process visible. In order to unveil this situtation and test the assumptions put forward, we asked the opinions of the teaching staff working for Sinop University concerning the Nuclear Power Plants planned to be built in Sinop. We have already known that the result we obtain is closely related to the answers to the questions for whom, for what puspose, and how the world resources, the solution of the problem, should be used. Therefore, we asked the participants the questions concerned. The answers to the questions are significant in revealing whether they are in favour of the fact that a couple of people ruthlessly exploit the world resources to safegurar their own interests , or that the earth, which belongs to all living creatures equally, should be arranged for their benefits. Majority of the teaching staff taking part in the nuclear power plant discussion allowed us to reach the arguments which mean capitalism and ecology cannot coexist.

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Удосконалення нормативних вимог щодо забезпечення якості підземних газопроводів в умовах корозійної втоми

Author(s): Volodymyr Yuzevych,Ruslan Skrynkovskyy,Mykola Mykyychuk / Language(s): Ukrainian Issue: 09/2017

The article develops recommendations for improvement of normative documents concerning the quality of underground metal pipelines (gas pipelines) under conditions of fatigue and the impact of an aggressive environment, taking into account cathodic (electrochemical) protection. It is established that the basis of information provision of normative documents is the method which includes the following main criteria: the value of the minimum current density of cathode protection; minimum security potential; maximum protective potential, minimal displacement of protective potential; strength criteria of pipe material; criteria of strength of phase layer between the metal and the coating; the strength of the metal in the defect of the insulation coating. It has been found out that the system "metal pipe - insulating dielectric coating" is characterized by such basic procedures as: identification of hazards; various variants of load asymmetry; evaluation of the boundary and optimal values of potentials and currents for the system of cathodic protection of the pipeline. The prospect of further research in this area is determination of the complex indicator of quality and reliability of the linear part of underground main gas pipelines on the basis of research results (submitted information support).

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$Studies on Cd1Se0.6Te0.4 Thin Films by Spectroscopic and Diffractometer Characterization$

Studies on Cd1Se0.6Te0.4 Thin Films by Spectroscopic and Diffractometer Characterization

Author(s): Cliff Orori Mosiori,Duke Ateyh Oeba / Language(s): English Issue: 09/2017

Cadmium selenide tellurium is a compound containing cadmium, tellurium and selenium elements forming a combined solid. Hall measurements suggest that it is an n-type semiconductor. Related optical studies indicate that is transparent to infra-red radiation. Structural studies clearly show that it has a wurtzite, sphalerite crystalline forms. Cadmium is a toxic heavy metal, and selenium is only toxic in large amounts or doses. By this toxicity, cadmium selenide is a known to be carcinogen to humans; however, this does not stop investigating it for optoelectronic applications. Current research has narrowed down to investigating cadmium selenide when in the form of nanoparticles. Cadmium selenide finds applications has found applications in opto-electronic devices like laser diodes, biomedical imaging, nano-sensing, high-efficiency solar cells and thin-film transistors. By chemical bath deposition, Cd1Se0.6Te0.4 thin films were grown onto glass. Tellurium was gradually introduced as an impurity and its crystalline structure and optical properties were investigated by XRD and UV-VIS spectroscopy. The main Cd1Se0.6Te0.4/glass characteristics were correlated with the conditions of growing and post-growth treatment and it was found out that films were homogeneous films with controllable thickness onto the glass substrate and suitable for n-type “sandwich” heterostructures applications. Comparison of the intensities of equivalent reflexions provided a test for the internal consistency of the measurements. Equivalent reflexions in two specimens differed on average by 1.4 % and 0.6% from the mean measured intensity, attesting to the high internal consistency of measurements from extended-face crystals. By comparison from data obtained from all samples showed their average deviation from the mean to be 0.9 %.

