Simulation of Polygeneration Systems

Directory of Open Access Journals (Sweden)

Francesco Calise

2016-11-01

Full Text Available This Special Issue aims at collecting the recent studies dealing with polygeneration systems, with a special focus on the possible integration of different technologies into a single system, able to convert one or multiple energy sources into energy services (electricity, heat and cooling and other useful products (e.g., desalinized water, hydrogen, glycerin, ammonia, etc.. Renewable sources (solar, wind, hydro, biomass and geothermal, as well as fossil fuels, feeding advanced energy systems such as fuel cells and cogeneration systems, are considered. Special attention is paid to control strategies and to the management of the systems in general. Studies including thermoeconomic analyses and system optimizations are presented.

Application of House of Quality in evaluation of low rank coal pyrolysis polygeneration technologies

International Nuclear Information System (INIS)

Yang, Qingchun; Yang, Siyu; Qian, Yu; Kraslawski, Andrzej

2015-01-01

Highlights: • House of Quality method was used for assessment of coal pyrolysis polygeneration technologies. • Low rank coal pyrolysis polygeneration processes based on solid heat carrier, moving bed and fluidized bed were evaluated. • Technical and environmental criteria for the assessment of technologies were used. • Low rank coal pyrolysis polygeneration process based on a fluidized bed is the best option. - Abstract: Increasing interest in low rank coal pyrolysis (LRCP) polygeneration has resulted in the development of a number of different technologies and approaches. Evaluation of LRCP processes should include not only conventional efficiency, economic and environmental assessments, but also take into consideration sustainability aspects. As a result of the many complex variables involved, selection of the most suitable LRCP technology becomes a challenging task. This paper applies a House of Quality method in comprehensive evaluation of LRCP. A multi-level evaluation model addressing 19 customer needs and analyzing 10 technical characteristics is developed. Using the evaluation model, the paper evaluates three LRCP technologies, which are based on solid heat carrier, moving bed and fluidized bed concepts, respectively. The results show that the three most important customer needs are level of technical maturity, wastewater emissions, and internal rate of return. The three most important technical characteristics are production costs, investment costs and waste emissions. On the basis of the conducted analysis, it is concluded that the LRCP process utilizing a fluidized bed approach is the optimal alternative studied

On battery-less autonomous polygeneration microgrids: Investigation of the combined hybrid capacitors/hydrogen alternative

International Nuclear Information System (INIS)

Kyriakarakos, George; Piromalis, Dimitrios D.; Arvanitis, Konstantinos G.; Dounis, Anastasios I.; Papadakis, George

2015-01-01

Highlights: • A battery-less autonomous polygeneration microgrid is technically feasible. • Laboratory testing of hybrid capacitors. • Investigation of hybrid capacitors utilization along with hydrogen subsystem. - Abstract: The autonomous polygeneration microgrid topology aims to cover holistically the needs in remote areas as far as electrical power, potable water through desalination, fuel for transportation in the form of hydrogen, heating and cooling are concerned. Deep discharge lead acid batteries are mostly used in such systems, associated with specific disadvantages, both technical and environmental. This paper investigated the possibility of replacing the battery bank from a polygeneration microgrid with a hybrid capacitor bank and more intensive utilization of a hydrogen subsystem. Initially commercial hybrid capacitors were tested under laboratory conditions and based on the respective results a case study was performed. The optimized combination of hybrid capacitors and higher hydrogen usage was then investigated through simulations and compared to a polygeneration microgrid featuring deep discharge lead acid batteries. From the results it was clear that it is technically possible to exchange the battery bank with a hybrid capacitor bank and higher hydrogen utilization. From the economic point of view, the current cost of the hybrid capacitors and the hydrogen components is high which leads to higher overall cost in comparison with deep discharge lead acid batteries. Taking into account, though, the decreasing cost prospects and trends of both the hybrid capacitors and the hydrogen components it is expected that this approach will become economically competitive in a few years

Biomass polygeneration - technology state-of-the-art, systems and policy instruments; Bioenergikombinat - tekniktrender, system och styrmedel

Energy Technology Data Exchange (ETDEWEB)

Gode, Jenny; Hagberg, Linus; Holmgren, Kristina; Stripple, Haakan

2007-09-15

The development status of biofuel technologies and pellets has been reviewed, with focus on the possibilities for polygeneration with combined heat and power (CHP). Policy instruments important for the development of polygeneration plants have been analysed and interviews with potential stakeholders have been carried out. Fermentation of biomass for ethanol production, gasification and conversion to synthesis gas, biodiesel production from vegetable and animal oils, as well as anaerobic digestion for biogas production are examples of common biofuel technologies. Some of these are commercially available whereas others require further development. Substantial research and development is also spent to develop new technologies for biofuel production. Biofuel production can often benefit from integration with CHP resulting in increased efficiency and energy balances. The potentials for integration vary between different biofuels, but the most common options are integration with respect to the raw material, heat demand, waste heat and waste products. The integration potential for pellets is mainly associated with the raw material and the heat demand for drying of the raw material. Integration of biofuel and/or pellets production with CHP might increase the potential for power production since a new heat customer is provided the whole year around. The heat demand for some biofuels and for pellets can be covered by district heating, whereas some biofuels require steam. Policy instruments can strongly influence the development of biofuels and thereby has a potential to affect the incentives for investments in polygeneration. From a climate point of view, it can be argued that biomass is better used for emission reductions in other sectors where higher reduction of greenhouse gases can be achieved to a lower cost. However, there are other driving forces that motivate increased use of biofuels, such as security of supply, need of revised agriculture policy and reduction of

Thermodynamic analysis of a coal-based polygeneration system with partial gasification

International Nuclear Information System (INIS)

Li, Yuanyuan; Zhang, Guoqiang; Yang, Yongping; Zhai, Dailong; Zhang, Kai; Xu, Gang

2014-01-01

This study proposed a polygeneration system based on coal partial gasification, in which methanol and power were generated. This proposed system, comprising chemical and power islands, was designed and its characteristics are analyzed. The commercial software Aspen Plus was used to perform the system analysis. In the case study, the energy and exergy efficiency values of the proposed polygeneration system were 51.16% and 50.58%, which are 2.34% and 2.10%, respectively, higher than that of the reference system. Energy-Utilization Diagram analysis showed that removing composition adjustment and recycling 72.7% of the unreacted gas could reduce the exergy destruction during methanol synthesis by 46.85% and that the char utilized to preheat the compressed air could reduce the exergy destruction during combustion by 10.28%. Sensitivity analysis was also performed. At the same capacity ratio, the energy and exergy efficiency values of the proposed system were 1.30%–2.48% and 1.21%–2.30% higher than that of the reference system, respectively. The range of chemical-to-power capacity ratio in the proposed system was 0.41–1.40, which was narrower than that in the reference system. But the range of 1.04–1.4 was not recommended for the disappearance of energy saving potential in methanol synthesis. - Highlights: • A novel polygeneration system based on coal partial gasification is proposed. • The efficient conversion method for methanol and power is explored. • The exergy destruction in chemical energy conversion processes is decreased. • Thermodynamic performance and system characteristics are analyzed

Thermo-economic optimization of the impact of renewable generators on poly-generation smart-grids including hot thermal storage

International Nuclear Information System (INIS)

Rivarolo, M.; Greco, A.; Massardo, A.F.

2013-01-01

Highlights: ► We model a poly-generation grid including thermal storage and renewable generators. ► We analyze the impact of random renewable generators on the grid performance. ► We carry out the grid optimization using a time-dependent thermo-economic approach. ► We present the importance of the storage system to optimize the RES impact. - Abstract: In this paper, the impact of not controllable renewable energy generators (wind turbines and solar photovoltaic panels) on the thermo-economic optimum performance of poly-generation smart grids is investigated using an original time dependent hierarchical approach. The grid used for the analysis is the one installed at the University of Genoa for research activities. It is based on different prime movers: (i) 100 kWe micro gas turbine, (ii) 20 kWe internal combustion engine powered by gases to produce both electrical and thermal (hot water) energy and (iii) a 100 kWth adsorption chiller to produce cooling (cold water) energy. The grid includes thermal storage tanks to manage the thermal demand load during the year. The plant under analysis is also equipped with two renewable non-controllable generators: a small size wind turbine and photovoltaic solar panels. The size and the management of the system studied in this work have been optimized, in order to minimize both capital and variable costs. A time-dependent thermo-economic hierarchical approach developed by the authors has been used, considering the time-dependent electrical, thermal and cooling load demands during the year as problem constraints. The results are presented and discussed in depth and show the strong interaction between fossil and renewable resources, and the importance of an appropriate storage system to optimize the RES impact taking into account the multiproduct character of the grid under investigation.

Torrefaction of agriculture straws and its application on biomass pyrolysis poly-generation.

Science.gov (United States)

Chen, Yingquan; Yang, Haiping; Yang, Qing; Hao, Hongmeng; Zhu, Bo; Chen, Hanping

2014-03-01

This study investigated the properties of corn stalk and cotton stalk after torrefaction, and the effects of torrefaction on product properties obtained under the optimal condition of biomass pyrolysis polygeneration. The color of the torrefied biomass chars darkened, and the grindability was upgraded, with finer particles formed and grinding energy consumption reduced. The moisture and oxygen content significantly decreased whereas the carbon content increased considerably. It was found that torrefaction had different effects on the char, liquid oil and biogas from biomass pyrolysis polygeneration. Compared to raw straws, the output of chars from pyrolysis of torrefied straws increased and the quality of chars as a solid fuel had no significant change, while the output of liquid oil and biogas decreased. The liquid oil contained more concentrated phenols with less water content below 40wt.%, and the biogas contained more concentrated H2 and CH4 with higher LHV up to 15MJ/nm(3). Copyright © 2014 Elsevier Ltd. All rights reserved.

Polygeneration system based on PEMFC, CPVT and electrolyzer: Dynamic simulation and energetic and economic analysis

International Nuclear Information System (INIS)

Calise, Francesco; Figaj, Rafal Damian; Massarotti, Nicola; Mauro, Alessandro; Vanoli, Laura

2017-01-01

Highlights: • A novel polygeneration system is presented. • System includes CPVT collectors, PEM fuel cell, absorption chiller and electrolyzer. • The system provides heating/cooling, domestic hot water, electricity, hydrogen and oxygen. • The system simple payback period is 12.5 years, 5.8 years in case of incentive. • The optimal fuel cell nominal power results 100 kW. - Abstract: This paper presents a dynamic simulation model and an energetic and economic analysis of novel polygeneration system. The system integrates: cogenerative Proton Exchange Membrane Fuel Cell (PEMFC), Concentrated PhotoVoltaic-Thermal (CPVT) collectors, alkaline electrolyzer and single-stage LiBr/H_2O absorption chiller. The plant is designed to supply electrical energy, space heating or cooling and domestic hot water for a small university building. The system produces hydrogen and oxygen, the first one is stored and then it is supplied to the fuel cell, while the second one is sold. The electrolyzer system is powered only by the CPVT collectors, only a small amount of the solar electrical energy is available to the user. Such electric energy along with the one produced by the PEM fuel cell are used by the user and/or supplied to the grid. The system is designed and dynamically simulated using TRNSYS software package. This study is based on a model previously developed by the authors. In particular, the system was modified in order to implement the new components (CPVT, alkaline electrolyzer, hydrogen and oxygen system) in this work. Special attention is paid to the control strategy of the proposed system in order to achieve the optimal system configuration. Daily, weekly and yearly results carried out with the dynamic simulation are presented. Finally, a sensitivity analysis was performed in order to determine the system performance as a function of the main design parameters. The energetic and economic analysis shows that the system can ensure significant energy savings and it

A multi-agent decentralized energy management system based on distributed intelligence for the design and control of autonomous polygeneration microgrids

International Nuclear Information System (INIS)

Karavas, Christos-Spyridon; Kyriakarakos, George; Arvanitis, Konstantinos G.; Papadakis, George

2015-01-01

Highlights: • A decentralized energy management system based on multi agent systems theory. • A decentralized energy management system is technically feasible. • A decentralized approach utilizes the devices better than a centralized one. • A decentralized energy management system is economically competitive. - Abstract: The autonomous polygeneration microgrid topology has been developed in order to cover holistically needs in a remote area such as electrical energy, space heating and cooling, potable water through desalination and hydrogen as fuel for transportation. The existence of an advanced energy management system is essential for the operation of an autonomous polygeneration microgrid. So far, energy management systems based on a centralized management and control have been developed for the autonomous polygeneration microgrid topology based on computational intelligence approaches. A decentralized management and control energy management system can have important benefits, when taking into consideration the autonomous character of these microgrids. This paper presents the design and investigation of a decentralized energy management system for the autonomous polygeneration microgrid topology. The decentralized energy management system gives the possibility to control each unit of the microgrid independently. The most important advantage of using a decentralized architecture is that the managed microgrid has much higher chances of partial operation in cases when malfunctions occur at different parts of it, instead of a complete system breakdown. The designed system was based on a multi-agent system and employed Fuzzy Cognitive Maps for its implementation. It was then compared through a case study with an existing centralized energy management system. The technical performance of the decentralized solution performance is on par with the existing centralized one, presenting improvements in financial and operational terms for the implementation and

A polygeneration from a dual-gas partial catalytic oxidation coupling with an oxygen-permeable membrane reactor

International Nuclear Information System (INIS)

Hao, Yanhong; Huang, Yi; Gong, Minhui; Li, Wenying; Feng, Jie; Yi, Qun

2015-01-01

Highlights: • A new polygeneration system (PL-PCO-OPMR) to DME/methanol/power is proposed. • Exergeo-economic analysis is adopted to disclose the performance of systems. • Key technological conditions and parameters for PL-PCO-OPMR are optimized. • PL-PCO-OPMR shows high energy efficiency and low CO_2 emission. • PL-PCO-OPMR is an attractive way for high efficient and clean use of COG and CGG. - Abstract: Polygeneration system, typically involving chemicals/fuels and electricity co-production, is a promising technology for the sustainable development of energy and environment. In this study, a new polygeneration system based on coal and coke oven gas (COG) inputs for co-production of dimethyl ether (DME)/methanol and electricity is proposed. In the new system, an appropriate syngas for the synthesis of DME is from coal gasified gas (CGG) reforming of COG coupled with an oxygen-permeable membrane reactor, in which both COG and CGG reforming process and fuel combustion process are incorporated, which reduces exergy destruction in the whole reforming process. In order to obtain the best performance of CO_2 reduction, energy saving and economic benefit, the key operation parameters of the proposed process are analyzed and optimized. The new system is compared with the process based on CH_4/CO_2 dry reforming, in terms of exergy efficiency, exergy cost and CO_2 emissions. Through the new system, the exergy efficiency can be increased by 7.8%, the exergy cost can be reduced by 0.88 USD/GJ and the CO_2 emission can be reduced by 0.023 kg/MJ. These results suggest that the polygeneration system from CGG and COG partial catalytic oxidation coupling with an oxygen-permeable membrane reactor (PL-PCO-OPMR) would be a more attractive way for highly efficient and clean use of CGG and COG.

Design and dynamic simulation of a novel polygeneration system fed by vegetable oil and by solar energy

International Nuclear Information System (INIS)

Calise, Francesco; Palombo, Adolfo; Vanoli, Laura

2012-01-01

Highlights: ► A novel polygeneration system based on engines (RE) fed by rapeseed oil is investigated. ► RE are integrated with high temperature solar heating and cooling systems. ► The polygeneration system is dynamically investigated for a Mediterranean Climate. ► System performance is excellent from the energetic point of view. ► The system is economically profitable only in case of feed-in tariffs. - Abstract: In this paper the integration of vegetable oil-fed reciprocating engines with solar thermal collector is investigated, seeking to design a novel polygeneration system producing: electricity, space heating and cooling and domestic hot water, for a university building located in Naples (Italy), assumed as case study. The polygeneration system is based on the following main components: concentrating parabolic trough solar collector, double-stage LiBr–H 2 O absorption chiller and a reciprocating engine fed by vegetable oil. The engine operates at full load producing electrical energy which is in part consumed by the building lights and equipments, in part used by the system passive loads and the rest is eventually sold to the grid. In fact, the engine is grid connected in order to perform a convenient net metering. The system was designed and then simulated by means of a zero-dimensional transient simulation model, developed using the TRNSYS software. The simulation tool developed by the authors allows one to analyze the results for different time basis (minutes, days, weeks, months and years), from both energetic and economic points of view. The economic results show that the system under investigation is profitable, especially if properly funded.

Oil palm biomass utilization as an energy source and its possibility use for polygeneration scenarios in Langsa City, Aceh Province, Indonesia

Science.gov (United States)

Hani, M. R.; Mahidin, M.; Husin, H.; Hamdani, H.; Khairil, K.

2018-03-01

This article deals with the discussion on the recent status of oil palm biomass utilization as an energy source and its possibility use for polygeneration system. The discussion focused only on the energy viewpoint. At this point, many projects and research have been developed in order to utilize the oil palm biomass to meet the energy demand of industries and communities, especially in the largest producing countries: Indonesia and Malaysia; and a few in Thailand, Africa, Latin America and Europe. Through the simulation work in the case study, it is evident that the government of Langsa City can fulfill the fresh water to their community and electricity to Langsa Harbor only by using EFB and PKS from one POM with the generated power of 12 MW, while the desalination plant consumes about 7 MW of electricity. If all potency of biomass from all POMs in Aceh Timur and Aceh Tamiang, without the combination of other primary energy sources is used, Langsa City might earn surplus of energy. The use of the oil palm biomass for polygeneration scenarios is possible and feasible from the technical point of view.

Performance of simulated flexible integrated gasification polygeneration facilities. Part A: A technical-energetic assessment

NARCIS (Netherlands)

Meerman, J.C.; Ramírez Ramírez, C.A.; Turkenburg, W.C.; Faaij, A.P.C.

2011-01-01

This article investigates technical possibilities and performances of flexible integrated gasification polygeneration (IG-PG) facilities equipped with CO2 capture for the near future. These facilities can produce electricity during peak hours, while switching to the production of chemicals during

Exergy analysis of a combined heat and power plant with integrated lignocellulosic ethanol production

DEFF Research Database (Denmark)

Lythcke-Jørgensen, Christoffer Ernst; Haglind, Fredrik; Clausen, Lasse Røngaard

2014-01-01

production. An exergy analysis is carried out for a modelled polygeneration system in which lignocellulosic ethanol production based on hydrothermal pretreatment is integrated in an existing combined heat and power (CHP) plant. The ethanol facility is driven by steam extracted from the CHP unit when feasible...... district heating production in the ethanol facility. The results suggest that the efficiency of integrating lignocellulosic ethanol production in CHP plants is highly dependent on operation, and it is therefore suggested that the expected operation pattern of such polygeneration system is taken......Lignocellulosic ethanol production is often assumed integrated in polygeneration systems because of its energy intensive nature. The objective of this study is to investigate potential irreversibilities from such integration, and what impact it has on the efficiency of the integrated ethanol...

Proposal and analysis of a polygeneration system for power and methanol based on natural gas and biomass as co-feed

Energy Technology Data Exchange (ETDEWEB)

Li, H.Q.; Hong, H.; Jin, H.G.; Cai, R.X. [Chinese Academy of Sciences, Beijing (China). Inst. of Engineering Thermophysics

2008-07-01

Biomass is getting increasing attention as a potential source of renewable energy as a result of global issues such as sustainable energy and reduction of greenhouse gases. Biomass is an abundant feedstock containing mainly carbon, oxygen, hydrogen, and volatile matter. The purpose of this paper was to propose a new biomass-natural gas based polygeneration system, with partial recycling unreacted syngas and without the shift process for methanol production and power generation. The paper identified the features of the proposed system and that determine the exergy ratio of chemical production and thermodynamic performance of the system. The paper provided an introduction to individual systems such as the natural gas to methanol system and biomass to methanol system. The paper also presented the suggested polygeneration system based on biomass and natural gas as co-feed. Processes that were described included syngas preparation; distillation process; and power generation. System evaluation criteria and performance were identified. It was concluded that bio-energy made the best utilization and overcame the disadvantages of the polygeneration system, partly taking the place of natural gas which is non-renewable. Bio-energy could reduce carbon dioxide emission for it is carbon neutrality. 18 refs., 3 tabs., 9 figs.

Multi-objective exergy-based optimization of a polygeneration energy system using an evolutionary algorithm

International Nuclear Information System (INIS)

Ahmadi, Pouria; Rosen, Marc A.; Dincer, Ibrahim

2012-01-01

A comprehensive thermodynamic modeling and optimization is reported of a polygeneration energy system for the simultaneous production of heating, cooling, electricity and hot water from a common energy source. This polygeneration system is composed of four major parts: gas turbine (GT) cycle, Rankine cycle, absorption cooling cycle and domestic hot water heater. A multi-objective optimization method based on an evolutionary algorithm is applied to determine the best design parameters for the system. The two objective functions utilized in the analysis are the total cost rate of the system, which is the cost associated with fuel, component purchasing and environmental impact, and the system exergy efficiency. The total cost rate of the system is minimized while the cycle exergy efficiency is maximized by using an evolutionary algorithm. To provide a deeper insight, the Pareto frontier is shown for multi-objective optimization. In addition, a closed form equation for the relationship between exergy efficiency and total cost rate is derived. Finally, a sensitivity analysis is performed to assess the effects of several design parameters on the system total exergy destruction rate, CO 2 emission and exergy efficiency.

A Game Theory Approach to Multi-Agent Decentralized Energy Management of Autonomous Polygeneration Microgrids

Directory of Open Access Journals (Sweden)

Christos-Spyridon Karavas

2017-11-01

Full Text Available Energy management systems are essential and indispensable for the secure and optimal operation of autonomous polygeneration microgrids which include distributed energy technologies and multiple electrical loads. In this paper, a multi-agent decentralized energy management system was designed. In particular, the devices of the microgrid under study were controlled as interactive agents. The energy management problem was formulated here through the application of game theory, in order to model the set of strategies between two players/agents, as a non-cooperative power control game or a cooperative one, according to the level of the energy produced by the renewable energy sources and the energy stored in the battery bank, for the purpose of accomplishing optimal energy management and control of the microgrid operation. The Nash equilibrium was used to compromise the possible diverging goals of the agents by maximizing their preferences. The proposed energy management system was then compared with a multi-agent decentralized energy management system where all the agents were assumed to be cooperative and employed agent coordination through Fuzzy Cognitive Maps. The results obtained from this comparison, demonstrate that the application of game theory based control, in autonomous polygeneration microgrids, can ensure operational and financial benefits over known energy management approaches incorporating distributed intelligence.

An appealing photo-powered multi-functional energy system for the poly-generation of hydrogen and electricity

Science.gov (United States)

Tang, Tiantian; Li, Kan; Shen, Zhemin; Sun, Tonghua; Wang, Yalin; Jia, Jinping

2015-10-01

This paper focuses on a photo-powered poly-generation system (PPS) that is powered by the photocatalytic oxidation of organic substrate to produce hydrogen energy and electrical energy synchronously. This particular device runs entirely on light energy and chemical energy of substrate without external voltage. The performance measurements and optimization experiments are all investigated by using the low concentration of pure ethanol (EtOH) solution. Compared with the conventional submerged reactor for the photogeneration of hydrogen, the hydrogen and the electric current obtained in the constructed PPS are all relatively stable in experimental period and the numerical values detected are many times higher than that of the former by using various simulated ethanol waste liquid. When using Chinese rice wine as substrate at the same ethanol content level (i.e., 0.1 mol L-1), the production of hydrogen is close to that of the pure ethanol solution in the constructed PPS, but no hydrogen is detected in the conventional submerged reactor. These results demonstrate that the constructed PPS could effectively utilize light energy and perform good capability in poly-generation of hydrogen and electricity.

Dynamic model with experimental validation of a biogas-fed SOFC plant

International Nuclear Information System (INIS)

D'Andrea, G.; Gandiglio, M.; Lanzini, A.; Santarelli, M.

2017-01-01

Highlights: • 60% of DIR into the SOFC anode reduces the air blower parasitic losses by 14%. • PID-controlled cathode airflow enables fast thermal regulation of the SOFC. • Stack overheating occurs due to unexpected reductions in the cathode airflow. • Current ramp rates higher than +0.30 A/min lead to an excessive stack overheating. - Abstract: The dynamic model of a poly-generation system based on a biogas-fed solid oxide fuel cell (SOFC) plant is presented in this paper. The poly-generation plant was developed in the framework of the FP7 EU-funded project SOFCOM ( (www.sofcom.eu)), which consists of a fuel-cell based polygeneration plant with CO_2 capture and re-use. CO_2 is recovered from the anode exhaust of the SOFC (after oxy-combustion, cooling and water condensation) and the Carbon is fixed in the form of micro-algae in a tubular photobioreactor. This work focuses on the dynamic operation of the SOFC module running on steam-reformed biogas. Both steady state and dynamic operation of the fuel cell stack and the related Balance-of-Plant (BoP) has been modeled in order to simulate the thermal behavior and performance of the system. The model was validated against experimental data gathered during the operation of the SOFCOM proof-of-concept showing good agreement with the experimental data. The validated model has been used to investigate further on the harsh off-design operation of the proof-of-concept. Simulation results provide guidelines for an improved design of the control system of the plant, highlighting the feasible operating region under safe conditions and means to maximize the overall system efficiency.

Poly-generation planning: useful lessons from models and decision support tools

DEFF Research Database (Denmark)

Rong, Aiying; Lahdelma, Risto; Grunow, Martin

2009-01-01

Increasing environmental concerns and the trends towards deregulation of energy markets have become an integral part of energy policy planning. Consequently, the requirement for environmentally sound energy production technologies has gained much ground in the energy business. The development...... of energy-efficient production technologies has experienced cogeneration and tri-generation and now is moving towards poly-generation. All these aspects have added new dimension in energy planning. The liberalized energy market requires techniques for planning under uncertainty. The growing environmental...... awareness calls for explicit handling of the impacts of energy generation on environment. Advanced production technologies require more sophisticated models for planning. The energy sector is one of the core application areas for operations research, decision sciences and intelligent techniques...

Poly-generation planning: useful lessons from models and decision support tools

DEFF Research Database (Denmark)

Rong, Aiying; Lahdelma, Risto; Grunow, Martin

2009-01-01

of energy-efficient production technologies has experienced cogeneration and tri-generation and now is moving towards poly-generation. All these aspects have added new dimension in energy planning. The liberalized energy market requires techniques for planning under uncertainty. The growing environmental...... awareness calls for explicit handling of the impacts of energy generation on environment. Advanced production technologies require more sophisticated models for planning. The energy sector is one of the core application areas for operations research, decision sciences and intelligent techniques......Increasing environmental concerns and the trends towards deregulation of energy markets have become an integral part of energy policy planning. Consequently, the requirement for environmentally sound energy production technologies has gained much ground in the energy business. The development...

Performance assessment of cogeneration and trigeneration systems for small scale applications

International Nuclear Information System (INIS)

Angrisani, Giovanni; Akisawa, Atsushi; Marrasso, Elisa; Roselli, Carlo; Sasso, Maurizio

2016-01-01

Highlights: • Indices and methods to assess the performance of polygeneration systems. • Index to evaluate the economic feasibility of trigeneration system is introduced. • Thermo-economic analysis is performed considering three commercial cogenerators. • Sensitivity analysis varying reference electric efficiency for European Countries. • Sensitivity analysis varying environmental and economic parameters. - Abstract: Cogeneration and trigeneration systems can contribute to the reduction of primary energy consumption and greenhouse gas emissions in residential and tertiary sectors, by reducing fossil fuels demand and grid losses with respect to conventional systems. To evaluate the performance of these systems, several indices and assessment methodologies can be used, due to the high complexity of such systems, which can consist of several energy conversion devices and can perform bidirectional interactions with external electric and thermal grids. In this paper, a review of the available indices and methodologies to assess the performances of polygeneration systems is provided. An index (TSS_t_r_i) aimed to assess the economic feasibility of a trigeneration system is also introduced and discussed. This activity started in the framework of the International Energy Agency Annex 54 project (“Integration of Micro-Generation and Related Energy Technologies in Buildings”), where research groups shared their expertise about methods applied in each Country to evaluate the performance of polygeneration systems. It was concluded that a thermo-economic analysis comparing the performance of a polygeneration system with those of a reference benchmark scenario, is a very suitable assessment method. Some of the reviewed methodologies are then applied to small scale commercial cogenerators. The sensitivity analysis is performed considering different reference average values of electric efficiency, unitary natural gas and electricity prices, and emission factors for

Introduction of an energy efficiency tool for small scale biomass gasifiers – A thermodynamic approach

International Nuclear Information System (INIS)

Vakalis, S.; Patuzzi, F.; Baratieri, M.

2017-01-01

Highlights: • Analysis of plants for electricity, heat and materials production. • Thermodynamic analysis by using exergy, entransy and statistical entropy. • Extrapolation of a single efficiency index by combining the thermodynamic parameters. • Application of methodology for two monitored small scale gasifiers. - Abstract: Modern gasification plants, should be treated as poly-generation facilities because, alongside the production of electricity and heat, valuable or waste materials streams are generated. Thus, integrated methods should be introduced in order to account for the full range and the nature of the products. Application of conventional hybrid indicators that convert the output into monetary units or CO_2 equivalents are a source of bias because of the inconsistency of the conversion factors and unreliability of the available data. Therefore, this study introduces a novel thermodynamic-based method for assessing gasification plants performance by means of exergy, entransy and statistical entropy. A monitoring campaign has been implemented on two small scale gasifiers and the results have been applied on the proposed method. The energy plants are compared in respect to their individual thermodynamic parameters for energy production and materials distribution. In addition, the method returns one single value which is a resultant of all the investigated parameters and is a characteristic value of the overall performance of an energy plant.

A novel polygeneration process to co-produce ethylene and electricity from shale gas with zero CO2 emissions via methane oxidative coupling

International Nuclear Information System (INIS)

Khojasteh Salkuyeh, Yaser; Adams, Thomas A.

2015-01-01

Highlights: • Development of an ethylene plant from shale gases with zero CO 2 emissions. • Oxidative coupling of methane is used for the conversion of gas to ethylene. • Polygeneration strategy is used to improve the profitability of plant. - Abstract: A techno-economic analysis of a novel process to co-produce ethylene and electricity using a recently developed methane oxidative coupling catalyst is presented. Several design variants are considered, featuring the use of traditional gas turbines, chemical looping combustion, and 100% carbon dioxide capture. Mass and energy balance simulations were carried out using Aspen Plus simulations, and particle swarm optimization was used to determine the optimal process design under a variety of market scenarios. A custom model for the gas turbine section was used to ensure that the negative impacts of various cooling strategies were factored into the analysis. The results show that by synergistically co-producing power and ethylene using this catalyst, ethylene can be produced at costs close to traditional steam cracking methods with nearly zero carbon dioxide emissions, even when factoring in the relatively poor conversion and selectivity of the chosen catalyst

How polygeneration schemes may develop under an advanced clean fossil fuel strategy under a joint sino-European initiative

International Nuclear Information System (INIS)

Hetland, Jens; Zheng, Li; Shisen, Xu

2009-01-01

In this article the prospect of emerging co-production and polygeneration schemes based on pre-combustion decarbonisation and options for geological storage of the CO 2 are discussed in a European and Chinese setting. Reference is made to European and Chinese undertakings - especially the COACH project that is being conducted under the auspices of the European Commission. COACH is based on principles lined up by the EU-based DYNAMIS project with reference to options for decarbonising fossil fuels within a more sustainable framework. (author)

Heat integration of an ethanol polygeneration plant based on lignocellulose: Comparing weak acid hydrolysis and enzymatic hydrolysis; Energiintegrerat etanolkombinat baserat paa lignocellulosa - Jaemfoerelse mellan svagsyrahydrolys och enzymhydrolys

Energy Technology Data Exchange (ETDEWEB)

Olsson, Marcus; Nordman, Roger; Taherzadeh, Mohammad

2011-07-01

. - Energy ratios for the reported cases show that ethanol production from cellulosic raw material ranges from 1.27 to 3.24 for the weak acid process, depending on the choice of process integration alternative, and between 3.51 to 9.56 for the enzymatic process. - The choice of process greatly affects the need for raw materials since the yields differ. The lower yield of the weak acid process means that 60% more material is needed compared with the enzymatic process. - For a future polygeneration plant it is important to consider local conditions, such as the external integration capabilities and the raw materials available. - To ensure that the process also works in a real plant, research and validation of experiments are needed in full scale facilities

27 CFR 19.912 - Small plants.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Small plants. 19.912... OF THE TREASURY LIQUORS DISTILLED SPIRITS PLANTS Distilled Spirits For Fuel Use Permits § 19.912 Small plants. Persons wishing to establish a small plant shall apply for a permit as provided in this...

Reduction of CO{sub 2} emission and oil dependency with biomass-based polygeneration

Energy Technology Data Exchange (ETDEWEB)

Joelsson, Jonas M; Gustavsson, Leif [Ecotechnology and Environmental Science, Department of Engineering and Sustainable Development, Mid Sweden University, SE-831 25 Oestersund (Sweden)

2010-07-15

We compare different options for the use of lignocellulosic biomass to reduce CO{sub 2} emission and oil use, focusing on polygeneration of biomass-based motor fuels and electricity, and discuss methodological issues related to such comparisons. The use of biomass can significantly reduce CO{sub 2} emission and oil use, but there is a trade-off between the reductions in CO{sub 2} emission and oil use. Bioelectricity from stand-alone plants replacing coal-based electricity reduced CO{sub 2} emission by 99 kg per GJ biomass input but gave no oil use reduction. Stand-alone produced methanol replacing diesel reduced the CO{sub 2} emission with 38 kg and the oil use with 0.67 GJ per GJ biomass, indicating that a potential CO{sub 2} emission reduction of 90 kg is lost per GJ oil reduced. CO{sub 2} emission and oil use reduction for alternatives co-producing fuel and electricity fall between the stand-alone alternatives. Plug-in hybrid-electric vehicles using bioelectricity reduced CO{sub 2} emission by 75-88 kg and oil use by 0.99-1.2 GJ, per GJ biomass input. Biomass can also reduce CO{sub 2} emission and/or oil use more efficiently if fossil-fuel-fired boilers or electric heating is replaced by district heating from biomass-based combined heat and power generation. This is also true if electricity or motor fuel is produced from black liquor gasification in pulp mills or if wood is used instead of concrete in building construction. Biomass gasification is an important technology to achieve large reductions, irrespective of whether CO{sub 2} emission or oil use reduction is prioritised. (author)

Exergy analysis of a combined heat and power plant with integrated lignocellulosic ethanol production

International Nuclear Information System (INIS)

Lythcke-Jørgensen, Christoffer; Haglind, Fredrik; Clausen, Lasse R.

2014-01-01

Highlights: • We model a system where lignocellulosic ethanol production is integrated with a combined heat and power (CHP) plant. • We conduct an exergy analysis for the ethanol production in six different system operation points. • Integrated operation, district heating (DH) production and low CHP loads all increase the exergy efficiency. • Separate operation has the largest negative impact on the exergy efficiency. • Operation is found to have a significant impact on the exergy efficiency of the ethanol production. - Abstract: Lignocellulosic ethanol production is often assumed integrated in polygeneration systems because of its energy intensive nature. The objective of this study is to investigate potential irreversibilities from such integration, and what impact it has on the efficiency of the integrated ethanol production. An exergy analysis is carried out for a modelled polygeneration system in which lignocellulosic ethanol production based on hydrothermal pretreatment is integrated in an existing combined heat and power (CHP) plant. The ethanol facility is driven by steam extracted from the CHP unit when feasible, and a gas boiler is used as back-up when integration is not possible. The system was evaluated according to six operation points that alternate on the following three different operation parameters: Load in the CHP unit, integrated versus separate operation, and inclusion of district heating production in the ethanol facility. The calculated standard exergy efficiency of the ethanol facility varied from 0.564 to 0.855, of which the highest was obtained for integrated operation at reduced CHP load and full district heating production in the ethanol facility, and the lowest for separate operation with zero district heating production in the ethanol facility. The results suggest that the efficiency of integrating lignocellulosic ethanol production in CHP plants is highly dependent on operation, and it is therefore suggested that the

Small hydroelectric power plants

International Nuclear Information System (INIS)

Helgesen, Boerre

2002-01-01

Small hydroelectric power plants are power plants of 1 - 10 MW. For a supplier, this is an unnatural limit. A more natural limit involves compact engine design and simplified control system. The article discusses most of the engine and electrotechnical aspects in the development, construction and operation of such a plant

Efficient production of automotive biofuels; Effektiv produktion av biodrivmedel

Energy Technology Data Exchange (ETDEWEB)

Gode, Jenny; Hagberg, Linus; Rydberg, Tomas; Raadberg, Henrik; Saernholm, Erik

2008-07-01

The report describes opportunities and consequences associated with biomass polygeneration plants, in particular the role that heat plants (HP) or combined heat and power plants (CHP) in district heating systems can play in the production of automotive biofuels. The aim of the report is to provide a knowledge base to stakeholders to help assess energy and environmental benefits associated with collaborative approaches in planning, constructing and operating energy plants. Several configurations are possible for an energy polygeneration plant, but this report focuses on configurations in which a plant for automotive biofuel production and a district heating system with HPs or CHPs have been integrated in some way in order to achieve added value. The modes of integration are several, e.g.: - Supply of process steam from the CHP to the fuel plant, by which the time of operation for the CHP can be extended; Supply of surplus heat from the fuel plant to the district heating system; Material exchange between the systems, by use of residue streams from the fuel plant as fuel in the HP/CHP; Surplus heat from the fuel plant used for drying of the solid fuel to the HP/CHP or for drying of raw material for pellets production; Co-location providing opportunities for shared infrastructure for raw material handling, service systems, utilities and/or logistics. The report principally addresses integration options of the first three types, but describes briefly also pellets production. The starting point for the analysis of integration options is the description of technologies of interest for the production of automotive biofuels. Commercially available technologies are of prime interest, but also a couple of technologies under development are included in this part of the study. In addition to outlining the process characteristics for these processes, surrounding conditions and system requirements are briefly outlined. The results are summarized in Table S1. Ethanol fermentation

Brighter for small power plants

International Nuclear Information System (INIS)

Haaland, Leif

2003-01-01

The article presents a small tunnel drilling machine aimed at using for the construction of small hydroelectric power plants and mentions briefly some advantages economically and environmentally of both the machine and the power production solution

A dynamic optimization-based architecture for polygeneration microgrids with tri-generation, renewables, storage systems and electrical vehicles

International Nuclear Information System (INIS)

Bracco, Stefano; Delfino, Federico; Pampararo, Fabio; Robba, Michela; Rossi, Mansueto

2015-01-01

Highlights: • We describe two national special projects on smart grid. • We developed dynamic decision model based on a MPC architecture. • We developed an optimization model for microgrids, for a specific case study. - Abstract: An overall architecture, or Energy Management System (EMS), based on a dynamic optimization model to minimize operating costs and CO 2 emissions is formalized and applied to the University of Genova Savona Campus test-bed facilities consisting of a Smart Polygeneration Microgrid (SPM) and a Sustainable Energy Building (SEB) connected to such microgrid. The electric grid is a three phase low voltage distribution system, connecting many different technologies: three cogeneration micro gas turbines fed by natural gas, a photovoltaic field, three cogeneration Concentrating Solar Powered (CSP) systems (equipped with Stirling engines), an absorption chiller equipped with a storage tank, two types of electrical storage based on batteries technology (long term Na–Ni and short term Li-Ion ion), two electric vehicles charging stations, other electrical devices (inverters and smart metering systems), etc. The EMS can be used both for microgrids approximated as single bus bar (or one node) and for microgrids in which all buses are taken into account. The optimal operation of the microgrid is based on a central controller that receives forecasts and data from a SCADA system and that can schedule all dispatchable plants in the day ahead or in real time through an approach based on Model Predictive Control (MPC). The architecture is tested and applied to the case study of the Savona Campus

Modular plants for small deposits

International Nuclear Information System (INIS)

Josa, J.M.; Moral, A.; Otero, J.L.; Suarez, E.

1985-01-01

The large investment required to recover uranium from small deposits is the greatest obstacle to their economic development. Various concepts (caravan mill, pure mill or semimobile mill) have been elaborated in different countries. Studies have also been made in Spain to develop a simple and economic flowsheet suitable for the beneficiation of small uranium deposits. An acid heap-leaching and solvent extraction process was chosen because there is already a great deal of experience of it in Spain. Modifications were necessary to make the equipment easy to transport and also to have a low and reusable investment when this flowsheet is used for small deposits. The aim was to develop a modular plant with all the elements fitted in compact units that needs little site preparation and little time and effort to connect the units. A standard small portable crushing plant can be borrowed and the mining operation and heap construction can be put to contract. There is a solvent extraction unit (150 m 3 /d) in continuous operation (24 h/d) and concentrate precipitation and handling facilities. The whole of the equipment is standard and as light as possible. Little civil engineering is required and the erection of the plant only needs a few months. The uranium capacity of these modular plants is between 35 and 50 t U 3 O 8 /a. Special consideration has been paid to regulations and the environmental aspects. (author)

Endogenous small RNAs and antibacterial immunity in plants.

