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Ecosystem destruction is one of today’s significant challenges due to fast industrialisation and an increasing population. It takes several years for solid trash, such as plastic bottles and super-market bags, to decompose in nature. In addition, plastic disposal techniques such as landfilling, reuse, and incineration pose significant threats to human health and the environment. In this paper, we investigated whether the impact of mixing biodiesel with waste oil from recycled plastic on the resulting fuel mixture’s yields better physical and chemical properties. Consequently, pyrolysis is one of the most advantageous and practical waste disposal methods as it is both environmentally benign and efficient. Pyrolysis is the high-temperature thermal breakdown of solid waste to produce pyrolytic oil. The pyrolytic (plastic) oil produced is converted to a hydrocarbon-rich pyrolytic fuel. Similar to diesel and gasoline, pyrolytic fuel has the same calorific value. Internal combustion engines may operate on pyrolytic fuel without suffering a performance reduction. Researchers examined engine performance and exhaust pollutants. The research discovered that the engine could operate on plastic pyrolysis fuel at full load, enhance brake thermal efficiency by 6–8%, and lower UBHC and CO emissions; however, nitrous oxide (NOx) emissions were noticeably higher. The findings demonstrated the possibility of using plastic pyrolysis fuel as a diesel substitute.

This review critically discussed recent developments in hydrothermal carbonization (HTC) of food waste and its valorization to solid fuel. Food waste properties and fundamentals of the HTC reactor were also covered. The review further discussed the effect of temperature, contact time, pressure, water–biomass ratio, and heating rate on the HTC of food waste on the physiochemical properties of hydrochar. Literature review of the properties of the hydrochar produced from food waste in different studies shows that it possesses elemental, proximate, and energy properties that are comparable to sub-bituminous coal and may be used directly as fuel or co-combusted with coal. This work conclusively identified the existing research gaps and provided recommendation for future investigations.

Efficiently converting methane into valuable chemicals via photocatalysis under mild condition represents a sustainable route to energy storage and value-added manufacture. Despite continued interest in this area, the achievements have been overshadowed by the absence of standardized protocols for conducting photocatalytic methane oxidation experiments as well as evaluating the corresponding performance. In this review, we present a structured solution aimed at addressing these challenges. Firstly, we introduce the norms underlying reactor design and outline various configurations in the gas-solid and gas-solid-liquid reaction systems. This discussion helps choosing the suitable reactors for methane conversion experiments. Subsequently, we offer a comprehensive step-by-step protocol applicable to diverse methane-conversion reactions. Emphasizing meticulous verification and accurate quantification of the products, this protocol highlights the significance of mitigating contamination sources and selecting appropriate detection methods. Lastly, we propose the standardized performance metrics crucial for evaluating photocatalytic methane conversion. By defining these metrics, the community could obtain the consensus of assessing the performance across different studies. Moving forward, the future of photocatalytic methane conversion necessitates further refinement of stringent experimental standards and evaluation criteria. Moreover, development of scalable reactor is essential to facilitate the transition from laboratory proof-of-concept to potentially industrial production., (© 2024 Wiley-VCH GmbH.)

In this work, a dynamic, one-dimensional, first principle-based model of a novel membrane storage reactor (MSR) process is developed and simulated. The resulting governing equations are rendered dimensionless and are shown to feature two dimensionless groups that can be used to affect process performance. The novel process is shown to intensify production of a desired species through the creation of two physically distinct domains separated by a semipermeable boundary, and dynamic operation. A number of metrics are then introduced and applied to a case study on Steam Methane Reforming, for which a parametric study is carried out which establishes the superior performance of the MSR when compared to a reactor operating at steady state (SSR). [ABSTRACT FROM AUTHOR]