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Effects of Acid Treatment on the SEM-EDX Characteristics of Kaolin Clay

Author(s): Shehu Yahaya,Suzi Salwah Jikan,Nur Azam Badarulzaman,Ajiya Dahiru Adamu / Language(s): English Issue: 09/2017

Raw kaolin was refluxed by sulphuric acid in variable concentrations of 2 M, 4 M, 6 M and 8 M. The morphology and elemental compositions of the acid-leached kaolin were analyse by Field Scanning Electron Microscopy (FESEM) and Energy Dispersive X-ray analysis (EDX) respectively. The disintegration and leaching of Al3+ ions of the clay are determined by FESEM studies. The acid treatment increases the silicon content and decreases aluminium content as revealed by EDX analysis. The leaching of Al3+ ions increases with gradual increase in concentration of the acid. Therefore, kaolin reflux with acid at lower strength (2 M and 4 M) are more dispersed and more industrially useful than that which is treated at higher acid strength.

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Transformacja energetyczna w polskiej gminie. Skutki polityki lokalnej opartej o odnawialne źródła energii na przykładzie Kisielic

Author(s): Jan Frankowski / Language(s): Polish Issue: 149/2017

The increasing role of renewable energy sources implies significant socio-economic changes at the local level. In Poland, a great importance in that area is attached to wind turbines and biofuel-based combined heat and power stations. Localization of these investments often leads to social conflicts. The aim of this study is to assess the consequences of local policy in Kisielice, which in the years 1998 to 2015 gave priority to RES development. Considering this problem from the perspective of the energy justice framework and the law on wind energy investments, a case study has been investigated. The case study consists of: (1) literature review, including nine interviews with the local authorities (2) statistical and spatial analysis (3) fieldwork in five villages located in the direct neighbourhood of wind energy turbines. The results show that long-term local energy policy in Kisielice, implemented with an intensity comparable to the German Energiewende, has met the most of social acceptance conditions. Support for RES in the villages susceptible to anthropogenic influence displays similar patterns to trends at the national level. However, the inhabitants have a sense of injustice resulting from the fact that only a small group obtains benefits from the use of wind turbines. According to the author’s opinion, a compromise between restrictive provisions of the law on wind energy investments and local community’s interests can only be based on creating the atmosphere of trust and partnership, as well as implementing mechanisms of direct compensations for negative external effects created by renewable installations.

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Efekty czasowe szoków na rynku energii elektrycznej: badania krajów UE, które przeszły transformację ustrojową

Author(s): Đorđe Borozan / Language(s): English Issue: 104/2017

This paper explores the time-series properties of the relative per capita electricity consumptionseries disaggregated by consumer sectors for the presence of a unit root for eleven post-transitionEU countries. To that end, the panel unit root tests without and with structural break(s) were usedcovering the period 2002–2013.The results of the former indicate that electricity consumption is the unit root process for eachsector, indicating that any shock thereto is likely to be permanent. The results of the latter supportthe non-stationary null for the majority of the countries and sectors under investigation, and alsopoint out that each country was exposed to at least one significant shock affecting some of theelectricity consumption variables. Thereby, the shocks will probably have permanent effects onthem, and their electricity consumption will be path-dependent. Consequently, there is little evidenceof convergence of post-transition EU countries to the single electricity market.

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Uprawnienia zbywalne do emisji gazów cieplarnianych jako innowacja finansowa

Author(s): Grażyna Borys,Wojciech Krawiec / Language(s): Polish Issue: 104/2017

Tradeable greenhouse gas discharge permits are the subject of the study since, by nature, theyrepresent the key component of the European emission trading scheme, whereas the purpose ofthe study is the identification and also the analysis of formal (legal) and non-formal reasons forapproaching trading permits as financial innovations of regional (European) range and local (national)range. The identification was conducted by presenting the essence of the discussed permitsand their brief characteristics, supported by the statistical elements from Polish auctions of GHGdischarge permits.