Science.gov (United States)

Jin, Hailing

2008-08-06

Small RNAs are non-coding regulatory RNA molecules that control gene expression by mediating mRNA degradation, translational inhibition, or chromatin modification. Virus-derived small RNAs induce silencing of viral RNAs and are essential for antiviral defense in both animal and plant systems. The role of host endogenous small RNAs on antibacterial immunity has only recently been recognized. Host disease resistance and defense responses are achieved by activation and repression of a large array of genes. Certain endogenous small RNAs in plants, including microRNAs (miRNAs) and small interfering RNAs (siRNAs), are induced or repressed in response to pathogen attack and subsequently regulate the expression of genes involved in disease resistance and defense responses by mediating transcriptional or post-transcriptional gene silencing. Thus, these small RNAs play an important role in gene expression reprogramming in plant disease resistance and defense responses. This review focuses on the recent findings of plant endogenous small RNAs in antibacterial immunity.

Environmental certification for small hydropower plants

International Nuclear Information System (INIS)

Truffer, B.; Meier, W.; Vollenweider, S.; Seiler, B.; Dettli, R.

2001-01-01

This report for the Swiss Federal Institute for Environmental Science and Technology describes product-differentiation options for small hydropower plant in Switzerland and proposes a form of differentiation based on ecological characteristics as a promising market strategy. The labels created in various countries to assure customers of the environmental compatibility of 'green' power production are looked at. In particular, the implications for small hydropower plant associated with the Swiss green power labelling procedure introduced by the Association for the Promotion of Environmentally Sound Electricity (VUE) are discussed. The report proposes a simplified procedure for these small power stations and presents a sample calculation for the overall costs of certification. The report is rounded off with four detailed case studies in which the necessary upgrades to the plant and associated costs are discussed in detail

Plant management tools tested with a small-scale distributed generation laboratory

International Nuclear Information System (INIS)

Ferrari, Mario L.; Traverso, Alberto; Pascenti, Matteo; Massardo, Aristide F.

2014-01-01

Highlights: • Thermal grid innovative layouts. • Experimental rig for distributed generation. • Real-time management tool. • Experimental results for plant management. • Comparison with results from an optimization complete software. - Abstract: Optimization of power generation with smart grids is an important issue for extensive sustainable development of distributed generation. Since an experimental approach is essential for implementing validated optimization software, the TPG research team of the University of Genoa has installed a laboratory facility for carrying out studies on polygeneration grids. The facility consists of two co-generation prime movers based on conventional technology: a 100 kWe gas turbine (mGT) and a 20 kWe internal combustion engine (ICE). The rig high flexibility allows the possibility of integration with renewable-source based devices, such as biomass-fed boilers and solar panels. Special attention was devoted to thermal distribution grid design. To ensure the possibility of application in medium-large districts, composed of several buildings including energy users, generators or both, an innovative layout based on two ring pipes was examined. Thermal storage devices were also included in order to have a complete hardware platform suitable for assessing the performance of different management tools. The test presented in this paper was carried out with both the mGT and the ICE connected to this innovative thermal grid, while users were emulated by means of fan coolers controlled by inverters. During this test the plant is controlled by a real-time model capable of calculating a machine performance ranking, which is necessary in order to split power demands between the prime movers (marginal cost decrease objective). A complete optimization tool devised by TPG (ECoMP program) was also used in order to obtain theoretical results considering the same machines and load values. The data obtained with ECoMP were compared with the

Competitive analysis of small hydroelectric power plants

International Nuclear Information System (INIS)

Assad, L.S.; Placido, R.

1990-01-01

The agreement between CPFL/UNICAMP/EFEI for developing energetic planning of Small Hydroelectric Power Plants construction is described. Some notions for showing the more economic alternative between decide by Small Hydroelectric Power Plants construction and continue supply the market by inter ligated system generation are shown in this stage of the agreement. (author)

Integration of hydrothermal carbonization and a CHP plant: Part 2 –operational and economic analysis

International Nuclear Information System (INIS)

Saari, Jussi; Sermyagina, Ekaterina; Kaikko, Juha; Vakkilainen, Esa; Sergeev, Vitaly

2016-01-01

Wood-fired combined heat and power (CHP) plants are a proven technology for producing domestic, carbon-neutral heat and power in Nordic countries. One drawback of CHP plants is the low capacity factors due to varying heat loads. In the current economic environment, uncertainty over energy prices creates also uncertainty over investment profitability. Hydrothermal carbonization (HTC) is a promising thermochemical conversion technology for producing an improved, more versatile wood-based fuel. Integrating HTC with a CHP plant allows simplifying the HTC process and extending the CHP plant operating time. An integrated polygeneration plant producing three energy products is also less sensitive to price changes in any one product. This study compares three integration cases chosen from the previous paper, and the case of separate stand-alone plants. The best economic performance is obtained using pressurized hot water from the CHP plant boiler drum as HTC process water. This has the poorest efficiency, but allows the greatest cost reduction in the HTC process and longest CHP plant operating time. The result demonstrates the suitability of CHP plants for integration with a HTC process, and the importance of economic and operational analysis considering annual load variations in sufficient detail. - Highlights: • Integration of wood hydrothermal carbonization with a small CHP plant studied. • Operation and economics of three concepts and stand-alone plants are compared. • Sensitivity analysis is performed. • Results show technical and thermodynamic analysis inadequate and misleading alone. • Minimizing HTC investment, extending CHP operating time important for profitability.

Small-scale power plant potential in Finland

International Nuclear Information System (INIS)

Helynen, S.

1993-01-01

The presentation discusses the small-scale power plant potential in Finland. The study of the potential is limited to W-scale power plants producing both electric power and heat using solid fuels. The basic power plant dimensioning and electric power load determination is based on traditional boiler and gas turbine technology. The possible sites for power plants are communities using district heating, and industrialized sites needing process steam or heat. In 1990 70 % (17 TWh) of district heat was produced by gas turbines. Ten communities have an own back-pressure power plant, and 40 communities buy heat from industrial plants, owing back-pressure power generation. Additionally about 40 communes buy district heat from companies, owned by power companies and industry. Estimates of small-scale power plant potential has been made plant wise on the basis of district heat loads and industrial heat needs. The scale of the plants has been limited to scale 3 MWe or more. The choosing of the fuel depends on the local conditions. The cheapest indigenous fuels in many communes are industrial wood wastes, and both milled and sod peat. The potential of steam technology based small-scale power plants has been estimated to be about 50 plants in 1992/1993, the total power of which is 220-260 MW. The largest estimate is base situation, in which there would be energy cooperation between the communes and industry. The fuel used by the power plants would be about 5.4-6.6 TWh/a corresponding to 270-330 million FIM/a. The total investment costs of the plants would be about 2.0 billion FIM. The plants would employ about 250 persons, and the fuel supply (wood or peat) about 100 persons

Comparative study of wet and dry torrefaction of corn stalk and the effect on biomass pyrolysis polygeneration.

Science.gov (United States)

Wang, Xianhua; Wu, Jing; Chen, Yingquan; Pattiya, Adisak; Yang, Haiping; Chen, Hanping

2018-06-01

Wet torrefaction (WT) possesses some advantages over dry torrefaction (DT). In this study, a comparative analysis of torrefied corn stalk from WT and DT was conducted along with an investigation of their pyrolysis properties under optimal conditions for biomass pyrolysis polygeneration. Compared with DT, WT removed 98% of the ash and retained twice the amount of hydrogen. The impacts of DT and WT on the biomass macromolecular structure was also found to be different using two-dimensional perturbation correlation infrared spectroscopy (2D-PCIS). WT preserved the active hydroxyl groups and rearranged the macromolecule structure to allow cellulose to be more ordered, while DT removed these active hydroxyl groups and formed inter-crosslinking structures in macromolecules. Correspondingly, the bio-char yield after WT was lower than DT but the bio-char quality was upgraded due to high ash removal. Furthermore, higher bio-oil yield, higher sugar content, and higher H 2 generation, were obtained after WT. Copyright © 2018 Elsevier Ltd. All rights reserved.

Small hydroelectric power plants - shelf goods or tailor-made?

International Nuclear Information System (INIS)

Aas, Trond R.

2002-01-01

If small hydroelectric power plants are defined to be hydroelectric power plants of up to a few 1000 kW, they should be shelf goods because of cost considerations. Design of small hydroelectric power plants is a many-sided optimization task, on a level with constructing larger hydro power plants. But the budget for a small hydro power plant does not permit any comprehensive evaluations. The most important costs are the one-time costs in the form of investments and the following annual costs in the form of operation and maintenance, and losses. Financing costs are not considered in this article

Techno-economic assessment for the integration into a multi-product plant based on cascade utilization of geothermal energy

International Nuclear Information System (INIS)

Rubio-Maya, Carlos; Pastor Martínez, Edgar; Romero, Carlos E.; Ambriz Díaz, Víctor M.; Pacheco-Ibarra, J. Jesús

2016-01-01

Highlights: • Cascade utilization of low- and mid-temperature geothermal energy is presented. • The system consists of three thermal levels producing power, ice and useful heat. • A techno-economic analysis is performed evaluating energy and economic benefits. • A simple optimization algorithm was developed to optimize system benefits. • Inconvenience of low thermal efficiency and high capital cost of ORC were overcome. - Abstract: The Organic Rankine Cycle (ORC) is a technology that has reached maturity in cogeneration or waste heat applications. However, due to low thermal efficiency and high capital cost of ORC machines, geothermal-based ORC applications represent only a small percent sharing of the geothermal power capacity worldwide. Several countries have reported a great potential of low- and mid-temperature geothermal energy, representing an opportunity to explore a more efficient ORC integration into non-conventional applications of geothermal energy. One alternative, resembling the polygeneration concept, is known as cascade utilization of geothermal energy, where different energy outputs or products can be obtained at the same time, while improving thermal and economic performance. In this paper, a techno-economic analysis for the selection of small capacity ORC machines and absorption chillers (for ice production), to be integrated into a polygeneration plant that makes use of geothermal energy in a cascade arrangement, is presented. A simple cascade system that consists of three sequential thermal levels, producing simultaneously power, ice and useful heat is proposed, considering typical temperatures of geothermal zones in Mexico. A simple optimization algorithm, based on energy and economic models, including binary variables and manufacturer’s data, was developed to evaluate and determine optimal ORC and absorption chiller units. Results show, firstly, that inconvenience of low thermal efficiency and high capital cost of ORC machines can

Critical factors for profitable combined production of heat, power and biofuels; Kritiska faktorer foer loensam produktion i bioenergikombinat

Energy Technology Data Exchange (ETDEWEB)

Nohlgren, Ingrid; Gunnarsson, Emma; Lundqvist, Per; Stigander, Haakan; Widmark, Annika (AaF, Stockholm (Sweden))

2012-02-15

During the last 5-10 years, research and development efforts have been made in the field of polygeneration of heat and power with production of 'other green' products such as transport fuels or wood pellets. The driving force for heat and power producers is the potential of increased profitability through additional sales of heat. The driving force for wood pellet and some transport fuel producers is the potential of low cost process steam or heat. However, in the case of gasification based transport fuel production processes the situation is different. The process generates a surplus of heat, which can benefit from the proximity of a district heating net. In addition, some polygeneration combinations could provide other advantages such as more efficient raw material handling. Together with these driving forces, the EU renewable energy directive (which targets 10 % renewable energy use in the transport sector by 2020), shows that the market for production of renewable transport fuel is expanding. To refine Swedish biomass resources to more highly valuable products such as wood pellets or renewable transport fuels would maintain industry and employment opportunities within Sweden and at the same time fulfils the international and national climate targets. The overall aim with this project is to describe the factors which are crucial for the opportunity for profitable polygeneration of heat, power and wood pellets or renewable transport fuels and how these factors influence the location of such a plant within Sweden. The important factors can be categorized as: (1) Supply of raw material, (2) distribution of raw material and products, (3) Demand of products and (4) Integration between the different plants. In this project, only general aspects are described and should be seen as guidance for the industry (both energy and forest industry) which has an interest in polygeneration. The project gives an overview of different possibilities, opportunities and

Exergetic and exergoeconomic analysis of a novel hybrid solar–geothermal polygeneration system producing energy and water

International Nuclear Information System (INIS)

Calise, Francesco; D’Accadia, Massimo Dentice; Macaluso, Adriano; Piacentino, Antonio; Vanoli, Laura

2016-01-01

Highlights: • Exergetic and exergoeconomic analysis of hybrid renewable system is presented. • The system provides electric, thermal and cooling energy and desalinated water. • Exergy efficiency varies between 40–50% in the winter and 16–20% in the summer. • Electricity and fresh water costs vary between 15–17 and 57–60 c€/kW h_e_x. • Chilled and hot water costs vary between 18.6–18.9 and 1.6–1.7 c€/kW h_e_x. - Abstract: A dynamic simulation model of a novel solar–geothermal polygeneration system and the related exergetic and exergoeconomic analyses are presented in this paper. The plant is designed in order to supply electrical, thermal and cooling energy and fresh water for a small community, connected to a district heating and cooling network. The hybrid system is equipped with an Organic Rankine Cycle fueled by medium-enthalpy geothermal energy and by a Parabolic Trough Collector solar field. Geothermal brine is also used for space heating and cooling purposes. Finally, geothermal fluid supplies heat to a Multi-Effect Distillation unit, producing also desalinized water from seawater. Dynamic simulations were performed in order to design the system. The overall simulation model, implemented in TRNSYS environment, includes detailed algorithms for the simulation of system components. Detailed control strategies were included in the model in order to properly manage the system. An exergetic and exergoeconomic analysis is also implemented. The exergetic analysis allows to identify all the aspects that affect the global exergy efficiency, in order to suggest possible system enhancements. The accounting of exergoeconomic costs aims at establishing a monetary value to all material and energy flows, then providing a reasonable basis for price allocation. The analysis is applied to integral values of energy and a comparison of results between summer and winter season is performed. Results are analyzed on different time bases presenting

Small and medium-sized nuclear power plants

International Nuclear Information System (INIS)

Schmidt, R.

1986-01-01

Small and medium-sized nuclear power plants have long been under discussion as possible applications of nuclear power in countries with small transmission grid systems, in threshold countries and developing countries, and under special local supply conditions. IAEA has condensed and promoted this interest and tried to establish the demand, and possibilities of meeting it, in special events and campaigns. In recent years, considerable interest was registered even in industrialized countries, but here specially for heating and process heat generation applications and for special purposes and, in medium-sized units, also for combined supplies of electricity and heat. This corresponds to special reactor and plant concepts, some of which have already been developed to a stage at which construction work could begin. The analysis presented deals with necessary preconditions on the sides of the users and the vendors, with problems of economy, infrastructure and financing and with the market prospects of small nuclear power plants. (orig./HP) [de

Process analysis of an oxygen lean oxy-fuel power plant with co-production of synthesis gas

International Nuclear Information System (INIS)

Normann, Fredrik; Thunman, Henrik; Johnsson, Filip

2009-01-01

This paper investigates new possibilities and synergy effects for an oxy-fuel fired polygeneration scheme (transportation fuel and electricity) with carbon capture and co-firing of biomass. The proposed process has the potential to make the oxy-fuel process more effective through a sub-stoichiometric combustion in-between normal combustion and gasification, which lowers the need for oxygen within the process. The sub-stoichiometric combustion yields production of synthesis gas, which is utilised in an integrated synthesis to dimethyl ether (DME). The process is kept CO 2 neutral through co-combustion of biomass in the process. The proposed scheme is simulated with a computer model with a previous study of an oxy-fuel power plant as a reference process. The degree of sub-stoichiometric combustion, or amount of synthesis gas produced, is optimised with respect to the overall efficiency. The maximal efficiency was found at a stoichiometric ratio just below 0.6 with the efficiency for the electricity producing oxy-fuel process of 0.35 and a DME process efficiency of 0.63. It can be concluded that the proposed oxygen lean combustion process constitutes a way to improve the oxy-fuel carbon capture processes with an efficient production of DME in a polygeneration process

Maturation processes and structures of small secreted peptides in plants

Directory of Open Access Journals (Sweden)

Ryo eTabata

2014-07-01

Full Text Available In the past decade, small secreted peptides have proven to be essential for various aspects of plant growth and development, including the maintenance of certain stem cell populations. Most small secreted peptides identified in plants to date are recognised by membrane-localized receptor kinases, the largest family of receptor proteins in the plant genome. This peptide-receptor interaction is essential for initiating intracellular signalling cascades. Small secreted peptides often undergo post-translational modifications and proteolytic processing to generate the mature peptides. Recent studies suggest that, in contrast to the situation in mammals, the proteolytic processing of plant peptides involves a number of complex steps. Furthermore, NMR-based structural analysis demonstrated that post-translational modifications induce the conformational changes needed for full activity. In this mini review, we summarise recent advances in our understanding of how small secreted peptides are modified and processed into biologically active peptides and describe the mature structures of small secreted peptides in plants.

Environmental certification for small hydropower plants; Umweltzertifizierung Kleinwasserkraftwerke

Energy Technology Data Exchange (ETDEWEB)

Truffer, B.; Meier, W.; Vollenweider, S. [Eidgenoessische Anstalt fuer Wasserversorgung, Abwasserreinigung und Gewaesserschutz (EAWAG), Kastanienbaum (Switzerland); Seiler, B.; Dettli, R. [Econcept AG, Zuerich (Switzerland)

2001-07-01

This report for the Swiss Federal Institute for Environmental Science and Technology describes product-differentiation options for small hydropower plant in Switzerland and proposes a form of differentiation based on ecological characteristics as a promising market strategy. The labels created in various countries to assure customers of the environmental compatibility of 'green' power production are looked at. In particular, the implications for small hydropower plant associated with the Swiss green power labelling procedure introduced by the Association for the Promotion of Environmentally Sound Electricity (VUE) are discussed. The report proposes a simplified procedure for these small power stations and presents a sample calculation for the overall costs of certification. The report is rounded off with four detailed case studies in which the necessary upgrades to the plant and associated costs are discussed in detail.

Operating of Small Wind Power Plants with Induction Generators

OpenAIRE

Jakub Nevrala; Stanislav Misak

2008-01-01

This paper describes different systems of small wind power plants with induction generators used in the Czech Republic. Problems of wind power plants running with induction generators are solved within partial target of the research project MSM 6198910007. For small wind power plants is used induction motor as a generator. Parameters of the name plate of motor must be resolved for generator running on measuring base. These generators are running as a separately working generators or generator...

Profitability and sustainability of small - medium scale palm biodiesel plant

Science.gov (United States)

Solikhah, Maharani Dewi; Kismanto, Agus; Raksodewanto, Agus; Peryoga, Yoga

2017-06-01

The mandatory of biodiesel application at 20% blending (B20) has been started since January 2016. It creates huge market for biodiesel industry. To build large-scale biodiesel plant (> 100,000 tons/year) is most favorable for biodiesel producers since it can give lower production cost. This cost becomes a challenge for small - medium scale biodiesel plants. However, current biodiesel plants in Indonesia are located mainly in Java and Sumatra, which then distribute biodiesel around Indonesia so that there is an additional cost for transportation from area to area. This factor becomes an opportunity for the small - medium scale biodiesel plants to compete with the large one. This paper discusses the profitability of small - medium scale biodiesel plants conducted on a capacity of 50 tons/day using CPO and its derivatives. The study was conducted by performing economic analysis between scenarios of biodiesel plant that using raw material of stearin, PFAD, and multi feedstock. Comparison on the feasibility of scenarios was also conducted on the effect of transportation cost and selling price. The economic assessment shows that profitability is highly affected by raw material price so that it is important to secure the source of raw materials and consider a multi-feedstock type for small - medium scale biodiesel plants to become a sustainable plant. It was concluded that the small - medium scale biodiesel plants will be profitable and sustainable if they are connected to palm oil mill, have a captive market, and are located minimally 200 km from other biodiesel plants. The use of multi feedstock could increase IRR from 18.68 % to 56.52 %.

Large and small baseload power plants: Drivers to define the optimal portfolios

International Nuclear Information System (INIS)

Locatelli, Giorgio; Mancini, Mauro

2011-01-01

Despite the growing interest in Small Medium sized Power Plants (SMPP) international literature provides only studies related to portfolios of large plants in infinite markets/grids with no particular attention given to base load SMPP. This paper aims to fill this gap, investigating the attractiveness of SMPP portfolios respect to large power plant portfolios. The analysis includes nuclear, coal and combined cycle gas turbines (CCGT) of different plant sizes. The Mean Variance Portfolio theory (MVP) is used to define the best portfolio according to Internal Rate of Return (IRR) and Levelised Unit Electricity Cost (LUEC) considering the life cycle costs of each power plant, Carbon Tax, Electricity Price and grid dimension. The results show how large plants are the best option for large grids, while SMPP are as competitive as large plants in small grids. In fact, in order to achieve the highest profitability with the lowest risk it is necessary to build several types of different plants and, in case of small grids, this is possible only with SMPP. A further result is the application of the framework to European OECD countries and the United States assessing their portfolios. - Highlights: ► The literature about power plant portfolios does not consider small grids and IRR. ► We evaluated Base load portfolios respect to IRR and LUEC. ► We assessed the influence of grid and plant size, CO 2 cost and Electricity Price. ► Large plants are optimal for large markets even if small plants have similar IRR. ► Small plants are suitable to diversify portfolios in small grids reducing the risk.

Risk management method for small photovoltaic plants

Directory of Open Access Journals (Sweden)

Kirova Milena

2016-09-01

Full Text Available Risk management is necessary for achieving the goals of the organization. There are many methods, approaches, and instruments in the literature concerning risk management. However, these are often highly specialized and transferring them to a different field can prove difficult. Therefore, managers often face situations where they have no tools to use for risk management. This is the case with small photovoltaic plants (according to a definition by the Bulgarian State Energy and Water Regulatory Commission small applies to systems with a total installed power of 200 kWp. There are some good practices in the energy field for minimizing risks, but they offer only partial risk prevention and are not sufficient. Therefore a new risk management method needs to be introduced. Small photovoltaic plants offer plenty of advantages in comparison to the other renewable energy sources which makes risk management in their case more important. There is no classification of risks for the exploitation of small photovoltaic systems in the available literature as well as to what degree the damages from those risks could spread. This makes risk analysis and evaluation necessary for obtaining information which could aid taking decisions for improving risk management. The owner of the invested capital takes a decision regarding the degree of acceptable risk for his organization and it must be protected depending on the goals set. Investors in small photovoltaic systems need to decide to what degree the existing risks can influence the goals previously set, the payback of the investment, and what is the acceptable level of damages for the investor. The purpose of this work is to present a risk management method, which currently does not exist in the Bulgaria, so that the risks and the damages that could occur during the exploitation of small photovoltaic plants could be identified and the investment in such technology – justified.

SMALL HYDRO PLANTS IN LAND USE SYSTEM PLANNING IN POLAND

Directory of Open Access Journals (Sweden)

Anita Bernatek

2014-10-01

Full Text Available Small hydropower plants are present in the land use system planning in Poland. At the national level the important role of spatial planning in the development of renewable energy was highlighted, included small hydroplants. However, it seems that at the regional level this demand has not been realized. The necessity of developing small hydroplants as a renewable energy was highlighted, but negative environmental impact was not indicated. At local level legal instrument of small hydropower plants is specified.

Small-Scale Combined Heat and Power Plants Using Biofuels

Energy Technology Data Exchange (ETDEWEB)

Salomon-Popa, Marianne [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Energy Technology

2002-11-01

In this time period where energy supply and climate change are of special concern, biomass-based fuels have attracted much interest due to their plentiful supply and favorable environmental characteristics (if properly managed). The effective capture and continued sustainability of this renewable resource requires a new generation of biomass power plants with high fuel energy conversion. At the same time, deregulation of the electricity market offers new opportunities for small-scale power plants in a decentralized scheme. These two important factors have opened up possibilities for small-scale combined heat and power (CHP) plants based on biofuels. The objective of this pre-study is to assess the possibilities and technical limitations for increased efficiency and energy utilization of biofuels in small size plants (approximately 10 MWe or lower). Various energy conversion technologies are considered and proven concepts for large-scale fossil fuel plants are an especially important area. An analysis has been made to identify the problems, technical limitations and different possibilities as recognized in the literature. Beyond published results, a qualitative survey was conducted to gain first-hand, current knowledge from experts in the field. At best, the survey results together with the results of personal interviews and a workshop on the role of small-scale plants in distributed generation will serve a guideline for future project directions and ideas. Conventional and novel technologies are included in the survey such as Stirling engines, combustion engines, gas turbines, steam turbines, steam motors, fuel cells and other novel technologies/cycles for biofuels. State-of-the-art heat and power plants will be identified to clarify of the advantages and disadvantages as well as possible obstacles for their implementation.

Refurbishment of small hydropower plants in Romania; Sanierung von Kleinwasserkraftwerken in Rumaenien

Energy Technology Data Exchange (ETDEWEB)

Gmeinbauer, Joerg [Wien Energie GmbH, Wien (Austria)

2010-07-01

In 2008 Wien Energie subsidiary Wienstrom GmbH participated in three public auctions of Hidroelectrica S.A. for the sale of old small hydro power plants in Romania. Together with strategic partners Wienstrom could successfully compete against local and international competition and acquired 31 small hydro power plants with a total installed capacity of around 20 MW. The plants were integrated into the newly established Vienna Energy Forta Naturala Srl. and are being completely refurbished at the moment. Wien Energie consequently is already the third largest operator of small hydro power plants in Romania. (orig.)

Estimation of small-scale hydroelectric power plant costs

International Nuclear Information System (INIS)

Santos, Afonso Henriques Moreira; Silva, Benedito Claudio da; Magalhaes, Ricardo Nogueira

2010-01-01

Changes in Brazilian energy scenario through last years such as increase of demand and search for clean and economically feasible renewable energy sources, has stimulated investors to small hydro power plants (SHP) sector. Such characteristics together with several economic incentives, legal and regulatory mechanisms also, have helped and stimulated building of new plants of this kind and have attracted a great number of investors to this sector. Study of costs analysis and feasibility of investments is a study which has been used since long time in SHP business market as several preliminary studies previous to civil project have significant costs which lead us to count with a feasibility analysis from the very beginning of studies, exactly what is suggested in the present methodology. Such feasibility analysis, in the common patterns where basic unit costs of each input remain outstanding, would be very complex due to great difficulty in obtaining information at initial phase of project. In this direction this study brings a contribution for investors as well as for designers of small hydro power plants since it outlines a link between physical and energetic characteristics of small hydro power plant in its total cost. Such link is based in available physical characteristics in initial phase of the project, making possible a previous comparison between arrangements of a central or even the comparison of return of investment between different plants. The resulting benefit being the possibility of choosing centrals with greater economic feasibility disregarding bad undertakings or arrangements with more expressive cost. Final result gives a better delay in return of investment, helps in power, arrangements more optimized and in saving time as well, reducing costs of undertakings. Due to large number of SHP arrangements, we chose for this study the most common in Brazil, plant of medium and large fall, shunting line balance chimney and low pressure conduit. (author)

Operating of Small Wind Power Plants with Induction Generators

Directory of Open Access Journals (Sweden)

Jakub Nevrala

2008-01-01

Full Text Available This paper describes different systems of small wind power plants with induction generators used in the Czech Republic. Problems of wind power plants running with induction generators are solved within partial target of the research project MSM 6198910007. For small wind power plants is used induction motor as a generator. Parameters of the name plate of motor must be resolved for generator running on measuring base. These generators are running as a separately working generators or generators connected to the power grid. Methods of control these systems as a separately working, directly connecting to power grid, control by frequency converter and wiring by synchronous cascade are confronted on the measuring base too.

Standardized small diesel power plants for rural electrification in Tanzania

International Nuclear Information System (INIS)

Holmqvist, A.; Soerman, J.; Gullberg, M.; Kjellstroem, B.

1993-01-01

This study focuses on small townships where the forecasted power demand stays below 500 kW during the ten first years. Case study calculations were made where two hypothetical load centres form the base. Each load centre is assumed to be supplied by two alternative standardized diesel power plants. One option is a power plant consisting of two medium speed (750 rpm) generator sets, one always on stand-by. Alternatively, a power plant consisting of three high speed (1500 rpm) generator sets is evaluated for each hypothetical load centre. The calculations clearly show that the high speed, three unit option comes out cheaper than the two unit, medium speed option in all the considered cases. The fuel costs per kWh generated are almost the same in all the cases studied, i.e. between 6 and 7 US cents. The medium speed engine tends to consume more fuel per kWh generated than the high speed, as it runs more often on part load. Consequently, the fuel costs will be slightly higher for this option. It is also of interest to compare the plant failure rate of the two options. In this study no proper probability evaluation has been made, but some general reflections can be worth considering. The availability of spare parts in Tanzania is doubtful. Many small diesel power plants presently operating have to wait indefinitely, when a failure appears that requires spare parts. As long as the individual sets have the same, or nearly the same failure rate, a three unit plant has lower probability for total loss of generating capacity than a two unit plant. The main conclusion of this evaluation is that for electricity generation in rural Tanzanian villages, power plants with three small, high speed generator sets are preferable to plants with two, medium speed generator sets. A power plant made out of small sets requires less capital, consumes less fuel and is not as likely to loose its generating capacity totally. 16 refs, 10 figs, 21 tabs

A simple and efficient method for isolating small RNAs from different plant species

Directory of Open Access Journals (Sweden)

de Folter Stefan

2011-02-01

Full Text Available Abstract Background Small RNAs emerged over the last decade as key regulators in diverse biological processes in eukaryotic organisms. To identify and study small RNAs, good and efficient protocols are necessary to isolate them, which sometimes may be challenging due to the composition of specific tissues of certain plant species. Here we describe a simple and efficient method to isolate small RNAs from different plant species. Results We developed a simple and efficient method to isolate small RNAs from different plant species by first comparing different total RNA extraction protocols, followed by streamlining the best one, finally resulting in a small RNA extraction method that has no need of first total RNA extraction and is not based on the commercially available TRIzol® Reagent or columns. This small RNA extraction method not only works well for plant tissues with high polysaccharide content, like cactus, agave, banana, and tomato, but also for plant species like Arabidopsis or tobacco. Furthermore, the obtained small RNA samples were successfully used in northern blot assays. Conclusion Here we provide a simple and efficient method to isolate small RNAs from different plant species, such as cactus, agave, banana, tomato, Arabidopsis, and tobacco, and the small RNAs from this simplified and low cost method is suitable for downstream handling like northern blot assays.

Evaluation of small hydropower plants in Latin America and the Caribbean

International Nuclear Information System (INIS)

Pardo-Gomez, R.

1991-01-01

Latin America and the Caribbean Region has a long-standing tradition of small hydropower plant development. In the 1890s the first plants were installed in the Region, and in the first half of this century pioneering efforts were made to develop the technology. The major reason was the technical modernization of agriculture (coffee, cacao, sugar, etc.) and small-scale mining, which led to increased energy demand in isolated areas when the electrification process was just beginning in the region. However, interest in small hydropower plants (SHP) waned because of technological improvements, enhanced efficiency, lower purchase prices and installation costs of gasoline engines, and the expansion of interconnected power systems

Small molecule probes for plant cell wall polysaccharide imaging

Directory of Open Access Journals (Sweden)

Ian eWallace

2012-05-01

Full Text Available Plant cell walls are composed of interlinked polymer networks consisting of cellulose, hemicelluloses, pectins, proteins, and lignin. The ordered deposition of these components is a dynamic process that critically affects the development and differentiation of plant cells. However, our understanding of cell wall synthesis and remodeling, as well as the diverse cell wall architectures that result from these processes, has been limited by a lack of suitable chemical probes that are compatible with live-cell imaging. In this review, we summarize the currently available molecular toolbox of probes for cell wall polysaccharide imaging in plants, with particular emphasis on recent advances in small molecule-based fluorescent probes. We also discuss the potential for further development of small molecule probes for the analysis of cell wall architecture and dynamics.

Facile synthesis of polypyrrole functionalized nickel foam with catalytic activity comparable to Pt for the poly-generation of hydrogen and electricity

Science.gov (United States)

Tang, Tiantian; Li, Kan; Shen, Zhemin; Sun, Tonghua; Wang, Yalin; Jia, Jinping

2016-01-01

Polypyrrole functionalized nickel foam is facilely prepared through the potentiostatic electrodeposition. The PPy-functionalized Ni foam functions as a hydrogen-evolution cathode in a rotating disk photocatalytic fuel cell, in which hydrogen energy and electric power are generated by consuming organic wastes. The PPy-functionalized Ni foam cathode exhibits stable catalytic activities after thirteen continuous runs. Compared with net or plate structure, the Ni foam with a unique three-dimensional reticulate structure is conducive to the electrodeposition of PPy. Compared with Pt-group electrode, PPy-coated Ni foam shows a satisfactory catalytic performance for the H2 evolution. The combination of PPy and Ni forms a synergistic effect for the rapid trapping and removal of proton from solution and the catalytic reduction of proton to hydrogen. The PPy-functionalized Ni foam could be applied in photocatalytic and photoelectrochemical generation of H2. In all, we report a low cost, high efficient and earth abundant PPy-functionalized Ni foam with a satisfactory catalytic activities comparable to Pt for the practical application of poly-generation of hydrogen and electricity.

Very small HTGR nuclear power plant concepts for special terrestrial applications

International Nuclear Information System (INIS)

McDonald, C.F.; Goodjohn, A.J.

1983-01-01

The role of the very small nuclear power plant, of a few megawatts capacity, is perceived to be for special applications where an energy source as required but the following prevail: 1) no indigenous fossil fuel source, in long transport distances that add substantially to the cost of oil, coal in gas, and 3) secure long-term power production for defense applications with freedom from fuel supply lines. A small High Temperature Gas-Cooled reactor (HTGR) plant could provide the total energy needs for 1) a military installation, 2) an island base of strategic significance, 3) an industrial community or 4) an urban area. The small HTGR is regarded as a fixed-base installation (as opposed to a mobile system). All of the major components would be factory fabricated and transported to the site where emphasis would be placed on minimizing the construction time. The very small HTGR plant, currently in an early stage of design definition, has the potential for meeting the unique needs of the small energy user in both the military and private sectors. The plant may find acceptance for specialized applications in the industrialized nations and to meet the energy needs of developing nations. Emphasis in the design has been placed on safety, simplicity and compactness

Optimal designs of small CHP plants in a market with fluctuating electricity prices

International Nuclear Information System (INIS)

Lund, H.; Andersen, A.N.

2005-01-01

Combined Heat and Power production (CHP) are essential for implementation of the climate change response objectives in many countries. In an introduction period, small CHP plants have typically been offered fixed electricity prices, but in many countries, such pricing conditions are now being replaced by spot market prices. Consequently, new methodologies and tools for the optimisation of small CHP plant designs are needed. The small CHP plants in Denmark are already experienced in optimising their electricity production against the triple tariff, which has existed for almost 10 years. Consequently, the CHP plants have long term experience in organising when to switch on and off the CHP units in order to optimise their profit. Also, the CHP owners have long term experience in designing their plants. For instance, small CHP plants in Denmark have usually invested in excess capacity on the CHP units in combination with heat storage capacity. Thereby, the plants have increased their performance in order to optimise revenues. This paper presents the Danish experience with methodologies and software tools, which have been used to design investment and operation strategies for almost all small CHP plants in Denmark during the decade of the triple tariff. Moreover, the changes in such methodologies and tools in order to optimise performance in a market with fluctuating electricity prices are presented and discussed

Exploring Aspects of Strategic Management for a Small Plant Bakery

OpenAIRE

Leary, PA; Bell, GA; Thomson, EM

2017-01-01

This paper explores the use some aspects of strategic management in order to inform a small plant bakery. We briefly review key theories underpinning business strategy and its implementation. A small plant bakery in the UK was analysed, identifying its Critical Success Factors (CSF) and Key Performance Indicators (KPI) comparing these with previous periods and other successful bakery businesses. Furthermore, the case study strategy is used to guide this research. We seek to determine if criti...

A trend to small nuclear power plants?

International Nuclear Information System (INIS)

Lameira, Fernando Soares

2000-01-01

The release of fossil fuel greenhouse gases and the depletion of cheap oil reserves outside the Persic Gulf suggest a promising scenario for the future of nuclear power. But the end of the Cold War, the crisis of the state, axiological questions and globalization may lead to a marked for small power plants. The purpose of this paper is to analyze these factors, since they are not always considered all together in the future scenarios for nuclear power. It is concluded that the current evolutionary trend of nuclear power projects toward big plants may become one of the main barriers for the introduction of new plants in the future. It is suggested that a combination of fission reactors with technologies unavailable in the 1950's, when the design characteristics of the current nuclear power plants were established, could be considered to overcome this barrier. (author)

Small hydropower plants in the region of Mariovo (Macedonia)

International Nuclear Information System (INIS)

Panovski, Sotir; Anastasov, Ljupcho

2003-01-01

In this paper the results of an initial Pre-feasibility study within the framework of the PHARE Programme for Cross Border Cooperation between Republic of Macedonia and Republic of Greece. In this study we have looked at the existing research originating from three sources. The Strategies for Economic Development of Republic of Macedonia, the Development Plans of the Electric Power Company of Macedonia as well as the existing technical documentation and studies on a level of idea projects for specific location for small hydropower plants in Mariovo region. Furthermore, analysis and evaluation of this documentation is included. Research done in this region has produced evidence of numerous potential locations for small hydropower plants (total of 46) generating power between 58 kW and 4900 kW, discharging between 0,082 m 3 /s and 30 m 3 /s with a head between 6 m and 208 m for which we have detailed data. Furthermore, in the paper we pay attention to the enormous and so far unrealised hydro energetic power which could be utilised by constructing small hydropower plants in Republic of Macedonia. specifically in the Mariovo region. (Original)

Seeing the forest for the trees: annotating small RNA producing genes in plants.

Science.gov (United States)

Coruh, Ceyda; Shahid, Saima; Axtell, Michael J

2014-04-01

A key goal in genomics is the complete annotation of the expressed regions of the genome. In plants, substantial portions of the genome make regulatory small RNAs produced by Dicer-Like (DCL) proteins and utilized by Argonaute (AGO) proteins. These include miRNAs and various types of endogenous siRNAs. Small RNA-seq, enabled by cheap and fast DNA sequencing, has produced an enormous volume of data on plant miRNA and siRNA expression in recent years. In this review, we discuss recent progress in using small RNA-seq data to produce stable and reliable annotations of miRNA and siRNA genes in plants. In addition, we highlight key goals for the future of small RNA gene annotation in plants. Copyright © 2014 Elsevier Ltd. All rights reserved.

Villacidro solar demo plant: Integration of small-scale CSP and biogas power plants in an industrial microgrid

Science.gov (United States)

Camerada, M.; Cau, G.; Cocco, D.; Damiano, A.; Demontis, V.; Melis, T.; Musio, M.

2016-05-01

The integration of small scale concentrating solar power (CSP) in an industrial district, in order to develop a microgrid fully supplied by renewable energy sources, is presented in this paper. The plant aims to assess in real operating conditions, the performance, the effectiveness and the reliability of small-scale concentrating solar power technologies in the field of distributed generation. In particular, the potentiality of small scale CSP with thermal storage to supply dispatchable electricity to an industrial microgrid will be investigated. The microgrid will be realized in the municipal waste treatment plant of the Industrial Consortium of Villacidro, in southern Sardinia (Italy), which already includes a biogas power plant. In order to achieve the microgrid instantaneous energy balance, the analysis of the time evolution of the waste treatment plant demand and of the generation in the existing power systems has been carried out. This has allowed the design of a suitable CSP plant with thermal storage and an electrochemical storage system for supporting the proposed microgrid. At the aim of obtaining the expected energy autonomy, a specific Energy Management Strategy, which takes into account the different dynamic performances and characteristics of the demand and the generation, has been designed. In this paper, the configuration of the proposed small scale concentrating solar power (CSP) and of its thermal energy storage, based on thermocline principle, is initially described. Finally, a simulation study of the entire power system, imposing scheduled profiles based on weather forecasts, is presented.