The effects of anode materials, chloride ion concentration, current density and pH value on the treatment of landfill leachate are summarized, as well as the three-dimensional granular activated carbon bed electrochemical reactor and single-chamber filter press micro-loop reactor. The combination forms and application conditions of electrochemical oxidation technology with other processes are expounded. It is pointed out that developing new electrode materials, searching for effective chlorine removal methods, exploring new combination technologies of electrochemistry with other processes are the key points of future research work. [ABSTRACT FROM AUTHOR]

This study investigates the decomposition of methane using solar thermal energy as a heat source. Instead of the direct thermal decomposition of the methane at a temperature of 1200 °C or higher, a catalyst coated with carbon black on a metal foam was used to lower the temperature and activation energy required for the reaction, and to increase the yield. To supply solar heat during the reaction, a reactor suitable for a solar concentrating system was developed. In this process, a direct heating type reactor with quartz was initially applied, and a number of problems were identified. An indirect heating type reactor with an insulated cavity and a rotating part was subsequently developed, followed by a thermal barrier coating application. Methane decomposition experiments were conducted in a 40 kW solar furnace at the Korea Institute of Energy Research. Conversion rates of 96.7% and 82.6% were achieved when the methane flow rate was 20 L/min and 40 L/min, respectively. [ABSTRACT FROM AUTHOR]

Supercritical water oxidation (SCWO) is a promising technology for treating degradation-resistant organic waste. In this paper, the basic principles and technical advantages of supercritical water oxidation technology are introduced, and the research on and technical characteristics of commercial enterprises are summarized. The typical SCWO process is composed of pretreatment, pressurization, preheating, reaction, cooling, depressurization, gas-liquid-solid separation and oxidant modules. Various SCWO process schemes should be developed to accommodate site conditions, avoid corrosion, prevent salt deposition, reduce building investment and minimize operational expenses. The system could be classified in the form of heat recovery, feed pretreatment, salt separation and reactor. The application range of various process technologies was clarified, and the current research on SCWO processes was summarized. [ABSTRACT FROM AUTHOR]

The controlled corrosion of zerovalent iron (ZVI) is crucial for the favorable performance of ZVI toward metal(loid)s removal, and dissolved oxygen (DO) plays an important role in the process of ZVI corrosion. However, few efforts have been made to control the concentration of DO in real practice. In this study, we found that the electron efficiency and the specific removal capacity of ZVI toward the removal of four metal(loid)s were increased by 1.2–9.1 times and 1.2–3.6 times, respectively, by simply closing the reactor, while the removal kinetics of metal(loid)s was slightly influenced. The rate constants obtained under open condition were always greater than those obtained under closed condition, and the removal amounts of metal(loid)s by ZVI at the reaction equilibrium under closed condition were nearly equivalent to those under open condition. Compared with the case under open condition, the consumption‐redissolution process of DO was decelerated under closed condition, and the rapid corrosion of ZVI was alleviated subsequently. Although closing the reactor is simple, it does contribute much to the favorable electron efficiency of ZVI toward metal(loid)s sequestration and can be easily adopted in real practice. © 2021 Water Environment Federation Practitioner points: Closing the reactor promoted the selectivity of ZVI towards four metal(loid)s removal.The consumption‐redissolution process of DO and corrosion of ZVI were decelerated by closing the reactor.Metal(loid)s were reduced to lower valence by ZVI under closed condition.Effect of DO was different when ZVI was applied to remove different metal(loid)s. [ABSTRACT FROM AUTHOR]