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PERSPEKTIVE I MOGUĆNOSTI TOPLIFIKACIJE GRADA GRAČANICE

Author(s): Hasan Mostarlić / Language(s): Bosnian Issue: 19/2005

U svakom gradu, industrijskom centru i naselju, za život i rad ljudi potrebna je toplotna energija za stambene i razne komunalne potrebe, te tehnološke procese u industriji.

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Chemical Composition and Particle Size Analysis of Kaolin

Author(s): Shehu Yahaya,Suzi Salwah Jikan,Nur Azam Badarulzaman,Ajiya Dahiru Adamu / Language(s): English Issue: 10/2017

The mineral and elemental composition, crystal structure and particle size distribution of kaolin clays have been determined to ascertain its industrial significance. The mineral composition is evaluated by X- Ray Fluorescence (XRF), crystalline structure by X-Ray Diffraction (XRD) and particle size distribution using low angle laser light scattering (LALLS) technique. The results shows the presence of eight elements expressed in percentages in form of their oxides as: SiO2, Al2O3, Fe2O3, MgO, CaO, K2O, TiO2 and P2O5. Five crystalline structures are revealed by XRD result. The particle size distribution shows that kaolin particles are mainly in the range of 25–35 µm, while few particles have size distribution varied between 0.4–0.75 μm. The report is found to be in agreement with other researchers.

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Synthesis and Characterization of Natural Sensitizers for Dye Sensitized Solar Cells

Author(s): Mohammed Isah Kimpa,Kasim Uthman Isah,Jibrin Alhaji Yabagi,Sulaiman Taufiq,Mohd Arif Bin Agam / Language(s): English Issue: 10/2017

Natural dyes of anthocyanin extract from flame tree flower (Delonix regia) and chlorophyll extract from pawpaw leaf (Carica papaya) were used as sensitizer to fabricate dye sensitized solar cell (DSSC). The photoelectrode were subjected to UV/Vis spectrophotometer to view their absorbability. The photo electrochemical performances of DSSCs obtained from I.V characteristics showed conversion efficiency, (ɳ) of 0.80 % for the dye extracts from flame tree flower (anthocyanine), with open-circuit voltage (VOC) of 0.5249 mV, short-circuit current density (Isc) of 44.6191 mA/m2 and Fill factor (FF) of 0.5837. Chlorophyll dyes extract from pawpaw leaf has VOC, Isc, FF and conversion efficiency, (ɳ) of 0.5249 mV, 16.5283 mA/m2, 0.5585 and 0.27 % respectively. The conversion efficiency for the mixed dyes (anthocyanin and chlorophyll) at ratio 1:2 is 0.23 % with VOC, Isc and FF of 0.5500 mV, 14.2750 mA/m2 and 0.5451 respectively, while the dye mixture at ratio 1:4 achieved VOC of 0.5249 mV, Isc of 18.4941 mA/m2, FF of 0.5206 and conversion efficiency (ɳ) of 0.26 %. Anthocyanine from flame tree flower dye extract had the higher conversion efficiency of 0.8 % which could be better in term of application in dye solar cell.

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Determination of Planck’s Constant using Light Emitting Diodes

Author(s): Cliff Orori Mosiori,Duke Ateyh Oeba,Reuben Shikambe / Language(s): English Issue: 10/2017

Planck’s constant is named after Max Planck, a nineteenth-century physicist who first described it by relating it as E=hw where symbols have their usual meanings. It is a relationship used when comparing a quantum of energy absorbed to that emitted during electron transitions which can be extended to emission by light-emitting diodes. The purpose of this study was to determine Planck’s constant using the energy needed to excite free electrons in a light emitting diode. When a light-emitting diode is switched on, electrons recombine with holes within and release energy in the form of photons which can be determined using energy band gaps of the semiconductor composite material used to fabricate the LED. Therefore, LEDs consist of a chip of doped semiconducting layers to create a p-n junction. In LEDs, current flows easily from the p-side to the n-side but not in the reverse from electrodes with different voltages. When an electron meets a hole, it is inhaled and it falls into lower energy level releasing energy in the form of a photon. Photon emissions take place when electrons return to a lower energy state. Therefore, electrons within a LED crystal are excited to a higher energy state and any radiation emitted depends on the p-n junction direct band gap. Depending on the materials used, LEDs emit radiation with energies corresponding to either near-infrared, visible, or near-ultraviolet light. In reality, a LED is designed to have a small area (approximately less than 1 mm2). In this work, an electric current was used to excite electrons and the corresponding energy was measured using a voltmeter. Planck’s constant was calculated by substituting the obtained frequency and energy from the voltmeter in the relationship, E = hw.