A Comparison of Prediction Methods for Design of Pump as Turbine for Small Hydro Plant: Implemented Plant

Science.gov (United States)

Naeimi, Hossein; Nayebi Shahabi, Mina; Mohammadi, Sohrab

2017-08-01

In developing countries, small and micro hydropower plants are very effective source for electricity generation with energy pay-back time (EPBT) less than other conventional electricity generation systems. Using pump as turbine (PAT) is an attractive, significant and cost-effective alternative. Pump manufacturers do not normally provide the characteristic curves of their pumps working as turbines. Therefore, choosing an appropriate Pump to work as a turbine is essential in implementing the small-hydro plants. In this paper, in order to find the best fitting method to choose a PAT, the results of a small-hydro plant implemented on the by-pass of a Pressure Reducing Valve (PRV) in Urmia city in Iran are presented. Some of the prediction methods of Best Efficiency Point of PATs are derived. Then, the results of implemented project have been compared to the prediction methods results and the deviation of from measured data were considered and discussed and the best method that predicts the specifications of PAT more accurately determined. Finally, the energy pay-back time for the plant is calculated.

Nucleic acids encoding phloem small RNA-binding proteins and transgenic plants comprising them

Science.gov (United States)

Lucas, William J.; Yoo, Byung-Chun; Lough, Tony J.; Varkonyi-Gasic, Erika

2007-03-13

The present invention provides a polynucleotide sequence encoding a component of the protein machinery involved in small RNA trafficking, Cucurbita maxima phloem small RNA-binding protein (CmPSRB 1), and the corresponding polypeptide sequence. The invention also provides genetic constructs and transgenic plants comprising the polynucleotide sequence encoding a phloem small RNA-binding protein to alter (e.g., prevent, reduce or elevate) non-cell autonomous signaling events in the plants involving small RNA metabolism. These signaling events are involved in a broad spectrum of plant physiological and biochemical processes, including, for example, systemic resistance to pathogens, responses to environmental stresses, e.g., heat, drought, salinity, and systemic gene silencing (e.g., viral infections).

Small Nuclear Co-generation Plants Based on Shipbuilding Technology

International Nuclear Information System (INIS)

Vasyukov, V. I.; Veshnyakov, K. B.; Goryunov, E. V.; Zalugin, V. I.; Panov, Yu. K.; Polunichev, V. I.

2002-01-01

The development of nuclear cogeneration plants and power desalination complexes of relatively small power, using proven shipbuilding technology, becomes more and more attractive for solving the power supply problems of remote districts of the Extreme North and the Far East with small and medium power grids and for removing the shortage of fresh water in different world regions. The idea of transportation of the power unit with high degree of readiness to the place of its location with minimum construction and mounting activities at the site is very attractive. Compactness typical of RP based on shipbuilding technology allows to develop floating or ground-based plants at minimum use of water area and territory. Small construction scope at the site under conditions of minimum anthropogenic loads and high ecological indices are important arguments in favor of floating nuclear cogeneration plant based on ship power units against the alternative fossil sources. At present, the activities on floating nuclear cogeneration plant design, which is developed on the basis of floating power unit with two KLT-40S reactor plant, which is a modified option of standard KLT-40-type ship plant for icebreaker fleet in Russia are the most advanced. To date, a detailed design of reactor plant has been developed and approved, design activities on floating power unit are in the stage of completion, the site for its location has been selected and licensing by GAN, Russia, is in progress. Besides OKBM has developed some designs of nuclear cogeneration plants of different power on the basis of integral reactor plants, using the experience of transport and stationary power plants designing. Nuclear cogeneration plant investment analysis showed acceptable social and economical efficiency of the design that creates conditions for commercial construction of floating power units with KLT-40S reactor plan. At the same time the reduction of the design recovering terms, increase of budget income and

High-Level Accumulation of Exogenous Small RNAs Not Affecting Endogenous Small RNA Biogenesis and Function in Plants

Institute of Scientific and Technical Information of China (English)

SHEN Wan-xia; Neil A Smith; ZHOU Chang-yong; WANG Ming-bo

2014-01-01

RNA silencing is a fundamental plant defence and gene control mechanism in plants that are directed by 20-24 nucleotide (nt) small interfering RNA (siRNA) and microRNA (miRNA). Infection of plants with viral pathogens or transformation of plants with RNA interference (RNAi) constructs is usually associated with high levels of exogenous siRNAs, but it is unclear if these siRNAs interfere with endogenous small RNA pathways and hence affect plant development. Here we provide evidence that viral satellite RNA (satRNA) infection does not affect siRNA and miRNA biogenesis or plant growth despite the extremely high level of satRNA-derived siRNAs. We generated transgenic Nicotiana benthamiana plants that no longer develop the speciifc yellowing symptoms generally associated with infection by Cucumber mosaic virus (CMV) Y-satellite RNA (Y-Sat). We then used these plants to show that CMV Y-Sat infection did not cause any visible phenotypic changes in comparison to uninfected plants, despite the presence of high-level Y-Sat siRNAs. Furthermore, we showed that the accumulation of hairpin RNA (hpRNA)-derived siRNAs or miRNAs, and the level of siRNA-directed transgene silencing, are not signiifcantly affected by CMV Y-Sat infection. Taken together, our results suggest that the high levels of exogenous siRNAs associated with viral infection or RNAi-inducing transgenes do not saturate the endogenous RNA silencing machineries and have no signiifcant impact on normal plant development.

Financial analysis of large versus small nuclear power plants

International Nuclear Information System (INIS)

Louh, R.F.; Becker, M.; Wicks, F.

1986-01-01

There have been no new orders for nuclear plants and many nuclear plants under construction have been cancelled in recent years in the United States. Financing problems have been a major factor in this slow down of new nuclear plant activity. Meanwhile, the nuclear plants that have been completed have been operating cost effectively and yielding fossil fuel conservation and air quality benefits. Smaller plants have been designed in the past for the purpose of penetrating markets in developing countries and countries with relatively small utility systems. This paper examines the question of whether these smaller plants would be a viable option to large nuclear plants in the United States. Although the smaller plants are estimated to have a somewhat higher capital cost on a $/k W basis, they have the potential advantage of a lower total financial committment. The computational tools required for this evaluation are optimal generation planning and financial simulation programs and the corresponding generation and financial data bases for a variety of systems

Community-Weighted Mean Plant Traits Predict Small Scale Distribution of Insect Root Herbivore Abundance.

Directory of Open Access Journals (Sweden)

Ilja Sonnemann

Full Text Available Small scale distribution of insect root herbivores may promote plant species diversity by creating patches of different herbivore pressure. However, determinants of small scale distribution of insect root herbivores, and impact of land use intensity on their small scale distribution are largely unknown. We sampled insect root herbivores and measured vegetation parameters and soil water content along transects in grasslands of different management intensity in three regions in Germany. We calculated community-weighted mean plant traits to test whether the functional plant community composition determines the small scale distribution of insect root herbivores. To analyze spatial patterns in plant species and trait composition and insect root herbivore abundance we computed Mantel correlograms. Insect root herbivores mainly comprised click beetle (Coleoptera, Elateridae larvae (43% in the investigated grasslands. Total insect root herbivore numbers were positively related to community-weighted mean traits indicating high plant growth rates and biomass (specific leaf area, reproductive- and vegetative plant height, and negatively related to plant traits indicating poor tissue quality (leaf C/N ratio. Generalist Elaterid larvae, when analyzed independently, were also positively related to high plant growth rates and furthermore to root dry mass, but were not related to tissue quality. Insect root herbivore numbers were not related to plant cover, plant species richness and soil water content. Plant species composition and to a lesser extent plant trait composition displayed spatial autocorrelation, which was not influenced by land use intensity. Insect root herbivore abundance was not spatially autocorrelated. We conclude that in semi-natural grasslands with a high share of generalist insect root herbivores, insect root herbivores affiliate with large, fast growing plants, presumably because of availability of high quantities of food. Affiliation of

Analysis of the cost for the refurbishment of small hydropower plants

International Nuclear Information System (INIS)

Ogayar, B.; Vidal, P.G.; Hernandez, J.C.

2009-01-01

In view of all the concerns associated with fossil fuels and energy demand it is appropriate to investigate the large number of abandoned small hydropower plants. In order to solve the difficulty implied, by a viability study on the refurbishment of a small hydropower plant, a series of simple equations has been developed based on the economic optimization of the different elements. These equations can also be used for completely new hydropower plants. The result of this study will allow us to obtain quite approximate costs for the refurbishment of old hydropower plants, or the construction of new ones. These data on costs will act as a reference to examine real possibilities of refurbishment through different tools of financial and economic analysis. Although the equations developed have used unitary prices referring to Spain, they will be applicable to other countries just changing those prices for those of the country, required. (author)

Molecular ecology of Listeria monocytogenes and other Listeria species in small and very small ready-to-eat meat processing plants.

Science.gov (United States)

Williams, Shanna K; Roof, Sherry; Boyle, Elizabeth A; Burson, Dennis; Thippareddi, Harshavardhan; Geornaras, Ifigenia; Sofos, John N; Wiedmann, Martin; Nightingale, Kendra

2011-01-01

A longitudinal study was conducted to track Listeria contamination patterns in ready-to-eat meats from six small or very small meat processing plants located in three states over 1 year. A total of 688 environmental sponge samples were collected from nonfood contact surfaces during bimonthly visits to each plant. Overall, L. monocytogenes was isolated from 42 (6.1%) environmental samples, and its prevalence ranged from 1.7 to 10.8% across different plants. Listeria spp., other than L. monocytogenes, were isolated from 9.5% of samples overall, with the prevalence ranging from 1.5 to 18.3% across different plants. The prevalence of L. monocytogenes correlated well with that of other Listeria spp. for some but not all plants. One L. monocytogenes isolate representing each positive sample was characterized by molecular serotyping, EcoRI ribotyping, and pulsed-field gel electrophoresis typing. Seven sample sites tested positive for L. monocytogenes on more than one occasion, and the same ribotype was detected more than once at five of these sites. Partial sigB sequencing was used to speciate other Listeria spp. isolates and assign an allelic type to each isolate. Other Listeria spp. were isolated more than once from 14 sample sites, and the same sigB allelic type was recovered at least twice from seven of these sites. One plant was colonized by an atypical hemolytic L. innocua strain. Our findings indicate that small and very small meat processing plants that produce ready-to-eat meat products are characterized by a varied prevalence of Listeria, inconsistent correlation between contamination by L. monocytogenes and other Listeria spp., and a unique Listeria molecular ecology.

Development of an improved compact package plant for small community waste-water treatment

CSIR Research Space (South Africa)

Hulsman, A

1993-01-01

Full Text Available The challenges facing the design and operation of small community wastewater treatment plants are discussed. The package plant concept is considered and the consequent development of a compact intermittently aerated activated sludge package plant...

Horizontal Transfer of Small RNAs To and From Plants

Directory of Open Access Journals (Sweden)

Lu eHan

2015-12-01

Full Text Available Genetic information is traditionally thought to be transferred from parents to offspring. However, there is evidence indicating that gene transfer can also occur from microbes to higher species, such as plants, invertebrates and vertebrates. This horizontal transfer can be carried out by small RNAs (sRNAs. sRNAs have been recently reported to move across kingdoms as mobile signals, spreading silencing information toward targeted genes. sRNAs, especially microRNAs (miRNAs and small interfering RNAs (siRNAs, are non-coding molecules that control gene expression at the transcriptional or post-transcriptional level. Some sRNAs act in a cross-kingdom manner between animals and their parasites, but little is known about such sRNAs associated with plants. In this report, we provide a brief introduction to miRNAs that are transferred from plants to mammals/viruses and siRNAs that are transferred from microbes to plants. Both miRNAs and siRNAs can exert corresponding functions in the target organisms. Additionally, we provide information concerning a host-induced gene silencing (HIGS system as a potential application that utilizes the transgenic trafficking of RNA molecules to silence the genes of interacting organisms. Moreover, we lay out the controversial views regarding cross-kingdom miRNAs and call for better methodology and experimental design to confirm this unique function of miRNAs.

How to conserve threatened Chinese plant species with extremely small populations?

Directory of Open Access Journals (Sweden)

Sergei Volis

2016-02-01

Full Text Available The Chinese flora occupies a unique position in global plant diversity, but is severely threatened. Although biodiversity conservation in China has made significant progress over the past decades, many wild plant species have extremely small population sizes and therefore are in extreme danger of extinction. The concept of plant species with extremely small populations (PSESPs, recently adopted and widely accepted in China, lacks a detailed description of the methodology appropriate for conserving PSESPs. Strategies for seed sampling, reintroduction, protecting PSESP locations, managing interactions with the local human population, and other conservation aspects can substantially differ from those commonly applied to non-PSESPs. The present review is an attempt to provide a detailed conservation methodology with realistic and easy-to-follow guidelines for PSESPs in China.

Small manufacturing plants, pollution, and poverty : new evidence from Brazil and Mexico

OpenAIRE

Dasgupta, Susmita; Lucas, Robert E. B.; Wheeler, David

1998-01-01

The authors use new data from Brazil and Mexico to analyze relationships linking economic development, the size distribution of manufacturing plants, and exposure to industrial pollution. For lack of data, prior work in this field has been limited largely to water pollution and medium-size plants. This study examines air pollution and encompasses small plants (with 1 to 20 employees) as well as medium-size and large plants. Four main questions are addressed (with answers from plant-level data...

Plant Responses to Pathogen Attack: Small RNAs in Focus.

Science.gov (United States)

Islam, Waqar; Noman, Ali; Qasim, Muhammad; Wang, Liande

2018-02-08

Small RNAs (sRNA) are a significant group of gene expression regulators for multiple biological processes in eukaryotes. In plants, many sRNA silencing pathways produce extensive array of sRNAs with specialized roles. The evidence on record advocates for the functions of sRNAs during plant microbe interactions. Host sRNAs are reckoned as mandatory elements of plant defense. sRNAs involved in plant defense processes via different pathways include both short interfering RNA (siRNA) and microRNA (miRNA) that actively regulate immunity in response to pathogenic attack via tackling pathogen-associated molecular patterns (PAMPs) and other effectors. In response to pathogen attack, plants protect themselves with the help of sRNA-dependent immune systems. That sRNA-mediated plant defense responses play a role during infections is an established fact. However, the regulations of several sRNAs still need extensive research. In this review, we discussed the topical advancements and findings relevant to pathogen attack and plant defense mediated by sRNAs. We attempted to point out diverse sRNAs as key defenders in plant systems. It is hoped that sRNAs would be exploited as a mainstream player to achieve food security by tackling different plant diseases.

A new small HTGR power plant concept with inherently safe features--An engineering and economic challenge

International Nuclear Information System (INIS)

McDonald, C.F.; Sonn, D.L.

1983-01-01

This paper outlines a small nuclear plant concept which is not meant to replace the large nuclear power plants that will continue to be needed by the industrialized nations, but rather recognizes the needs of the smaller energy user, both for special applications in the US and for the developing nations. The small High-Temperature Gas-Cooled Reactor (HTGR), whose introduction will be very dependent on market forces, represents only one approach to meet these needs. The design of a small power plant that could be inherently safer and that might have costs less than those indicated by the traditional reverse-economy-of-scale effect is discussed. Topics considered include power plant economics, the small steam cycle HTGR thermodynamic cycle, the reactor nuclear heat source layout, the reactor heat removal system (main loop cooling, a vessel cooling system with reactor pressurized, vessel cooling system with reactor depressurized), safety considerations, investment risk protection, the technology base, and applications for the small HTGR plant concept

Co-generation and innovative heat storage systems in small-medium CSP plants for distributed energy production

Science.gov (United States)

Giaconia, Alberto; Montagnino, Fabio; Paredes, Filippo; Donato, Filippo; Caputo, Giampaolo; Mazzei, Domenico

2017-06-01

CSP technologies can be applied for distributed energy production, on small-medium plants (on the 1 MW scale), to satisfy the needs of local communities, buildings and districts. In this perspective, reliable, low-cost, and flexible small/medium multi-generative CSP plants should be developed. Four pilot plants have been built in four Mediterranean countries (Cyprus, Egypt, Jordan, and Italy) to demonstrate the approach. In this paper, the plant built in Italy is presented, with specific innovations applied in the linear Fresnel collector design and the Thermal Energy Storage (TES) system, based on a single the use of molten salts but specifically tailored for small scale plants.

Small unmanned aerial vehicles (micro-UAVs, drones) in plant ecology.

Science.gov (United States)

Cruzan, Mitchell B; Weinstein, Ben G; Grasty, Monica R; Kohrn, Brendan F; Hendrickson, Elizabeth C; Arredondo, Tina M; Thompson, Pamela G

2016-09-01

Low-elevation surveys with small aerial drones (micro-unmanned aerial vehicles [UAVs]) may be used for a wide variety of applications in plant ecology, including mapping vegetation over small- to medium-sized regions. We provide an overview of methods and procedures for conducting surveys and illustrate some of these applications. Aerial images were obtained by flying a small drone along transects over the area of interest. Images were used to create a composite image (orthomosaic) and a digital surface model (DSM). Vegetation classification was conducted manually and using an automated routine. Coverage of an individual species was estimated from aerial images. We created a vegetation map for the entire region from the orthomosaic and DSM, and mapped the density of one species. Comparison of our manual and automated habitat classification confirmed that our mapping methods were accurate. A species with high contrast to the background matrix allowed adequate estimate of its coverage. The example surveys demonstrate that small aerial drones are capable of gathering large amounts of information on the distribution of vegetation and individual species with minimal impact to sensitive habitats. Low-elevation aerial surveys have potential for a wide range of applications in plant ecology.

Energy audit in small wastewater treatment plants: methodology, energy consumption indicators, and lessons learned.

Science.gov (United States)

Foladori, P; Vaccari, M; Vitali, F

2015-01-01

Energy audits in wastewater treatment plants (WWTPs) reveal large differences in the energy consumption in the various stages, depending also on the indicators used in the audits. This work is aimed at formulating a suitable methodology to perform audits in WWTPs and identifying the most suitable key energy consumption indicators for comparison among different plants and benchmarking. Hydraulic-based stages, stages based on chemical oxygen demand, sludge-based stages and building stages were distinguished in WWTPs and analysed with different energy indicators. Detailed energy audits were carried out on five small WWTPs treating less than 10,000 population equivalent and using continuous data for 2 years. The plants have in common a low designed capacity utilization (52% on average) and equipment oversizing which leads to waste of energy in the absence of controls and inverters (a common situation in small plants). The study confirms that there are several opportunities for reducing energy consumption in small WWTPs: in addition to the pumping of influent wastewater and aeration, small plants demonstrate low energy efficiency in recirculation of settled sludge and in aerobic stabilization. Denitrification above 75% is ensured through intermittent aeration and without recirculation of mixed liquor. Automation in place of manual controls is mandatory in illumination and electrical heating.

Optimal designs of small CHP plants in a market with fluctuating electricity prices

DEFF Research Database (Denmark)

Lund, Henrik; Andersen, A.N.

2005-01-01

The paper presents the Danish experince with methodologies and software tools, which have been used to design investment and operation strategies for almost all small CHP plants in Denmark during the decade of the triple tariff.......The paper presents the Danish experince with methodologies and software tools, which have been used to design investment and operation strategies for almost all small CHP plants in Denmark during the decade of the triple tariff....

Comparative phylogenetic and expression analysis of small GTPases families in legume and non-legume plants.

Science.gov (United States)

Flores, Ana Claudia; Via, Virginia Dalla; Savy, Virginia; Villagra, Ulises Mancini; Zanetti, María Eugenia; Blanco, Flavio

2018-02-01

Small monomeric GTPases act as molecular switches in several processes that involve polar cell growth, participating mainly in vesicle trafficking and cytoskeleton rearrangements. This gene superfamily has largely expanded in plants through evolution as compared with other Kingdoms, leading to the suggestion that members of each subfamily might have acquired new functions associated to plant-specific processes. Legume plants engage in a nitrogen-fixing symbiotic interaction with rhizobia in a process that involves polar growth processes associated with the infection throughout the root hair. To get insight into the evolution of small GTPases associated with this process, we use a comparative genomic approach to establish differences in the Ras GTPase superfamily between legume and non-legume plants. Phylogenetic analyses did not show clear differences in the organization of the different subfamilies of small GTPases between plants that engage or not in nodule symbiosis. Protein alignments revealed a strong conservation at the sequence level of small GTPases previously linked to nodulation by functional genetics. Interestingly, one Rab and three Rop proteins showed conserved amino acid substitutions in legumes, but these changes do not alter the predicted conformational structure of these proteins. Although the steady-state levels of most small GTPases do not change in response to rhizobia, we identified a subset of Rab, Rop and Arf genes whose transcript levels are modulated during the symbiotic interaction, including their spatial distribution along the indeterminate nodule. This study provides a comprehensive study of the small GTPase superfamily in several plant species. The genetic program associated to root nodule symbiosis includes small GTPases to fulfill specific functions during infection and formation of the symbiosomes. These GTPases seems to have been recruited from members that were already present in common ancestors with plants as distant as monocots

Antibiotics impact plant traits, even at small concentrations

Science.gov (United States)

Deloy, Andrea; Volkert, Anna Martina; Leonhardt, Sara Diana; Pufal, Gesine

2017-01-01

Abstract Antibiotics of veterinary origin are released to agricultural fields via grazing animals or manure. Possible effects on human health through the consumption of antibiotic exposed crop plants have been intensively investigated. However, information is still lacking on the effects of antibiotics on plants themselves, particularly on non-crop species, although evidence suggests adverse effects of antibiotics on growth and performance of plants. This study evaluated the effects of three major antibiotics, penicillin, sulfadiazine and tetracycline, on the germination rates and post-germinative traits of four plant species during ontogenesis and at the time of full development. Antibiotic concentrations were chosen as to reflect in vivo situations, i.e. concentrations similar to those detected in soils. Plant species included two herb species and two grass species, and represent two crop-species and two non-crop species commonly found in field margins, respectively. Germination tests were performed in climate chambers and effects on the remaining plant traits were determined in greenhouse experiments. Results show that antibiotics, even in small concentrations, significantly affect plant traits. These effects include delayed germination and post-germinative development. Effects were species and functional group dependent, with herbs being more sensitive to antibiotics then grasses. Responses were either negative or positive, depending on plant species and antibiotic. Effects were generally stronger for penicillin and sulfadiazine than for tetracycline. Our study shows that cropland species respond to the use of different antibiotics in livestock industry, for example, with delayed germination and lower biomass allocation, indicating possible effects on yield in farmland fertilized with manure containing antibiotics. Also, antibiotics can alter the composition of plant species in natural field margins, due to different species-specific responses, with unknown

The application of the EMAS-ordinance to small hydro-power-plants

International Nuclear Information System (INIS)

Patek, R.

2000-01-01

The application of the eco-management and audit scheme ordinance to small hydro-power-plants deals with the possibility to take an environmental-relevant audition on sites of small hydro-power-plants to achieve the environmental EMAS-certificate. Within the realization of the acquired improvement steps also the efficiency of the power plants should be increased that the audit also becomes interesting in economic matters. Contents: after explaining the legal frame being prescribed by the European Community, its interpretation and relevance for the sites of SHP, common impacts of these on the environment are particularized. From these facts a valuation-catalogue has been developed, which will be used by the power plant-owners for the assessment of their sites to take part in the EMAS-system. This catalogue is split up into six modules, which comprise all possible valuation areas which can appear concerning the different kinds of plants. These modules are: MODUL A: backwater area; MODUL B: weir; MODUL C: powerhouse; MODUL D: tail water area; MODUL E: diversion channel / penstock; MODUL F: diversion section. Furthermore three submodules to gather common data concerning plant and river have been created. At the development of the catalogue there was particularly attached importance to a user-friendly application. The goal was to realize the valuation by the plant owners to minimize costs. To take objectiveness into account the module-catalogue was created in a way that auditors (the power plant owners) must not formulate specifications by themselves; the possible assessments only have to be marked with a cross at the corresponding parameters, which have been listed up. (author)

Design report small-scale fuel alcohol plant. Volume 2: Detailed construction information

Science.gov (United States)

1980-12-01

The objectives are to provide potential alcohol producers with a reference design and provide a complete, demonstrated design of a small scale fuel alcohol plant. The plant has the capability for feedstock preparation, cooking, saccharification, fermentation, distillation, by-product dewatering, and process steam generation. An interesting feature is an instrumentation and control system designed to allow the plant to run 24 hours per day with only four hours of operator attention.

Short-cut design of small hydroelectric plants

Energy Technology Data Exchange (ETDEWEB)

Voros, N.G.; Kiranoudis, C.T.; Maroulis, Z.B. [National Technical Univ. of Athens, Dept. of Chemical Engineering, Athens (Greece)

2000-04-01

The problem of designing small hydroelectric plants has been properly analysed and addressed in terms of maximising the economic benefits of the investment. An appropriate empirical model describing hydroturbine efficiency was developed. An overall plant model was introduced by taking into account their construction characteristics and operational performance. The hydrogeographical characteristics for a wide range of sites have been appropriately analysed and a model that involves significant physical parameters has been developed. The design problem was formulated as a mathematical programming problem, and solved using appropriate programming techniques. The optimisation covered a wide range of site characteristics and three types of commercially available hydroturbines. The methodology introduced an empirical short-cut design equation for the determination of the optimum nominal flowrate of the hydroturbines and the estimation of the expected unit cost of electricity produced, as well as of the potential amount of annually recovered energy. (Author)

A novel small dynamic solar thermal desalination plant with a fluid piston converter

International Nuclear Information System (INIS)

Mahkamov, Khamid; Orda, Eugene; Belgasim, Basim; Makhkamova, Irina

2015-01-01

Highlights: • A dynamic solar desalination plant was developed which works cyclically. • It integrates an evacuated tube solar collector and fluid piston converter. • Pressure during desalination process varies with frequency of 2–4 Hz. • The system has a small increase in fresh water yield and provides pumping capacity. • Mathematical modelling provides accurate description of experimental performance. - Abstract: An innovative small dynamic water desalination plant was developed and tested under laboratory conditions. The system is a combination of a heat pipe evacuated tube solar collector, conventional condenser and novel fluid piston converter. Saline water is boiled and turned into vapour in the manifold of the solar collector. A small fraction of the solar energy supplied to the plant is used to drive the fluid piston converter. Oscillations of the fluid piston periodically change the volume and pressure in the plant. For the duration of approximately half of the periodic cycle the pressure in the plant drops below the atmospheric level causing flash boiling of saline water in the manifold of the solar collector. Generated vapour is turned into fresh water in the condenser which is surrounded by a cooling jacket with saline water. The flash boiling effect improves the fresh water production capacity of the plant. Additionally, the fluid piston converter drives a pump which provides lifting of saline water from a well and pumps this through the cooling jacket of the condenser to a saline water storage tank. This tank replenishes saline water in the manifold of the solar collector. Experimental investigations demonstrated the saline water self-circulation capability of the plant and increase in the fresh water production compared to the static mode of operation. Experimental data was also used to calibrate the mathematical model of the plant. Comparison of theoretical and experimental information demonstrates that the model accurately predicts the

Small proteins of plant-pathogenic fungi secreted during host colonization.

NARCIS (Netherlands)

Rep, M.

2005-01-01

Small proteins secreted by plant pathogenic fungi in their hosts have been implicated in disease symptom development as well as in R-gene mediated disease resistance. Characteristically, this class of proteins shows very limited phylogenetic distribution, possibly due to accelerated evolution

Conditions for new biofuel raw materials. Systems for small scale briquetting and pelletizing; Foerutsaettningar foer nya biobraensleraavaror. System foer smaaskalig brikettering och pelletering

Energy Technology Data Exchange (ETDEWEB)

Paulrud, Susanne; Holmgren, Kristina (The Swedish Environmental Research Institute Ltd., Stockholm (Sweden)); Rosenqvist, Haakan; Boerjesson, Paal (Environmental and Energy Systems Studies, Lund Inst. of Technology, Lund (Sweden))

2009-01-15

limited by the raw material's combustion characteristics. Reed canary grass has the best potential nationally to be used as a raw material in small-scale production plants. For reed canary grass, briquette production is favourable over pellet production because pellets production is more expensive, involves a more advanced process and is dependent on a small-scale household market in order to be profitable. The results show that a price difference of 90 Swedish kronor/MWh between reed canary grass in bales and briquettes is sufficient for briquette production to be more profitable than bales for larger heating plants. The production of pellets from the products of thinning and precommercial thinning in small local plants can become a viable alternative where a shortage of traditional raw materials (e.g. sawmill waste) begins to limit the supply of cheap raw materials to larger pellets production plants. However, this is dependant on the technology and methods becoming more cost effective and on the demand for refined biomass continuing to increase. One alternative is biomass polygeneration in combined heat and power plants where pellets are produced from forestry raw materials. In the introductory phase, it may be of interest to use existing technology in the form of mobile pellet plants

The Hetex small-scale hydro plant

International Nuclear Information System (INIS)

Guentert, P.; Boller, F.; Wanner, A.

2006-01-01

This final report for the Swiss Federal Office of Energy (SFOE) takes a look at the 400 kW small hydroelectric power plant (SHP) installed on the Aabach stream in Niederlenz, Switzerland. With a maximum water-flow of 4.5 m 3 /s, the turbine can produce about 1.5 GWh of electricity per year. In spring 2005, bearing damage necessitated substantial renovation to the turbine and the generator. This study examines the state of the rest of the plant noted during maintenance work. It also focuses on the feeding of the electricity produced into the grid, the effects of increased residual water-flow, the option of using the Hallwilersee lake as a buffer, upstream flood evacuation and the possibility of green electricity certification. The calculation of the amount of water available is discussed. Due to inconsistent data, a corrected flow-duration curve was used. For the local river authorities, the through passage for fish from the Aare river up to the Hallwilersee has a high priority. The Hetex SHP weir is one of nine barriers to a direct connection. The planning of a fish-pass to be built in 2006 is discussed

Small unmanned aerial vehicles (micro-UAVs, drones) in plant ecology1

Science.gov (United States)

Cruzan, Mitchell B.; Weinstein, Ben G.; Grasty, Monica R.; Kohrn, Brendan F.; Hendrickson, Elizabeth C.; Arredondo, Tina M.; Thompson, Pamela G.

2016-01-01

Premise of the study: Low-elevation surveys with small aerial drones (micro–unmanned aerial vehicles [UAVs]) may be used for a wide variety of applications in plant ecology, including mapping vegetation over small- to medium-sized regions. We provide an overview of methods and procedures for conducting surveys and illustrate some of these applications. Methods: Aerial images were obtained by flying a small drone along transects over the area of interest. Images were used to create a composite image (orthomosaic) and a digital surface model (DSM). Vegetation classification was conducted manually and using an automated routine. Coverage of an individual species was estimated from aerial images. Results: We created a vegetation map for the entire region from the orthomosaic and DSM, and mapped the density of one species. Comparison of our manual and automated habitat classification confirmed that our mapping methods were accurate. A species with high contrast to the background matrix allowed adequate estimate of its coverage. Discussion: The example surveys demonstrate that small aerial drones are capable of gathering large amounts of information on the distribution of vegetation and individual species with minimal impact to sensitive habitats. Low-elevation aerial surveys have potential for a wide range of applications in plant ecology. PMID:27672518

Analysis of near optimum design for small and medium size nuclear power plants

International Nuclear Information System (INIS)

Ahmed, A.A.

1977-01-01

Market surveys in recent years have shown that a significant market would exist among the developing nations of the world for nuclear power plants that would be classified as small to medium sized, provided that these small plants could produce electricity at a unit price comparable to that of equivalent sized fossil fired plants. Nuclear plants in the range of 100 MWe to 500 MWe would fit more effectively into the relatively smaller grids of most developing nations than would the 900 MWe to 1300 MWe units now being constructed in the large industrial nations. Worldwide re-evaluation of the worth of fossil fuels has prompted a re-examination of the competitive position of small to medium sized nuclear generating units compared to comparable fossil fired units, especially in the context of units specifically optimized for the size range of interest, rather than of designs that are simply scaled down versions of the currently available larger units. Since the absolute cost of electricity is more sensitive to external factors such as cost of money, national inflation rate and time required for licensing and construction than to details of design or perhaps even to choice of fuels, and since the cost of electricity generated in small to medium sized fossil fired units is periodically compared to that of scaled down versions of conventional large nuclear units, the point of view taken here is one of comparing the relative generating costs of smaller nuclear units of optimum design with the corresponding costs of scaled down versions of current large nuclear generating units

MOBIL CONTAINER UNIT FOR SEWAGE SLUDGE UTILIZATION FROM SMALL AND MEDIUM WASTWATER TREATMENT PLANTS

OpenAIRE

Stanisław Ledakowicz; Paweł Stolarek; A. Malinowski

2016-01-01

The most wastewater treatment plants in Poland are small and medium plants of flow capacity below 1000 m3/d. These plants are not able to build sludge incineration plants and the transportation costs to the nearest plants increase the total costs of wastewater treatment. Polish company Metal Expert together with the French company ETIA and Lodz University of Technology proposed mobile unit for integrated drying and pyrolysis of sewage sludge in a pilot bench scale with capacity of 100 kg/h ...

Creation of transgenic rice plants producing small interfering RNA of Rice tungro spherical virus.

Science.gov (United States)

Le, Dung Tien; Chu, Ha Duc; Sasaya, Takahide

2015-01-01

Rice tungro spherical virus (RTSV), also known as Rice waika virus, does not cause visible symptoms in infected rice plants. However, the virus plays a critical role in spreading Rice tungro bacilliform virus (RTBV), which is the major cause of severe symptoms of rice tungro disease. Recent studies showed that RNA interference (RNAi) can be used to develop virus-resistance transgenic rice plants. In this report, we presented simple procedures and protocols needed for the creation of transgenic rice plants capable of producing small interfering RNA specific against RTSV sequences. Notably, our study showed that 60 out of 64 individual hygromycin-resistant lines (putative transgenic lines) obtained through transformation carried transgenes designed for producing hairpin double-stranded RNA. Northern blot analyses revealed the presence of small interfering RNA of 21- to 24-mer in 46 out of 56 confirmed transgenic lines. Taken together, our study indicated that transgenic rice plants carrying an inverted repeat of 500-bp fragments encoding various proteins of RTSV can produce small interfering RNA from the hairpin RNA transcribed from that transgene. In light of recent studies with other viruses, it is possible that some of these transgenic rice lines might be resistant to RTSV.

Integral design small nuclear power plant UNITHERM

International Nuclear Information System (INIS)

Adamovich, L. A.; Grechko, G. I.; Ulasevich, V. K.; Shishkin, V. A.

1995-01-01

The need to erect expensive energy transmission lines to these places demands to use independent local energy sources. Therefore, a reasonable alternative to the plants fired fossil fuel, mostly hydrocarbon fuel, may come from the nuclear power plants (NPP) of relatively small capacity which are nonattended, shipped to the site by large-assembled modules and completely withdrawable from the site during decommissioning. Application of NPPs for power and heat supply may prove to be cost-efficient and rather positive from social and ecological point of view. UNITHERM NPP belongs to such energy sources and may be used for heat and power supply. Heat can be provided both as hot water and superheated steam. The consumers are able to specify heat/energy supply ratio. NPP design provides for independent energy supply to the consumers and the possibility to disconnect each of them without disruption of operation of the others. Thermal hydraulic diagram of UNITHERM NPP provides for the use of three interconnected, process circuits. The consumers of thermal energy (turbogenerator unit and boilers of the central heating unit) are arranged in the last circuit

Small RNAs in plants: Recent development and application for crop improvement

Directory of Open Access Journals (Sweden)

Ayushi eKamthan

2015-04-01

Full Text Available The phenomenon of RNA interference (RNAi which involves sequence specific gene regulation by small non-coding RNAs i.e small interfering RNA (siRNA and micro RNA (miRNA has emerged as one of most powerful approaches for crop improvement. RNAi based on siRNA is one of the widely used tools of reverse genetics which aid in revealing gene functions in many species. This technology has been extensively applied to alter the gene expression in plants with an aim to achieve desirable traits. RNAi has been used for enhancing the crop yield and productivity by manipulating the gene involved in biomass, grain yield and enhanced shelf life of fruits & vegetables. It has also been applied for developing resistance against various biotic (bacteria, fungi, viruses, nematodes, insects and abiotic stresses (drought, salinity, cold etc.. Nutritional improvements of crops have also been achieved by enriching the crops with essential amino acids, fatty acids, antioxidants and other nutrients beneficial for human health or by reducing allergens or anti-nutrients. Micro RNAs are key regulators of important plant processes like growth, development and response to various stresses. In spite of similarity in size (20-24nt, miRNA differ from siRNA in precursor structures, pathway of biogenesis, and modes of action. This review also highlights the miRNA based genetic modification technology where various miRNAs/artificial miRNAs and their targets can be utilized for improving several desirable plant traits. Micro RNA based strategies are much efficient than siRNA-based RNAi strategies due to its specificity and less undesirable off target effects. As per the FDA guidelines, small RNA based transgenics are much safer for consumption than those over expressing proteins. This review thereby summarizes the emerging advances and achievement in the field of small RNAs and its application for crop improvement.

Estimation of small-scale hydroelectric power plant costs; Estimacao de custos de PCH

Energy Technology Data Exchange (ETDEWEB)

Santos, Afonso Henriques Moreira [MS Consultoria Ltda, Itajuba, MG (Brazil); Universidade Federal de Itajuba (UNIFEI), MG (Brazil); Silva, Benedito Claudio da [IX Consultoria e Representacoes Ltda, Itajuba, MG (Brazil); Universidade Federal de Itajuba (UNIFEI), MG (Brazil); Magalhaes, Ricardo Nogueira [IX Consultoria e Representacoes Ltda, Itajuba, MG (Brazil)

2010-07-01

Changes in Brazilian energy scenario through last years such as increase of demand and search for clean and economically feasible renewable energy sources, has stimulated investors to small hydro power plants (SHP) sector. Such characteristics together with several economic incentives, legal and regulatory mechanisms also, have helped and stimulated building of new plants of this kind and have attracted a great number of investors to this sector. Study of costs analysis and feasibility of investments is a study which has been used since long time in SHP business market as several preliminary studies previous to civil project have significant costs which lead us to count with a feasibility analysis from the very beginning of studies, exactly what is suggested in the present methodology. Such feasibility analysis, in the common patterns where basic unit costs of each input remain outstanding, would be very complex due to great difficulty in obtaining information at initial phase of project. In this direction this study brings a contribution for investors as well as for designers of small hydro power plants since it outlines a link between physical and energetic characteristics of small hydro power plant in its total cost. Such link is based in available physical characteristics in initial phase of the project, making possible a previous comparison between arrangements of a central or even the comparison of return of investment between different plants. The resulting benefit being the possibility of choosing centrals with greater economic feasibility disregarding bad undertakings or arrangements with more expressive cost. Final result gives a better delay in return of investment, helps in power, arrangements more optimized and in saving time as well, reducing costs of undertakings. Due to large number of SHP arrangements, we chose for this study the most common in Brazil, plant of medium and large fall, shunting line balance chimney and low pressure conduit. (author)

Comparison of radionuclide levels in soil, sagebrush, plant litter, cryptogams, and small mammals

International Nuclear Information System (INIS)

Landeen, D.S.

1994-09-01

Soil, sagebrush, plant litter, cryptogam, and small mammal samples were collected and analyzed for cesium-137, strontium-90, plutonium-238, plutonium 239/240, technetium-99, and iodine-129 from 1981 to 1986 at the US Department of Energy Hanford Site in southeastern Washington State as part of site characterization and environmental monitoring activities. Samples were collected on the 200 Areas Plateau, downwind from ongoing waste management activities. Plant litter, cryptogams, and small mammals are media that are not routinely utilized in monitoring or characterization efforts for determination of radionuclide concentrations. Studies at Hanford, other US Department of Energy sites, and in eastern Europe have indicated that plant litter and cryptogams may serve as effective ''natural'' monitors of air quality. Plant litter in this study consists of fallen leaves from sagebrush and ''cryptogams'' describes that portion of the soil crust composed of mosses, lichens, algae, and fungi. Comparisons of cesium-137 and strontium-90 concentrations in the soil, sagebrush, litter, and cryptogams revealed significantly higher (p<0.05) levels in plant litter and cryptogams. Technetium-99 values were the highest in sagebrush and litter. Plutonium-238 and 239/40 and iodine-129 concentrations never exceeded 0.8 pCi/gm in all media. No evidence of any significant amounts of any radionuclides being incorporated into the small mammal community was discovered. The data indicate that plant litter and cryptogams may be better, indicators of environmental quality than soil or vegetation samples. Augmenting a monitoring program with samples of litter and cryptogams may provide a more accurate representation of radionuclide environmental uptake and/or contamination levels in surrounding ecosystems. The results of this study may be applied directly to other radioecological monitoring conducted at other nuclear sites and to the monitoring of other pollutants

Amplification of Marzagao small scale hydroelectric power plant; Ampliacao da PCH de Marzagao

Energy Technology Data Exchange (ETDEWEB)

Zeller, A.R.; Porto, D.S.; Pinto, F.S. [Leme Engenharia, MG (Brazil); Melo, A.U.; Almeida, A.M.; Pereira, D.R. [Fertiligas Industria e Comercio Ltda., MG (Brazil)

1991-12-31

This work presents the modernization and power augmentation of Marzagao small scale hydroelectric power plant. In order that the costs of the project be compatible to the total of investments in the project, it was necessary the adoption of methodologies and time scales different from those used for large and medium scale hydroelectric power plants 5 figs.