O saneamento ambiental inadequado contribui para a poluição da água dos mananciais, bem como o surgimento de casos de doenças de veiculação hídrica. No entanto, a radiação solar é uma alternativa de baixo custo, fácil operação e efetiva para desinfecção de águas cinza. Objetivou-se, com o presente trabalho, identificar os agrupamentos de variáveis meteorológicas e qualitativas de amostras de águas cinza tratadas em reator solar no semiárido potiguar. Para isso, utilizou-se uma estação de tratamento de águas cinza composta por tanque séptico, filtro anaeróbio e reator solar. Os testes foram realizados de julho a dezembro de 2015, mensalmente. No reator solar foram mantidas lâminas de águas cinza de 0,1 m, que ficaram expostas à radiação solar das 8h às 16h, sendo coletadas alíquotas a cada duas horas. As amostras coletadas foram submetidas às análises de pH, oxigênio dissolvido, temperatura, condutividade elétrica, sólidos suspensos totais, turbidez, coliformes totais, E. coli e ovos de helmintos. Foram monitoradas, também, as variáveis: temperatura do ar e radiação solar global. Os dados obtidos foram submetidos à análise de agrupamento hierárquico que resultou na formação de quatro grupos, demonstrando que o agrupamento ocorreu em função da sazonalidade, e do tempo de exposição solar ao qual as amostras de águas cinza foram submetidas. A desinfecção solar configura-se como uma alternativa viável, técnica e economicamente, que permite redução significativa de patógenos, possibilitando o uso agrícola de água cinza. [ABSTRACT FROM AUTHOR]

At present, the mature low temperature denitration technologies applied in hydrogen production reformer mainly include low nitrogen combustion technology and selective catalytic reduction technology (SCR). Low temperature SCR denitration technology is more suitable for denitration transformation of petrochemical hydrogen production reformer. The key of denitration technology lies in the selection of catalyst. Through the transformation example, this paper puts forward the technical transformation of low temperature denitration with domestic manganese catalyst to stabilize the NO% concentration at the outlet of reformer below 50 mg/m³, which has the characteristics of maintaining the original process flow configuration of hydrogen pro duction reformer, stable performance, reliable technology and low investment. In the process of reconstruction design, auxiliary design such as flow field simulation and system optimization can reduce construction investment and improve operation reliability. It can provide reference for denitration transformation of hydrogen production reformer. [ABSTRACT FROM AUTHOR]

Globally, the reserves of heavy crude oil are seven times more abundant than that of light crude, and yet, they are underutilized because of their high viscosity and density, which is largely due to the presence of large amounts of asphaltenes. Biotransformation of heavy oil asphaltenes into smaller metabolites can be used for reducing their viscosity. Several microorganisms capable of asphaltene biodegradation have been reported but only few have been characterized for its biotransformation. In the present study, a 9-membered microbial consortium was isolated from an oil contaminated soil. About 72% and 75% asphaltene biotransformation was achieved by growing cells at shake flask level and in a 1.5 l bioreactor, respectively. A representative structure of asphaltene was constructed based on LC–MS, 1H-NMR, 13C-NMR, FT-IR, ICPMS and elemental analysis (CHNS) of n-heptane purified asphaltene from Maya crude oil. Biotransformation of asphaltene, as analyzed by performing 1H-NMR, FT-IR and elemental analysis, resulted in 80% decrease in S and N when compared to the control along with incorporation of oxygen in the structure of asphaltene. About 91% decrease in the viscosity of the Maya crude oil was observed after two weeks when oil: aqueous phase ratio was 1:9. The results suggest that the isolated microbial consortium can be used for biological upgradation of heavy crude oil. To our knowledge, this is the first report where a microbial consortium resulted in such high asphaltene biotransformation. [ABSTRACT FROM AUTHOR]

The present study deals with the treatment of complex waste (WW) treated for removal of chemical oxygen demand (COD) of the food industry by a sono-Fenton process using a batch reactor. The response surface methodology (RSM) was employed to investigate the five independent variables, such as reaction time, the molar ratio of H2O2/Fe2+, volume ratio of H2O2/WW, pH of waste, and ultrasonic density on COD removal. The experimental data was optimized. The optimization yields the conditions: Reaction time of 24 min, HP:Fe molar ratio of 2.8, HP:WW volume ratio of 1.9 ml/L, pH of 3.6 and an ultrasonic density of 1.8 W/L. The predicted value of COD was 91% and the experimental result was 90%. The composite desirability value (D) of the predicted percent of COD removal at the optimized level of variables was close to one (D = 0.991). [ABSTRACT FROM AUTHOR]