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Макро- та мікроскопічне дослідження впливу 2-феніл-3-карбетокси-4-диметиламінометил-5-оксибензофурану гідрохлориду (вінборону) на гастротоксичність ібупрофену за умов експериментального ревматоїдного артриту у щурів

Author(s): Fedir Hladkykh,Natali Stepaniuk,Sergii Vernygorodskyi / Language(s): Ukrainian Issue: 10/2017

It is known that besides a wide range of therapeutic effects, non-steroidal anti-inflammatory drugs have side effects such as gastroduodenotoxicity, hepatotoxicity, cardiotoxicity, nephrotoxicity, hematotoxicity, allergenicity, neurotoxicity, and others. We have proposed the use of Ukrainian antispasmodics with polytropic pharmacological properties of vinboron in order to prevent ulcerogenic action of ibuprofen.The conducted study showed that the combined use of ibuprofen and vinboron led to a weakening of the signs of gastrotoxicity of this antiflossistics. This was indicated by a significantly lower degree of lesion of the mucous membrane of the stomach - the ulcerous index was almost 10 times smaller than on the background of monotherapy and was, respectively, 0.10 and 0.97. The increase in body weight in rats with experimental rheumatoid arthritis in the 28th day of experiment with the combined use of ibuprofen and vinboron was twice as high as that of animals in the monotherapy group and was 16.3 ± 3.19%, respectively (95% CI: 10.0-22.5 %) relative to 1 day of the experiment. The stomach ulcers were noted only in 14.3% of animals, which is three times lower than on the background of ibuprofen monotherapy.

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Decarbonizing the European energy system: the SET-Plan actions in the industry and transport sectors

Author(s): Maria Kottari,Cristian Sales Agut,Jose A. Moya,Lois Brett,Carmen Moles,Francesco Dolci,Aliki Georgakaki,Evangelos Tzimas / Language(s): English Issue: 1-2/2017

All European citizens should have access to secure, sustainable and affordable energy. This is the primary objective of the Energy Union, one of the key priorities of the current Commission. This objective can only be achieved through a fundamental transformation of our energy system. In such a system, energy would be used efficiently in all economic sectors, low-carbon conversion technologies would generate electricity along with heating and cooling for homes and industries, and renewable fuels would be used for transport as an alternative to liquid hydrocarbons. This transformation of the energy system will bring additional benefits: the fight against climate change will become more effective and new business opportunities will be created, driven by the need for new services and technologies. The success of this transformation depends largely on the effective development and commercialization of low-carbon, low-cost and high-performance energy technologies and their integration into all facets of the energy system. To meet this challenge, research and innovation (R&I) has become one of the five priorities, or dimensions, of the Energy Union strategy. Placed at the core of the EU’s overall energy and climate policy since its launch, the SET-Plan this year reaches a milestone – its 10th anniversary. During this period, it has contributed to boosting low-carbon energy innovation by triggering an increased alignment between public and private, European and national research agendas. Technological roadmaps and strategic targets helped maintain a focus on priorities, while new structures and processes stimulated cooperation and the pooling of resources. During these ten years, the SET-Plan has been a reference point for Europe's R&I policies at the national and EU levels. The SET-Plan will also play a key role in the completion of the Energy Union, by supporting efforts to develop national energy and climate plans for the implementation of the Energy Union’s 5th dimension. The SET-Plan will continue to function as a cornerstone of Europe's energy system transformation to a low-carbon and sustainable, smarter energy system for the benefit of European society.