Small RNAs in plants: Recent development and application for crop improvement

OpenAIRE

Ayushi eKamthan; Abira eChaudhuri; Mohan eKamthan; Asis eDatta

2015-01-01

The phenomenon of RNA interference (RNAi) which involves sequence-specific gene regulation by small non-coding RNAs, i.e., small interfering RNA (siRNA) and microRNA (miRNA) has emerged as one of most powerful approaches for crop improvement. RNAi based on siRNA is one of the widely used tools of reverse genetics which aid in revealing gene functions in many species. This technology has been extensively applied to alter the gene expression in plants with an aim to achieve desirable traits. RN...

The origin and effect of small RNA signaling in plants

Directory of Open Access Journals (Sweden)

Jean-Sébastien eParent

2012-08-01

Full Text Available Given their sessile condition, land plants need to integrate environmental cues rapidly and send signal throughout the organism to modify their metabolism accordingly. Small RNA (sRNA molecules are among the messengers that plant cells use to carry such signals. These molecules originate from fold-back stem-loops transcribed from endogenous loci or from perfect double-stranded RNA produced through the action of RNA-dependent RNA polymerases. Once produced, sRNAs associate with Argonaute and other proteins to form the RNA-induced silencing complex (RISC that executes silencing of complementary RNA molecules. Depending on the nature of the RNA target and the Argonaute protein involved, RISC triggers either DNA methylation and chromatin modification (leading to transcriptional gene silencing, TGS or RNA cleavage or translational inhibition (leading to post-transcriptional gene silencing, PTGS. In some cases, sRNAs move to neighboring cells and/or to the vascular tissues for long-distance trafficking. Many genes are involved in the biogenesis of sRNAs and recent studies have shown that both their origin and their protein partners have great influence on their activity and range. Here we summarize the work done to uncover the mode of action of the different classes of small RNA with special emphasis on their movement and how plants can take advantage of their mobility. We also review the various genetic requirements needed for production, movement and perception of the silencing signal.

Development, modelling and evaluation of a small-scale gas liquefaction plant

DEFF Research Database (Denmark)

Nguyen, Tuong-Van; Rothuizen, Erasmus Damgaard; Markussen, Wiebke Brix

2017-01-01

A small-scale gas liquefaction plant was developed and analysed based on process simulation tools and pilot tests. It will be installed in harbours, easing the penetration of liquefied natural gas (LNG) as a maritime fuel, in a sector facing more stringent environmental regulations. The proposed...... plant uses a multi-component refrigerant together with a propane precooling cycle and plate heat exchangers, to achieve a higher performance. This LNG production concept was modelled based on the Danish natural gas composition. Firstly, the total power consumption and heat transfer conductance were...... minimised by optimising the operating conditions and the refrigerant composition. The effects of varying feed and refrigerant compositions were analysed. Secondly, the system layouts were evaluated by conducting an exergetic assessment. Finally, the most promising layouts were validated by pilot plant...

A study of a small nuclear power plant system for district heating

International Nuclear Information System (INIS)

Imamura, Mitsuru; Sato, Kotaro; Narabayashi, Tadashi; Shimazu, Yoichiro; Tsuji, Masashi

2008-01-01

We have studied nuclear power plant for district heating. Already some towns and villages in Hokkaido have requested small reactor for district heating. Using existing technology allows us to shorten development period and to keep a lid on development cost. We decided to develop new reactor based on 'MUTSU' reactor technology. 'MUTSU' had already proved its safety. And 'MUTSU' reactor was boron free reactor. It allows plant system to become more compact and simple. And load following capability by core reactivity become bigger. It means to reduce control rod movement. It leads to dependability enhancement. We calculated burn-up calculation of erbium addition fuel. In the result the core life became about 10 years. In the district heating system, there are not only district heating but also snow melting with warm water. It uses steam condenser's heat, which are only discharged now. This small plant has passive safety system. It is natural cooling of containment vessel. In case of loss of coolant accident, decay heat can remove by natural convection air cooling after 6 hours. Decay heat within 6 hours can remove by evaporative heat transfer of pool on containment vessel. (author)

The Concept of the Use of the Marine Reactor Plant in Small Electric Grids

International Nuclear Information System (INIS)

Khlopkin, N.; Makarov, V.; Pologikh, B.

2002-01-01

In report some aspects of the using marine nuclear reactor are considered for provision of need small non-interconnected power systems, as well as separate settlements and the mining enterprises disposed in regions with a undeveloped infrastructure. Recently for these purposes it is offered to use the nuclear small modular power plants. The required plant power for small electric grids lies within from 1 to several tens of MWe. Module can be collected and tested on machine-building plant, and then delivered in ready type to the working place on some transport, for instance, a barge. Through determined time it's possible to transport a module to the repair shop and also to the point of storage after the end of operation. Marine nuclear reactors on their powers, compactness, mass and size are ideal prototypes for creation of such modules. For instance, building at present floating power unit, intended for functioning in region of the Russian North, based on using reactor plants of nuclear icebreakers. Reliability and safety of the ship reactor are confirmed by their trouble-free operation during approximately 180 reactors-years. Unlike big stationary nuclear plant, working in base mode, power unit with marine reactor wholly capable to work in mode of the loading following. In contrast with reactor of nuclear icebreaker, advisable to increase the core lifetime and to reduce the enrichment of the uranium. This requires more uranium capacity fuel compositions and design of the core. In particular, possible transition from traditional for ship reactor of the channel core to cassette design. Other directions of evolution of the ship reactors, not touching the basic constructive decisions verified by practice, but promoting development of properties of self-security of plant are possible. Among such directions is reduction volumetric power density of a core. (author)

Recycling domains in plant cell morphogenesis: small GTPase effectors, plasma membrane signalling and the exocyst.

Science.gov (United States)

Zárský, Viktor; Potocký, Martin

2010-04-01

The Rho/Rop small GTPase regulatory module is central for initiating exocytotically ACDs (active cortical domains) in plant cell cortex, and a growing array of Rop regulators and effectors are being discovered in plants. Structural membrane phospholipids are important constituents of cells as well as signals, and phospholipid-modifying enzymes are well known effectors of small GTPases. We have shown that PLDs (phospholipases D) and their product, PA (phosphatidic acid), belong to the regulators of the secretory pathway in plants. We have also shown that specific NOXs (NADPH oxidases) producing ROS (reactive oxygen species) are involved in cell growth as exemplified by pollen tubes and root hairs. Most plant cells exhibit several distinct plasma membrane domains (ACDs), established and maintained by endocytosis/exocytosis-driven membrane protein recycling. We proposed recently the concept of a 'recycling domain' (RD), uniting the ACD and the connected endosomal recycling compartment (endosome), as a dynamic spatiotemporal entity. We have described a putative GTPase-effector complex exocyst involved in exocytic vesicle tethering in plants. Owing to the multiplicity of its Exo70 subunits, this complex, along with many RabA GTPases (putative recycling endosome organizers), may belong to core regulators of RD organization in plants.

Investigation of small scale sphere-pac fuel fabrication plant with external gelation process

International Nuclear Information System (INIS)

Maekawa, Kazuhiko; Yoshimura, Tadahiro; Kikuchi, Toshiaki; Hoshino, Yasushi; Munekata, Hideki; Shimizu, Makoto

2005-02-01

In feasibility studies on commercialized FBR cycle system, comprehensive system investigation and properties evaluation for candidate FBR cycle systems have been implemented through view point of safety, economics, environmental burden reduction, non-proliferation resistivity, etc. As part of these studies, an investigation of small scale sphere-pac fuel fabrication plant with external gelation process was conducted. Until last fiscal year, equipment layout in cells and overall layout design of the 200t-HM/y scale fuel fabrication plant were conducted as well as schematical design studies on main equipments in gelation and reagent recovery processes of the plant. System property data concerning economics and environmental burden reduction of fuel fabrication plant was also acquired. In this fiscal year, the processes from vibropacking to fuel assemblies storage were added to the investigation range, and a conceptual design of whole fuel fabrication plant was studied as well as deepening the design study on main equipments. The conceptual design study was mainly conducted for small 50t-HM/y scale plant and a revising investigation was done for 200t-HM/y scale plant. Taking the planed comparative evaluation with pellet fuel fabrication system into account, design of equipments which should be equivalent with pellet system, especially in post-vibropacking processes, were standardized in each system. Based on these design studies, system properties data concerning economics and environmental burden reduction of the plant was also acquired. In comparison with existing design, the cell height was lowered on condition that plug type pneumatic system was adopted and fuel fabrication building was downsized by applying rationalized layout design of pellet system to post-vibropacking processes. Reduction of reagent usage at gelation process and rationalization of sintering and O/M controlling processes etc., are foremost tasks. (author)

MOBIL CONTAINER UNIT FOR SEWAGE SLUDGE UTILIZATION FROM SMALL AND MEDIUM WASTWATER TREATMENT PLANTS

Directory of Open Access Journals (Sweden)

Stanisław Ledakowicz

2016-06-01

Full Text Available The most wastewater treatment plants in Poland are small and medium plants of flow capacity below 1000 m3/d. These plants are not able to build sludge incineration plants and the transportation costs to the nearest plants increase the total costs of wastewater treatment. Polish company Metal Expert together with the French company ETIA and Lodz University of Technology proposed mobile unit for integrated drying and pyrolysis of sewage sludge in a pilot bench scale with capacity of 100 kg/h of dewatered sludge. The pilot plant was mounted in a typical mobile container which could provide service to small and medium wastewater treatment plants offering thermal processing of sewage sludge. This unit consists of KENKI contact dryer and „Spirajoule”® pyrolyser supplied with electricity utilizing the Joule effect, and a boiler, wherein the pyrolysis gases and volatile products are burned producing steam sent to the contact dryer. The bio-char produced during sludge pyrolysis could be utilized for agriculture purposes. During preliminary experiments and short-term exploitation of the unit at Elbląg Wastewater Treatment Plant the obtained results allowed us to make a mass and energy balance depended on the process conditions in the pyrolysis temperature range of 400÷800 °C. Based on the obtained results a calculator was created in the Excel , which enables assessment of pyrolysis products content and making mass and energy balances depended on process parameters such as initial moisture of sludge, pyrolysis temperature and installation output.

Inventory studies of hydroelectric power plants: the methodological differences for small and large power plants; Estudos de inventario de usinas hidreletricas: as diferencas metodologicas para pequenas e grandes centrais

Energy Technology Data Exchange (ETDEWEB)

Bajay, Sergio Valdir [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Energia; Martinez, Carlos Barreira [Faculdade de Engenharia Civil de Itajuba, MG (Brazil)

1992-12-31

The hydroelectric potential handbook produced by ELETROBRAS provides procedures to guides the hydro power studies of river sites. In this paper, a critical analysis of these procedures is carried out, for both large and small hydro power plants, pin pointing the plant`s planning/design interface there, several proposals are put forward in the order to adapt these procedures to small hydro plants, optimizing their planning and design for the several situation, found in Brazilian reality. (author) 5 refs.

Head losses in small hydropower plant trash racks (SHP

Directory of Open Access Journals (Sweden)

N. Walczak

2016-12-01

Full Text Available Small hydropower plants (SHP are technical facilities that are part of alternative energy sources [Paish 2002]. They are primarily characterised by low unit power (in Poland below 5 MW and are often constructed on existing barrages. Electrical current produced by these plants is used to meet local demand. Considering the exploitation of SHPs, it is important to ensure a stable flow through turbines. Aggidis et al. [2010] analysed SHP equipment costs depending on the turbine set. The turbines are protected against damage with trash racks applied for capturing water-borne detritus, such as plant debris carried by water. However, trash racks as solid equipment of SHPs cause head losses, and as a consequence reduce the efficiency of the system. These losses result not only from the spacing of bars, their shape and the technical condition of the inlet chamber, but also from plant debris, its nature, and the quantity of accumulated material that effectively limits the flow. The plant debris captured on trash racks is characterised by diversity in terms of species composition related to the vegetation period and the area where hydraulic facilities are located. Therefore, it is important to maintain trash racks clean by regular removal of the accumulated material. In this context, modernised and newly built power plants are fitted with mechanical cleaners. In older facilities, manual intervention for regular cleaning is required. The present study analyses how the bar shape and the orientation angle of trash racks as well as the accumulated plant debris affect head losses. The results were obtained from laboratory tests. The research examined the impact the inclination angle of trash racks (30°, 60° and 80° has on head loss values for three different shapes of bars (cylindrical, angled and flat rectangular and various weight portions of plant debris (0.25, 0.375 and 0.5 kg. The summarised losses were determined by measuring the difference in water

Small RNAs in plants: recent development and application for crop improvement.

Science.gov (United States)

Kamthan, Ayushi; Chaudhuri, Abira; Kamthan, Mohan; Datta, Asis

2015-01-01

The phenomenon of RNA interference (RNAi) which involves sequence-specific gene regulation by small non-coding RNAs, i.e., small interfering RNA (siRNA) and microRNA (miRNA) has emerged as one of most powerful approaches for crop improvement. RNAi based on siRNA is one of the widely used tools of reverse genetics which aid in revealing gene functions in many species. This technology has been extensively applied to alter the gene expression in plants with an aim to achieve desirable traits. RNAi has been used for enhancing the crop yield and productivity by manipulating the gene involved in biomass, grain yield and enhanced shelf life of fruits and vegetables. It has also been applied for developing resistance against various biotic (bacteria, fungi, viruses, nematodes, insects) and abiotic stresses (drought, salinity, cold, etc.). Nutritional improvements of crops have also been achieved by enriching the crops with essential amino acids, fatty acids, antioxidants and other nutrients beneficial for human health or by reducing allergens or anti-nutrients. microRNAs are key regulators of important plant processes like growth, development, and response to various stresses. In spite of similarity in size (20-24 nt), miRNA differ from siRNA in precursor structures, pathway of biogenesis, and modes of action. This review also highlights the miRNA based genetic modification technology where various miRNAs/artificial miRNAs and their targets can be utilized for improving several desirable plant traits. microRNA based strategies are much efficient than siRNA-based RNAi strategies due to its specificity and less undesirable off target effects. As per the FDA guidelines, small RNA (sRNA) based transgenics are much safer for consumption than those over-expressing proteins. This review thereby summarizes the emerging advances and achievement in the field of sRNAs and its application for crop improvement.

Small punch creep test: A promising methodology for high temperature plant components life evaluation

Energy Technology Data Exchange (ETDEWEB)

Tettamanti, S [CISE SpA, Milan (Italy); Crudeli, R [ENEL SpA, Milan (Italy)

1999-12-31

CISE and ENEL are involved for years in a miniaturization creep methodology project to obtain similar non-destructive test with the same standard creep test reliability. The goal can be reached with `Small punch creep test` that collect all the requested characteristics; quasi nondestructive disk specimens extracted both on external or internal side of components, than accurately machined and tested on little and cheap apparatus. CISE has developed complete creep small punch procedure that involved peculiar test facility and correlation`s law comparable with the more diffused isostress methodology for residual life evaluation on ex-serviced high temperature plant components. The aim of this work is to obtain a simple and immediately applicable relationship useful for plant maintenance managing. More added work is need to validate the Small Punch methodology and for relationship calibration on most diffusion high temperature structural materials. First obtained results on a comparative work on ASTM A355 P12 ex-serviced pipe material are presented joint with a description of the Small Punch apparatus realized in CISE. (orig.) 6 refs.

Small punch creep test: A promising methodology for high temperature plant components life evaluation

Energy Technology Data Exchange (ETDEWEB)

Tettamanti, S. [CISE SpA, Milan (Italy); Crudeli, R. [ENEL SpA, Milan (Italy)

1998-12-31

CISE and ENEL are involved for years in a miniaturization creep methodology project to obtain similar non-destructive test with the same standard creep test reliability. The goal can be reached with `Small punch creep test` that collect all the requested characteristics; quasi nondestructive disk specimens extracted both on external or internal side of components, than accurately machined and tested on little and cheap apparatus. CISE has developed complete creep small punch procedure that involved peculiar test facility and correlation`s law comparable with the more diffused isostress methodology for residual life evaluation on ex-serviced high temperature plant components. The aim of this work is to obtain a simple and immediately applicable relationship useful for plant maintenance managing. More added work is need to validate the Small Punch methodology and for relationship calibration on most diffusion high temperature structural materials. First obtained results on a comparative work on ASTM A355 P12 ex-serviced pipe material are presented joint with a description of the Small Punch apparatus realized in CISE. (orig.) 6 refs.

Increased power to heat ratio of small scale CHP plants using biomass fuels and natural gas

International Nuclear Information System (INIS)

Savola, Tuula; Fogelholm, Carl-Johan

2006-01-01

In this paper, we present a systematic study of process changes for increased power production in 1-20 MW e combined heat and power (CHP) plants. The changes are simulated, and their economic feasibility evaluated by using existing small scale CHP case plants. Increasing power production in decentralised CHP plants that operate according to a certain heat demand could reduce the fuel consumption and CO 2 emissions per power unit produced and improve the feasibility of CHP plant investments. The CHP plant process changes were simulated under design and off design conditions and an analysis of power and heat production, investment costs and CO 2 emissions was performed over the whole annual heat demand. The results show that using biomass fuels, there are profitable possibilities to increase the current power to heat ratios, 0.23-0.48, of the small scale CHP plants up to 0.26-0.56, depending on the size of the plant. The profitable changes were a two stage district heat exchanger and the addition of a steam reheater and a feed water preheater. If natural gas is used as an additional fuel, the power to heat ratio may be increased up to 0.35-0.65 by integrating a gas engine into the process. If the CO 2 savings from the changes are also taken into account, the economic feasibility of the changes increases. The results of this work offer useful performance simulation and investment cost knowledge for the development of more efficient and economically feasible small scale CHP processes

Cost determination of the electro-mechanical equipment of a small hydro-power plant

Energy Technology Data Exchange (ETDEWEB)

Ogayar, B.; Vidal, P.G. [Grupo de Investigacion IDEA, Escuela Politecnica Superior, University of Jaen, Campus de Las Lagunillas, s/n. 23071-Jaen (Spain)

2009-01-15

One of the most important elements on the recovery of a small hydro-power plant is the electro-mechanical equipment (turbine-alternator), since the cost of the equipment means a high percentage of the total budget of the plant. The present paper intends to develop a series of equations which determine its cost from basic parameters such as power and net head. These calculations are focused at a level of previous study, so it will be necessary to carry out the engineering project and request a budget to companies specialized on the construction of electro-mechanical equipment to know its cost more accurately. Although there is a great diversity in the typology of turbines and alternators, data from manufacturers which cover all the considered range have been used. The above equations have been developed for the most common of turbines: Pelton, Francis, Kaplan and semiKaplan for a power range below 2 MW. The obtained equations have been validated with data from real installations which have been subject to analysis by engineering companies working on the assembly and design of small plants. (author)

Interactive economic analysis of small-scale heating plant

Energy Technology Data Exchange (ETDEWEB)

Landen, R.A.; Sanders, D.L.; Douglas, B.H.

1998-11-01

This report contains the work that has been undertaken by LRZ Limited in pursuance of this agreement. The potential for small-scale biomass heating systems is identified, and surrounding issues relating to acceptance are discussed. Such systems are described, and the origins of capital and running costs examined. A full review of the calculation methods for boiler plant size and fuel consumption is made, and subsequently expounded in four varying case studies. The results of this work are discussed, and the final development of the computer models is reviewed, incorporating further refinements to the method. Finally, data not contained in the text is incorporated in comprehensive appendices. (author)

Correlation between Screening estimation and noise measurement in Small Plants in Varamin city

Directory of Open Access Journals (Sweden)

S. A. R. Negahban

2013-08-01

Conclusion: No correlation was shown between the results of the two methods used. Thus, it is recommended to change the parameters used in the noise screening form for small plants, with less than 5 workers.

Conceptual design of small-sized HTGR system (4). Plant design and technical feasibility

International Nuclear Information System (INIS)

Ohashi, Hirofumi; Sato, Hiroyuki; Yan, Xing L.; Sumita, Junya; Nomoto, Yasunobu; Tazawa, Yujiro; Noguchi, Hiroki; Imai, Yoshiyuki; Tachibana, Yukio

2013-09-01

Japan Atomic Energy Agency (JAEA) has started a conceptual design of a 50MWt small-sized high temperature gas cooled reactor (HTGR) for steam supply and electricity generation (HTR50S), which is a first-of-kind of the commercial plant or a demonstration plant of a small-sized HTGR system for steam supply to the industries and district heating and electricity generation by a steam turbine, to deploy in developing countries in the 2020s. HTR50S was designed for steam supply and electricity generation by the steam turbine with the reactor outlet temperature of 750degC as a reference plant configuration. On the other hand, the intermediate heat exchanger (IHX) will be installed in the primary loop to demonstrate the electricity generation by the helium gas turbine and hydrogen production by thermochemical water splitting by utilizing the secondary helium loop with the reactor outlet temperature of 900degC as a future plant configuration. The plant design of HTR50S for the steam supply and electricity generation was performed based on the plant specification and the requirements for each system taking into account for the increase of the reactor outlet coolant temperature from 750degC to 900degC and the installation of IHX. The technical feasibility of HTR50S was confirmed because the designed systems (i.e., reactor internal components, reactor pressure vessel, vessel cooling system, shutdown cooling system, steam generator (SG), gas circulator, SG isolation and drainage system, reactor containment vessel, steam turbine and heat supply system) satisfies the design requirements. The conceptual plant layout was also determined. This paper provides the summary of the plan design and technical feasibility of HTR50S. (author)

Optimal sizing of a run-of-river small hydropower plant

International Nuclear Information System (INIS)

Anagnostopoulos, John S.; Papantonis, Dimitris E.

2007-01-01

The sizing of a small hydropower plant of the run-of-river type is very critical for the cost effectiveness of the investment. In the present work, a numerical method is used for the optimal sizing of such a plant that comprises two hydraulic turbines operating in parallel, which can be of different type and size in order to improve its efficiency. The study and analysis of the plant performance is conducted using a newly developed evaluation algorithm that simulates in detail the plant operation during the year and computes its production results and economic indices. A parametric study is performed first in order to quantify the impact of some important construction and operation factors. Next, a stochastic evolutionary algorithm is implemented for the optimization process. The examined optimization problem uses data of a specific site and is solved in the single and two-objective modes, considering, together with economic, some additional objectives, as maximization of the produced energy and the best exploitation of the water stream potential. Analyzing the results of various optimizations runs, it becomes possible to identify the most advantageous design alternatives to realize the project. It was found that the use of two turbines of different size can enhance sufficiently both the energy production of the plant and the economic results of the investment. Finally, the sensitivity of the plant performance to other external parameters can be easily studied with the present method, and some indicative results are given for different financial or hydrologic conditions

Use of medicinal plants to control Haemonchus contortus infection in small ruminants

Directory of Open Access Journals (Sweden)

Sawleha Qadir1

Full Text Available Haemonchus contortus is singly the most important of all the gastrointestinal nematodes that constrain the survival and productivity of sheep and goats owned by rural poor farmers in the developing world. This haematophagus parasite is infamous throughout the humid tropics/subtropics, being responsible for acute disease outbreaks with high levels of mortalities, particularly in young animals. Costs associated with control of this parasite in India, have been estimated to be US$ 103 million. H. contortus is also prominent amongst the reports of anthelmintic resistance that has emerged in all countries of the world that produce small ruminants. This emergence of multiple anthelmintic resistances has provided a spur for research on alternative forms of control. Recent surveys in developing countries have identified many plants that are intended and have the potential to be used as anthelmintics. This paper reviews the use of some medicinal plants as anthelmintics against H. contortus infection in small ruminants. [Veterinary World 2010; 3(11.000: 515-518

Balance of plant design issues for small reactors in Canada

International Nuclear Information System (INIS)

Harvel, G.; Meneley, D.

2014-01-01

Internationally, several companies are exploring design and development of Small Modular Reactors (SMR) ranging in power from 10 MWe to 300 MWe. While the designs are proceeding, the main issue at hand is finding a site for deployment of the first unit. Connection to existing well established grids is currently not competitive in part due to First of a Kind (FOAK) costs. As such, many vendors are exploring unique and remote applications where FOAK costs are not as significant a concern. One of the major assumptions in the design process usually followed is that the major effort needs to concentrate on reactor core development. While the reactor core is important, costs associated with the balance of plant and operations of the unit are likely to play an important role in the final decision of purchase. In this work, a series of conceptual designs is performed for the support systems of a small modular reactor by successive teams of undergraduate students working over semester long periods during a 3 year period. The goal of this process is to determine to what extent current technology for the balance of plant supports the development of a cost effective SMR. Each system is given to a team with an open set of criteria for design. At the completion of the design exercise, an open discussion with the teams is held regarding the staffing requirements for an SMR. The results are preliminary and reflect the open nature of the exercise. That said, the results indicate that for an SMR to be truly competitive, significant innovation is required in addressing the supporting systems of the plant. (author)

Balance of plant design issues for small reactors in Canada

Energy Technology Data Exchange (ETDEWEB)

Harvel, G.; Meneley, D., E-mail: Glenn.Harvel@uoit.ca, E-mail: dan.meneley@sympatico.ca [Univ. of Ontario Inst. of Tech.y, Oshawa, ON (Canada)

2014-07-01

Internationally, several companies are exploring design and development of Small Modular Reactors (SMR) ranging in power from 10 MWe to 300 MWe. While the designs are proceeding, the main issue at hand is finding a site for deployment of the first unit. Connection to existing well established grids is currently not competitive in part due to First of a Kind (FOAK) costs. As such, many vendors are exploring unique and remote applications where FOAK costs are not as significant a concern. One of the major assumptions in the design process usually followed is that the major effort needs to concentrate on reactor core development. While the reactor core is important, costs associated with the balance of plant and operations of the unit are likely to play an important role in the final decision of purchase. In this work, a series of conceptual designs is performed for the support systems of a small modular reactor by successive teams of undergraduate students working over semester long periods during a 3 year period. The goal of this process is to determine to what extent current technology for the balance of plant supports the development of a cost effective SMR. Each system is given to a team with an open set of criteria for design. At the completion of the design exercise, an open discussion with the teams is held regarding the staffing requirements for an SMR. The results are preliminary and reflect the open nature of the exercise. That said, the results indicate that for an SMR to be truly competitive, significant innovation is required in addressing the supporting systems of the plant. (author)

Tree planting by small producers in the tropics: A comparative study of Brazil and Panama.

Science.gov (United States)

Cynthia S. Simmons; Robert T. Walker; Charles H. Wood

2002-01-01

Forest regrowth is a notable phenomenon across the tropical forest latitudes. Such reforestation takes place in the wake of land abandonment, occurs cyclically in a rotational agricultural system, and may result from the deliberate planting of trees by farmers. Although less extensive than successional forest regeneration, tree planting by small farmers can have...

Multi-fuel multi-product operation of IGCC power plants with carbon capture and storage (CCS)

International Nuclear Information System (INIS)

Cormos, Ana-Maria; Dinca, Cristian; Cormos, Calin-Cristian

2015-01-01

This paper investigates multi-fuel multi-product operation of IGCC plants with carbon capture and storage (CCS). The investigated plant designs co-process coal with different sorts of biomass (e.g. sawdust) and solid wastes, through gasification, leading to different decarbonised energy vectors (power, hydrogen, heat, substitute natural gas etc.) simultaneous with carbon capture. Co-gasification of coal with different renewable energy sources coupled with carbon capture will pave the way towards zero emissions power plants. The energy conversions investigated in the paper were simulated using commercial process flow modelling package (ChemCAD) in order to produce mass and energy balances necessary for the proposed evaluation. As illustrative cases, hydrogen and power co-generation and Fischer–Tropsch fuel synthesis (both with carbon capture), were presented. The case studies investigated in the paper produce a flexible ratio between power and hydrogen (in the range of 400–600 MW net electricity and 0–200 MW th hydrogen considering the lower heating value) with at least 90% carbon capture rate. Special emphasis were given to fuel selection criteria for optimisation of gasification performances (fuel blending), to the selection criteria for gasification reactor in a multi-fuel multi-product operation scenario, modelling and simulation of whole process, to thermal and power integration of processes, flexibility analysis of the energy conversion processes, in-depth techno-economic and environmental assessment etc. - Highlights: • Assessment of IGCC-based energy vectors poly-generation systems with CCS. • Optimisation of gasification performances and CO 2 emissions by fuel blending. • Multi-fuel multi-product operation of gasification plants

Radionuclide contaminant analysis of small mammels, plants and sediments within Mortandad Canyon, 1994

International Nuclear Information System (INIS)

Bennett, K.; Biggs, J.; Fresquez, P.

1996-01-01

Small mammals, plants and sediments were sampled at one upstream location (Site 1) and two downstream locations (Site 2 and Site 3) from the National Pollution Discharge Elimination System outfall number-sign 051-051 in Mortandad Canyon, Los Alamos County, New Mexico. The purpose of the sampling was to identify radionuclides potentially present, to quantitatively estimate and compare the amount of radionuclide uptake at specific locations (Site 2 and Site 3) within Mortandad Canyon to an upstream site (Site 1), and to identify the primary mode (inhalation ingestion, or surface contact) of contamination to small mammals. Three composite samples of at least five animals per sample were collected at each site. Pelts and carcasses of each animal were separated and analyzed independently. In addition, three composite samples were also collected for plants and sediments at each site. Samples were analyzed for 241 Am, 90 Sr, 238 Pu, 239 Pu, and total U. With the exception of total U, all mean radionuclide concentrations in small mammal carcasses and sediments were significantly higher at Site 2 than Site 1 or Site 3. No differences were detected in the mean radionuclide concentration of plant samples between sites. However, some radionuclide concentrations found at all three sites were higher than regional background. No differences were found between mean carcass radionuclide concentrations and mean pelt radionuclide concentrations, indicating that the two primary modes of contamination may be equally occurring

Economic competitiveness of small modular reactors versus coal and combined cycle plants

International Nuclear Information System (INIS)

Alonso, Gustavo; Bilbao, Sama; Valle, Edmundo del

2016-01-01

Small modular reactors (SMRs) may be an option to cover the electricity needs of isolated regions, distributed generation grids and countries with small electrical grids. Previous analyses show that the overnight capital cost for SMRs is between 4500 US$/kW and 5350 US$/kW, which is between a 6% and a 26% higher than the average cost of a current large nuclear reactor. This study analyzes the economic competitiveness of small modular reactors against thermal plants using coal and natural gas combined cycle plants. To assess the economic competitiveness of SMRs, three overnight capital costs are considered 4500 US$/kW, 5000 US$/kW and 5350 US$/kW along with three discount rates for each overnight cost considered, these are 3, 7, and 10%. To compare with natural gas combined cycle (CC) units, four different gas prices are considered, these are 4.74 US$/GJ (5 US$/mmBTU), 9.48 US$/GJ (10 US$/mmBTU), 14.22 US$/GJ (15 US$/mmBTU), and 18.96 US$/GJ (20 US$/mmBTU). To compare against coal, two different coal prices are considered 80 and 120 US$/ton of coal. The carbon tax considered, for both CC and coal, is 30 US$/ton CO_2. The results show what scenarios make SMRs competitive against coal and/or combined cycle plants. In addition, because the price of electricity is a key component to guarantee the feasibility of a new project, this analysis calculates the price of electricity for the economically viable deployment of SMRs in all the above scenarios. In particular, this study shows that a minimum price of electricity of 175 US$/MWh is needed to guarantee the feasibility of a new SMR, if its overnight capital cost is 5350 US$/kWe and the discount rate is 10%. Another result is that when the price of electricity is around 100 US$/MWh then the discount rate must be around 7% or less to provide appropriate financial conditions to make SMRs economically feasible. - Highlights: • Small modular reactor (SMR) are economically assessed. • SMR are compared against gas and coal

Potential advantages and disadvantages of sequentially building small nuclear units instead of a large nuclear plant

International Nuclear Information System (INIS)

Feretic, D.; Cavlina, N.; Grgic, D.

2008-01-01

Renewal of nuclear power programs in countries with modest electricity consumptions and weak electrical grid interconnections has raised the question of optimal nuclear power plants sizes for such countries. The same question would be also valid for isolated or weakly connected regions within a large country. Building large size nuclear power plant could be prevented by technical or financial limits. Research programs have been initiated in the International Atomic Energy Agency and in the USA (within the framework of the Global Nuclear Energy Partnership (GNEP) program) with the aim to inspect under which circumstances small and medium reactors could be the preferred option compared to large nuclear plants. The economy of scale is a clear advantage of large plants. This paper compares, by using probabilistic methods, the net cash flow of large and medium size plants, taking as example a large nuclear plant (around 1200 MW) and four sequentially built smaller plants (300 MW). Potential advantages and disadvantageous of both options have been considered. Main advantages of the sequential construction of several identical small units could be the reduced investor risk and reduced investment costs due to the learning effect. This analysis is a part of studies for the Croatian power generating system development. (orig.)

The impact of lignocellulosic ethanol yields in polygeneration with district heating – A case study

International Nuclear Information System (INIS)

Starfelt, Fredrik; Daianova, Lilia; Yan, Jinyue; Thorin, Eva; Dotzauer, Erik

2012-01-01

Highlights: ► We model a system with ethanol, power and district heating production. ► Different ethanol yields are investigated from an overall system perspective. ► Yields of ethanol production have less importance for the profitability of the plant. -- Abstract: The development towards high energy efficiency and low environmental impact from human interactions has led to changes at many levels of society. As a result of the introduction of penalties on carbon dioxide emissions and other economic instruments, the energy industry is striving to improve energy efficiency and climate mitigation by switching from fossil fuels to renewable fuels. Biomass-based combined heat and power (CHP) plants connected to district heating networks have a need to find uses for the excess heat they produce in summer when the heat demand is low. On the other hand, the transport sector makes a substantial contribution to the increasing CO 2 emissions, which have to be reduced. One promising alternative to address these challenging issues is the integration of vehicle fuel production with biomass-based CHP plants. This paper presents the configuration and operating profits in terms of electricity, heat and ethanol fuel from cellulosic biomass. A case study of a commercial small scale CHP plant was conducted using simulation and modeling tools. The results clearly show that electricity production can be increased when CHP production is integrated with cellulosic ethanol production. The findings also show that the economic benefits of the energy system can be realized with near-term commercially available technology, and that the benefits do not rely solely on ethanol yields.

A novel solar-assisted heat pump driven by photovoltaic/thermal collectors: Dynamic simulation and thermoeconomic optimization

International Nuclear Information System (INIS)

Calise, Francesco; Dentice d'Accadia, Massimo; Figaj, Rafal Damian; Vanoli, Laura

2016-01-01

This paper presents a dynamic simulation model and a thermo-economic analysis of a novel polygeneration system based on a solar-assisted heat pump and an adsorption chiller, both driven by PVT (photovoltaic/thermal) collectors. The aim of this work is to design and dynamically simulate a novel ultra-high efficient solar heating and cooling system. The overall plant layout is designed to supply electricity, space heating and cooling and domestic hot water for a small residential building. The system combines solar cooling, solar-assisted heat pump and photovoltaic/thermal collector technologies in a novel solar polygeneration system. In fact, the polygeneration system is based on a PVT solar field, coupled with a water-to-water electric heat pump or to an adsorption chiller. PVT collectors simultaneously produce electricity and thermal energy. During the winter, hot water produced by PVT collectors primarily supplies the evaporator of the heat pump, whereas in summer, solar energy supplies an adsorption chiller providing the required space cooling. All year long, solar thermal energy in excess is converted into DHW (domestic hot water). The system model was developed in TRNSYS environment. 1-year dynamic simulations are performed for different case studies in various weather conditions. The results are analysed on different time bases presenting energetic, environmental and economic performance data. Finally, a sensitivity analysis and a thermoeconomic optimization were performed, in order to determine the set of system design/control parameters that minimize the simple pay-back period. The results showed a total energy efficiency of the PVT of 49%, a heat pump yearly coefficient of performance for heating mode above 4 and a coefficient of performance of the adsorption chiller of 0.55. Finally, it is also concluded that system performance is highly sensitive to the PVT field area. The system is profitable when a capital investment subsidy of 50% is considered

Phytophthora effector targets a novel component of small RNA pathway in plants to promote infection.

Science.gov (United States)

Qiao, Yongli; Shi, Jinxia; Zhai, Yi; Hou, Yingnan; Ma, Wenbo

2015-05-05

A broad range of parasites rely on the functions of effector proteins to subvert host immune response and facilitate disease development. The notorious Phytophthora pathogens evolved effectors with RNA silencing suppression activity to promote infection in plant hosts. Here we report that the Phytophthora Suppressor of RNA Silencing 1 (PSR1) can bind to an evolutionarily conserved nuclear protein containing the aspartate-glutamate-alanine-histidine-box RNA helicase domain in plants. This protein, designated PSR1-Interacting Protein 1 (PINP1), regulates the accumulation of both microRNAs and endogenous small interfering RNAs in Arabidopsis. A null mutation of PINP1 causes embryonic lethality, and silencing of PINP1 leads to developmental defects and hypersusceptibility to Phytophthora infection. These phenotypes are reminiscent of transgenic plants expressing PSR1, supporting PINP1 as a direct virulence target of PSR1. We further demonstrate that the localization of the Dicer-like 1 protein complex is impaired in the nucleus of PINP1-silenced or PSR1-expressing cells, indicating that PINP1 may facilitate small RNA processing by affecting the assembly of dicing complexes. A similar function of PINP1 homologous genes in development and immunity was also observed in Nicotiana benthamiana. These findings highlight PINP1 as a previously unidentified component of RNA silencing that regulates distinct classes of small RNAs in plants. Importantly, Phytophthora has evolved effectors to target PINP1 in order to promote infection.

Estimation of the cost of electro-mechanical equipment for small hydropower plants – review and comparison of methods

Directory of Open Access Journals (Sweden)

Lipiński Seweryn

2017-01-01

Full Text Available The estimate of the cost of electro-mechanical equipment for new small hydropower plants most often amounts to about 30-40% of the total budget. In case of modernization of existing installations, this estimation represents the main cost. This matter constitutes a research problem for at least few decades. Many models have been developed for that purpose. The aim of our work was to collect and analyse formulas that allow estimation of the cost of investment in electro-mechanical equipment for small hydropower plants. Over a dozen functions were analysed. To achieve the aim of our work, these functions were converted into the form allowing their comparison. Then the costs were simulated with respect to plants’ powers and net heads; such approach is novel and allows deeper discussion of the problem, as well as drawing broader conclusions. The following conclusions can be drawn: significant differences in results obtained by using various formulas were observed; there is a need for a wide study based on national investments in small hydropower plants that would allow to develop equations based on local data; the obtained formulas would let to determinate the costs of modernization or a new construction of small hydropower plant more precisely; special attention should be payed to formulas considering turbine type.

Influence of small hydropower plants on brown trout (Salmo trutta L. population in Mislinja River

Directory of Open Access Journals (Sweden)

Blaž Cokan

2013-12-01

Full Text Available The brown trout (Salmo trutta L. in the Mislinja River has been endangered for years because of small hydroelectric power plants. To find out how they are affecting the population of the brown trout in the Mislinja River, we conducted a sampling of the brown trout, using a generating set. We measured the length and weight of all caught specimens and analysed the obtained data. The results are presented in this paper, e.g., biomass, estimations of abundance, average weight, average length and number of captured brown trout. We discovered that the population of the brown trout has decreased in all the sections where water has been taken away for small hydroelectric power plants.

Actual state and perspectives of the small hydroelectric plants in Colombia

International Nuclear Information System (INIS)

Torres Q, E.; Castillo C, J.J.

1995-01-01

In this article, the actual state of the small-scale hydroelectric power plants (PCHs, abbreviations in Spanish) in Colombia in aspects as: Statistic of the water in Colombia, a brief historical review and the characteristics of the PCHs in Colombia, is present. The development PCHs, the executing projects and the actions that has been develop by the INEA (Institute of Nuclear Sciences and the Alternative Energies) is described

Effect of water purification process in radioactive content: analysis on small scale purification plants

International Nuclear Information System (INIS)

Lopez del Rio, H.; Quiroga S, J. C.; Davila R, J. I.; Mireles G, F.