The digital acoustic model of a nuclear reactor (NRDAM) is represented as a self-oscillatory system belonging to a special class of nonlinear dissipative systems that can generate sustained oscillations whose parameters do not depend on the initial conditions and are only governed by the properties of the system itself. It has been found that a pressurized water reactor with coolant flowing in a turbulent mode is an open system of high complexity with a large number of components with links between them being probabilistic rather than predetermined in nature. The coolant loop components featuring negative dissipation (negative friction) are revealed. It is shown that chaotic turbulent pulsations and vortices are self-organized in these components into ordered wave oscillations, the frequency of which is determined according to the Thomson (Kelvin) formula. An electronic generator of self-oscillations with a transformer feedback used in radio engineering circuits has similar properties. A nozzle is an acoustic analog of a transformer. A negative resistance contained in nonlinear dynamic systems like a nozzle or a natural circulation loop results in that chaotic turbulent disturbances become self-organized, and self-oscillations are generated in the form of acoustic standing waves (ASW). Based on theoretical and experimental data, the certainty of the ability of a reactor together with the pipelines connected to it to simultaneously generate several ASWs—a property that has not been known previously—is confirmed. By using the NRDAM in designing and operation of nuclear power plants (NPPs), it becomes possible to reveal the sources of ASWs arising in the coolant, their occurrence conditions, and frequency. The use of the NRDAM is also necessary for determining the effect that the coolant circuit equipment geometrical parameters and layout have on the interaction of neutronic, thermal-hydraulic, and vibroacoustic processes. By applying the NRDAM, it becomes possible to optimize the engineering and design solutions in developing new-generation NPPs by eliminating the conditions causing the occurrence of undesirable self-oscillations of coolant and vibroacoustic resonances resulting from the coincidence of the ASW frequencies with the vibration frequencies of nuclear fuel and equipment in normal and emergency operation modes and also under the conditions of shock impacts and seismic loads. [ABSTRACT FROM AUTHOR]

Copyright of Experimental Technology & Management is the property of Experimental Technology & Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A nuclear power plant's safe operation involves the planning for non-standard operational emergencies, where pre-determined safety measures and damage control interventions must be taken into consideration depending on the developed event. The definition of the severe accident management cannot be explained in a single concept, it needs to be examined in detail. As a result of this it becomes necessary to specify the procedure guidelines appropriate to the nature of the event, which can be used with optimal efficiency under hierarchical organisational control. The experience of nuclear accidents in the world and the precognition of future events, the knowledge of existing guidelines for severe accident management needs to be deepened continuously, but at the same time it can be parallelly upgraded with the application of new technologies. [ABSTRACT FROM AUTHOR]

Abstract In the Daya Bay Reactor Neutrino Experiment 960 20-cm-diameter waterproof photomultiplier tubes are used to instrument three water pools as Cherenkov detectors for detecting cosmic-ray muons. Of these 960 photomultiplier tubes, 341 are recycled from the MACRO experiment. A systematic program was undertaken to refurbish them as waterproof assemblies. In the context of passing the water leakage check, a success rate better than 97% was achieved. Details of the design, fabrication, testing, operation, and performance of these waterproofed photomultiplier-tube assemblies are presented.

Abstract In the Daya Bay Reactor Neutrino Experiment 960 20-cm-diameter waterproof photomultiplier tubes are used to instrument three water pools as Cherenkov detectors for detecting cosmic-ray muons. Of these 960 photomultiplier tubes, 341 are recycled from the MACRO experiment. A systematic program was undertaken to refurbish them as waterproof assemblies. In the context of passing the water leakage check, a success rate better than 97% was achieved. Details of the design, fabrication, testing, operation, and performance of these waterproofed photomultiplier-tube assemblies are presented.