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Energy innovation needs a public, private and international boost

Author(s): David Turk / Language(s): English Issue: 1-2/2017

Despite growing recognition of the importance of energy innovation, global spending on energy research, development and demonstration (RD&D) has not risen over the past four years. Efforts by the public and private sectors also differ – the IEA data show that while governments spend more of their RD&D budgets on energy efficiency and renewables, the private sector spends a larger share on the oil, gas, networks and utilities sectors. Mission Innovation, the IEA’s Technology Collaboration Programs, and the EU SET Plan provide important opportunities to boost and maximize the benefits from energy innovation efforts.

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Slovak electric car pioneer: subsidies could help bring about tipping point

Author(s): Peter Badík / Language(s): English Issue: 1-2/2017

Slovakia produces one million cars per five million inhabitants making it the biggest car manufacturer per capita. Its auto industry generates12 per cent of GDP. It also produces and exports electric vehicles. But only a few hundred are to be seen on Slovak roads. The country does not seem to be embracing the e-mobility restructuring of the industry it depends on. Peter Badík is a pioneer of electric mobility in Slovakia and co-founded two electric vehicle service companies, Voltia and GreenWay. He is former director of the Slovak Electric Vehicle Association. He graduated from the Technical University of Žilina and the University of Economics in Bratislava.

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Now and then: why Hungarian wholesale electricity is still more expensive than the German

Author(s): Enikő Kácsor,András Mezősi / Language(s): English Issue: 1-2/2017

This article investigates possible explanations for the price difference between the Hungarian and German day-ahead wholesale electricity markets. It compares findings from a previous analysis on the 2011–2013 period (around the time when Hungary joined the CZ–SK market coupling) with those for January 2017, when unprecedented price spikes occurred in the region. It looks at the similarities and differences in past and present market behavior, analyzing the effect of different variables on the Hungarian market and the price difference between the two markets. The January analysis uses different methodologies from the previous study, which examined three years of available data, as the exceptionally high electricity prices lasted only for a few days in January.

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The evaluation of effective criteria on site selection for energy production units from cellulosic biomass in Iran

Author(s): Majid Azizi,Fatemeh Rahimi,Mohammad Amin Jonoobi,Mosen Ziaie / Language(s): English Issue: 2/2017

Both Analytical Hierarchy Process (AHP) and benefits, opportunities, costs and risks (BOCR) techniques were used successfully to evaluate the effective criteria on site selection for energy production unit development from cellulosic biomass in Iran. The results showed that the benefits criteria was at the first level while the initial cellulosic raw materials and opportunities with the aim of the local economy had the second position as the most important indices on site selection. In addition, third criterion has been introduced for the costs criteria (transportation cost) and social barriers by the experts. However, risks criteria which referred to instability of providing cellulosic raw materials is one of the less important effective indices on site selection to make energy production unit. The results illustrated that the economy and politics as two environmental effective factors affected on the site selection process generally.

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Modeling a Bandwidth of a Two-Level Independent Quantum Laser System States

Author(s): Cliff Orori Mosiori / Language(s): English Issue: 12/2017

An electromagnetic radiation is basically considered to be a transverse wave propagating through an accessible media whether it is an optical fibre or a thin film depending on its propagating conditions. In analyzing its propagation, utilized specific cross-section areas have become an important base of understanding its extinction parameters. The term cross-section in this work applies only to boundary conditions within which particles interact within electromagnetic spectra through absorption or scattering. In such small volume contextual framework, nanotechnology reconsiders scattering cross-section coefficients. In this work, two different degenerate states were modeled and analyzed using a developed model of a laser cavity containing a media of length, L, with a gain of, k, per unit length which were mirrored to represent the upper and a lower level manifolds inhomogeneous broadening Stark levels respectively. The model developed created an impression that a laser medium is a coherent ensemble of particles or atoms whose bandwidth depends on how a laser is constructed.

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