2009-10-01

Water from small scale purification plants is a low cost alternative for consumers in comparison to the bottled commercial presentations. Because of its low cost per liter, the consumption of this product has increased in recent years, stimulating in turn the installation of purification systems for these small businesses. The purpose of this study was to estimate the efficiency of small scale purification systems located in the cities of Zacatecas and Guadalupe, Zacatecas, to reduce the radioactive content of water. It was measured the total alpha and beta activity in water samples of entry and exit to process, through the liquid scintillation technique. In general it was observed that the process is more efficient in removing alpha that beta activity. The fraction of total alpha activity removed varied between 27 and 100%, while between 0 and 77% of the total beta activity was removed by the analyzed plants. In all cases, the total radioactivity level was lower than the maximum permissible value settled by the official mexican standard for drinking water. (Author)

An approach to the investment analysis of small and medium hydro-power plants

International Nuclear Information System (INIS)

Forouzbakhsh, F.; Hosseini, S.M.H.; Vakilian, M.

2007-01-01

Hydro-power plants, as a part of infrastructure projects, play an important role in the economic-social development of countries. Since a large amount of investment is needed for construction of these power plants, which appeared to be an obstacle in these developments, however it is possible to finance these infrastructure plants by assigning these affairs to private sectors by using build operate transfer (BOT) method, which is quite well-known all around the world. This paper reviews the structure of BOT contracts and through an economic evaluation based on different percentage of investments of private sector in providing the expenses of small and medium hydro-power plants (S and M-HPP) (e.g. MHPP in 'Bookan, Iran' and SHPP in 'Nari, Iran'), demonstrates that by increasing the percentage the share of the private sector in the investment, the economic indices B/C and NPV improve substantially

New small HTGR power plant concept with inherently safe features - an engineering and economic challenge

International Nuclear Information System (INIS)

McDonald, C.F.; Sonn, D.L.

1983-01-01

Studies are in a very early design stage to establish a modular concept High-Temperature Gas-Cooled Reactor (HTGR) plant of about 100-MW(e) size to meet the special needs of small energy users in the industrialized and developing nations. The basic approach is to design a small system in which, even under the extreme conditions of loss of reactor pressure and loss of forced core cooling, the temperature would remain low enough so that the fuel would retain essentially all the fission products and the owner's investment would not be jeopardized. To realize economic goals, the designer faces the challenge of providing a standardized nuclear heat source, relying on a high percentage of factory fabrication to reduce site construction time, and keeping the system simple. While the proposed nuclear plant concept embodies new features, there is a large technology base to draw upon for the design of a small HTGR

A small floating seawater desalination plant using a nuclear heating reactor coupled with the MED process

International Nuclear Information System (INIS)

Dong Duo; Wu Shaorong; Zhang Dafang; Wu Zongxin

1997-01-01

A small floating seawater desalination plant using a nuclear heating reactor coupled with a multi-effect distillation (MED) process was designed by the Institute of Nuclear Energy Technology, Tsinghua University of China. It was intended to supply potable water to remove coastal areas or islands where both fresh water and energy are severely lacking, and also to serve as a demonstration and training facility. The design of a small floating plant coupled two proven technologies in the cogeneration mode: a nuclear heating reactor (NHR-10), with inherent, passive safety features based on NHR-5 experience, and a low temperature MED process. The secondary loop was designed as a safety barrier between the primary loop and the steam loop. With a 10 MW(th) heating reactor, the floating plant could provide 4,000 m 3 /d of potable water and 750 kW of electricity. The design concept and parameters, safety features, coupling scheme and floating plant layout are presented in the paper. (author). 3 refs, 4 figs, 3 tabs

Private investment for building a small hydropower plant at Zetea dam base

International Nuclear Information System (INIS)

Popa, Florica; Paraschivescu, Adina; Vladescu, Aurelia; Popa, Bogdan

2007-01-01

Zetea lake grading project comprises an earthen dam, made out of local materials, having as main purposes water supply, flood control and protection against flooding. The paper analyzes the possibility of building a small hydropower plant at the base of the dam, using private investment resources, in order to put to good use the water flow evacuated from the storage lake. (authors)

Cost analysis of small hydroelectric power plants components and preliminary estimation of global cost

International Nuclear Information System (INIS)

Basta, C.; Olive, W.J.; Antunes, J.S.

1990-01-01

An analysis of cost for each components of Small Hydroelectric Power Plant, taking into account the real costs of these projects is shown. It also presents a global equation which allows a preliminary estimation of cost for each construction. (author)

Phytoremediation of small organic contaminants using transgenic plants

Science.gov (United States)

James, C Andrew; Strand, Stuart E

2010-01-01

The efficacy of transgenic plants in the phytoremediation of small organic contaminants has been investigated. Two principal strategies have been pursued (1) the manipulation of phase I metabolic activity to enhance in planta degradation rates, or to impart novel metabolic activity, and (2) the enhanced secretion of reactive enzymes from roots leading to accelerated ex planta degradation of organic contaminants. A pair of dehalogenase genes from Xanthobacter autotrophicus was expressed in tobacco resulting in the dehalogenation of 1,2-dichloroethane, which was otherwise recalcitrant. A laccase gene from cotton was overexpressed in Arabidopsis thaliana resulting in increased secretory laccase activity and the enhanced resistance to trichlorophenol in soils. Although the results to date are promising, much of the work has been limited to laboratory settings; field demonstrations are needed. PMID:19342219

Small-scale hydroelectric power plant of Passo do Inferno automation system; Sistema de automatizacao da PCH Passo do Inferno

Energy Technology Data Exchange (ETDEWEB)

Santos, Luiz C. Lisboa; Moralles, Reni; Quadros, Carlos A.D.; Martiny, Raul; Moehlecke, Juarez E.; Costa, Nelson D. da; Cesar, Rogerio L.; Santos, Sergio S.; Basei, Eleu Natal [Companhia Estadual de Energia Eletrica do Estado do Rio Grande do Sul, Porto Alegre, RS (Brazil)

1993-12-31

This work introduces the automation system brought into the 1,7 MVA small-scale hydroelectric power plant of Passo do Inferno, state of Rio Grande do Sul, Brazil. The following systems are presented: supervision, security and generation control, as well as the program and the controller. In this work, it is focused the generation control system, as a new outfitted system in small-scale hydroelectric power plants 3 figs.

An approach to the investment analysis of small and medium hydro-power plants

Energy Technology Data Exchange (ETDEWEB)

Forouzbakhsh, F. [University of Tehran (Iran). Faculty of Engineering; Hosseini, S.M.H. [Islamic Azad University, Tehran (Iran). Faculty of Engineering; Vakilian, M. [Sharif Institute of Technology, Tehran (Iran). Faculty of Electrical Engineering

2007-02-15

Hydro-power plants, as a part of infrastructure projects, play an important role in the economic-social development of countries. Since a large amount of investment is needed for construction of these power plants, which appeared to be an obstacle in these developments, however it is possible to finance these infrastructure plants by assigning these affairs to private sectors by using build operate transfer (BOT) method, which is quite well-known all around the world. This paper reviews the structure of BOT contracts and through an economic evaluation based on different percentage of investments of private sector in providing the expenses of small and medium hydro-power plants (S and M-HPP) (e.g. MHPP in ''Bookan, Iran'' and SHPP in ''Nari, Iran''), demonstrates that by increasing the percentage the share of the private sector in the investment, the economic indices B/C and NPV improve substantially. (author)

A METHOD OF RAPID CULTIVATION OF RADISH SEED PLANTS IN PLASTIC POTS OF SMALL-VOLUME

Directory of Open Access Journals (Sweden)

V. A. Stepanov

2017-01-01

Full Text Available The development of cheap and rapid breeding methods to breed  the lines used for  hybrid  F1  production  is a very actual task. The study was carried out with a use of radish varieties originated at VNIISSOK and breeding lines obtained by crossing components of different origin with male  sterility  in  winter  glass  greenhouse.  The  mother plants were grown  on the trays Plantec 64, while seedplants were grown in plastic pots of 1 liter capacity. The some morphobiological features such as the small habitus of see-plant; smaller number of secondary branching and absence of following branches; and consequently, the low yield of seeds were revealed in seed-plants of radish being grown in plastic pots. The period of ontogenesis in radish at first winter-spring rotation with this cultivation approach was reduced to 92 days. At the second summer-autumn rotation with additional lighting the duration of period of ontogenesis was essentially shorter than in the first rotation.  The utilization of  small-volume capacities in winter glass greenhouse to grow the radish seed-plants has permitted to produce two generations a year.

A novel polygeneration system integrating photovoltaic/thermal collectors, solar assisted heat pump, adsorption chiller and electrical energy storage: Dynamic and energy-economic analysis

International Nuclear Information System (INIS)

Calise, Francesco; Figaj, Rafal Damian; Vanoli, Laura

2017-01-01

Highlights: • Space heating/cooling, domestic hot water and electrical energy are provided by the system. • Two different users are investigated: fitness center and office. • The influence of the battery system on system economic performance is scarce. • Net metering contract is more profitable compared to simplified purchase/resale arrangement one. - Abstract: In this paper a dynamic simulation model and a thermo-economic analysis of a novel polygeneration system are presented. The system includes photovoltaic/thermal collectors coupled with a solar-assisted heat pump, an adsorption chiller and an electrical energy storage. The modelled plant supplies electrical energy, space heating and cooling and domestic hot water. The produced solar thermal energy is used during the winter to supply the heat pump evaporator, providing the required space heating. In summer, solar thermal energy is used to drive an adsorption chiller providing the required space cooling. All year long, solar thermal energy in excess, with respect to the space heating and cooling demand, is used to produce domestic hot water. The produced electrical energy is self-consumed by both user and system auxiliary equipment and/or supplied to the grid. The system model includes a detailed electrical energy model for user storage and exchange with the grid along with a detailed building model. This study is a continuation of previous works recently presented by the authors. In particular, the present paper focuses on the real electrical demands of several types of users and on the analysis of the comfort of building users. Differently from the works previously published by the authors, the present work bases the calculations on measured electrical demands of real users (fitness center and offices). The system performance is analyzed with two different electricity supply contracts: net metering and simplified purchase/resale arrangement. Daily, weekly and yearly results are presented. Finally, a

psRNATarget: a plant small RNA target analysis server (2017 release).

Science.gov (United States)

Dai, Xinbin; Zhuang, Zhaohong; Zhao, Patrick Xuechun

2018-04-30

Plant regulatory small RNAs (sRNAs), which include most microRNAs (miRNAs) and a subset of small interfering RNAs (siRNAs), such as the phased siRNAs (phasiRNAs), play important roles in regulating gene expression. Although generated from genetically distinct biogenesis pathways, these regulatory sRNAs share the same mechanisms for post-translational gene silencing and translational inhibition. psRNATarget was developed to identify plant sRNA targets by (i) analyzing complementary matching between the sRNA sequence and target mRNA sequence using a predefined scoring schema and (ii) by evaluating target site accessibility. This update enhances its analytical performance by developing a new scoring schema that is capable of discovering miRNA-mRNA interactions at higher 'recall rates' without significantly increasing total prediction output. The scoring procedure is customizable for the users to search both canonical and non-canonical targets. This update also enables transmitting and analyzing 'big' data empowered by (a) the implementation of multi-threading chunked file uploading, which can be paused and resumed, using HTML5 APIs and (b) the allocation of significantly more computing nodes to its back-end Linux cluster. The updated psRNATarget server has clear, compelling and user-friendly interfaces that enhance user experiences and present data clearly and concisely. The psRNATarget is freely available at http://plantgrn.noble.org/psRNATarget/.

Small mammals as indicators of cryptic plant species diversity in the central Chilean plant endemicity hotspot

Directory of Open Access Journals (Sweden)

Meredith Root-Bernstein

2014-12-01

Full Text Available Indicator species could help to compensate for a shortfall of knowledge about the diversity and distributions of undersampled and cryptic species. This paper provides background knowledge about the ecological interactions that affect and are affected by herbaceous diversity in central Chile, as part of the indicator species selection process. We focus on the ecosystem engineering role of small mammals, primarily the degu Octodon degus. We also consider the interacting effects of shrubs, trees, avian activity, livestock, slope, and soil quality on herbaceous communities in central Chile. We sampled herbaceous diversity on a private landholding characterized by a mosaic of savanna, grassland and matorral, across a range of degu disturbance intensities. We find that the strongest factors affecting endemic herbaceous diversity are density of degu runways, shrub cover and avian activity. Our results show that the degu, a charismatic and easily identifiable and countable species, could be used as an indicator species to aid potential conservation actions such as private protected area uptake. We map areas in central Chile where degus may indicate endemic plant diversity. This area is larger than expected, and suggests that significant areas of endemic plant communities may still exist, and should be identified and protected. Keywords: Cryptic species, Diversity, Endemic, Indicator species, Octodon degus, Plant

Single-tube hydroponics as a novel idea for small-scale production of crop seed in a plant incubator.

Science.gov (United States)

Kuroda, Masaharu; Ikenaga, Sachiko

2015-01-01

We present a novel protocol for small-scale production of crop seed in a plant incubator termed "Single-tube hydroponics." Our protocol minimizes the materials and methods for cultivation whereby a large number of independent plants can be cultured in a limited space. This study may aid in the improvement of crop seed components, especially in the cultivation of transgenic plants.

Small-medium sized nuclear coal and gas power plant: A probabilistic analysis of their financial performances and influence of CO2 cost

International Nuclear Information System (INIS)

Locatelli, Giorgio; Mancini, Mauro

2010-01-01

Nations or regions with limited electrical grid and restricted financial resources are a suitable market for small medium power plants with a size of 300-400 MWe. The literature presents several comparisons about the economics of large power plants (of about 1000 MWe); however there are not probabilistic analysis regarding the economics of small medium power plants. This paper fills this gap comparing, with a Monte Carlo evaluation, the economical and financial performances of a nuclear reactor, a coal fired power plant and a combined cycle gas turbine (CCGT) of 335 MWe. The paper aims also to investigate the effect of the carbon tax and electrical energy price on the economics of these plants. The analysis show as, without any carbon tax, the coal plant has the lowest levelised unit electricity cost (LUEC) and the highest net present value (NPV). Introducing the carbon tax the rank changes: depending on its amount the first and the nuclear after becomes the plant with lower LUEC and highest NPV. Therefore, the uncertainty in the carbon tax cost increases the risk of investing in a coal plant above the level of the new small medium reactor.

The Green Integrated Forest Biorefinery: An innovative concept for the pulp and paper mills

International Nuclear Information System (INIS)

Rafione, Tatiana; Marinova, Mariya; Montastruc, Ludovic; Paris, Jean

2014-01-01

The Green Integrated Forest Biorefinery (GIFBR), a new concept suitable for implementation in pulp and paper mills is characterized by low greenhouse gases emissions, reduced water consumption and production of effluents. Its fossil fuel consumption must be nil. Several challenges have to be addressed to develop a sustainable GIFBR facility. An implementation strategy by phase is proposed to schedule the total capital investment over several years and to mitigate the economic risks associated with the transformation of an existing pulp and paper mill into a GIFBR. In the first phase of the methodology, the receptor mill and the biorefinery plant are selected. An intensive energy and material integration of the two plants is performed in the second phase, then a gasification unit is implemented and, finally a polygeneration unit is installed. The methodology is illustrated by application to a case study based on a reference Canadian Kraft mill. Each phase of the implementation strategy of the GIFBR is described. - Highlights: • The Green Integrated Forest Biorefinery (GIFBR) is a new biorefinery concept. • A GIFBR includes a pulp mill, a biorefinery, a gasification and a polygeneration units. • An implementation strategy by phase is proposed to successfully develop a GIFBR. • To determine achievable level of integration between the GIFBR constituents is crucial. • GIFBR concept technically and economically feasibility for pulp and paper mills

Indirect coal liquefaction - the first commercial CTL project in the USA

Energy Technology Data Exchange (ETDEWEB)

Radtke, K.; Battensby, D.; Marsico, C.; Hooper, M.; Mather, C. [Uhde GmbH (Germany)

2006-07-01

The polygeneration of fuels, chemical and power offers an innovative and economically advantageous way to utilise disadvantaged fuels, such as lignite, waste coal and petroleum coke, in a coal-to-liquids (CTL) plant by means of integration of three main process blocks: gasification island to convert coal into clean synthesis gas; Fischer-Tropsch synthesis to convert synthesis gas into clean liquid fuels and chemicals; and combustion of synthesis gas to produce electric power and steam. This paper describes the process and technology side of this indirect coal liquefaction project with key plant data that has been elaborated for a commercial scale CTL project, which is expected to be the first CTL plant in the USA. The plant will use the Shell Coal Gasification process. 6 figs.

INEL design studies in support of the Westinghouse EPRI small plant study

International Nuclear Information System (INIS)

Burtt, J.D.; Kullberg, C.M.

1986-03-01

In support of the design effort of a Westinghouse EPRI small plant study, several analyses were performed at the Idaho National Engineering Laboratory. An analysis was performed to study fuel behavior under conditions of a limiting flow coastdown transient. Depressurization capabilities for the reactor coolant system were studied. The post-accident heat removal for the current containment design was studied. The results of all three studies are reported. 31 figs

Using small RNA (sRNA) deep sequencing to understand global virus distribution in plants

Science.gov (United States)

Small RNAs (sRNAs), a class of regulatory RNAs, have been used to serve as the specificity determinants of suppressing gene expression in plants and animals. Next generation sequencing (NGS) uncovered the sRNA landscape in most organisms including their associated microbes. In the current study, w...

Prediction of small hydropower plant power production in Himreen Lake dam (HLD using artificial neural network

Directory of Open Access Journals (Sweden)

Ali Thaeer Hammid

2018-03-01

Full Text Available In developing countries, the power production is properly less than the request of power or load, and sustaining a system stability of power production is a trouble quietly. Sometimes, there is a necessary development to the correct quantity of load demand to retain a system of power production steadily. Thus, Small Hydropower Plant (SHP includes a Kaplan turbine was verified to explore its applicability. This paper concentrates on applying on Artificial Neural Networks (ANNs by approaching of Feed-Forward, Back-Propagation to make performance predictions of the hydropower plant at the Himreen lake dam-Diyala in terms of net turbine head, flow rate of water and power production that data gathered during a research over a 10 year period. The model studies the uncertainties of inputs and output operation and there's a designing to network structure and then trained by means of the entire of 3570 experimental and observed data. Furthermore, ANN offers an analyzing and diagnosing instrument effectively to model performance of the nonlinear plant. The study suggests that the ANN may predict the performance of the plant with a correlation coefficient (R between the variables of predicted and observed output that would be higher than 0.96. Keywords: Himreen Lake Dam, Small Hydropower plants, Artificial Neural Networks, Feed forward-back propagation model, Generation system's prediction

Hydro-economic performances of streamflow withdrawal strategies: the case of small run-of-river power plants

Science.gov (United States)

Basso, Stefano; Lazzaro, Gianluca; Schirmer, Mario; Botter, Gianluca

2014-05-01

River flows withdrawals to supply small run-of-river hydropower plants have been increasing significantly in recent years - particularly in the Alpine area - as a consequence of public incentives aimed at enhancing energy production from renewable sources. This growth further raised the anthropic pressure in areas traditionally characterized by an intense exploitation of water resources, thereby triggering social conflicts among local communities, hydropower investors and public authorities. This brought to the attention of scientists and population the urgency for novel and quantitative tools for assessing the hydrologic impact of these type of plants, and trading between economic interests and ecologic concerns. In this contribution we propose an analytical framework that allows for the estimate of the streamflow availability for hydropower production and the selection of the run-of-river plant capacity, as well as the assessment of the related profitability and environmental impacts. The method highlights the key role of the streamflow variability in the design process, by showing the significance control of the coefficient of variation of daily flows on the duration of the optimal capacity of small run-of-river plants. Moreover, the analysis evidences a gap between energy and economic optimizations, which may result in the under-exploitation of the available hydropower potential at large scales. The disturbances to the natural flow regime produced between the intake and the outflow of run-of-river power plants are also estimated within the proposed framework. The altered hydrologic regime, described through the probability distribution and the correlation function of streamflows, is analytically expressed as a function of the natural regime for different management strategies. The deviations from pristine conditions of a set of hydrologic statistics are used, jointly with an economic index, to compare environmental and economic outcomes of alternative plant

On the Analysis and Fault-Diagnosis Tools for Small-Scale Heat and Power Plants

Energy Technology Data Exchange (ETDEWEB)

Arriagada, Jaime

2003-12-01

The deregulation of the electricity market drives utilities and independent power producers to operate heat and power plants as profit centers. In order to keep the economic margins on the credit side, the preferred measures have been to improve the electrical efficiency through changes in the hardware and boost the overall efficiency through e.g. combined heat and power (CHP) generation. The better understanding of global environmental issues is also pushing the development toward more advanced power plant technology that at the introduction stage may represent a risky option for the plant owner. Recently, there is a growing interest in improving the plant operation instead, and therefore the focus has been put on aspects related to the RAM (reliability-availability-maintenance) of the plants. Small- and mid-scale CHP plants, especially natural gas- and biomass-fueled, have been identified to be important to satisfy the needs of the energy market and help to mitigate the environmental factors in the short- and middle-term. One of the major challenges that these types of plants will face is attaining good RAM at the same time that they cannot support big O and M costs and a lot of personnel. Therefore the implementation of cheap and reliable IT-based tools that help to achieve this goal is essential. Most power plants today are equipped with modern distributed control systems that through a considerable number of sensors deliver large amounts of data to the control room. This paves the way to the introduction of intelligent tools - derived from the artificial intelligence technology - such as artificial neural networks (ANNs) and genetic algorithms (GA). ANNs have a learning ability that makes them useful for the construction of powerful non-physical models based on data from the process, while GA has shown to be a robust optimization method based on the principle of the 'survival-of-the-fittest'. Principally ANNs, but also to a lesser extent GA, have

Sustainable siting procedure of small hydroelectric plants: The Greek experience

International Nuclear Information System (INIS)

Tsoutsos, Theocharis; Maria, Efpraxia; Mathioudakis, Vassilis

2007-01-01

This paper aims to present the procedure under which a sustainable plant, like a small hydroelectric plant (SHP), can be installed and deployed, especially in countries with complicated administrative and legislative systems. Those must be defined by the rules that characterize sustainable spatial planning, which aims at the environmental protection, the insurance of better living conditions and finally at the economic development within the frame of the principle of sustainability and its three basic dimensions: social, economical and environmental. The main principles of spatial planning are accepted from the jurisprudence of the Hellenic Council of State, either as an appropriate condition for the protection of important ecosystems or as specific expression of the principle of prevention of environmental damage. In this framework it is accepted that the development is experienced, initially to a total and general planning, whose essential part is the assessment and modification of distributed land uses. Besides, the main characteristics of the siting of SHPs and the criteria demanded for their smooth integration and operation are presented

Design of a Small Scale Pilot Biodiesel Production Plant and Determination of the Fuel Properties of Biodiesel Produced With This Plant

Directory of Open Access Journals (Sweden)

Tanzer Eryılmaz

2014-09-01

Full Text Available A small scale pilot biodiesel production plant that has a volume of 65 liters/day has been designed, constructed and tested. The plant was performed using oil mixture (50% wild mustard seed oil + 50% refined canola oil and methanol with sodium hydroxide (NaOH catalyst. The fuel properties of biodiesel indicated as density at 15oC (889.64 kg/m3, kinematic viscosity at 40oC (6.975 mm2/s, flash point (170oC, copper strip corrosion (1a, water content (499.87 mg/kg, and calorific value (39.555 MJ/kg, respectively.

THE CHOICE OF THE GENERATOR AND ELECTRICITY STABILIZATION FOR SMALL HYDROPOWER PLANTS

OpenAIRE

Kvitko A. V.; Daybova L. A.; Kondratenko Y. E.

2015-01-01

The article analyzes the main characteristics of the electricity generators to use them as a part of small hydroelectric power plants. It is shown, that contactless asynchronous generators in comparison with synchronous generators and DC generators have improved their operational and technical characteristics, and above all, their reliability and performance efficiency. We have shown graphic dependences of the cost and the weight of power generators. It is proposed using direct frequency conv...

A study of a small nuclear power plant system for district heating

International Nuclear Information System (INIS)

Imamura, Mitsuru; Sato, Kotaro; Narabayashi, Tadashi; Shimazu, Yoichiro; Tsuji, Masashi

2009-01-01

We have studied nuclear power plant for district heating. Already some towns and villages in Hokkaido have requested small reactor for district heating. Using existing technology allows us to shorten development period and to keep a lid on development cost. We decided to develop new reactor based on 'MUTSU' reactor technology because 'MUTSU' had already proved its safety. And this reactor was boron free reactor. It allows plant system to reduce the chemical control system. And moderator temperature coefficient is deeply negative. It means to improve its operability and leads to dependability enhancement. We calculated burn-up calculation of erbium addition fuel. In the result, the core life became about 10 years. And we adapt the cassette type refueling during outagein in order to maintain nonproliferation. In the district heating system, a double heat exchanger system enables to response to load change in season. To obtain the acceptance of public, this system has a leak prevention system of radioactive materials to public. And road heating system of low grade heat utilization from turbine condenser leads to improve the heat utilization efficiency. We carried out performance evaluation test of district heating pipeline. Then the heat loss of pipeline is estimated at about 0.440degC/km. This result meets general condition, which is about 1degC/km. This small plant has passive safety system. It is natural cooling of containment vessel. In case of loss of coolant accident, decay heat can remove by natural convection air cooling after 6 hours. Decay heat within 6 hours can remove by evaporative heat transfer of pool on containment vessel. (author)

A novel design approach for small scale low enthalpy binary geothermal power plants

International Nuclear Information System (INIS)

Gabbrielli, Roberto

2012-01-01

Highlights: ► Off-design analysis of ORC geothermal power plants through the years and the days. ► Thermal degradation of the geothermal source reduces largely the plant performances. ► The plant capacity factor is low if the brine temperature is far from the design value. ► The performances through the life are more important than those at the design point. ► ORC geothermal power plants should be designed with the end-life brine temperature. - Abstract: In this paper a novel design approach for small scale low enthalpy binary geothermal power plants is proposed. After the suction, the hot water (brine) superheats an organic fluid (R134a) in a Rankine cycle and, then, is injected back underground. This fact causes the well-known thermal degradation of the geothermal resource during the years. Hence, the binary geothermal power plants have to operate with conditions that largely vary during their life and, consequently, the most part of their functioning is executed in off-design conditions. So, as the novel approach here proposed, the design temperature of the geothermal resource is selected between its highest and lowest values, that correspond to the beginning and the end of the operative life of the geothermal power plant, respectively. Hence, using a detailed off-design performance model, the optimal design point of the geothermal power plant is evaluated maximizing the total actualized cash flow from the incentives for renewable power generation. Under different renewable energy incentive scenarios, the power plant that is designed using the lowest temperature of the geothermal resource always results the best option.

Flowering and fruiting intensity of small - sized tomato, due to the regulation of the quantity of light reaching the plant top

Directory of Open Access Journals (Sweden)

Renata Dobromilska

2012-12-01

Full Text Available The experiments were carried out in 2001-2003 in a high unheated plastic tunnel. The influence of reduction of leaves and application of reflection matter on flowering and fruiting of small-sized tomato was studied. The experiment focused on the following factors: methods of increasing the amount of light in plant tops (reflection matter, cutting leaves, reflection matter + cutting leaves and cultivars of small sized tomato ('Conchita F1', 'Picolino F1'. The cutting of leaves and reflection matter mulching resulted in the increase of the intensity of radiation reaching plant tops and the reflected radiation. The above measures increasing the light access to plant tops significantly increased the number of flowers, germs and fruits. The reflection matter mulching along with cutting leaves resulted in the substantial growth of early yield of small-sized tomato. The 'Conchita F1' cultivar set a relatively greater number of flowers and fruits on a plant and in cluster than 'Picolino F1'.

A small capacity co generative gas-turbine plant in factory AD 'Komuna' - Skopje (Macedonia)

International Nuclear Information System (INIS)

Dimitrov, Konstantin; Armenski, Slave; Tashevski, Done

2000-01-01

The factory AD 'Komuna' -Skopje (Macedonia), has two steam block boilers, type ST 800 for steam production for process and space heating. The factory satisfies the electricity needs from the national grid. By the use of natural gas like fuel it is possible to produce electrical energy in its own co generative gas turbine plant. In this article, a co generative plant with small-scale gas turbine for electricity production is analyzed . The gas from gas turbine have been introduce in the steam block boiler. Also, a natural gas consumption, the electricity production, total investment and payback period of investment are determined. (Authors)

Pollution control activities for waste-water treatment plants: planning, integrated approach, functionality controls and small plants

International Nuclear Information System (INIS)

Serena, F.; Tomiato, L.; Ostoich, M.; Falletti, L.

2009-01-01

The work presents the problem of the Wastewater Treatment Plants' (WWTPs) controls and the organization of the consequential activities with reference to the priorities of the Environmental Agencies through a hierarchy assessment according to the environmental importance of the pressure sources. The European Recommendation 2001/331/EC bases the environmental controls of industrial sites and also of WWTPs on an integrated approach overtaking the simple analytic control; the integrated approach requires documentary, technical, management and analytic controls. The Veneto Regional Environmental Prevention and Protection Agency (ARPAV) has recently developed and applied a check-list for the implementation of the European Recommendation for WWTPs. The check-list includes the functionality assessment of the WWTP in case of discharge control delegation to the plant manager as consented with Annex 5 third part Italian Decree 3/04/2006 n. 152. In the paper the general framework of environmental controls on public WWTPs in the Veneto region is described. Particular importance for the numerousness and for the required control typology is referred to the small WWTP ( [it

Project final report: Energetic planning focusing small scale hydroelectric power plants; Relatorio final. Projeto planejamento energetico com enfase em pequenas centrais hidreletricas

Energy Technology Data Exchange (ETDEWEB)

Costa, Yara dos Santos

1994-12-31

Considering the increasing need for a better utilization of the Brazilian hydric resources, a deeper analysis of small scale hydroelectric power plants has been demanding. This work presents a case study of energetic planning based upon small scale hydroelectric power plants in a district of Amazon state - North Brazil 8 refs., 11 figs., 19 tabs.

Experimental results and thermodynamic analysis of a natural gas small scale cogeneration plant for power and refrigeration purposes

International Nuclear Information System (INIS)

Bazzo, Edson; Nacif de Carvalho, Alvaro; Matelli, José Alexandre

2013-01-01

In this work, experimental results are reported for a small scale cogeneration plant for power and refrigeration purposes. The plant includes a natural gas microturbine and an ammonia/water absorption chiller fired by steam. The system was tested under different turbine loads, steam pressures and chiller outlet temperatures. An evaluation based on the 1st and 2nd Laws of Thermodynamics was also performed. For the ambient temperature around 24 °C and microturbine at full load, the plant is able to provide 19 kW of saturated steam at 5.3 bar (161 °C), corresponding to 9.2 kW of refrigeration at −5 °C (COP = 0.44). From a 2nd law point-of-view, it was found that there is an optimal chiller outlet temperature that maximizes the chiller exergetic efficiency. As expected, the microturbine presented the highest irreversibilities, followed by the absorption chiller and the HRSG. In order to reduce the plant exergy destruction, it is recommended a new design for the HRSG and a new insulation for the exhaust pipe. -- Highlights: • A small scale cogeneration plant for power and refrigeration is proposed and analyzed. • The plant is based on a microturbine and a modified absorption chiller. • The plant is analysed based on 1st and 2nd laws of thermodynamics. • Experimental results are found for different power and refrigeration conditions. • The plant proved to be technically feasible

The atypical genesis and bioavailability of the plant-based small RNA MIR2911: Bulking up while breaking down

Science.gov (United States)

The uptake of dietary plant small RNAs (sRNAs) in consumers remains controversial, which is mainly due to low dietary content in combination with poor fractional absorption. MIR2911, among all the plant sRNAs including microRNAs, has been shown to be one of the most robustly absorbed sRNAs. Here we ...

OVERVIEW OF A NEW METHOD FOR DESIGNING HIGH EFFICIENCY SMALL HYDRO POWER PLANTS

Directory of Open Access Journals (Sweden)

Milun Babić

2010-01-01

Full Text Available Significant number of research projects in the area of renewable energy sources (especially for small hydro power plants has been made within the Department for Energy and Process Engineering and Regional Euro Energy Efficiency Center at Faculty of Mechanical Engineering (University of Kragujevac, Serbia since early eighties. The results are various; numerous domestic and international recognition and technical performance tell about the success of the research. Research projects have been following the technical and technological development of research equipment and economy growth. This has led to the development of software for designing turbines of SHP plants. In order to notify the public about possibilities of our software, in this paper is briefly described a mathematical model and procedures for calculating and designing of SHPP for known conditions. As an argument for assessing the validity and potential of our research results is shown constructed SHP plant "Bosnia 1", 2 x 100 kW power.

The small hydropower plant in the old river Aare in Niedergoesgen, Switzerland

International Nuclear Information System (INIS)

Eichenberger, P.

2007-07-01

This preliminary project for the Swiss Federal Office of Energy (SFOE) presents a project which proposes the construction of a new small hydro plant in Niedergoesgen/Gretzenbach, Switzerland, that is to make use of the waters of the old river Aare. The project proposes the construction of a new, 350 kW plant at the site of an existing sill across the old river that originally formed part of a water-power installation given up in 1917. The existing parts of the old installation are described and the legal situation concerning water rights and land ownership are examined. Three variants for a new installation are described. Technical figures and energy-production estimates for a new installation are discussed. Ecological aspects are examined, as are the recreational aspects of the river at this location. Cost estimates and economic viability are discussed.

Sludge reduction in a small wastewater treatment plant by electro-kinetic disintegration.

Science.gov (United States)

Chiavola, Agostina; Ridolfi, Alessandra; D'Amato, Emilio; Bongirolami, Simona; Cima, Ennio; Sirini, Piero; Gavasci, Renato

2015-01-01

Sludge reduction in a wastewater treatment plant (WWTP) has recently become a key issue for the managing companies, due to the increasing constraints on the disposal alternatives. Therefore, all the solutions proposed with the aim of minimizing sludge production are receiving increasing attention and are tested either at laboratory or full-scale to evaluate their real effectiveness. In the present paper, electro-kinetic disintegration has been applied at full-scale in the recycle loop of the sludge drawn from the secondary settlement tank of a small WWTP for domestic sewage. After the disintegration stage, the treated sludge was returned to the biological reactor. Three different percentages (50, 75 and 100%) of the return sludge flow rate were subjected to disintegration and the effects on the sludge production and the WWTP operation efficiency evaluated. The long-term observations showed that the electro-kinetic disintegration was able to drastically reduce the amount of biological sludge produced by the plant, without affecting its treatment efficiency. The highest reduction was achieved when 100% return sludge flow rate was subjected to the disintegration process. The reduced sludge production gave rise to a considerable net cost saving for the company which manages the plant.

Ecohydrological Design of small hydropower plants: assessment of environmental flows

International Nuclear Information System (INIS)

Diez H, Juan M; Olmeda S, Sergio

2008-01-01

The small hydroelectric energy has contributed substantially to the progress of the life standards in the world by means of a technology with a relatively low environmental impact. The Small Hydroelectric Plant (SHP) is the convenient type of hydro energetic facility for Colombia, reason why it predictably will play a capital role in the exploitation of its excellent potential during this decade. The regulatory guidelines for the SHP re licensing enforce hydrological design criteria that incorporate the ecological requirements of discharge in the fluvial reaches affected by flow derivations. The Instream Flow (IF) should be considered as an ecological restriction to the hydroelectric use, which can be satisfactorily set with reliable approaches. This work shows the basic typology of IF assessment methods, describing the reputed Instream Flow Incremental Methodology (IFIM) with a case study of SHP re licensing. It also demonstrates the possibility of harmonize the hydroelectric operation with the maintenance of an acceptable ecological condition, preserving some IF that can be assessed with the IFIM analytic frame. The new eco hydrological methods for IF setting facilitate SHP that are profitable and defensible in environmental terms.

Life cycle assessment of a small-scale anaerobic digestion plant from cattle waste

International Nuclear Information System (INIS)

Mezzullo, William G.; McManus, Marcelle C.; Hammond, Geoff P.

2013-01-01

Highlights: ► Emissions from plant manufacture contributed little towards the lifecycle impacts. ► The use phase of the AD plant could have significant impacts. ► Production of biogas and fertiliser created significant impacts. ► The consequential displacement of kerosene showed a net-benefit. ► The study concluded that it is essential to cover the digestate storage tank. -- Abstract: This paper outlines the results of a comprehensive life cycle study of the production of energy, in the form of biogas, using a small scale farm based cattle waste fed anaerobic digestion (AD) plant. The life cycle assessment (LCA) shows that in terms of environmental and energy impact the plant manufacture contributes very little to the whole life cycle impacts. The results show that compared with alternative energy supply the production and use of biogas is beneficial in terms of greenhouse gases and fossil fuel use. This is mainly due to the replacement of the alternative, kerosene, and from fertiliser production from the AD process. However, these benefits come at a cost to ecosystem health and the production of respiratory inorganics. These were found to be a result of ammonia emissions during the production phase of the biogas. These damages can be significantly reduced if further emission control measures are undertaken.

Plant-soil feedbacks: role of plant functional group and plant traits

NARCIS (Netherlands)

Cortois, R.; Schröder-Georgi, T.; Weigelt, A.; van der Putten, W.H.; De Deyn, G.B.

2016-01-01

Plant-soil feedback (PSF), plant trait and functional group concepts advanced our understanding of plant community dynamics, but how they are interlinked is poorly known. To test how plant functional groups (FGs: graminoids, small herbs, tall herbs, legumes) and plant traits relate to PSF, we grew

Isoelectric focusing of small non-covalent metal species from plants.

Science.gov (United States)

Köster, Jessica; Hayen, Heiko; von Wirén, Nicolaus; Weber, Günther

2011-03-01

IEF is known as a powerful electrophoretic separation technique for amphoteric molecules, in particular for proteins. The objective of the present work is to prove the suitability of IEF also for the separation of small, non-covalent metal species. Investigations are performed with copper-glutathione complexes, with the synthetic ligand ethylenediamine-N,N'-bis(o-hydroxyphenyl)acetic acid (EDDHA) and respective metal complexes (Fe, Ga, Al, Ni, Zn), and with the phytosiderophore 2'-deoxymugineic acid (DMA) and its ferric complex. It is shown that ethylenediamine-N,N'-bis(o-hydroxyphenyl)acetic acid and DMA species are stable during preparative scale IEF, whereas copper-glutathione dissociates considerably. It is also shown that preparative scale IEF can be applied successfully to isolate ferric DMA from real plant samples, and that multidimensional separations are possible by combining preparative scale IEF with subsequent HPLC-MS analysis. Focusing of free ligands and respective metal complexes with di- and trivalent metals results in different pIs, but CIEF is usually needed for a reliable estimation of pI values. Limitations of the proposed methods (preparative IEF and CIEF) and consequences of the results with respect to metal speciation in plants are discussed. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Evaluation of Suitability of Selected Set of Coal Plant Sites for Repowering with Small Modular Reactors

Energy Technology Data Exchange (ETDEWEB)

Belles, Randy [ORNL; Copinger, Donald A [ORNL; Mays, Gary T [ORNL; Omitaomu, Olufemi A [ORNL; Poore III, Willis P [ORNL

2013-03-01

This report summarizes the approach that ORNL developed for screening a sample set of small coal stations for possible repowering with SMRs; the methodology employed, including spatial modeling; and initial results for these sample plants. The objective in conducting this type of siting evaluation is to demonstrate the capability to characterize specific sample coal plant sites to identify any particular issues associated with repowering existing coal stations with SMRs using OR-SAGE; it is not intended to be a definitive assessment per se as to the absolute suitability of any particular site.

Do Small Canopy Gaps Created by Japanese Black Bears Facilitate Fruiting of Fleshy-Fruited Plants?

Directory of Open Access Journals (Sweden)

Kazuaki Takahashi

Full Text Available Japanese black bears often break branches when climbing trees and feeding on fruit in canopies, thereby creating small canopy gaps. However, the role of black bear-created canopy gaps has not been evaluated in the context of multiple forest dynamics. Our hypothesis was that small canopy gaps created by black bears improve light conditions, which facilitates fruiting of adult fleshy-fruited plants located beneath the gaps, and also that this chain interaction depends on interactions among the size of gaps, improved light conditions, forest layers, and life form of plants. The rPPFD, size of black bear-created canopy gaps, and fruiting/non-fruiting of fleshy-fruited plants were investigated in five forest layers beneath black-bear-created canopy gaps and closed canopies of Mongolian oak (Quercus crispula. We found that light conditions improved beneath black bear-disturbed trees with canopy gaps of large size, and the effect of improvement of light conditions was reduced with descending forest layers. Fruiting of fleshy-fruited plants, especially woody lianas and trees, was facilitated by the improvement of light conditions accompanied by an increase in the size of black-bear-created gaps. Data from this study revealed that canopy disturbance by black bears was key for improving light conditions and accelerating fruiting of fleshy-fruited trees and woody lianas in the canopy layers in particular. Therefore, our hypothesis was mostly supported. Our results provide evidence that Japanese black bears have high potential as ecosystem engineers that increase the availability of resources (light and fruit in this study to other species by causing physical state changes in biotic materials (branches of Q. crispula in this study.