We report on the design of a modular, high-temperature thermochemical energy storage system based on endothermic-exothermic reversible gas-solid reactions for application in concentrated solar power and industrial thermal processes. It consists of an array of tubular reactors, each containing an annular packed bed subjected to radial flow, and integrated in series with a thermocline-based sensible thermal energy storage. The calcination-carbonation of limestone, CaCO3 ↔ CaO + CO2, is selected as the reversible thermochemical reaction for the experimental demonstration. Synthetized 4.2 mm-mean size agglomerates and 2 mm-mean size granules of CaO with 42 %wt sintering-inhibitor MgO support attained reaction extents of up to 84.0% for agglomerates and 31.9% for granules, and good cycling stability in pressure-swing and temperature-swing thermogravimetric runs. A lab-scale reactor prototype is fabricated and tested with both formulations for 80 consecutive carbonation-calcination cycles at ambient pressure using a temperature-swing mode between 830°C and 930°C. The reactor exhibited stable cyclic operation and low pressure drop, and yielded specific gravimetric and volumetric heat storage capacities of 866 kJ/kg and 322 MJ/m3 for agglomerates, respectively, and 450 kJ/kg and 134 MJ/m3 for granules, respectively.

Thermochemical heat storage has attracted significant attention in recent years due to potential advantages associated with very high-energy density at the material scale and its suitability for long-duration energy storage because of almost zero loss during storage. Despite the potential, thermochemical heat storage technologies are still in the early stage of development and little has been reported on thermochemical reactors. In this paper, our recent work on the charging and discharging behavior of a fixed-bed thermochemical reactor is reported. Silica gels were used as the sorbent for the experimental work. An effective model was established to numerically study the effect of different charging conditions on the discharging behavior of the reactor, which was found to have a maximum deviation of 10.08% in terms of the root mean square error compared with the experimental results. The experimentally validated modelling also showed that the discharging temperature lift increased by 5.84 times by changing the flow direction of the air in the discharging process when the charging level was at 20%. At a charging termination temperature of 51.25 °C, the maximum discharging temperature was increased by 2.35 °C by reducing the charging flow velocity from 0.64 m/s to 0.21 m/s. An increase in the charging temperature and a decrease in the air humidity increased the maximum discharging outlet temperature lift by 3.37 and 1.89 times, respectively.

Naval propulsion reactors account for the largest non-weapons use of highly enriched uranium (HEU) in the world. The largest stores of naval propulsion fuel are in the United States, the Russian Federation, and the United Kingdom. Using low-enriched uranium (LEU) for naval propulsion reactors would allow a significant reduction in non-weapons stocks of HEU and would have significant positive impacts on global nonproliferation and counterterrorism efforts. The US Navy holds the largest declared stock of HEU for propulsion purposes, and HEU-fueled reactors power all US submarines and aircraft carriers. In 1995 and again in 2014, the Navy reported to Congress on the potential for using reactors fueled with LEU instead of HEU. The Navy’s reports to Congress in both years are lacking in substantive analysis and transparency and arguably do not provide the straightforward assessment that Congress requested. The 1995 report provided Congress with a very negative assessment of the use of LEU and offered little hope that the Navy would consider LEU-fueled reactors. In 2013, Congress asked the Navy to provide an update to its 1995 report; in response, the Navy produced only a very brief analysis in 2014. Because the congressional mandate was for an update of the 1995 report, both reports need to be examined to determine the Navy’s current position on LEU use. Sadly, that position appears to have changed little over almost 20 years, despite advances in LEU use by other navies. However, the 2014 report does indicate that the Navy might be willing to support further studies of LEU use. While an optimist might see that as a change to the Navy’s adamant desire to continue to use HEU in naval reactors, a pessimist would view the Navy’s statements as a reflection of the desire to disingenuously use LEU studies to maintain the health of the service’s research and development programs. Congress should commission qualified experts to conduct an impartial review, at classified and unclassified levels, of naval LEU use. [ABSTRACT FROM PUBLISHER]