Do Small Canopy Gaps Created by Japanese Black Bears Facilitate Fruiting of Fleshy-Fruited Plants?

Science.gov (United States)

Takahashi, Kazuaki; Takahashi, Kaori; Washitani, Izumi

2015-01-01

Japanese black bears often break branches when climbing trees and feeding on fruit in canopies, thereby creating small canopy gaps. However, the role of black bear-created canopy gaps has not been evaluated in the context of multiple forest dynamics. Our hypothesis was that small canopy gaps created by black bears improve light conditions, which facilitates fruiting of adult fleshy-fruited plants located beneath the gaps, and also that this chain interaction depends on interactions among the size of gaps, improved light conditions, forest layers, and life form of plants. The rPPFD, size of black bear-created canopy gaps, and fruiting/non-fruiting of fleshy-fruited plants were investigated in five forest layers beneath black-bear-created canopy gaps and closed canopies of Mongolian oak (Quercus crispula). We found that light conditions improved beneath black bear-disturbed trees with canopy gaps of large size, and the effect of improvement of light conditions was reduced with descending forest layers. Fruiting of fleshy-fruited plants, especially woody lianas and trees, was facilitated by the improvement of light conditions accompanied by an increase in the size of black-bear-created gaps. Data from this study revealed that canopy disturbance by black bears was key for improving light conditions and accelerating fruiting of fleshy-fruited trees and woody lianas in the canopy layers in particular. Therefore, our hypothesis was mostly supported. Our results provide evidence that Japanese black bears have high potential as ecosystem engineers that increase the availability of resources (light and fruit in this study) to other species by causing physical state changes in biotic materials (branches of Q. crispula in this study).

Energy options and the role of coal: an integrated approach

Energy Technology Data Exchange (ETDEWEB)

Isaacs, E. [Alberta Energy Research Institute, Edmonton, AB (Canada)

2006-07-01

Considers energy goals and options with particular regard to providing affordable energy to Canada. Gasification of coal and carbon to provide a reliable source of clean power and heat to the oil sand industry and for feedstocks for the production of fertilizer, methanol, petrochemicals, and ultra-clean fuels is examined. The layout for integrated gasification polygeneration with carbon feed and plans for Canada's first commercial gasification plant (the Nexen Long Lake Project) are shown in diagrams. Progress in coal gasification at a clean coal Luscar/Sherritt pilot plant is outlined. Clean coal technology is part of a strategy to provide integration across energy systems, generate value for all hydrocarbon resources, and minimize emissions. 15 figs., 2 tabs.

Safety issues and their ranking for 'small series' WWER-1000 nuclear power plants. A publication of the extrabudgetary programme on the safety of WWER and RBMK nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-09-01

This report presents the safety issues in 'small series' WWER-1000 nuclear power plants (NPPs). Safety issues are deviations from current recognized safety practices in design and operation judged to be safety significant by their impact on the plants' defence in depth. This report is intended to serve as reference for the development of plant specific safety improvement programmes and for the evaluation of measures proposed and/or implemented. The identification of safety issues is based on safety studies conducted by the operators of 'small series' WWER-1000 units and by organizations dealing with these reactors, on findings of IAEA safety missions to 'small series' WWER-1000 plants in South Ukraine, at Novovoronezh and Kalinin, and on information obtained from specialists from various countries during an IAEA consultants meeting, 8-12 September 1997 in Vienna, within the framework of the Extra budgetary Programme on the Safety of WWER and RBMK NPPs. Safety issues are first presented according to their impact on the main safety functions and are then described individually. The safety issues are characterized by issue title and specified by issue clarification. Safety issues connected with plant design are followed by the ranking of the issue and ranking justification. Altogether 85 safety issues have been identified, 12 of which are in Category III (defence in depth is insufficient, immediate corrective action is necessary), 38 in Category 11 (defence in depth is degraded, action is needed to resolve the issue) and 22 in Category I (departure from international practices, to be addressed as part of actions to resolve higher priority issues). In the case of operational safety issues (13 safety issues) no ranking is provided as the available material was considered insufficient. For each safety issue, comments and recommendations are made by the IAEA; the status of corresponding measures to improve safety implemented or planned at each site are presented in the

Safety issues and their ranking for 'small series' WWER-1000 nuclear power plants. A publication of the extrabudgetary programme on the safety of WWER and RBMK nuclear power plants

International Nuclear Information System (INIS)

2000-09-01

This report presents the safety issues in 'small series' WWER-1000 nuclear power plants (NPPs). Safety issues are deviations from current recognized safety practices in design and operation judged to be safety significant by their impact on the plants' defence in depth. This report is intended to serve as reference for the development of plant specific safety improvement programmes and for the evaluation of measures proposed and/or implemented. The identification of safety issues is based on safety studies conducted by the operators of 'small series' WWER-1000 units and by organizations dealing with these reactors, on findings of IAEA safety missions to 'small series' WWER-1000 plants in South Ukraine, at Novovoronezh and Kalinin, and on information obtained from specialists from various countries during an IAEA consultants meeting, 8-12 September 1997 in Vienna, within the framework of the Extra budgetary Programme on the Safety of WWER and RBMK NPPs. Safety issues are first presented according to their impact on the main safety functions and are then described individually. The safety issues are characterized by issue title and specified by issue clarification. Safety issues connected with plant design are followed by the ranking of the issue and ranking justification. Altogether 85 safety issues have been identified, 12 of which are in Category III (defence in depth is insufficient, immediate corrective action is necessary), 38 in Category 11 (defence in depth is degraded, action is needed to resolve the issue) and 22 in Category I (departure from international practices, to be addressed as part of actions to resolve higher priority issues). In the case of operational safety issues (13 safety issues) no ranking is provided as the available material was considered insufficient. For each safety issue, comments and recommendations are made by the IAEA; the status of corresponding measures to improve safety implemented or planned at each site are presented in the

Systemic delivery of siRNA in pumpkin by a plant PHLOEM SMALL RNA-BINDING PROTEIN 1-ribonucleoprotein complex.

Science.gov (United States)

Ham, Byung-Kook; Li, Gang; Jia, Weitao; Leary, Julie A; Lucas, William J

2014-11-01

In plants, the vascular system, specifically the phloem, functions in delivery of small RNA (sRNA) to exert epigenetic control over developmental and defense-related processes. Although the importance of systemic sRNA delivery has been established, information is currently lacking concerning the nature of the protein machinery involved in this process. Here, we show that a PHLOEM SMALL-RNA BINDING PROTEIN 1 (PSRP1) serves as the basis for formation of an sRNA ribonucleoprotein complex (sRNPC) that delivers sRNA (primarily 24 nt) to sink organs. Assembly of this complex is facilitated through PSRP1 phosphorylation by a phloem-localized protein kinase, PSRPK1. During long-distance transport, PSRP1-sRNPC is stable against phloem phosphatase activity. Within target tissues, phosphatase activity results in disassembly of PSRP1-sRNPC, a process that is probably required for unloading cargo sRNA into surrounding cells. These findings provide an insight into the mechanism involved in delivery of sRNA associated with systemic gene silencing in plants. © 2014 The Authors The Plant Journal © 2014 John Wiley & Sons Ltd.

Implementation strategy for small CHP-plants in a competitive market: the case of Lithuania

International Nuclear Information System (INIS)

Lund, H.; Siupsinskas, G.; Martinaitis, V.

2005-01-01

Within five years from now, Lithuania is going to close down Ignalina, the only nuclear-power plant in the country. Since Ignalina generates more than 75% of the Lithuanian electricity production, new generation capacities are needed. Traditional steam-turbines, fuelled with fossil fuels, would mean further imports of fuel as well as a rise in CO 2 emissions. At the same time, several small district-heating companies one suffering from high heating-prices. Typically, the price in small towns is 20-50% higher than the price in large urban areas. Consequently, alternative strategies should be considered. This article analyses the conditions for one such strategy, namely the replacement of boilers in the existing district-heating supplies with combined heat-and-power production (CHP). Compared with new power stations, fuel can be saved and CO 2 -emissions reduced. Also this strategy can be used to level the difference between low heating prices in the large urban areas and high prices in small towns and villages. (Author)

ANTIBACTERIAL POTENTIAL OF NATIVE PLANTS FROM THE CAATINGA BIOME AGAINST Staphylococcus spp. ISOLATES FROM SMALL RUMINANTS WITH MASTITIS

OpenAIRE

PEIXOTO, RODOLFO DE MORAES; SILVA, WELLINGTON ERASMO LIMA E; ALMEIDA, JACKSON ROBERTO GUEDES SILVA; BRANCO, ALEXSANDRO; COSTA, MATEUS MATIUZZI DA

2016-01-01

ABSTRACT The aim of the present study is to assess the antibacterial potential of plants from the Caatinga biome of the semi-arid region of Pernambuco, against Staphylococcus spp. isolates from cases of subclinical mastitis in small ruminants, such as goats and ewes. Ethanolic extracts of the following plants from the Caatinga biome were used: Encholirium spectabile Mart., Bromelia laciniosa Mart., Neoglaziovia variegata Mez., Amburana cearensis (Fr. Allem.) A. C. Smith, Hymenaea martiana Hay...

Preliminary analyses on hydrogen diffusion through small break of thermo-chemical IS process hydrogen plant

International Nuclear Information System (INIS)

Somolova, Marketa; Terada, Atsuhiko; Takegami, Hiroaki; Iwatsuki, Jin

2008-12-01

Japan Atomic Energy Agency has been conducting a conceptual design study of nuclear hydrogen demonstration plant, that is, a thermal-chemical IS process hydrogen plant coupled with the High temperature Engineering Test Reactor (HTTR-IS), which will be planed to produce a large amount of hydrogen up to 1000m 3 /h. As part of the conceptual design work of the HTTR-IS system, preliminary analyses on small break of a hydrogen pipeline in the IS process hydrogen plant was carried out as a first step of the safety analyses. This report presents analytical results of hydrogen diffusion behaviors predicted with a CFD code, in which a diffusion model focused on the turbulent Schmidt number was incorporated. By modifying diffusion model, especially a constant accompanying the turbulent Schmidt number in the diffusion term, analytical results was made agreed well with the experimental results. (author)

Watermill and Small-Scale Hydroelectric Power Plant Landscapes Assessed According to Ecological Aspects

Directory of Open Access Journals (Sweden)

Lilita Lazdāne

2013-10-01

Full Text Available Research of watermill and small-scale hydroelectric power plant (HPP landscapes in Latvia according to ecological aspects is a part of a more complex research. The aim of this research is to examine the existing situation of watermill and small-scale HPP landscapes in Latvia by applying the ecological assessment criteria, and then try to formulate a definition of common tendencies of the landscape character. This paper provides a landscape inventory matrix for research in the field stu­dies of landscape identification at the local planning level. The duration of the research was from 2010 to 2012. The research includes 42 territories starting with the three most densely developed areas in Latvia: in Latgale, Kurzeme and Vidzeme uplands distribution ranges. The research results reflect tendencies of the landscape features assessed according to the previously developed criteria of ecological aspects.

Results of small break LOCA analysis for Kuosheng nuclear power plant using the RELAP5YA computer code

International Nuclear Information System (INIS)

Wang, L.C.; Jeng, S.C.; Chung, N.M.

2004-01-01

One lesson learned from the Three Mile Island (TMI) accident was the analysis methods used by Nuclear Steam Supply System (NSSS) vendors and/or nuclear fuel suppliers for small break Loss Of Coolant Accident (LOCA) analysis for compliance with appendix K to 10CFR50 should be revised, documented and submitted for USNRC approval and the plant-specific calculations using NRC-approved models for small-break LOCA to show compliance with 10CFR50.46 should be submitted for NRC approval. A study by Taiwan Power Company (TPC) under the guidance of Yankee Atomic Electric Company (YAEC) has been undertaken to perform this analysis for Kuosheng nuclear power plant. This paper presents the results of the analysis that are useful in satisfying the same requirements of the Republic Of China Atomic Energy Commission (ROCAEC). (author)

Design and static simulation of secondary loop of small PWR nuclear power plants

International Nuclear Information System (INIS)

Martin Lopez, L.A.N.

1989-01-01

A computer program that has been developed with the purpose of making easier the decisions concerning the design of the secondary loop of small PWR nuclear power plants through numerical experiments of low running costs and short time is presented. Initially, the first part of the computer program is described. It aims to preliminarily design several major components of the secondary circuit from user-defined design conditions. Next, the second part of the computer program is presented. It simulates the steady state operation at part-load conditions of the preliminary design of the plant by generating and solving systems of simultaneous nonlinear algebraic equations, their number varying from 17 to 107. The computer program has been tested for several application cases. The program results are discussed in the last part of the work, along with several aspects to be added to the program in future works. (author)

Economic analysis of a small-sized combined heat and power plant using forest biomass in the Republic of Korea

Science.gov (United States)

Yeongwan Seo; Han-Sup Han; Edward M. (Ted) Bilek; Jungkee Choi; Dusong Cha; Jungsoo Lee

2017-01-01

Economic analysis was conducted on the feasibility of operating a small-sized (500kW/hour) gasification power plant producing heat and electricity in a rural town surrounded by forests in the Republic of Korea. Cost factors that were considered over the plant’s 20-year life included wood procurement, a wood grab loader, a chipper, a chip dryer, a gasifier, a generator...

Potential Markets for Small Reactors. Annex XI

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-12-15

The electricity cost of a small power generation plant is generally higher than that of a large scale power plant due to economies of scale. In order to survey the market for small nuclear power plants, the competitive object is not a large scale power plant but a small fossil fuel power generation plant. Large scale power generation plants are not required in all countries and regions of the world. There are many regions where the electricity cost is high because of the cost of fuel transport to remote places. Medium or small power generation plants could turn out to also be preferable from the viewpoints of electrical power demand and distribution cost. For example, the electricity costs in many small cities or towns of the Alaskan and Hawaiian Islands are higher than on the mainland. The electricity costs in the two peninsulas (Baja California and Yucatan) in Mexico are high because, owing to the limited power demand in these regions, small and medium sized fossil fuel power generation plants have been installed there, and the costs of fuel, fuel transport and power transmission appear to be relatively high. Owing to such situations, a market for small and medium sized nuclear reactors exists, and there are certain regions and areas in the world where such reactors can compete with the alternatives.

A novel conceptual design of parallel nitrogen expansion liquefaction process for small-scale LNG (liquefied natural gas) plant in skid-mount packages

International Nuclear Information System (INIS)

He, Tianbiao; Ju, Yonglin

2014-01-01

The utilization of unconventional natural gas is still a great challenge for China due to its distribution locations and small reserves. Thus, liquefying the unconventional natural gas by using small-scale LNG plant in skid-mount packages is a good choice with great economic benefits. A novel conceptual design of parallel nitrogen expansion liquefaction process for small-scale plant in skid-mount packages has been proposed. It first designs a process configuration. Then, thermodynamic analysis of the process is conducted. Next, an optimization model with genetic algorithm method is developed to optimize the process. Finally, the flexibilities of the process are tested by two different feed gases. In conclusion, the proposed parallel nitrogen expansion liquefaction process can be used in small-scale LNG plant in skid-mount packages with high exergy efficiency and great economic benefits. - Highlights: • A novel design of parallel nitrogen expansion liquefaction process is proposed. • Genetic algorithm is applied to optimize the novel process. • The unit energy consumption of optimized process is 0.5163 kWh/Nm 3 . • The exergy efficiency of the optimized case is 0.3683. • The novel process has a good flexibility for different feed gas conditions

Networking by small-molecule hormones in plant immunity

NARCIS (Netherlands)

Pieterse, C.M.J.; Leon Reyes, H.A.; Ent, S. van der; Wees, A.C.M. van

2009-01-01

Plants live in complex environments in which they intimately interact with a broad range of microbial pathogens with different lifestyles and infection strategies. The evolutionary arms race between plants and their attackers provided plants with a highly sophisticated defense system that, like the

Networking by small-molecule hormones in plant immunity

NARCIS (Netherlands)

Pieterse, C.M.J.; Leon Reyes, H.A.; Does, D. van der; Verhage, A.; Koornneef, A.; Pelt, J.A. van; Wees, S.C.M. van

2012-01-01

Plants live in complex environments in which they intimately interact with a broad range of microbial pathogens and insect herbivores with different lifestyles and infection or feeding strategies. The evolutionary arms race between plants and their attackers provided plants with a sophisticated

Small RNAs were involved in homozygous state-associated silencing of a marker gene (Neomycin phosphotransferase II: nptII) in transgenic tomato plants.

Science.gov (United States)

Deng, Lei; Pan, Yu; Chen, Xuqing; Chen, Guoping; Hu, Zongli

2013-07-01

Homozygous state-associated co-suppression is not a very common phenomenon. In our experiments, two transgenic plants 3A29 and 1195A were constructed by being transformed with the constructs pBIN-353A and pBIN119A containing nptII gene as a marker respectively. The homozygous progeny from these two independent transgenic lines 3A29 and 1195A, displayed kanamycin-sensitivity and produced a short main root without any lateral roots as untransformed control (wild-type) seedlings when germinated on kanamycin media. For the seedlings derived from putative hemizygous plants, the percentage of the seedlings showing normal growth on kanamycin media was about 50% and lower than the expected percentage (75%). Southern analysis of the genomic DNA confirmed that the homozygous and hemizygous plants derived from the same lines contained the same multiple nptII transgenes, which were located on the same site of chromosome. Northern analysis suggested that the marker nptII gene was expressed in the primary and the hemizygous transformants, but it was silenced in the homozygous transgenic plants. Further Northern analysis indicated that antisense and sense small nptII-derived RNAs were present in the transgenic plants and the blotting signal of nptII-derived small RNA was much higher in the homozygous transgenic plants than that of hemizygous transgenic plants. Additionally, read-through transcripts from the TRAMP gene to the nptII gene were detected. These results suggest that the read-through transcripts may be involved in homozygous state-associated silencing of the nptII transgene in transgenic tomato plants and a certain threshold level of the nptII-derived small RNAs is required for the homozygous state-associated co-suppression of the nptII transgene. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

Profile of small interfering RNAs from cotton plants infected with the polerovirus Cotton leafroll dwarf virus

Directory of Open Access Journals (Sweden)

Schrago Carlos EG

2011-08-01

Full Text Available Abstract Background In response to infection, viral genomes are processed by Dicer-like (DCL ribonuclease proteins into viral small RNAs (vsRNAs of discrete sizes. vsRNAs are then used as guides for silencing the viral genome. The profile of vsRNAs produced during the infection process has been extensively studied for some groups of viruses. However, nothing is known about the vsRNAs produced during infections of members of the economically important family Luteoviridae, a group of phloem-restricted viruses. Here, we report the characterization of a population of vsRNAs from cotton plants infected with Cotton leafroll dwarf virus (CLRDV, a member of the genus Polerovirus, family Luteoviridae. Results Deep sequencing of small RNAs (sRNAs from leaves of CLRDV-infected cotton plants revealed that the vsRNAs were 21- to 24-nucleotides (nt long and that their sequences matched the viral genome, with higher frequencies of matches in the 3- region. There were equivalent amounts of sense and antisense vsRNAs, and the 22-nt class of small RNAs was predominant. During infection, cotton Dcl transcripts appeared to be up-regulated, while Dcl2 appeared to be down-regulated. Conclusions This is the first report on the profile of sRNAs in a plant infected with a virus from the family Luteoviridae. Our sequence data strongly suggest that virus-derived double-stranded RNA functions as one of the main precursors of vsRNAs. Judging by the profiled size classes, all cotton DCLs might be working to silence the virus. The possible causes for the unexpectedly high accumulation of 22-nt vsRNAs are discussed. CLRDV is the causal agent of Cotton blue disease, which occurs worldwide. Our results are an important contribution for understanding the molecular mechanisms involved in this and related diseases.

Profile of small interfering RNAs from cotton plants infected with the polerovirus Cotton leafroll dwarf virus.

Science.gov (United States)

Silva, Tatiane F; Romanel, Elisson A C; Andrade, Roberto R S; Farinelli, Laurent; Østerås, Magne; Deluen, Cécile; Corrêa, Régis L; Schrago, Carlos E G; Vaslin, Maite F S

2011-08-24

In response to infection, viral genomes are processed by Dicer-like (DCL) ribonuclease proteins into viral small RNAs (vsRNAs) of discrete sizes. vsRNAs are then used as guides for silencing the viral genome. The profile of vsRNAs produced during the infection process has been extensively studied for some groups of viruses. However, nothing is known about the vsRNAs produced during infections of members of the economically important family Luteoviridae, a group of phloem-restricted viruses. Here, we report the characterization of a population of vsRNAs from cotton plants infected with Cotton leafroll dwarf virus (CLRDV), a member of the genus Polerovirus, family Luteoviridae. Deep sequencing of small RNAs (sRNAs) from leaves of CLRDV-infected cotton plants revealed that the vsRNAs were 21- to 24-nucleotides (nt) long and that their sequences matched the viral genome, with higher frequencies of matches in the 3- region. There were equivalent amounts of sense and antisense vsRNAs, and the 22-nt class of small RNAs was predominant. During infection, cotton Dcl transcripts appeared to be up-regulated, while Dcl2 appeared to be down-regulated. This is the first report on the profile of sRNAs in a plant infected with a virus from the family Luteoviridae. Our sequence data strongly suggest that virus-derived double-stranded RNA functions as one of the main precursors of vsRNAs. Judging by the profiled size classes, all cotton DCLs might be working to silence the virus. The possible causes for the unexpectedly high accumulation of 22-nt vsRNAs are discussed. CLRDV is the causal agent of Cotton blue disease, which occurs worldwide. Our results are an important contribution for understanding the molecular mechanisms involved in this and related diseases.

Fuzzy logic and its possibility using in automation of small-scale hydroelectric power plants regulation

International Nuclear Information System (INIS)

Puskajler, J.

2004-01-01

The paper explains how can computer understand and process inaccurate (indefinite) information. It is processing of terms like e.g. 'around in the middle of month' or 'not too big'. Fuzzy logic, fuzzy sets, operations with them, fuzzy rules and using of linguistics variables are explained. The possibilities of application of fuzzy systems in automation of regulation of small-scale hydro power plants are discussed. (author)

Advances in small zero-leak valves point to better nuclear power-plant reliability

Energy Technology Data Exchange (ETDEWEB)

Eacott, K B; Kin, J C; Hotta, Y [Dresser Japan, Ltd.

1978-04-01

In the selection of small valves less than two inches used for nuclear power plants, sufficient consideration must be given to the reliability to radioactive material, the easy operability, and the significant function, especially zero leak. These valves are classified into bellows and diaphragm seal types which must satisfy zero leak, 4000 cycles life test and good maintainability. Welded bellows, formed bellows, and metal diaphragms are actually used for these requirements. The construction of these types are shown. The requirements and principal specifications for these small valves are explained, and some examples are given. These zero leak valves are installed in reactor coolant loop system, borated water from B. A. system, pressurizer instrument system, containment spray system, high head system and off gas system for PWRS, and main steam line system, diesel generator cooling water system, re-circulation system, clean up water system, etc. for BWRS.

Computational investigation of small RNAs in the establishment of root nodules and arbuscular mycorrhiza in leguminous plants.

Science.gov (United States)

Jin, Danfeng; Meng, Xianwen; Wang, Yue; Wang, Jingjing; Zhao, Yuhua; Chen, Ming

2018-01-03

Many small RNAs have been confirmed to play important roles in the development of root nodules and arbuscular mycorrhiza. In this study, we carried out the identification of certain small RNAs in leguminous plants (Medicago truncatula, soybean, peanut and common bean), such as miRNAs, tRFs and srRNAs, as well as the computational investigation of their regulations. Thirty miRNAs were predicted to be involved in establishing root nodules and mycorrhiza, and 12 of them were novel in common bean and peanut. The generation of tRFs in M. truncatula was not associated with tRNA gene frequencies and codon usage. Six tRFs exhibited different expressions in mycorrhiza and root nodules. Moreover, srRNA 5.8S in M. truncatula was generated from the regions with relatively low conservation at the rRNA 3' terminal. The protein-protein interactions between the proteins encoded by the target genes of miRNAs, tRFs and srRNAs were computed. The regulation of these three types of sRNAs in the symbiosis between leguminous plants and microorganisms is not a single regulation of certain signaling or metabolic pathways but a global regulation for the plants to own growth or specific events in symbiosis.

Intensive land use drives small-scale homogenization of plant- and leafhopper communities and promotes generalists.

Science.gov (United States)

Chisté, Melanie N; Mody, Karsten; Kunz, Gernot; Gunczy, Johanna; Blüthgen, Nico

2018-02-01

The current biodiversity decline through anthropogenic land-use not only involves local species losses, but also homogenization of communities, with a few generalist species benefitting most from human activities. Most studies assessed community heterogeneity (β-diversity) on larger scales by comparing different sites, but little is known about impacts on β-diversity within each site, which is relevant for understanding variation in the level of α-diversity, the small-scale distribution of species and associated habitat heterogeneity. To obtain our dataset with 36,899 individuals out of 117 different plant- and leafhopper (Auchenorrhyncha) species, we sampled communities of 140 managed grassland sites across Germany by quantitative vacuum suction of five 1 m 2 plots on each site. Sites differed in land-use intensity as characterized by intensity of fertilization, mowing and grazing. Our results demonstrate a significant within-site homogenization of plant- and leafhopper communities with increasing land-use intensity. Correspondingly, density (- 78%) and γ-diversity (- 35%) declined, particularly with fertilization and mowing intensity. More than 34% of plant- and leafhopper species were significant losers and only 6% were winners of high land-use intensity, with abundant and widespread species being less affected. Increasing land-use intensity adversely affected dietary specialists and promoted generalist species. Our study emphasizes considerable, multifaceted effects of land-use intensification on species loss, with a few dominant generalists winning, and an emerging trend towards more homogenized assemblages. By demonstrating homogenization for the first time within sites, our study highlights that anthropogenic influences on biodiversity even occur on small scales.

Who needs a small reactor?

International Nuclear Information System (INIS)

Wood, Janet.

1991-01-01

The opportunities and problems facing small reactors were debated at the Delhi seminar. It was established that these were markets where small reactors, producing heat as well as electricity, might be of use. Small combined heat and power reactors would be more useful in district heating than would large reactors, as their optimum heat production is in line with current district heating schemes. Most process heat requirements are below 900 o C and so may be provided by small nuclear plants. Several areas in electricity supply where small and medium sized reactors could find a market were also identified. Despite good reasons for favouring nuclear plants in these markets, such as no production of carbon dioxide, no need to use expensive oil or other scarce fossil fuels and flexibility, these are, however, disincentives to potential buyers. While serial production would decrease plant costs, the lead plants would bear heavy financial risks. Currently too many options in plant design make it difficult to present the advantages of small reactor technology. Siting reactors near centres of population would be problematical. The disposal of spent fuel and radioactive wastes would create problems in developing or non-nuclear countries. Over and above all these problems, however, was that of public acceptance. Some ways of overcoming these disincentives were discussed. (author)

New markets for small-scale hydro

International Nuclear Information System (INIS)

Maurer, E.A.

1997-01-01

The market for small and medium sized hydro-electric power plant is more attractive than ever. The boom in Europe has increasingly spread to the emerging countries, and here too small hydro plays an important ecological role. In addition to new plant rehabilitation of 'historical' plant is now a major factor. The last few years have seen a market shift from single machine components to complete plant and systems, requiring a strategy re-think on the part of larger companies. Following the influx of private capital into the power industry, business conditions have also undergone a thorough transformation. In place of 'fast money', hydro power offers the prospect of earning longer-term, sustainable money'. The term small-scale hydro-electric power (or simply 'small hydro') is used slightly differently depending on the country and market. Here, it is used to denote plant with turbines up to 10 MW. (Author)

Westinghouse Small Modular Reactor balance of plant and supporting systems design

Energy Technology Data Exchange (ETDEWEB)

Memmott, M. J.; Stansbury, C.; Taylor, C. [Westinghouse Electric Company LLC, 600 Cranberry Woods Drive, Cranberry Twp. PA 16066 (United States)

2012-07-01

The Westinghouse Small Modular Reactor (SMR) is an 800 MWt (>225 MWe) integral pressurized water reactor (iPWR), in which all of the components typically associated with the nuclear steam supply system (NSSS) of a nuclear power plant are incorporated within a single reactor pressure vessel. This paper is the second in a series of four papers which describe the design and functionality of the Westinghouse SMR. It focuses, in particular, upon the supporting systems and the balance of plant (BOP) designs of the Westinghouse SMR. Several Westinghouse SMR systems are classified as safety, and are critical to the safe operation of the Westinghouse SMR. These include the protection and monitoring system (PMS), the passive core cooling system (PXS), and the spent fuel cooling system (SFS) including pools, valves, and piping. The Westinghouse SMR safety related systems include the instrumentation and controls (I and C) as well as redundant and physically separated safety trains with batteries, electrical systems, and switch gears. Several other incorporated systems are non-safety related, but provide functions for plant operations including defense-in-depth functions. These include the chemical volume control system (CVS), heating, ventilation and cooling (HVAC) systems, component cooling water system (CCS), normal residual heat removal system (RNS) and service water system (SWS). The integrated performance of the safety-related and non-safety related systems ensures the safe and efficient operation of the Westinghouse SMR through various conditions and transients. The turbine island consists of the turbine, electric generator, feedwater and steam systems, moisture separation systems, and the condensers. The BOP is designed to minimize assembly time, shipping challenges, and on-site testing requirements for all structures, systems, and components. (authors)

Westinghouse Small Modular Reactor balance of plant and supporting systems design

International Nuclear Information System (INIS)

Memmott, M. J.; Stansbury, C.; Taylor, C.

2012-01-01

The Westinghouse Small Modular Reactor (SMR) is an 800 MWt (>225 MWe) integral pressurized water reactor (iPWR), in which all of the components typically associated with the nuclear steam supply system (NSSS) of a nuclear power plant are incorporated within a single reactor pressure vessel. This paper is the second in a series of four papers which describe the design and functionality of the Westinghouse SMR. It focuses, in particular, upon the supporting systems and the balance of plant (BOP) designs of the Westinghouse SMR. Several Westinghouse SMR systems are classified as safety, and are critical to the safe operation of the Westinghouse SMR. These include the protection and monitoring system (PMS), the passive core cooling system (PXS), and the spent fuel cooling system (SFS) including pools, valves, and piping. The Westinghouse SMR safety related systems include the instrumentation and controls (I and C) as well as redundant and physically separated safety trains with batteries, electrical systems, and switch gears. Several other incorporated systems are non-safety related, but provide functions for plant operations including defense-in-depth functions. These include the chemical volume control system (CVS), heating, ventilation and cooling (HVAC) systems, component cooling water system (CCS), normal residual heat removal system (RNS) and service water system (SWS). The integrated performance of the safety-related and non-safety related systems ensures the safe and efficient operation of the Westinghouse SMR through various conditions and transients. The turbine island consists of the turbine, electric generator, feedwater and steam systems, moisture separation systems, and the condensers. The BOP is designed to minimize assembly time, shipping challenges, and on-site testing requirements for all structures, systems, and components. (authors)

DAILY SCHEDULING OF SMALL HYDRO POWER PLANTS DISPATCH WITH MODIFIED PARTICLES SWARM OPTIMIZATION

Directory of Open Access Journals (Sweden)

Sinvaldo Rodrigues Moreno

2015-04-01

Full Text Available This paper presents a new approach for short-term hydro power scheduling of reservoirs using an algorithm-based Particle Swarm Optimization (PSO. PSO is a population-based algorithm designed to find good solutions to optimization problems, its characteristics have encouraged its adoption to tackle a variety of problems in different fields. In this paper the authors consider an optimization problem related to a daily scheduling of small hydro power dispatch. The goal is construct a feasible solution that maximize the cascade electricity production, following the environmental constraints and water balance. The paper proposes an improved Particle Swarm Optimization (PSO algorithm, which takes advantage of simplicity and facility of implementation. The algorithm was successfully applied to the optimization of the daily schedule strategies of small hydro power plants, considering maximum water utilization and all constraints related to simultaneous water uses. Extensive computational tests and comparisons with other heuristics methods showed the effectiveness of the proposed approach.

Multi-stage-flash desalination plants of relative small performance with integrated pressurized water reactors as a nuclear heat source

International Nuclear Information System (INIS)

Petersen, G.; Peltzer, M.

1977-01-01

In the Krupp-GKSS joint study MINIPLEX the requirements for seawater-desalination plants with a performance in the range of 10 000 to 80 000 m 3 distillate per day heated by a nuclear reactor are investigated. The reactor concept is similar to the Integrated Pressurized Water Reactor (IPWR) of the nuclear ship OTTO HAHN. The design study shows that IPWR systems have specific advantages up to 200 MWth compared to other reactor types at least being adapted for single- and dual-purpose desalination plants. The calculated costs of the desalinated water show that due to fuel cost advantages of reactors small and medium nuclear desalination plants are economically competetive with oil-fired plants since the steep rise of oil price in autumn 1973. (author)

Thermal-Economic Modularization of Small, Organic Rankine Cycle Power Plants for Mid-Enthalpy Geothermal Fields

Directory of Open Access Journals (Sweden)

Yodha Y. Nusiaputra

2014-07-01

Full Text Available The costs of the surface infrastructure in mid-enthalpy geothermal power systems, especially in remote areas, could be reduced by using small, modular Organic Rankine Cycle (ORC power plants. Thermal-economic criteria have been devised to standardize ORC plant dimensions for such applications. We designed a modular ORC to utilize various wellhead temperatures (120–170 °C, mass flow rates and ambient temperatures (−10–40 °C. A control strategy was developed using steady-state optimization, in order to maximize net power production at off-design conditions. Optimum component sizes were determined using specific investment cost (SIC minimization and mean cashflow (MCF maximization for three different climate scenarios. Minimizing SIC did not yield significant benefits, but MCF proved to be a much better optimization function.

Pollution and power generation: environmental implications Small Hydroelectric Plants of Sao Paulo

Directory of Open Access Journals (Sweden)

Giorgia Limnios

2015-06-01

Full Text Available The current situation of water scarcity of of São Paulo State, manifested as imminent risk of shortages in major urban areas, has led not only to issues concerning preservation of water resources, but also problems related to energy availability, identified in a series of expeditions field carried out under the project " Electricity History of the State of Sao Paulo (1890-1960: Industrial Heritage , Landscape and Environment – Electromemory II”. The objective of this project is to study an extremely representative set of power plants and small hydroelectric power plants built during the initial period of electrification of the State of São Paulo – Brazil (1890-1960, along with its evolution within the social, historical and geographical aspects, to highlight the landscape changes resulting from the electrification process, as well as beneficiaries and impacts on landscape during the study period. In all visits, in addition to the problem of water scarcity, we verified that the power plants face generation constraints related to severe water pollution, either by diffuse or point sources. Some studies conducted in Brazil have analyzed the interference of pollution in power generation , highlighting the role of diffuse sources such as solid waste, sediments from areas with strong erosion, lubricant oils from vehicles or the development of invasive species, particularly as macrophytes, causative agents of biochemical changes that promote the formation of chemical compounds able to erode the electromechanical equipment of the plants or even prevent the flow of water intake into the same. The power plants covered by Electromemory II Project scope have these same problems, which prompted the need to establish a relationship between pollution in its various forms and the generation of electricity. To establish this bridge, the survey of publications and technical reports was necessary as well asresearches inenvironmental legislation

Childhood leukemia near nuclear plants in the United Kingdom: The evolution of a systematic approach to studying rare disease in small geographic areas

International Nuclear Information System (INIS)

Beral, V.

1990-01-01

A cluster of childhood leukemia in a village near a nuclear plant in northern England prompted further studies of cancer in the vicinity of other nuclear plants in the United Kingdom. These studies demonstrated that the risk of childhood leukemia was increased near certain other nuclear plants. Although the reasons for the increase are still unclear, the scientific debate stimulated by these findings has clarified some of the special methodological problems encountered when studying rare diseases in small areas. Firstly, unless a specific hypothesis is defined in advance, the relevance of a single geographic cluster of disease can rarely be interpreted. Even when a prior hypothesis exists, the small number of cases which generally occur in a small area make the findings highly sensitive to reporting, diagnostic, or classification errors. The statistical power of such investigations is also usually low and only marked increases in risk can be detected. Furthermore, conventional statistical tests may be inappropriate if the underlying spatial distribution of the disease is not random; and little is known about the background distribution of disease in small areas. Investigations of specific hypotheses about defined sources of environmental contamination, especially if they can be replicated, are more likely to result in conclusive findings that are in-depth studies of individual clusters

Biofiltration and electrochemical treatment for the production of service water from outflows of small-scaled sewage treatment plants; Biofiltration und elektrochemische Behandlung zur Brauchwassererzeugung aus Kleinklaeranlagenablaeufen

Energy Technology Data Exchange (ETDEWEB)

Ilian, Jens

2010-12-14

Up to the 1990s a mechanical partly biological wastewater treatment was performed at remote locations or collected in reservoirs without outflow. The currently valid legal regulations require a biological treatment of wastewater. Thus, biological small-scale sewage treatment plants experience a broad dissemination recently. Under this aspect, the author of the contribution under consideration reports on the bio filtration and electrochemical treatment in order to produce service water from outflows of small-scale sewage treatment plants. The author investigates the legal regulations, and supplements these regulations by own definitions and requirements on the consideration of a hygienic potential for damage. Additionally, investigations on the cleaning performance of properly operated small-scaled sewage treatment plants are performed. The hygienic risk potential as an inflow condition of a disinfection is determined.

Impact of Wind Power Plants with Full Converter Wind Turbines on Power System Small-Signal Stability

DEFF Research Database (Denmark)

Knüppel, Thyge; Nygaard Nielsen, Jørgen; Dixon, Andrew

Wind power is being developed in power systems all around the world, and already today wind power covers more than 20 % of the electricity consumption in some countries. As the size of each wind power plant (WPP) increases and as the levels of penetration reaches certain magnitudes, the inclusion...... of the dynamic properties of the WPPs in the power system stability studies become important. The work presented in this report deal with the impact of WPPs based on full converter wind turbines (WTs) on the power system small-signal rotor angle stability. During small disturbances in the power system, the rotor...... speed of the synchronous machines will eventually return to its steady state if the power system is small-signal stable. The dynamic properties of a WPP are fundamentally dierent from those of a synchronous machine, and the interaction of WPPs with the synchronous machines in power system oscillations...

A multi-stage-flash desalination plant of relative small performance with an integrated pressurized water reactor as a nuclear heat source

International Nuclear Information System (INIS)

Peltzer, M.; Petersen, G.

1976-01-01

In the Krupp-GKSS joint study MINIPLEX the requirements for seawater-desalination-plants with a performance in the range of 10,000 to 80,000 m 3 /d heated by a nuclear reactor are investigated. The reactor concept is similar to the integrated pressurized water reactor (IPWR) of the nuclear ship OTTO HAHN. The calculated costs of the desalinated water show, that due to the fuel cost advantages of reactors small and medium nuclear desalination plants are economically competetive with oil-fired plants since the steep rise of oil price in autumn 1973. (orig.) [de

Comprehensive evaluation of the main technology for new sewage treatment plants in small towns along the Duliujian river basin

Science.gov (United States)

Chen, Yiming; Zhou, Beihai; Yuan, Rongfang; Bao, Xiangming; Li, Dongwei

2018-02-01

In recent years, water contamination problem has been becoming more and more serious due to increasing wastewater discharge. So our country has accelerated the pace of constructing sewage treatment plant in small towns. But in China it has not been issued any corresponding technical specifications about the choice of treatment technology. So the article is based on the basin of Duliujian river, through field research, data collection and analysis of relevant documentations, preliminarily elects seven kinds of technology: Improved A2/O, Integrated oxidation ditch, Orbal oxidation ditch, CASS, A/O+refined diatomite, BIOLAK and UNITANK as alternatives for Tianjin sewage discharge local standard.Then the article use the analytic hierarchy process (AHP) to evaluate the seven kinds of alternatives, finally it is concluded that CASS technology is most suitable for the main technology of new sewage treatment plants in small towns along the Duliujian River basin.