While many states are moving away from nuclear power and decommissioning their reactors for cheaper and safer alternative energy sources, recent years have seen a spark in interest for nuclear power within the Middle East under the pretext of ‘energy independence’. This trend poses a potential threat for the safety of the region considering that nuclear power plants are prone to human errors, deliberate attacks, and natural environmental convulsions which could trigger potential transboundary fallout. Given the region’s small and compacted geography along with the increasingly volatile geopolitical instability, a regional incident would likely have much direr consequences compared to other previous nuclear incidents. As a non-nuclear power state, Qatar is not currently party to any of the nuclear civil liability conventions which could guarantee some level of compensation for the victims in case of transboundary nuclear harm. In due course, Qatar will be surrounded by nuclear reactors from the north (the Iranian Bushehr plant), the east (the UAE Barakah plant) and the west (the planned Saudi plants). As exemplified by the COVID-19 pandemic, theoretical transboundary calamities can unexpectedly become a sudden reality and there is a solemn need to work proactively when dealing with such consequential hypotheticals. Therefore, this article qualitatively assesses the relevant international conventions with an aim of being policy relevant and navigate Qatari decision-makers through the vexing web of the nuclear civil liability regimes.

While many states are moving away from nuclear power and decommissioning their reactors for cheaper and safer alternative energy sources, recent years have seen a spark in interest for nuclear power within the Middle East under the pretext of ‘energy independence’. This trend poses a potential threat for the safety of the region considering that nuclear power plants are prone to human errors, deliberate attacks, and natural environmental convulsions which could trigger potential transboundary fallout. Given the region’s small and compacted geography along with the increasingly volatile geopolitical instability, a regional incident would likely have much direr consequences compared to other previous nuclear incidents. As a non-nuclear power state, Qatar is not currently party to any of the nuclear civil liability conventions which could guarantee some level of compensation for the victims in case of transboundary nuclear harm. In due course, Qatar will be surrounded by nuclear reactors from the north (the Iranian Bushehr plant), the east (the UAE Barakah plant) and the west (the planned Saudi plants). As exemplified by the COVID-19 pandemic, theoretical transboundary calamities can unexpectedly become a sudden reality and there is a solemn need to work proactively when dealing with such consequential hypotheticals. Therefore, this article qualitatively assesses the relevant international conventions with an aim of being policy relevant and navigate Qatari decision-makers through the vexing web of the nuclear civil liability regimes.

State of the art in the field of the development of catalytic reactors for dehydrogenation of liquid organic hydrogen carriers is analyzed. Rapid and complete dehydrogenation and the possibility of repeated use of the carrier can be ensured by intensifying the heat exchange and reducing the dehydrogenation temperature; these factors should be taken into account in choosing the reactor design. Examples of using reactors with fixed, suspended, and monolithic catalysts, membrane reactors, reactors operating in the reactant vaporization/condensation modes, etc., and also universal reactors for hydrogenation/dehydrogenation of liquid organic hydrogen carriers are considered. A comparative analysis of the advantages and drawbacks of various reactor systems is made. [ABSTRACT FROM AUTHOR]

With the end of Daya Bay experimental operations in December 2020, I review the history, discoveries, measurements and impact of the Daya Bay reactor neutrino experiment in China. [ABSTRACT FROM AUTHOR]

Fischer–Tropsch (FT) process is a promising method for producing liquid fuels and other valuable chemicals through CO hydrogenation. The catalyst activity and product selectivity can be strongly affected by different parameters such as support and promoters. The physicochemical and textural properties of the support affect the metal–support interaction, crystallite size, metal dispersion, mass transfer of reactants/products, mechanical strength, and thermal stability of the catalyst. Promoters can also be used as structural, textural, electronic modifier, stabilizers, and catalyst-poison-resistant, which can improve the catalytic performance. According to the parameters mentioned above, this paper reviews the brief history of the FT process, the effect of different supports and promoters on the catalytic performance of cobalt-based catalysts. In addition to the catalyst properties, the reactor must also be designed appropriately to handle the heat of this highly exothermic reaction. The reactor types have also been reviewed and compared as a crucial part of the catalytic reactions. [ABSTRACT FROM AUTHOR]