The Planning of a Small Pilot Plant for Development Work on Aqueous Reprocessing of Nuclear Fuels

Energy Technology Data Exchange (ETDEWEB)

Sjoeborg, T U; Haeffner, E; Hultgren, Aa

1963-10-15

A shielded volume (42 m{sup 3}) in the hot laboratory at Kjeller, Norway, has been used for the installation of a small pilot plant intended for studies on nuclear fuel reprocessing. During the first period of operation (1963) a plutonium separation method (the Silex process) developed at AB Atomenergi will be studied. This document is a description of the project during the stage of technical planning and chemical process development.

The challenge of introducing high-temperature reactor plants onto the international power plant market

International Nuclear Information System (INIS)

Bogen, J.; Stoelzl, D.

1987-01-01

Growth of world population increases energy demand until the year 2000 and afterwards. Electricity growth rates in industrialized nations are lower after the oil price escalation in 1973 and 1979, and in developing countries grid sizes are often too small for the operation of large LWR plants. This indicates a potential for small and medium-sized power reactors such as the HTR-100 and the HTR-500. These plants can compete with coal fired plants of comparable size. An HTR-500 is even competitive, considering the electricity generating cost of large LWR plants. The special advantages of HTR plants in the small and medium-capacity range are discussed. (orig.)

The challenge of introducing high-temperature-reactor plants onto the international power plant market

International Nuclear Information System (INIS)

Bogen, J.; Stoelzl, D.

1988-01-01

Growth of world population increases energy demand until the year 2000 and afterwards. Electricity growth rates in industrialized nations are lower after the oil price escalation in 1973 and 1979, and in developing countries grid sizes are often too small for the operation of large LWR plants. This indicates a potential for small and medium-sized power reactors such as the HTR-100 and the HTR-500. These plants can compete with coal fired plants of comparable size. An HTR-500 is even competitive, considering the electricity generating cost of large LWR plants. The special advantages of HTR plants in the small and medium-capacity range are discussed. (orig.)

A plant small polypeptide is a novel component of DNA-binding protein phosphatase 1-mediated resistance to plum pox virus in Arabidopsis.

Science.gov (United States)

Castelló, María José; Carrasco, Jose Luis; Navarrete-Gómez, Marisa; Daniel, Jacques; Granot, David; Vera, Pablo

2011-12-01

DNA-binding protein phosphatases (DBPs) have been identified as a novel class of plant-specific regulatory factors playing a role in plant-virus interactions. NtDBP1 from tobacco (Nicotiana tabacum) was shown to participate in transcriptional regulation of gene expression in response to virus infection in compatible interactions, and AtDBP1, its closest relative in the model plant Arabidopsis (Arabidopsis thaliana), has recently been found to mediate susceptibility to potyvirus, one of the most speciose taxa of plant viruses. Here, we report on the identification of a novel family of highly conserved small polypeptides that interact with DBP1 proteins both in tobacco and Arabidopsis, which we have designated DBP-interacting protein 2 (DIP2). The interaction of AtDIP2 with AtDBP1 was demonstrated in vivo by bimolecular fluorescence complementation, and AtDIP2 was shown to functionally interfere with AtDBP1 in yeast. Furthermore, reducing AtDIP2 gene expression leads to increased susceptibility to the potyvirus Plum pox virus and to a lesser extent also to Turnip mosaic virus, whereas overexpression results in enhanced resistance. Therefore, we describe a novel family of conserved small polypeptides in plants and identify AtDIP2 as a novel host factor contributing to resistance to potyvirus in Arabidopsis.

Plants and butterflies of a small urban preserve in the Central Valley of Costa Rica

OpenAIRE

Kenji Nishida; Ichiro Nakamura; Carlos O Morales

2009-01-01

Costa Rica’s most populated area, the Central valley, has lost much of its natural habitat, and the little that remains has been altered to varying degrees. Yet few studies have been conducted to assess the need for conservation in this area. We present preliminary inventories of plants, butterflies, and day-flying moths of the Reserva Ecológica Leonelo Oviedo (RELO), a small Premontane Moist Forest preserve within the University of Costa Rica campus, located in the urbanized part of the vall...

Hydroelectric Power Plants Dobsina

International Nuclear Information System (INIS)

Majercak, V.; Srenkelova, Z.; Kristak, J.G.

1997-01-01

In this brochure the Hydroelectric Power Plants Dobsina, (VED), subsidiary of the utility Slovenske Elektrarne, a.s. (Slovak Electric, plc. Bratislava) are presented. VED is mainly aimed at generating peak-load electrical energy and maintenance of operational equipment. Reaching its goals, company is first of all focused on reliability of production, economy and effectiveness, keeping principles of work safety and industry safety standards and also ecology. VED operates eight hydroelectric power plants, from which PVE Ruzin I and PVE Dobsina I are pump storage ones and they are controlled directly by the Slovak Energy Dispatch Centre located in Zilina thought the system LS 3200. Those power plants participate in secondary regulation of electrical network of Slovakia. They are used to compensate balance in reference to foreign electrical networks and they are put into operation independently from VED. Activity of the branch is focused mainly on support of fulfilment of such an important aim as electric network regulation. Beginnings of the subsidiary Hydroelectric Power Plants Dobsina are related to the year of 1948. After commissioning of the pump storage Hydroelectric Power Plants Dobsina in 1953, the plant started to carry out its mission. Since that time the subsidiary has been enlarged by other seven power plants, through which it is fulfilling its missions nowadays. The characteristics of these hydroelectric power plants (The pump-storage power plant Dobsina, Small hydroelectric power plant Dobsina II, Small hydroelectric power plant Rakovec, Small hydroelectric power plant Svedlar, Hydroelectric power plant Domasa, The pump-storage power plant Ruzin, and Small hydroelectric power plant Krompachy) are described in detail. Employees welfare and public relations are presented

Workplace activities to promote small attempts for safety. Toward development of safety culture in a nuclear power plant

International Nuclear Information System (INIS)

Fukui, Hirokazu; Sugiman, Toshio

2007-01-01

Activities that could possibly grow into learning activities for developing safety culture were explored by intensive fieldwork in a nuclear power plant depending on Engestroem's activity theory. As a first step to achieve this goal, workers' small attempts that might contribute to nurturing a safety culture were investigated. Eight kinds of activity were observed and interpreted as having the possibility to facilitate small recognition and small practice, i.e., activities including (1) workgroup as community, (2) other workgroups and other departments as community, (3) meeting drawing remarks as mediating artifacts, (4) study session and Off-the-Job-Training as mediating artifact, (5) award as mediating artifact, (6) extended leave as mediating artifact, (7) check sheet as mediating artifact, and (8) skill-transfer system as mediating artifact. (author)

Modeling operator actions during a small break loss-of-coolant accident in a Babcock and Wilcox nuclear power plant

International Nuclear Information System (INIS)

Ghan, L.S.; Ortiz, M.G.

1991-01-01

A small break loss-of-accident (SBLOCA) in a typical Babcock and Wilcox (B ampersand W) nuclear power plant was modeled using RELAP5/MOD3. This work was performed as part of the United States Regulatory Commission's (USNRC) Code, Scaling, Applicability and Uncertainty (CSAU) study. The break was initiated by severing one high pressure injection (HPI) line at the cold leg. Thus, the small break was further aggravated by reduced HPI flow. Comparisons between scoping runs with minimal operator action, and full operator action, clearly showed that the operator plays a key role in recovering the plant. Operator actions were modeled based on the emergency operating procedures (EOPs) and the Technical Bases Document for the EOPs. The sequence of operator actions modeled here is only one of several possibilities. Different sequences of operator actions are possible for a given accident because of the subjective decisions the operator must make when determining the status of the plant, hence, which branch of the EOP to follow. To assess the credibility of the modeled operator actions, these actions and results of the simulated accident scenario were presented to operator examiners who are familiar with B ampersand W nuclear power plants. They agreed that, in general, the modeled operator actions conform to the requirements set forth in the EOPs and are therefore plausible. This paper presents the method for modeling the operator actions and discusses the simulated accident scenario from the viewpoint of operator actions

Covalent attachment of the plant natural product naringenin to small glass and ceramic beads

Directory of Open Access Journals (Sweden)

Grotewold Erich

2005-10-01

Full Text Available Abstract Background Natural products have numerous medicinal applications and play important roles in the biology of the organisms that accumulate them. Few methods are currently available for identifying proteins that bind to small molecules, therefore the discovery of cellular targets for natural products with pharmacological activity continues to pose a significant challenge in drug validation. Similarly, the identification of enzymes that participate in the biosynthesis or modification of natural products remains a formidable bottleneck for metabolic engineering. Flavonoids are one large group of natural products with a diverse number of functions in plants and in human health. The coupling of flavonoids to small ceramic and glass beads provides a first step in the development of high-throughput, solid-support base approaches to screen complex libraries to identify proteins that bind natural products. Results The utilization of small glass and ceramic beads as solid supports for the coupling of small molecules was explored. Initial characterization of the beads indicated uniform and high capacity loading of amino groups. Once the beads were deemed adequate for the linking of small molecules by the coupling of NHS-fluorescein followed by microscopy, chemical hydrolysis and fluorometry, the flavonoid naringenin was modified with 1,4-dibromobutane, followed by the attachment of aminopropyltriethoxysilane. After NMR structural confirmation, the resulting 7-(4-(3-(triethoxysilylpropylaminobutoxy naringenin was attached to the ceramic beads. Conclusion Our results demonstrate that ceramic and glass beads provide convenient solid supports for the efficient and facile coupling of small molecules. We succeeded in generating naringenin-coupled ceramic and glass beads. We also developed a convenient series of steps that can be applied for the solid-support coupling of other related flavonoids. The availability of solid-support coupled naringenin opens

Forest Distribution on Small Isolated Hills and Implications on Woody Plant Distribution under Threats of Global Warming

Directory of Open Access Journals (Sweden)

Chi-Cheng Liao

2012-09-01

Full Text Available Treelines have been found to be lower in small isolated hilltops, but the specific dynamics behind this unique phenomenon are unknown. This study investigates the distribution patterns of woody plants in Yangmingshan National Park (YMSNP, Northern Taiwan in search of the limitation mechanisms unique to small isolated hills, and to evaluate potential threats under global warming. Forests distributed between 200 to 900 m above sea level (ASL. Remnant forest fragments between 400 and 900 m ASL, have the highest species richness, and should be protected to ensure future forest recovery from the former extensive artificial disturbance. The lower boundary is threatened by urban and agricultural development. The lack of native woody species in these low elevation zones may cause a gap susceptible to invasive species. A consistent forest line at 100 m below mountain tops regardless of elevation suggests a topography-induced instead of an elevation-related limiting mechanism. Therefore, upward-shift of forests, caused by global warming, might be limited at 100 m below hilltops in small isolated hills because of topography-related factors. The spatial range of woody plants along the altitudinal gradient, thus, is likely to become narrower under the combined pressures of global warming, limited elevation, exposure-related stress, and artificial disturbance. Management priorities for forest recovery are suggested to include preservation of remnant forest fragments, increasing forest connectivity, and increasing seedling establishment in the grasslands.

Small-scale hybrid plant integrated with municipal energy supply system

International Nuclear Information System (INIS)

Bakken, B.H.; Fossum, M.; Belsnes, M.M.

2001-01-01

This paper describes a research program started in 2001 to optimize environmental impact and cost of a small-scale hybrid plant based on candidate resources, transportation technologies and conversion efficiency, including integration with existing energy distribution systems. Special attention is given to a novel hybrid energy concept fuelled by municipal solid waste. The commercial interest for the model is expected to be more pronounced in remote communities and villages, including communities subject to growing prosperity. To enable optimization of complex energy distribution systems with multiple energy sources and carriers a flexible and robust methodology must be developed. This will enable energy companies and consultants to carry out comprehensive feasibility studies prior to investment, including technological, economic and environmental aspects. Governmental and municipal bodies will be able to pursue scenario studies involving energy systems and their impact on the environment, and measure the consequences of possible regulation regimes on environmental questions. This paper describes the hybrid concept for conversion of municipal solid waste in terms of energy supply, as well as the methodology for optimizing such integrated energy systems. (author)

Small bore pipe acceptance criteria for watts bar nuclear plant Tennessee Valley Authority

International Nuclear Information System (INIS)

Sun, W.S.; Lee, R.L.; Kalyanan, N.

1991-01-01

Small bore pipe (≤2 inches NPS) is traditionally analyzed by simplified techniques using Cook Book approach, which yield conservative results. However, reconciliation of these systems for as-built condition where the original criteria is observed to have been exceeded (or due to additions etc.) generally becomes a time consuming and expensive operation since a rigorous computer aided analysis or a detailed hand calculation becomes necessary. The acceptance criteria in this paper can be effectively used in such cases. The approach involves utilizing basic engineering principles and plant specific parameters (such as earthquake spectra) to estimate the system response such as pipe stress due to various loading conditions, piping frequency, support and anchor loads, valve acceleration etc

Technology, safety and costs of decommissioning a reference small mixed oxide fuel fabrication plant. Volume 1. Main report

Energy Technology Data Exchange (ETDEWEB)

Jenkins, C. E.; Murphy, E. S.; Schneider, K J

1979-01-01

Detailed technology, safety and cost information are presented for the conceptual decommissioning of a reference small mixed oxide fuel fabrication plant. Alternate methods of decommissioning are described including immediate dismantlement, safe storage for a period of time followed by dismantlement and entombment. Safety analyses, both occupational and public, and cost evaluations were conducted for each mode.

Economic performance of small scale hydroelectric power plants: `Results center`; Desempenho economico de PCH`s: centro de resultados

Energy Technology Data Exchange (ETDEWEB)

Cipoli, Jose Adolfo; Silva, Jose Paulo Mendes [Companhia Paulista de Forca e Luz (CPFL), Campinas, SP (Brazil)

1995-12-31

This work presents the experience concerning the creation of an imaginary company named `CPFL Generator`, composed by 20 small scale hydroelectric power plants. The main idea of the project is to analyse the economic performance of each unit individually and the group as a company, enabling to a better quality management 3 refs., 1 fig., 7 tabs.

High altitude artisanal small-scale gold mines are hot spots for Mercury in soils and plants

International Nuclear Information System (INIS)

Terán-Mita, Tania A.; Faz, Angel; Salvador, Flor; Arocena, Joselito M.; Acosta, Jose A.

2013-01-01

Mercury releases from artisanal and small-scale gold mines (ASGM) condense and settle on plants, soils and water bodies. We collected soil and plant samples to add knowledge to the likely transfer of Hg from soils into plants and eventually predict Hg accumulation in livestock around ASGM in Bolivia. Mean contents of Hg in soils range from 0.5 to 48.6 mg Hg kg −1 soil (5× to 60× more compared to control sites) and exceeded the soil Hg threshold levels in some European countries. The Hg contents ranged from 0.6 to 18 and 0.2 to 28.3 mg Hg kg −1 leaf and root, respectively. The high Hg in Poaceae and Rosaceae may elevate Hg accumulation into the food chain because llama and alpaca solely thrive on these plants for food. Erosion of soils around ASGM in Bolivia contributes to the Hg contamination in lower reaches of the Amazon basin. - Highlights: ► Hg in soils ranged from 0.5 to 48.6 mg Hg kg −1 soil, and at least 5× to 60× more than control sites. ► Plants near gold mines exceed the 0.1 mg Hg kg −1 plant material European limit for feed quality. ► Camelids feeding on plants with high Hg may elevate Hg levels in foods (meats) for the miners. ► Soils with high Hg can be significant Hg sources to the contamination of the Amazon basin. - Mean contents of Hg in soils were at least 5× to 60× more compared to Hg in control sites, and the high Hg in Poaceae and Rosaceae may elevate Hg into the food chain.

The emergence of small hydroelectric plants and the urbanization process in the hinterland of São Paulo state (1890-1930)

OpenAIRE

Mortati, Débora Marques de Almeida Nogueira; Argollo Ferrão, André Munhoz de

2011-01-01

The period focused in this paper is from 1890 to 1930, when São Paulo state began its industrialization process, the coffee economy was booming and, in that context, it was founded the first hydroelectric power company in the state. This panorama advanced till 1930, when the coffee economy began in crisis, the industry was already established and the construction of hydroelectric plants after 1930 takes on another course: the large dams, closing the cycle of small hydroelectric plants. The el...

Policy for rekindling and re-powering of small scale hydroelectric power plants; Politica de rejuvenescimento e repotenciacao de PCH`s

Energy Technology Data Exchange (ETDEWEB)

Souza, Wanderley I. de [Companhia Paulista de Forca e Luz (CPFL), Campinas, SP (Brazil). Div. de Geracao

1997-12-31

The demand of electric energy comes increasing gradually and the offer of energy with of growth of the market, becomes a product, a great concern. In this matter Small Hydroelectric Power Plant SHP`s can be fundamental to offer support to the electric section, but these small sources of energy need to be adapting rekindling and repowering, being used of new market technologies and of economic studies that can give reliability and speed in the evaluations of the processes. (author)

Small-scale hydro-power plant in Quinto - Preliminary project; Progetto minicentrale idroelettrica, Ri Secco - Quinto. Programma piccole centrali idrauliche. Progetto di massima

Energy Technology Data Exchange (ETDEWEB)

Dotti, R. [Reali e Guscetti SA, Ambri (Switzerland); Rosselli, P. [Celio Engineering SA, Ambri (Switzerland)

2009-06-15

This report for the Swiss Federal Office of Energy (SFOE) takes a look at a project for the realisation of a small hydro-power plant on the alpine stream 'Ri Secco' in the municipality of Quinto, southern Switzerland. The Ri Secco partly flows in a steep canyon. The elevation difference of 810 or 620 m (depending on the location of the water deviation from the stream) is favorable to the installation of a small-scale high-head power plant. The report presents details on the hydrological data and the dimensioning of the installation. Several variants are considered, which also include two possible penstock diameters for each weir location. The electricity production expected is discussed, as is the economic viability of the project.

Analysis of world experience in constructing underground small nuclear power plants and assessment of its potential use in the Russian Arctic regions

Directory of Open Access Journals (Sweden)

Smirnov Yu. G.

2016-03-01

Full Text Available The paper considers the common ideology and main idea of locating underground nuclear plants. Specific examples in domestic and foreign experience have been analyzed. It has been established that underground small nuclear power plants can be used as an alternative source of electric and thermal energy for solving defense-strategic and social-economic tasks particularly when developing mineral raw material resources in the Russian Arctic regions

Iodine-131 in sewage sludge from a small water pollution control plant serving a thyroid cancer treatment facility.

Science.gov (United States)

Rose, Paula S; Swanson, R Lawrence

2013-08-01

Iodine-131 (half-life = 8.04 d) is the most widely used radionuclide in medicine for therapeutic purposes. It is excreted by patients and is discharged directly to sewer systems. Despite considerable dilution in waste water and the relatively short half-life of I, it is readily measured in sewage. This work presents I concentrations in sewage sludge from three water pollution control plants (WPCPs) on Long Island, NY. Iodine-131 concentrations ranged from 0.027 ± 0.002 to 148 ± 4 Bq g dry weight. The highest concentrations were measured in the Stony Brook WPCP, a relatively small plant (average flow = 6.8 × 10 L d) serving a regional thyroid cancer treatment facility in Stony Brook, NY. Preliminary radiation dose calculations suggested further evaluation of dose to treatment plant workers in the Stony Brook WPCP based on the recommendations of the Interagency Steering Committee on Radiation Standards.

Biomass and bio-fuel based poly-generation for off-grid and grid-connected operation. Final technical report

Energy Technology Data Exchange (ETDEWEB)

2012-07-01

The overall objective of this project was to design and build a combined heat and power plant based on an updraft gasifier and a 35 kW electrical output Stirling engine and further to test the flexibility of the plant with regards to fuel and application. In the project a containerized combined heat and power plant including a 200 kW updraft gasifier and a 35 kW electrical output Stirling engine was designed, the specified components were procured, the plant was installed in the three containers and the plant was erected at Amagerforbraendingen ready for the COP15 in November 2009. The potential of operating the Stirling engine in island-mode (without grid connection) was investigated by mathematical modelling. Using an absorption cooling plant connected to the Stirling CHP plant was also investigated. A technical feasibility study was undertaken and it was concluded that from the two available technologies (water/LiBr and Ammonia/water) the appropriate choice is depending on the required cooling temperature. Test runs focussed on investigating the fuel flexibility of two different configurations of Stirling engine CHP plants were carried out - respectively the updraft gasifier plant (the containerized plant and the DTU plant) and the pyrolysis plant (the plant situated at Barritskov). In order to perform these test runs a stable operation is required. On both the containerized plant and the pyrolysis plant this proved to be more challenging than expected and therefore the number of fuels tested was limited to willow chips at the containerized plant and dry wood residues, wood pellets and straw pellets on the pyrolysis plant. For all tested fuels it was possible to operate the plants, however different issues mainly related to the quality of the fuels were encountered. And so it can be concluded that the quality of the fuel is critical for the operation of both the updraft gasifier plant and the pyrolysis plant. A comprehensive desktop evaluation of the feasibility

Development of a GIS Tool for High Precision PV Degradation Monitoring and Supervision: Feasibility Analysis in Large and Small PV Plants

Directory of Open Access Journals (Sweden)

Miguel de Simón-Martín

2017-06-01

Full Text Available It is well known that working photovoltaic (PV plants show several maintenance needs due to wiring and module degradation, mismatches, dust, and PV cell defects and faults. There are a wide range of theoretical studies as well as some laboratory tests that show how these circumstances may affect the PV production. Thus, it is mandatory to evaluate the whole PV plant performance and, then, its payback time, profitability, and environmental impact or carbon footprint. However, very few studies include a systematic procedure to quantify and supervise the real degradation effects and fault impacts on the field. In this paper, the authors first conducted a brief review of the most frequent PV faults and the degradation that can be found under real conditions of operation of PV plants. Then, they proposed and developed an innovative Geographic Information System (GIS application to locate and supervise them. The designed tool was applied to both a large PV plant of 108 kWp and a small PV plant of 9 kWp installed on a home rooftop. For the large PV plant, 24 strings of PV modules were modelized and introduced into the GIS application and every module in the power plant was studied including voltage, current, power, series and parallel resistances, fill factor, normalized PV curve to standard test conditions (STC, thermography and visual analysis. For the small PV installation three strings of PV panels were studied identically. It must be noted that PV modules in this case included power optimizers. The precision of the study enabled the researchers to locate and supervise up to a third part of every PV cell in the system, which can be adequately georeferenced. The developed tool allows both the researchers and the investors to increase control of the PV plant performance, to lead to better planning of maintenance actuations, and to evaluate several PV module replacement strategies in a preventive maintenance program. The PV faults found include hot

Model Thermoelectric Generator TEG Small Modular As Micro Electricity Plant At Indonesia Part 1 Design And Material

Directory of Open Access Journals (Sweden)

Kisman M. Mahmud

2015-08-01

Full Text Available Thermoelectrically Generator TEG can generate electricity from the temperature difference between hot and cold at the junction thermoelectric module with two different semiconductor materials there will be a flow of current through the junction so as to produce a voltage. This principle uses the Seebeck effect thermoelectric generator as a base. By using these principles this study was conducted to determine the potential of the electric energy of the two Peltier modules which would be an alternative source for micro electricity plant using heat from methylated. The focus of this research is to design a model TEG Thermoelectric Generator Small Modular to produce the kind of material that is optimum for a TEG on the simulation Computer Aided Design CAD with a variety of four different materials that Bi2Te3 Bismuth Telluride PbTe-BiTe CMO-32 -62S Cascade and CMO-32-62S Calcium Manganese Oxide to its cold side using the heat sink fan and simulating heat aluminum plate attached to the hot side of the TEG modules with heat source of methylated. Model simulation results on TEG Small Modular micro electrical plant material obtained CMO-32-62S Cascade thermal material that has a value greater than 3 other material.

Small hydro

International Nuclear Information System (INIS)

Bennett, K.; Tung, T.

1995-01-01

A small hydro plant in Canada is defined as any project between 1 MW and 15 MW but the international standard is 10 MW. The global market for small hydro development was considered good. There are some 1000 to 2000 MW of generating capacity being added each year. In Canada, growth potential is considered small, primarily in remote areas, but significant growth is anticipated in Eastern Europe, Africa and Asia. Canada with its expertise in engineering, manufacturing and development is considered to have a good chance to take advantage of these growing markets

Small-scale CHP Plant based on a 35 kWel Hermetic Four Cylinder Stirling Engine for Biomass Fuels- Development, Technology and Operating Experiences

DEFF Research Database (Denmark)

Obernberger, I.; Carlsen, Henrik; Biedermann, F.

2003-01-01

) process and the Stirling engine process. The ORC process represents an economically interesting technology for small-scale biomass-fired combined heat and power plants in a power range between 400 and 1,500 kWel. A newly developed ORC technology with a nominal electric capacity of 1,000 kW was implemented...... in the biomass CHP plant Lienz (A) in the framework of an EU demonstration project. This plant was put in operation in February 2002. Stirling engines are a promising solution for installations with nominal electric capacities between 10 and 150 kW. A biomass CHP pilot plant based on a 35 kWel-Stirling engine...

The development of small-scale mechanization means positioning algorithm using radio frequency identification technology in industrial plants

Science.gov (United States)

Astafiev, A.; Orlov, A.; Privezencev, D.

2018-01-01

The article is devoted to the development of technology and software for the construction of positioning and control systems for small mechanization in industrial plants based on radio frequency identification methods, which will be the basis for creating highly efficient intelligent systems for controlling the product movement in industrial enterprises. The main standards that are applied in the field of product movement control automation and radio frequency identification are considered. The article reviews modern publications and automation systems for the control of product movement developed by domestic and foreign manufacturers. It describes the developed algorithm for positioning of small-scale mechanization means in an industrial enterprise. Experimental studies in laboratory and production conditions have been conducted and described in the article.

The process of granting of the authorization-registration of small-scale hydroelectric power plant; O processo de outorga de autorizacao-registro de PCHs

Energy Technology Data Exchange (ETDEWEB)

Lago, Rosangela; Nobrega, Andre Pepitone da [Agencia Nacional de Energia Eletrica (ANEEL), Brasilia, DF (Brazil). Superintendencia de Concessoes e Autorizacoes de Geracao

2002-07-15

Small hydroelectric power plant represent a fast and efficient way of promoting the expansion of electricity supply in order to meet the growing demand in the market place. Due to its characteristics, this type of enterprises operated enables better meet the needs of potential in small urban centers and rural regions, since, in most cases, complements the provision made by the interconnected system.

A complex small RNA repertoire is generated by a plant/fungal-like machinery and effected by a metazoan-like Argonaute in the single-cell human parasite Toxoplasma gondii.

Directory of Open Access Journals (Sweden)

Laurence Braun

2010-05-01

Full Text Available In RNA silencing, small RNAs produced by the RNase-III Dicer guide Argonaute-like proteins as part of RNA-induced silencing complexes (RISC to regulate gene expression transcriptionally or post-transcriptionally. Here, we have characterized the RNA silencing machinery and exhaustive small RNAome of Toxoplasma gondii, member of the Apicomplexa, a phylum of animal- and human-infecting parasites that cause extensive health and economic damages to human populations worldwide. Remarkably, the small RNA-generating machinery of Toxoplasma is phylogenetically and functionally related to that of plants and fungi, and accounts for an exceptionally diverse array of small RNAs. This array includes conspicuous populations of repeat-associated small interfering RNA (siRNA, which, as in plants, likely generate and maintain heterochromatin at DNA repeats and satellites. Toxoplasma small RNAs also include many microRNAs with clear metazoan-like features whose accumulation is sometimes extremely high and dynamic, an unexpected finding given that Toxoplasma is a unicellular protist. Both plant-like heterochromatic small RNAs and metazoan-like microRNAs bind to a single Argonaute protein, Tg-AGO. Toxoplasma miRNAs co-sediment with polyribosomes, and thus, are likely to act as translational regulators, consistent with the lack of catalytic residues in Tg-AGO. Mass spectrometric analyses of the Tg-AGO protein complex revealed a common set of virtually all known RISC components so far characterized in human and Drosophila, as well as novel proteins involved in RNA metabolism. In agreement with its loading with heterochromatic small RNAs, Tg-AGO also associates substoichiometrically with components of known chromatin-repressing complexes. Thus, a puzzling patchwork of silencing processor and effector proteins from plant, fungal and metazoan origin accounts for the production and action of an unsuspected variety of small RNAs in the single-cell parasite Toxoplasma and

PORTAFERM. A container-based small biogas plant with liquid manure as a feed material; PORTAFERM. Eine Containerbasierte Guelle-Kleinbiogasanlage

Energy Technology Data Exchange (ETDEWEB)

Klauss, M.; Matthes, J.

2010-09-15

Meanwhile, the energetic utilization of biogas is a substantial technology. The stock of biogas plants in Germany amounts nearly 4,500 in the year 2009. The average electrical output is approximately 370 kW. The most biogas facilities use regenerative raw materials as a feed material. With the second EEG amendment (EEG 2009), new incentives were set to the construction of biogas plants. A keyword here is the introduction of a liquid manure bonus. Under this aspect, the authors of the contribution under consideration report on a container-based biogas plant with liquid manure as a feed material. The test facility is equipped with a small cogeneration unit. In the basic operation, the produced masses of gas are sufficient for a daily operation between twelve to fourteen hours per day. With shortening the residence time gas volumes are produced which enable a continuous operation of the cogeneration units. Due to the large gas storage a peak load operation also is possible at a continuous gas production. A large advantage of this plant is that this plant does not have to run the total year.

Evaluation of the applicability of existing nuclear power plant regulatory requirements in the U.S. to advanced small modular reactors.

Energy Technology Data Exchange (ETDEWEB)

LaChance, Jeffrey L.; Wheeler, Timothy A.; Farnum, Cathy Ottinger; Middleton, Bobby D.; Jordan, Sabina Erteza; Duran, Felicia Angelica; Baum, Gregory A.

2013-05-01

The current wave of small modular reactor (SMR) designs all have the goal of reducing the cost of management and operations. By optimizing the system, the goal is to make these power plants safer, cheaper to operate and maintain, and more secure. In particular, the reduction in plant staffing can result in significant cost savings. The introduction of advanced reactor designs and increased use of advanced automation technologies in existing nuclear power plants will likely change the roles, responsibilities, composition, and size of the crews required to control plant operations. Similarly, certain security staffing requirements for traditional operational nuclear power plants may not be appropriate or necessary for SMRs due to the simpler, safer and more automated design characteristics of SMRs. As a first step in a process to identify where regulatory requirements may be met with reduced staffing and therefore lower cost, this report identifies the regulatory requirements and associated guidance utilized in the licensing of existing reactors. The potential applicability of these regulations to advanced SMR designs is identified taking into account the unique features of these types of reactors.

Small hydro plant- present scenario and future prospects

International Nuclear Information System (INIS)

Purohit, D.P.

1996-01-01

The article, deals with the methodology of power generation by small hydro power resources, especially in the Himalayan and sub Himalayan regions and the benefits it will bestow to the inhabitants of this region. The development of small hydro power projects in the Himalayas and sub Himalayas would serve as a model for environment- friendly sources of energy to benefit small communities world wide. The use of water turbine generators for the generation of cheaper power is also discussed. 4 refs

Study on the combustion behavior of radiolytically generated hydrogen explosion in small scale annular vessels at the reprocessing plant

International Nuclear Information System (INIS)

Kudo, Tatsuya; Tamauchi, Yoshikazu; Arai, Nobuyuki; Dai, Wenbin; Sakaihara, Motohiro; Kanehira, Osamu

2017-01-01

Hydrogen is generated by radiolysis of water, etc. in process vessels in reprocessing plant. Usually, the hydrogen is scavenged by compressed air into vessels to prevent hydrogen explosion. When an earthquake beyond design based occurs, for example, the compressed air may stop and the hydrogen starts accumulating in the vessels, and under this condition, an ignition source might set off hydrogen explosion. Therefore, the explosion derived by the radiolytically generated hydrogen is designated as one of severe accidents on Rokkasho Reprocessing Plant in new regulatory requirements. It is important to understand the combustion behavior of hydrogen explosion inside a vessel for consideration of safety measures against the severe accident, because the influences of detonation are not considered in the design basis of vessels. Especially, the investigations about the combustion behavior which considered influence of interior obstacles inside the vessel are not performed yet. In order to investigate the combustion behavior comprehensively, explosion experiment, combustion analysis and structural analysis are carried out using the representative vessels (small scale annular vessel, small scale plate vessel, large scale annular vessel and large scale cylindrical vessel) selected from Rokkasho Reprocessing Plant. In this paper, the results of experiments and analysis of small scale annular vessel (as one of representative vessel, imitated a pulsed column in the reprocessing plant) are reported. As imitated vessels, three vessels are manufactured with different interior obstacle arrangements as follows, A) cylindrical obstacles are faithfully reproduced and are arranged based on the actual vessel, B) cylindrical obstacles are arranged more densely than the actual vessel, and C) there are no obstacles inside the vessel. Experiments of hydrogen explosion are performed under condition of stoichiometric hydrogen-air ratio (premixed hydrogen-air is used). As a result of

Development of Inspection Technique for Socket Weld of Small Bore Piping in Nuclear Power Plant

International Nuclear Information System (INIS)

Yoon, Byungsik; Kim, Yongsik; Lee, Jeongseok

2013-01-01

The losses incurred by unplanned shutdowns are significant; consequently, early crack initiation and crack detection, including the detection of fillet weld manufacturing defects, is of the utmost importance. Current inspection techniques are not capable of reliably inspecting socket welds; therefore, new approaches are needed. The new technique must be sensitive to socket weld cracking, which usually initiates from the root, in order to detect the cracking during the early failure phase. In 2008, Kori unit 3 experienced leakage from the drain line socket weld of a steam generator. From this experience, KHNP enforced a management program to focus on enhancing the reliability of small bore socket weld piping inspections. Currently, conventional manual ultrasonic inspection techniques are used to detect service induced fatigue cracks. But there was uncertainty on manual ultrasonic inspection because of limited access to the welds and difficulties with contact between the ultrasonic probe and the OD surface of small bore piping. In this study, phased array ultrasonic inspection techniques are applied to increase inspection speed and reliability. Additionally a manually encoded scanner has been developed to enhance contact conditions and maintain constant signal quality. A phased array UT technique and system was developed to inspect small bore socket welds. The experimental results show all artificial flaws in the specimen were detected and measured. These experimental results show, that the newly developed inspection system, has improved the reliability and speed of small bore socket weld inspection. Based on these results, future works shall focus on additional experiments, with more realistic flaw responses. By applying this technique to the field, we expect that it can improve the integrity of small bore piping in nuclear power plants

Ecological impacts of small hydropower in China: Insights from an emergy analysis of a case plant

International Nuclear Information System (INIS)

Pang, Mingyue; Zhang, Lixiao; Ulgiati, Sergio; Wang, Changbo

2015-01-01

The belief that small hydropower (SHP) systems are sources of clean energy with few or no ecological problems has been driving the rapid expansion of SHP plants in China and elsewhere. This paper presents an evaluation of the ecological impacts of SHP based on an emergy analysis of a plant located in Guizhou Province in southwest China. The results suggest that periodic downstream drying-up of the river is the largest contributor to the induced ecological impacts in terms of emergy cost. In 2010, the ecosystem service losses caused by downstream ecosystem degradation totaled 2.35E+18 seJ, which accounts for 38% of the total emergy utilized in the annual operation of this plant. If such losses could be avoided, i.e., if the SHP operated as designed, SHP projects would produce relatively modest impacts on the environment. When the reaches downstream of the SHP plant are not affected, the environmental loading ratio (ELR) is 2.20 and the emergy sustainability index (ESI) is 0.93; however, the ELR increases to 3.82 and ESI decreases to 0.38 when river drying-up occurs. These results indicate that China should rigorously investigate potential ecological problems of SHP development and proceed with caution rather than readily believing unjustified assumptions. - Highlights: • Ecological impacts of a SHP plant in China are analyzed using emergy synthesis. • The ecosystem degradation due to periodic drying-up was the largest emergy cost. • The eco-friendliness of SHP is questionable when it is intensively developed. • China should proceed with caution regarding the potential ecological impact of SHP

Co-expression of peppermint geranyl diphosphate synthase small subunit enhances monoterpene production in transgenic tobacco plants.

Science.gov (United States)

Yin, Jun-Lin; Wong, Woon-Seng; Jang, In-Cheol; Chua, Nam-Hai

2017-02-01

Monoterpenes are important for plant survival and useful to humans. In addition to their function in plant defense, monoterpenes are also used as flavors, fragrances and medicines. Several metabolic engineering strategies have been explored to produce monoterpene in tobacco but only trace amounts of monoterpenes have been detected. We investigated the effects of Solanum lycopersicum 1-deoxy-d-xylulose-5-phosphate synthase (SlDXS), Arabidopsis thaliana geranyl diphosphate synthase 1 (AtGPS) and Mentha × piperita geranyl diphosphate synthase small subunit (MpGPS.SSU) on production of monoterpene and geranylgeranyl diphosphate (GGPP) diversities, and plant morphology by transient expression in Nicotiana benthamiana and overexpression in transgenic Nicotiana tabacum. We showed that MpGPS.SSU could enhance the production of various monoterpenes such as (-)-limonene, (-)-linalool, (-)-α-pinene/β-pinene or myrcene, in transgenic tobacco by elevating geranyl diphosphate synthase (GPS) activity. In addition, overexpression of MpGPS.SSU in tobacco caused early flowering phenotype and increased shoot branching by elevating contents of GA 3 and cytokinins due to upregulated transcript levels of several plastidic 2-C-methyl-d-erythritol-4-phosphate (MEP) pathway genes, geranylgeranyl diphosphate synthases 3 (GGPPS3) and GGPPS4. Our method would allow the identification of new monoterpene synthase genes using transient expression in N. benthamiana and the improvement of monoterpene production in transgenic tobacco plants. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Conifers have a unique small RNA silencing signature.

Science.gov (United States)

Dolgosheina, Elena V; Morin, Ryan D; Aksay, Gozde; Sahinalp, S Cenk; Magrini, Vincent; Mardis, Elaine R; Mattsson, Jim; Unrau, Peter J

2008-08-01

Plants produce small RNAs to negatively regulate genes, viral nucleic acids, and repetitive elements at either the transcriptional or post-transcriptional level in a process that is referred to as RNA silencing. While RNA silencing has been extensively studied across the different phyla of the animal kingdom (e.g., mouse, fly, worm), similar studies in the plant kingdom have focused primarily on angiosperms, thus limiting evolutionary studies of RNA silencing in plants. Here we report on an unexpected phylogenetic difference in the size distribution of small RNAs among the vascular plants. By extracting total RNA from freshly growing shoot tissue, we conducted a survey of small RNAs in 24 vascular plant species. We find that conifers, which radiated from the other seed-bearing plants approximately 260 million years ago, fail to produce significant amounts of 24-nucleotide (nt) RNAs that are known to guide DNA methylation and heterochromatin formation in angiosperms. Instead, they synthesize a diverse population of small RNAs that are exactly 21-nt long. This finding was confirmed by high-throughput sequencing of the small RNA sequences from a conifer, Pinus contorta. A conifer EST search revealed the presence of a novel Dicer-like (DCL) family, which may be responsible for the observed change in small RNA expression. No evidence for DCL3, an enzyme that matures 24-nt RNAs in angiosperms, was found. We hypothesize that the diverse class of 21-nt RNAs found in conifers may help to maintain organization of their unusually large genomes.

The Influence of Small-Scale Power Plant Supporting Schemes on the Public Trader and Consumers

Directory of Open Access Journals (Sweden)

Renata Varfolomejeva

2017-06-01

Full Text Available The mechanism of support schemes for achieving the required share of renewable energy sources (RES was implemented into the energy sector. The issued amount of support requires state subsidies. The end-users of electricity are paying the mandatory procurement component taxes to cover these subsidies. The article examines the way of minimizing the influence of the existing RES supporting schemes on the consumers. The fixed purchased electricity price in the case of RES does not encourage producers to operate at hours of peak consumption or when the price is high. Modification of the RES support mechanisms at the legislative level, firstly, could minimize the influence of the mandatory procurement component on the end-users’ electricity price, and secondly, could provide a great opportunity for the public trader to forecast the operation of small power plants and their generation abilities. Numerical experiments with models of two types of power plants (biofuel and hydropower prove the existence of a problem and the presence of a solution. This problem constitutes the main subject of the present paper.

Realization of safety culture into a reactor plant-4S (super safe, small and simple) LMR

International Nuclear Information System (INIS)

Hattori, S.; Ikemoto, I.; Minato, A.