Understanding of extreme weather conditions at the site of interest is essentially required in the design of engineering structures so that the structures can withstand weather stresses. This paper presents an analysis of extreme values of meteorological elements observed at Narora site for the last three decades (1989–2019). The elements considered are extreme air temperature (°C), minimum relative humidity (%), extreme wind gust (km/h), maximum rainfall (mm) in a day and a month, and annual rainfall. The extreme value analysis reveals that the maximum air temperature, maximum wind gust at 30 m, maximum monthly rainfall, and maximum annual rainfall obey Fisher-Tippett Type-1/Gumbel extreme value distribution, whereas minimum air temperature, minimum relative humidity (%), annual daily maximum rainfall (mm), and annual minimum rainfall (mm) obey Fisher-Tippett Type-2/Frechet extreme value distribution function. Distribution function parameters, i.e., location, scale, and shape parameter for each variable, have been determined. Extreme values corresponding to return periods of 50, 100, and 1000 years are worked out using best fit linear regression curve as a compliance of the Atomic Energy Regulatory Board Safety Guide Recommendations. The derived extreme values are particularly useful to designer for arriving at suitable design basis values of different elements to ensure the safety of the reactors and other civil structures in Narora region, with respect to stresses due to weather conditions. Extreme values corresponding to return periods of 50 and 100 years at Narora are compared with corresponding values at other three nuclear reactor sites in India, namely, Tarapur, Kalpakkam, and Trombay. In addition, the time series pattern analysis of rainfall for 31 years at the Narora site closely following the 2-year moving average rainfall data pattern. These results can be used for water harvesting, irrigation, and floods management plans in the future. [ABSTRACT FROM AUTHOR]

After going through several files containing new documents about the civilian nuclear programs in Romania and Poland, we can say that the main link between them was made through the Soviet authorities -- who launched those programs in the two countries in 1955 because the level at which were the researches in the USSR it already allowed to manufacture atomic and thermonuclear bombs. The details of the Moscow authorities' view of using scientists from Romania, Poland and other communist countries for scientific purposes in a much broader nuclear (military and civilian) development program remain to be sought. [ABSTRACT FROM AUTHOR]

Copyright of Investigación e Innovación en Ingenierías is the property of Universidad Simon Bolivar and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this research, the degradation performance of toluene has been evaluated by the design and construction of a fixedbed photocatalytic reactor. The role of effective operational parameters was investigated, and obtained results indicated that the designed system could degrade toluene up to %95.30 at optimal conditions. The simulation of the reactor was carried out using a three-dimensional CFD to the prediction of the hydrodynamic behavior and determination of the toluene concentration along the reactor. Findings showed that the proposed model could predict the degradation rate of toluene along the reactor. The comparison of the designed system performance with other systems revealed that the current system not only could degrade toluene with higher concentration at a shorter time but also requires less photocatalyst mass per unit area, which is very important economically. The results of this study can be used in the design of photocatalytic reactors for action on an industrial scale. [ABSTRACT FROM AUTHOR]

CeO 2 and ZnO with finely rod shape were used as carriers to support copper. High-resolution transmission electron microscopy demonstrated that copper species were existed mostly in bilayer clusters containing underlying Cu+ and upper Cu0 on CeO 2 , but in big particles of 5–10 nm consisting of only Cu0 on ZnO. The amounts of underlying Cu+ in bilayers and oxygen vacancies (O v) at copper-ceria interface reached maximum when copper loading was about 10 wt%. In CO preferential oxidation reaction, the 10-Cu/CeO 2 catalyst showed the highest activity suggesting that CO adsorbed on Cu+ in bilayer clusters reacted rapidly with O 2 absorbed on adjacent O v. The near synergistic effect not only reduced the CO reaction temperature but also enhanced the CO conversion. The Cu/ZnO catalyst had weak CO adsorption and long distance of Cu0 and O v , thus it showed much low activity. By filling the 10-Cu/CeO 2 catalysts in a two-stage reactor, 1 % CO in the methanol steam reforming gas could be removed to 2 ppm after two successive CO oxidation processes, which provided a new solution for H 2 purification. • Copper dispersion on rod-shaped ceria and zinc oxide was examined with respect to copper loading. • Bilayer clusters containing Cu+ and Cu0 were dominate at CeO 2 whileparticles consisting of only Cu0 were dominate at ZnO. • The copper-ceria interface was constructed by the underlying Cu+ in bilayer clusters with the superficial O v on ceria. • The oxidation of CO was closely related to the amount and distance of Cu+ and oxygen vacancies. • 1 % CO in methanol steam reforming gas can be removed down to 2 ppm by providing oxygen twice. [ABSTRACT FROM AUTHOR]

• Hydro-deoxynation of pyrolytic oil has been reviewed. • Bio-oil stability parameters are studied and discussed in-depth. • Techn-economic analysis (TEA) of Hydro-deoxynation of pyrolytic oil is reviewed. • The influence of reactors types on HDO of pyroltic oil is also discussed. • HDO of pyrolysis oil is a feasible technology from the economic point of view. The rapid depletion of fossil fuels and environmental concerns have led researchers to explore alternative sources of energy. Pyrolytic oil derived from biomass is considered to be a potential alternative to fossil fuels, but it lacks certain physicochemical properties that make it unsuitable to be used as fuel. For instance, the high oxygen content in the pyrolytic oil exhibits chemical instability, the tendency to polymerize, and low energy density compared to traditional fuels. The hydrodeoxygenation (HDO) method is a viable technique to enhance the desirable characteristics of pyrolytic oil for commercial applications. This method has the disadvantage of catalyst deactivation owed due to coking, and its extent depends on the nature of oxy-compounds, catalyst type, and experimental conditions. However, by varying the experimental parameters such as catalyst acidity, temperature, pressure, solvent, and reaction time, the HDO product characteristics may be tailored to meet the specific requirements and applications. In this work, we have presented a comprehensive review of multiple alternatives to produce pyrolytic oil with essential fuel characteristics. The techno-economic analysis (TEA) and kinetic analysis of the pyrolytic oil were also elaborated. Overall, the review paper highlights the influence of process variables, kinetics investigation, reactor types and techno-economic analysis of HDO. [ABSTRACT FROM AUTHOR]

Among a series of important safety parameters necessary for a complete analysis of a nuclear reactor core, the nuclear safety operating margin of a nuclear reactor is of great importance. The methodology generally used is to combine thermalhydraulic calculations with neutronic calculations. In this work, new Power Peaking Factors (PPFs) are calculated for the NUR nuclear research reactor core X-1 configuration by two ways; a deterministic way using WIMSD-CITVAP neutronic calculation in a fine calculation model, and a second way by a probabilistic method using MCNP5 model. The obtained results give the PPFs for each nuclear reactor core channel and the hot channel is then determined. Once this channel known, an asymptotic thermalhydraulic model is applied. This model gives the coolant and the cladding temperature evolutions in the hot channel for the calculated PPFs in the two presented models. All these results are compared with those obtained using the old PPF commonly used in such calculations. Results show that PPFs obtained by deterministic method are the most conservative. Thus, this last result is retained for a nuclear safety evaluation. An equation set-up is made for calculating the critical heat flux ratio. This ratio is verified to be greater than the limit of nuclear safety operating margin for NUR nuclear reactor. [ABSTRACT FROM AUTHOR]