1998-01-01

International Nuclear Safety Advisory Group (INSAG) defines Safety Culture as the following; Safety Culture is that assembly of characteristics and attitudes in organization and individuals which establishes that, as an overriding priority, nuclear plant safety issues receive the attention warranted by their significance. While such Safety Culture is certainly a critical element of nuclear safety assurance, it is important to design nuclear power facilities as friendly to operators as possible with minimum dependence on human factors. From the viewpoint of ensuring supply in our global society, it will be necessary to have multiple approaches to further promote the use of nuclear energy worldwide despite various social and cultural restrictions. It should then be considered, as prospective options, to disperse small nuclear power plants throughout the world under technical, social and cultural conditions. Under this circumstance, we have quested for and now propose a a scheme of assuring sheer safety of nuclear power plants by implementing operator-friendly nuclear reactors virtually free from human errors. The scheme specifically includes the measures for improving reliability through fabricating more compact reactors with a continuous in-factory production system, simplify maintenance and inspection of the reactor system using passive systems and further relieving operators of burden of labors. (author)

Assessment of the impact of nuclear power plant construction and operation on small regions

International Nuclear Information System (INIS)

Johnson, M.H. Jr.

1977-01-01

This study addresses the problem of the comprehensive, quantitative evaluation of the environmental, economic, and social impacts of the construction and operation of nuclear power plant on a given region. A theoretical model of the regional impacts is constructed employing input-output methods that are extended to include ecologic as well as economic effects. Thus, the regional model explicitly incorporates environmental feedback as a consequence of economic activity. The model is then employed to estimate the impact of the construction and operation of a nuclear power facility on a small region in South Carolina. Measures of economic and environmental effects include estimates of changes in output, income, employment, local government revenue and expenditure, external costs of environmental decay, pollution loads, and common-property resource usage. Results indicate that, in the South Carolina case study, significant gains in social welfare accrued to the region due to the construction and operation of the nuclear power facility. Further, the theoretical method developed herein provides a comprehensive method of objectively assessing various types of impacts on a region as small as several contiguous counties or even a single county

Access to realization of small hydroelectric power station in Republic of Macedonia

International Nuclear Information System (INIS)

Jakimova Filipovska, Nevenka

2001-01-01

In the paper an overview of the small-scale hydroelectric power plants is presented. The categorization groups of small to micro hydroelectric power plants by different countries are given. Also, the evaluation models of the projects for realization the small hydroelectric power plants are analysed. The aim of the paper is to stress the advantages of the small hydro projects and their implementation in Macedonia

Economic viability in concrete dams by multivariable regression tool for implantation of small hydroelectric plants

International Nuclear Information System (INIS)

Lima, Reginaldo Agapito de; Ribeiro Junior, Leopoldo Uberto

2010-01-01

For implantation of a SHP, the barrage is the main structure where its sizing represents from 30% - 50% of general cost of civil works. Considering this it is very important to have a fast, didactic and accurate tool for elaborating a budget, also allowing a quantitative analysis of inherent cost for civil building of barrages concrete made for small hydropower plants. In face of this, the multi changing regression tool is very important as it allows a fast and correct establishing of preliminary costs, even approximate, for estimates of barrages in concrete cost, enabling to ease the budget, guiding feasibility decisions for selecting or neglecting new alternatives of fall. (author)

Uses of plants, animal and mineral substances in Mediterranean ethno-veterinary practices for the care of small ruminants.

Science.gov (United States)

Piluzza, G; Virdis, S; Serralutzu, F; Bullitta, S

2015-06-20

The cultural heritage of Sardinian shepherds is rapidly vanishing and survives in the memory of elderly people. The objective of our study was not only to report the usage of plants and their preparation for administration but also the use of other remedies of different origin arising from traditional ethno-veterinary knowledge, as Sardinian shepherds were used to employ plants, animals, minerals and combinations of several substances to prepare remedies for prophylaxis or therapy on their animals. The work was carried out in rural areas of the island of Sardinia (Italy) by interviewing shepherds and filling questionnaires in order to record ethno-veterinary practices traditionally used for animal health care. Ethno-veterinary remedies traditionally utilised for treatments of small ruminants against ecto-and endo-parasites, gastrointestinal diseases, viral and bacterial diseases, wounds, sprains and bruises were identified. Non herbal remedies outnumbered the herbal ones, as usually plant species were mainly used for the care of cattle and equines. A total of 150 ethno-veterinary uses were documented for the treatment of 33 animal conditions, a detailed account of the formulations and their administration to sheep and goats was provided. Herbal remedies involved the use of twenty two spontaneous species and seven cultivated species. This study identifies remedies used in ethno-veterinary practices for small ruminants care in Sardinia, the second major Mediterranean island which has agro-pastoral activities dating back to Neolithic. Moreover, the danger of losing oral traditions, and the increasing attention towards traditional remedies as potential sources of natural products for improving animal health and welfare, support the interest of our survey. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

A novel family of small proteins that affect plant development

Energy Technology Data Exchange (ETDEWEB)

John Charles Walker

2011-04-29

The DVL genes represent a new group of plant proteins that influence plant growth and development. Overexpression of DVL1, and other members of the DVL family, causes striking phenotypic changes. The DVL proteins share sequence homology in their C-terminal half. Point mutations in the C-terminal domain show it is necessary and deletion studies demonstrate the C-terminal domain is sufficient to confer the overexpression phenotypes. The phenotypes observed, and the conservation of the protein sequence in the plant kingdom, does suggest the DVL proteins have a role in modulating plant growth and development. Our working hypothesis is the DVL proteins function as regulators of cellular signaling pathways that control growth and development.

Analysis of small RNA production patterns among the two potato spindle tuber viroid variants in tomato plants

Directory of Open Access Journals (Sweden)

Charith Raj Adkar-Purushothama

2015-12-01

Full Text Available In order to analyze the production of small RNA (sRNA by viroids upon infecting the plants, the tomato plants (Solanum lycopersicum cultivar Rutgers were inoculated with the variants of Potato spindle tuber viroid (PSTVd. After 21-days of postinoculation, total RNA was extracted and subjected for deep-sequencing using Illumina HiSeq platform. The primers were trimmed and only 21- to 24-nt long sRNAs were filtered after quality check of the raw data. The filtered sRNA population was then mapped against both the genomic (+ and antigenomic (− strands of the respective PSTVd variants using standard pattern-matching algorithm. The profiling of viroid derived sRNA (vd-sRNA revealed that the viroids are susceptible to host RNA silencing mechanism. High-throughput sequence data linked to this project have been deposited in the Gene Expression Omnibus (GEO database under accession number GSE69225.

Generic evaluation of small break loss-of-coolant accident behavior in Babcock and Wilcox designed 177-FA operating plants

International Nuclear Information System (INIS)

1980-01-01

Slow system depressurization resulting from small break loss-of-coolant accidents (LOCAs) in the reactor coolant system have not, until recently, received detailed analytical study comparable to that devoted to large breaks. Following the TMI-2 accident, the staff had a series of meetings with Babcock and Wilcox (B and W) and the B and W licensees. The staff requested that B and W and the licensees: (1) systematically evaluate plant response for small break loss-of-coolant accidents; (2) address each of the concerns documented in the Michelson report; (3) validate the computer codes used against the TMI-2 accident; (4) extend the break spectrum analysis to very small breaks, giving special consideration to failure of pressurizer valves to close; (5) analyze degraded conditions where AFW is not available; (6) prepare design changes aimed at reducing the probability of loss-of-coolant accidents produced by the failure of a PORV to close; and (7) develop revised emergency procedures for small breaks. This report describes the review of the generic analyses performed by B and W based on the requests stated above

A unique resource mutualism between the giant Bornean pitcher plant, Nepenthes rajah, and members of a small mammal community.

Directory of Open Access Journals (Sweden)

Melinda Greenwood

Full Text Available The carnivorous pitcher plant genus Nepenthes grows in nutrient-deficient substrates and produce jug-shaped leaf organs (pitchers that trap arthropods as a source of N and P. A number of Bornean Nepenthes demonstrate novel nutrient acquisition strategies. Notably, three giant montane species are engaged in a mutualistic association with the mountain treeshrew, Tupaia montana, in which the treeshrew defecates into the pitchers while visiting them to feed on nectar secretions on the pitchers' lids.Although the basis of this resource mutualism has been elucidated, many aspects are yet to be investigated. We sought to provide insights into the value of the mutualism to each participant. During initial observations we discovered that the summit rat, R. baluensis, also feeds on sugary exudates of N. rajah pitchers and defecates into them, and that this behavior appears to be habitual. The scope of the study was therefore expanded to assess to what degree N. rajah interacts with the small mammal community.We found that both T. montana and R. baluensis are engaged in a mutualistic interaction with N. rajah. T .montana visit pitchers more frequently than R. baluensis, but daily scat deposition rates within pitchers do not differ, suggesting that the mutualistic relationships are of a similar strength. This study is the first to demonstrate that a mutualism exists between a carnivorous plant species and multiple members of a small mammal community. Further, the newly discovered mutualism between R. baluensis and N. rajah represents only the second ever example of a multidirectional resource-based mutualism between a mammal and a carnivorous plant.

Prospects for the utilization of small nuclear plants for civil ships, floating heat and power stations and power seawater desalination complexes

International Nuclear Information System (INIS)

Polunichev, V.I.

2000-01-01

Small power nuclear reactor plants developed by OKB Mechanical Engineering are widely used as propulsion plants in various civil ships. Russia is the sole country in the world that possesses a powerful icebreaker and transport fleet which offers effective solution for vital socio-economic tasks of Russia's northern regions by maintaining a year-round navigation along the Arctic sea route. In the future, intensification of freighting volumes is expected in Arctic seas and at estuaries of northern rivers. Therefore, further replenishment of nuclear-powered fleet is needed by new generation ice-breakers equipped with advanced reactor plants. Adopted progressive design and technology solutions, reliable equipment and safety systems being continuously perfected on the basis of multi year operation experience feedback, addressing updated safety codes and achievement of science and technology, allow the advanced propulsion reactor plants of this type to be recommended as energy sources for floating heat and power co-generation stations and power-seawater desalination complexes. (author)

Nuclear reactor plant with a small gas-cooled HT reactor accommodated in a steel pressure vessel

International Nuclear Information System (INIS)

Schoening, J.; Elter, C.

1986-01-01

The plant has a small HT reactor and an He/He heat exchanger situated above this, with preferably two parallel circulating blowers connected after it. It also has at least one post-shutdown heat removal system, which is situated after the He/He heat exchanger in the direction of flow and which always has the total quantity of primary helium flowing through it. In one version of the design, the heat exchanger consists of two concentric bundles of helices connected after one another, which have primary helium flowing in one direction and secondary helium in the opposite direction. (orig./HP) [de

Project of SVBR-75/100 reactor plant with improved safety for nuclear sources of small and medium power

International Nuclear Information System (INIS)

Dragunov, Yu. G.; Stepanov, V. S.; Klimov, N. N.; Dedul, A. V.; Bolvanchikov, S. N.; Zrodnikov, A. V.; Tolhinsky, G. I.; Komlev, O. G.

2004-01-01

As a result of the joint work performed recently by FSUE OKB Gidropress, SNC RF-IPPE and other organizations the technical feasibility is shown for creation and usage in nuclear power engineering of the unified reactor plant (RP) SVBR-75/100 with fast neutron reactor core and lead-bismuth coolant (LBC) in the primary circuit. Technical design of SVBR-75/100 reactor plant is based on the following: 50-year operation experience in development and operation of RP with LBC for nuclear submarines; experience in development and operation of fast reactor with sodium coolant; experience in optimization of LBC technology at nuclear submarines and ground-based test benches; conceptual design of SVBR-75 reactor plant (for renovation of Units 2, 3 and 4 of Novovoronezh NPP). Technical solutions laid down in the basis of SVBR-75/100 reactor plant design are oriented towards the industrial basis, structural materials existing in Russia, as well as the unique LBC technology with experimental and practical support. The concept of SVBR-75/100 reactor plant safety assurance is based on the following provisions: maximum usage of inherent safety supported by physical features of fast neutron reactor, chemically inert LBC in the primary circuit, integral layout and special design solutions; maximum possible combination of normal operation and safety functions in RP systems. Small power of SVBR-75/100 RP makes it possible to manufacture the complete set of RP main equipment at the factory and delivery it to NPP site as-finished practically using any transport including railway. Possible fields of application of SVBR-75/100 reactor plants: modular NPPs of different power; renovation of NPPs with light water reactors exhausted their service life; independent nuclear power sources for different applications (ground-based nuclear water-desalinating plants, etc. )(author)

Small Hydropower Plants in Pomerania: The Example of Evolution of Modern Industrial Brick Architecture

Science.gov (United States)

Macikowski, Bartosz

2017-10-01

Modernism is usually recognized and associated with the aesthetics of the International Style, represented by white-plastered, horizontally articulated architecture with skimpy decoration, where function was the main imperative of the architects’ ambitions. In Northern Europe though, Modernism also revealed its brick face, representing different manners, styles, and appearances. The brick face of Modernism reflected, in fact, the complexity of the modern change, breaking ties with the historic styles of the 19th century and being still present in the beginning of the 20th century. Regardless of the cosmopolitan character of the International Style and its unified aesthetics, architects tried to find and keep shades of individuality. This was especially visible in the references to either regional or even local traditions. This diversity of modernistic architecture is intensified by its different functions. The language of industrial architecture derives its forms directly from its nature of pure functional idiom, devoted to economic and functional optimization. The industrial form usually seems subordinate to the technical nature of objects. But regardless of that, in the 19th century and the first half of the 20th century we can observe an interesting evolution of styles and tendencies in industrial architecture, even in such a narrow and specific field like the architecture of small hydropower plants. The purpose of the research was to recognize the evolution of the architectural form of hydropower plants as a developing branch of industry in the first half of the 20th century. In Pomerania, during this period, a dynamic growth of investments took place, which concerned the use of the Pomeranian rivers’ potential to produce electric energy. At the end of the 19th century, electricity had a strong meaning as a symbol of a radical civilizational change, which influenced also the aesthetic aspects of architecture. This could suggest that the architecture of

Gasification Plant Cost and Performance Optimization

Energy Technology Data Exchange (ETDEWEB)

Samuel Tam; Alan Nizamoff; Sheldon Kramer; Scott Olson; Francis Lau; Mike Roberts; David Stopek; Robert Zabransky; Jeffrey Hoffmann; Erik Shuster; Nelson Zhan

2005-05-01

As part of an ongoing effort of the U.S. Department of Energy (DOE) to investigate the feasibility of gasification on a broader level, Nexant, Inc. was contracted to perform a comprehensive study to provide a set of gasification alternatives for consideration by the DOE. Nexant completed the first two tasks (Tasks 1 and 2) of the ''Gasification Plant Cost and Performance Optimization Study'' for the DOE's National Energy Technology Laboratory (NETL) in 2003. These tasks evaluated the use of the E-GAS{trademark} gasification technology (now owned by ConocoPhillips) for the production of power either alone or with polygeneration of industrial grade steam, fuel gas, hydrocarbon liquids, or hydrogen. NETL expanded this effort in Task 3 to evaluate Gas Technology Institute's (GTI) fluidized bed U-GAS{reg_sign} gasifier. The Task 3 study had three main objectives. The first was to examine the application of the gasifier at an industrial application in upstate New York using a Southeastern Ohio coal. The second was to investigate the GTI gasifier in a stand-alone lignite-fueled IGCC power plant application, sited in North Dakota. The final goal was to train NETL personnel in the methods of process design and systems analysis. These objectives were divided into five subtasks. Subtasks 3.2 through 3.4 covered the technical analyses for the different design cases. Subtask 3.1 covered management activities, and Subtask 3.5 covered reporting. Conceptual designs were developed for several coal gasification facilities based on the fluidized bed U-GAS{reg_sign} gasifier. Subtask 3.2 developed two base case designs for industrial combined heat and power facilities using Southeastern Ohio coal that will be located at an upstate New York location. One base case design used an air-blown gasifier, and the other used an oxygen-blown gasifier in order to evaluate their relative economics. Subtask 3.3 developed an advanced design for an air

Generic evaluation of feedwater transients and small break loss-of-coolant accidents in combustion engineering designed operating plants

International Nuclear Information System (INIS)

1980-01-01

The purpose of this report is to summarize the results of a generic evaluation of feedwater transients, small break loss-of-coolant accidents (LOCAs), and other TMI-2-related events in the Combustion Engineering (CE)-designed operating plants and to establish or confirm the bases for their continued operation. The results of this evaluation are presented in this report in the form of a set of findings and recommendations in each of the principal review areas

Study on the Potential of Rice Straws as a Supplementary Fuel in Very Small Power Plants in Thailand

OpenAIRE

Penwadee Cheewaphongphan; Agapol Junpen; Orachorn Kamnoet; Savitri Garivait

2018-01-01

Agricultural residue is a major raw material for renewable energy production, particularly heat production, in Thailand. Meanwhile, the process-based residue, such as bagasse, rice husk, wood residue, palm fiber, palm shell, and saw dust, is used as a fuel for energy production in the agro-industry. Hence, this study is intended to assess the net potential and capacity of alternative agricultural residues, specifically rice straws, to serve as the supplementary fuel for very small power plant...

Operating Experiences with a Small-scale CHP Pilot Plant based on a 35 kWel Hermetic Four Cylinder Stirling Engine for Biomass Fuels

DEFF Research Database (Denmark)

Biedermann, F.; Carlsen, Henrik; Schoech, M.

2003-01-01

Within the scope of the RD&D project presented a small-scale CHP plant with a hermetic four cylinder Stirling engine for biomass fuels was developed and optimised in cooperation with the Technical University of Denmark, MAWERA Holzfeuerungsanlagen GesmbH, an Austrian biomass furnace and boiler...... exchanger of the Stirling engine, of the air preheater and of the entire combustion system. Furthermore, the optimisation of the pneumatic cleaning system to reduce ash deposition in the hot heat exchanger is of great relevance....... manufacturer, and BIOS BIOENERGIESYSTEME GmbH, an Austrian development and engineering company. Based on the technology developed, a pilot plant was designed and erected in Austria. The nominal electric power output of the plant is 35 kWel and the nominal thermal output amounts to approx. 220 kWth. The plant...

Small-scale biomass CHP using gasa turbines: a scoping study

International Nuclear Information System (INIS)

James, D.W.; Landen, R.

1996-01-01

Various options for small-scale (up to 250 KWe) Combined Heat and Power (CHP) plants evaluated in this scoping study. Plants using small gas turbines, and able to use biomass fuels when available are included. Three detailed case studies of small-scale biomass CHP plants are compared to match specific technical options with customer requirements. The commercial development of such biomass-fired CHP units, using gas turbines, is shown to be economically viable depending on fuel costs and the continuation of existing financial incentives. (UK)

The small hydropower plant in the old river Aare in Niedergoesgen, Switzerland; Kleinwasserkraftwerk Ballyschwelle, alte Aare, Niedergoesgen. Vorprojekt

Energy Technology Data Exchange (ETDEWEB)

Eichenberger, P.

2007-07-15

This preliminary project for the Swiss Federal Office of Energy (SFOE) presents a project which proposes the construction of a new small hydro plant in Niedergoesgen/Gretzenbach, Switzerland, that is to make use of the waters of the old river Aare. The project proposes the construction of a new, 350 kW plant at the site of an existing sill across the old river that originally formed part of a water-power installation given up in 1917. The existing parts of the old installation are described and the legal situation concerning water rights and land ownership are examined. Three variants for a new installation are described. Technical figures and energy-production estimates for a new installation are discussed. Ecological aspects are examined, as are the recreational aspects of the river at this location. Cost estimates and economic viability are discussed.

Economic targets for small PWR reactor designs

International Nuclear Information System (INIS)

Board, J.

1991-01-01

Small reactors are likely to be less economic than large reactors, but the lower financial exposure with small reactors may be attractive to utilities contemplating a restart to a nuclear programme. New nuclear plant can be economic, but success will depend more on how the plant are built, rather than what type or size is built. A target for new plant for operation early in the next century should be a generation cost of 3p to 3.5 p/kWh. This corresponds to an overnight capital cost of Pound 1000/kWh to Pound 1100/kWh. (author)

Effect of arbuscular mycorrhizal fungi on the potential of three wild plant species for phytoextraction of mercury from small-scale gold mine tailings

Directory of Open Access Journals (Sweden)

A. Fiqri

2016-04-01

Full Text Available A study that was aimed to explore the effects of arbuscular mycorrhizal (AM fungi inoculation on the potential of wild plant species (Paspalum conjugatum, Cyperus kyllingia, and Lindernia crustacea for phytoextraction of mercury from small-scale gold mine tailings was conducted in a glasshouse. Each of the plant seedlings was planted in a plastic pot containing 10 kg of planting medium (mixture of tailings and compost; 50%: 50% by weight. Treatments tested were three plant species and doses of AM fungi inoculation, i.e. 0 and 30 spores/plant. At harvest of 63 days, plant shoot and root were analyzed for mercury concentration. The remaining planting media in the pots were used for growing maize for 84 days. The results showed that the most potential plant species for phytoextraction of mercury was Paspalum conjugatum, while the most mercury tolerant plant was Cyperus kyllingia. Without AM fungi inoculation, the highest accumulation of mercury (44.87 mg/kg was found in the root of Paspalum conjugatum. If AM fungi were inoculated, the highest accumulation of mercury (56.30 mg/kg was also found in the shoot of Paspalum conjugatum. Results of the second experiment proved that the growth and biomass production of maize after mycophytoextraction by the plant species were higher than those of maize grown on media without mycophytoextraction of mercury.

Effects of small hydropower plants on mercury concentrations in fish.

Science.gov (United States)

Cebalho, Elaine C; Díez, Sergi; Dos Santos Filho, Manoel; Muniz, Claumir Cesar; Lázaro, Wilkinson; Malm, Olaf; Ignácio, Aurea R A

2017-10-01

Although the impacts of large dams on freshwater biota are relatively well known, the effects of small hydropower plants (SHP) are not well investigated. In this work, we studied if mercury (Hg) concentrations in fish rise in two tropical SHP reservoirs, and whether similar effects take place during impoundment. Total Hg concentrations in several fish species were determined at two SHP in the Upper Guaporé River basin floodplain, Brazil. In total, 185 specimens were analysed for Hg content in dorsal muscle and none of them reported levels above the safety limit (500 μg kg -1 ) for fish consumption recommended by the World Health Organisation (WHO). The highest levels of Hg (231 and 447 μg kg -1 ) were found in carnivorous species in both reservoirs. Mercury increased as a function of standard length in most of the fish populations in the reservoirs, and higher Hg concentrations were found in fish at the reservoir compared with fish downstream. The high dissolved oxygen concentrations and high transparency of the water column (i.e. oligotrophic reservoir) together with the absence of thermal stratification may explain low Hg methylation and low MeHg levels found in fish after flooding. Overall, according to limnological characteristics of water, we may hypothesise that reservoir conditions are not favourable to high net Hg methylation.

Development of a method to assess regional effects of developing small hydroelectric power plants in the county of Nordland; Utvikling av metodikk for analyse av sumvirkninger for utbygging av smaa kraftverk i Nordland. Forprosjekt naturmiljoe

Energy Technology Data Exchange (ETDEWEB)

Erikstad, L.; Hagen, D.; Evju, M.; Bakkestuen, V.

2009-09-15

Small hydroelectric power plants are defined as power plants with maximum effect of 10MV, normally without the need for water reservoirs. It is an increasing interest in developing small power plants. The development is regarded as environmental friendly mainly because it is renewable and non-polluting. Building of power plants do, however, impact nature through technical encroachment. In some areas there is a high density of suggested projects. This raises the need to assess effects on a larger scale than one and each project alone. The report contains an analysis of how series of projects can affect the natural environment. It is based on a defined resource specification on 1432 objects in the county of Nordland. These are compared with the modeled distribution on selected and relevant nature types where steep river beds, gorges and northerly wooded hill slopes are the most important. The analysis focuses on the sum of effects on local natural values. Values of regional and national importance are dealt with according to national procedures and is not the issue of this report. The developed method has five stages: Scoping; Analysis of natural values and vulnerability; Local and regional effects of small power plants; Assessment of mitigation possibilities; How the result can improve the planning procedure for small power plants. Development of small power plants in Nordland affects nature types that are important to the natural character of Nordland. The largest potential for negative effects is linked to additional technical encroachments (roads etc.) in untouched valley- and fjord landscapes. A greater focus on mitigation and alternative technical solutions are important to avoid these problems. (Author)

Estimation of thawing cryolithic area with numerical modeling in 3D geometry while exploiting underground small nuclear power plant

Directory of Open Access Journals (Sweden)

Melnikov N. N.

2016-03-01

Full Text Available The paper presents results on 3D numerical calculation of a thermal task related to assessing a thawing area when placing modules with reactor and steam-turbine facility of a small nuclear power plant in thickness of permafrost rocks. The paper discusses influence of the coefficient of thermal conductivity for large-scaled underground excavations lining and cryolithic area porosity on thawing depth and front movement velocity under different spatial directions

Break spectrum analyses for small break loss of coolant accidents in a RESAR-3S Plant

International Nuclear Information System (INIS)

Fletcher, C.D.; Kullberg, C.M.

1986-03-01

A series of thermal-hydraulic analyses were performed to investigate phenomena occurring during small break loss-of-coolant-accident (LOCA) sequences in a RESAR-3S pressurized water reactor. The analysis included simulations of plant behavior using the TRAC-PF1 and RELAP5/MOD2 computer codes. Series of calculations were performed using both codes for different break sizes. The analyses presented here also served an audit function in that the results shown here were used by the US Nuclear Regulatory Commission (NRC) as an independent confirmation of similar analyses performed by Westinghouse Electric Company using another computer code. 10 refs., 62 figs., 14 tabs

Evaluation of mercury pollution in cultivated and wild plants from two small communities of the Tapajós gold mining reserve, Pará State, Brazil.

Science.gov (United States)

Egler, Silvia G; Rodrigues-Filho, Saulo; Villas-Bôas, Roberto C; Beinhoff, Christian

2006-09-01

This study examines the total Hg contamination in soil and sediments, and the correlation between the total Hg concentration in soil and vegetables in two small scale gold mining areas, São Chico and Creporizinho, in the State of Para, Brazilian Amazon. Total Hg values for soil samples for both study areas are higher than region background values (ca. 0.15 mg/kg). At São Chico, mean values in soils samples are higher than at Creporizinho, but without significant differences at alpha1 in all of São Chico's produce samples, soil-plant parts regression were not significant, and Hg uptake probably occurs through stomata by atmospheric mercury deposition. Wild plants aboveground:root ratios were <1 at both study areas, and soil-plant parts regressions were significant in samples of Creporizinho, suggesting that they function as an excluder. The average total contents of Hg in edible parts of produces were close to FAO/WHO/JECFA PTWI values in São Chico area, and much lower in Creporizinho. However, Hg inorganic small gastrointestinal absorption reduces its adverse health effects.

Design of a small scale stand-alone solar thermal co-generation plant for an isolated region in Egypt

International Nuclear Information System (INIS)

Abdelhady, Suzan; Borello, Domenico; Tortora, Eileen

2014-01-01

Highlights: • In the selected area, connection to the grid is very difficult and expensive. • The integrated unsteady CSP/ORC system, was modeled TRNSYS. • Assuming a CSP of 200,000 m 2 , 6 MW e and 21.5 MW th can be obtained. • The energy is sufficient to feed more than 3,300 rural users and two big factories. • PER = 1.43, LCOE = 1.25 USD/kW h and the GHG emissions are reduced of 7300 toe/year. - Abstract: Most of Egypt’s population is concentrated in the Nile Valley (5% of Egypt’s area), while the western desert occupies an area of 50% of the total area of Egypt with a small number of inhabitants. The New Valley is the largest governorates in Egypt which occupies 45.8% of the total area of the Country and 65% of the Western Desert and it is the least densely populated governorate in Egypt. However, New Valley has started to receive the migrated people from the Nile valley and Delta region and the demand for the energy is continuously increasing. However, the rural area in New Valley still suffers from lack of access to energy services. The very high transmission losses and costs are the main challenges for electrification in this area. Then, it is worth to investigate the opportunities for distributed energy generation. This area of Egypt receives some of the highest solar radiation in the world (up to 3000 kW h per square meters per year), making it a prime location for use of this resource. In this study, performance and economic assessment of a small scale stand-alone solar thermal co-generation plant using diathermic oil is presented. This configuration is considered as a promising and sustainable solution to provide electricity and heat to an isolated area satisfying the local loads. Parabolic trough plant has been modeled in TRNSYS simulation environment integrated with the Solar Thermal Electric Components (STEC) model library. Both solar and power cycle performances have been modeled based on the solar energy data of the plant site. The

Going Large or Going Small in Plant Design: Comparison between a P.P. with three small Kaplan turbines and a P.P. with just one Large Kaplan turbine

Science.gov (United States)

Castro-Otero, C.

2017-04-01

Very often small turbine manufacturers are requested to produce sizeable turbines, too large in terms of physical dimensions, power or designing capacity. In these cases clever alternative solutions should be found to meet customers’ needs. For instance: in the old times twin runner Francis turbines were an option instead of one large machine, or if a too large Pelton turbine cannot be manufactured or designed, a good option is to install a medium size Francis and a small Pelton. Likewise, a similar approach needs to be taken should the manufacturer be asked for a too large Kaplan. Facing this situation a good option is to install three or more small Kaplan turbines. This particular case was studied in depth and after all the considerations had been made, the following question arouse: Is this a way out for the manufacturer or is it really the best option for the customer? The choice made as a way out for the manufacturer became the best option for the customer and a success for both parties. This paper aims to encourage developers and engineering firms to search for more options than the traditional one to find the best option in plant design.

Plant community variability on a small area in southeastern Montana

Science.gov (United States)

James G. MacCracken; Daniel W. Uresk; Richard M. Hansen

1984-01-01

Plant communities are inherently variable due to a number of environmental and biological forces. Canopy cover and aboveground biomass were determined for understory vegetation in plant communities of a prairie grassland-forest ecotone in southeastern Montana. Vegetation units were described using polar ordination and stepwise discriminant analysis. Nine of a total of...

Small hydropower and rural electrification in China

Energy Technology Data Exchange (ETDEWEB)

Li Ying [Ministry of Water Resources, Beijing (China). Dept. of Hydropower and Rural Electrification

1995-07-01

This document presents the status of the using small hydroelectric power plants (SHP) and rural electrification in China. The document approaches the general profile, role of small hydroelectric power plants in rural electrification and energy supply, background and factors back-sopping the fast development of SHP, concentrating on resources, SHP combined with water conservancy projects, policies and strategies, development of appropriate technology, timely development of SHP equipment manufacturing, economic justification of SHP development, and future prospects.

Ambient temperature regulates the expression of a small set of sRNAs influencing plant development through NF-YA2 and YUC2.

Science.gov (United States)

Gyula, Péter; Baksa, Ivett; Tóth, Tamás; Mohorianu, Irina; Dalmay, Tamás; Szittya, György

2018-06-01

Plants substantially alter their developmental program upon changes in the ambient temperature. The 21-24 nt small RNAs (sRNAs) are important gene expression regulators, which play a major role in development and adaptation. However, little is known about how the different sRNA classes respond to changes in the ambient temperature. We profiled the sRNA populations in four different tissues of Arabidopsis thaliana plants grown at 15, 21 and 27 °C. We found that only a small fraction (0.6%) of the sRNA loci are ambient temperature-controlled. We identified thermoresponsive miRNAs and identified their target genes using degradome libraries. We verified that the target of the thermoregulated miR169, NF-YA2, is also ambient temperature-regulated. NF-YA2, as the component of the conserved transcriptional regulator NF-Y complex, binds the promoter of the flowering time regulator FT and the auxin biosynthesis gene YUC2. Other differentially expressed loci include thermoresponsive phased siRNA loci that target various auxin pathway genes and tRNA fragments. Furthermore, a temperature dependent 24-nt heterochromatic siRNA locus in the promoter of YUC2 may contribute to the epigenetic regulation of auxin homeostasis. This holistic approach facilitated a better understanding of the role of different sRNA classes in ambient temperature adaptation of plants. This article is protected by copyright. All rights reserved.

Benthic invertebrate fauna, small streams

Science.gov (United States)

J. Bruce Wallace; S.L. Eggert

2009-01-01

Small streams (first- through third-order streams) make up >98% of the total number of stream segments and >86% of stream length in many drainage networks. Small streams occur over a wide array of climates, geology, and biomes, which influence temperature, hydrologic regimes, water chemistry, light, substrate, stream permanence, a basin's terrestrial plant...

Power improvement and modernization of small scale hydroelectric power plants in Brazil; Recapacitacao e modernizacao de PCH`s no Brasil

Energy Technology Data Exchange (ETDEWEB)

Nascimento, Jose Guilherme Antioga do [Departamento Nacional de Aguas e Energia Eletrica (DNAEE), Brasilia, DF (Brazil); Amaral, Cristiano Abijaode [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil)

1995-12-31

Several small scale hydroelectric power plants existing in Brazil have been abandoned due to recent projects of large scale units, however, some of than still present workable conditions. Due to that fact, several Brazilian electric power companies have been considering the possibility of modernizing such old units as an alternative for regional electric power generation. This work discusses the above mentioned issues 3 refs., 5 figs., 9 tabs.

Problems related to small electric power plants development: the Amazon region case; Problematica de desenvolvimento das PCH: o caso da regiao Amazonica

Energy Technology Data Exchange (ETDEWEB)

Fabrizy, M.P.; Maciel, F.A.A.; Luczynski, E. [Sao Paulo Univ., SP (Brazil). Programa Interunidades de Pos-Graduacao em Energia

1994-07-01

This paper compares the alternatives for the energy exploration for supplying the isolated communities of the interconnected network. The comparison is performed by weighting the viability of mini, micro and small hydroelectric power plants installation, in detriment of the Diesel generators and the expansion of the interconnected system, considering the existence of local hydrological potential.

Vaksvikelva small hydro

OpenAIRE

Loe, Daniel Aarset

2017-01-01

Norway is in constant need of renewable energy, and hydroelectric power is still the main source. A great future potential can be found in countless small rivers scattered across the country, which could be developed through small hydro projects. In the process of converting mechanical movement - flowing water - into electric energy, about 5% turns into heat. From a power plant with an annual production of 15 GWh, this means energy enough to heat approximately 30 households is lost. In my pro...

Considerations on safeguards approach for small centrifuge enrichment facilities

International Nuclear Information System (INIS)

Vicens, Hugo E.; Marzo, Marco A.; Nunes, Vitorio E.

2004-01-01

The safeguards' objectives for enrichment facilities encompass the detection of the diversion of declared nuclear material and of facility misuse. The safeguard's approach presently applied for commercial centrifuge enrichment facilities is based on the Hexa partite Project and seems not to be directly applicable to cases of small plants. Since ABACC started its operation one of the main problems faced was the application of safeguards to small centrifuge enrichment plants for testing centrifuges in cascade mode or for small LEU production. These plants consist of a few fully independent cascades, does not operate in a routine basis and panels prevent visual access to the centrifuges and their surroundings for preserving sensitive information. For such plants misuse scenarios seems to dominate, particularly those associated with feeding the plant with undeclared LEU. This paper presents a concise analysis of misuse strategies in small centrifuge facility and alternative safeguard's approach, describing the main control elements to be applied. The particularities arising from the existence of panels or boxes covering the centrifuges are specifically addressed. Two alternatives approaches based on the application of a transitory perimeter control to increase the effectiveness of unannounced inspection and on the application of permanent perimeter control are presented. (author)

Multinode analysis of small breaks for B and W's 205-fuel-assembly nuclear plants with internals vent valves

International Nuclear Information System (INIS)

Jones, R.C.; Dunn, B.M.; Parks, C.E.

1976-03-01

Multinode analyses were conducted for several small breaks in the reactor coolant system of B and W's 205-fuel-assembly nuclear plants with internals vent valves. The multinode blowdown code CRAFT was used to evaluate the hydrodynamics and transient water inventories of the reactor coolant system. The FOAM code was used to compute a swell level history for the core, and the THETA1-B code was used to perform transient fuel pin thermal calculations. Curves showing the parameters of interest are presented. The results are well within the Final Acceptance Criteria

Multinode analysis of small breaks for B and W's 145-fuel-assembly nuclear plants with internals vent valves

International Nuclear Information System (INIS)

Parks, C.E.; Allen, R.J.; Cartin, L.R.

1976-03-01

Multinode analyses were conducted for several small breaks in the reactor coolant system of B and W's 145 fuel-assembly nuclear plants with internals vent valves. The multinode blowdown code CRAFT was used to evaluate the hydrodynamics and transient water inventories of the reactor coolant system. The FOAM code was used to compute a swell level history for the core, and the THETA1-B code was used to perform transient fuel pin thermal calculations. Curves showing the parameters of interest are presented. These results are well within the Final Acceptance Criteria

Staffing requirements for future small and medium reactors based on projections in the Russian Federation

International Nuclear Information System (INIS)

Antonovsky, G.M.; Kodochigov, N.G.; Kurachenkov, A.V.; Novikov, V.V.

2001-01-01

Experimental Design Bureau of Mechanical Engineering (OKBM) specializes in the development of small and medium power reactors having different purposes. They include reactor plants for NPHPP, nuclear district heating power plants and propulsion plants. Small and medium power plants have simpler processes of electricity and heat production, less systems, simpler control algorithms and considerably enhanced inherent safety properties. These plants are mainly equipped with passive safety systems. These properties are especially characteristic for reactor plants of nuclear district heating power plants and HTG reactor plants. The designs of small and medium power plants actually provide a high degree of control automation which considerably reduces workload on the personnel in both normal and abnormal operation conditions. All this allows the reduction in personnel for small and medium power reactors if compared to high capacity reactor plants. But due to objective reasons the specific number of personnel (man/MW) for average and especially small capacity reactors considerably exceeds the value for high capacity reactor plants. At the same time one can propose a set of organization - technical measures allowing the increase in this value in future. Safety requirements imposed for small and average capacity reactors are the same or more strict than those for high capacity reactors. That's why the requirements to the training of personnel for such reactor plants are not allowed to be lowered if compared to the requirements imposed to the personnel of high capacity reactors. (author)

Small and medium reactors: Development status and application aspects

International Nuclear Information System (INIS)

Kupitz, J.

2001-01-01

During the 1960s and the early 1970s. the nuclear power plants entering service were dominated by plants with outputs falling into the small (less than 150 W e ) and medium (300 MWe to 700 MWe) reactor size ranges. During the late 1970s and 1980s, the balance shifted to large size plants (900 MWe to 1400 MWe), as nuclear power plants entered service, predominately, to serve the requirements of industrialized countries such as the US, Japan, Germany, and France. However, in the 1990s, the pendulum has swung back in the direction of small and medium sized reactors; currently 65% of the nuclear power plants under construction fall into the small and medium reactor size ranges. This shift has resulted from a sharp reduction in the number of nuclear power plants being built in the industrialized countries, in combination with the continued construction of small and medium sized nuclear power plants in developing countries such as India. China, Pakistan, and Slovakia. Developing countries are often characterized by limited capacity electrical grid systems. limited financial capability, and rapidly expanding energy demand requirements. In addition, most of the developing countries in which rapid increases in population and energy demand are occurring have few or very limited indigenous energy resources. These countries are therefore very interested in acquiring energy sources (for electricity production and process heat) that can serve the needs of their people and industries, and which do not overburden their financial capabilities (balance of payments, national debt load. etc.). It is therefore not surprising that many developing countries have, particularly during the late 1990s, expressed an interest in small and medium sized nuclear power plants (SMRs). The requirements for SMRs often cited by developing countries include low absolute capital cost, short construction schedule, favourable economic operation, and infrastructure requirements within the technical and

Small mammals as components of the consumer subsystem

International Nuclear Information System (INIS)

French, N.R.

1978-01-01

The trophic and species composition of small mammal populations in various environments are related to structural complexity of the plant community. The basis for these relationships is in energetics, abundance, and dependability of food resources determining the potential patterns of exploitation possible. There is evidence for resource partitioning by small mammals in grasslands, but development of suitable strategies are dependent upon demographic characteristics. Energetic efficiency of small mammals and invertebrates is examined as it affects their relative success as consumers in grasslands. The relative importance of small mammals, birds, and arthropods in relation to utilization of plant herbage, seeds, and invertebrate food resources is estimated for five grassland sites. Recommendations are made for topics meriting further investigation

Post-cracking behavior of blocks, prisms, and small concrete walls reinforced with plant fiber

Directory of Open Access Journals (Sweden)

I. I. Soto

Full Text Available Structural masonry using concrete blocks promotes the rationalization of construction projects, lowering the final cost of a building through the elimination of forms and the reduction of the consumption of reinforcement bars. Moreover, production of a block containing a combination of concrete and vegetable fiber sisal results in a unit with properties such as mechanical strength, stiffness, flexibility, ability to absorb energy, and post-cracking behavior that are comparable to those of a block produced with plain concrete. Herein are reported the results of a study on the post-cracking behavior of blocks, prisms, and small walls reinforced with sisal fibers (lengths of 20 mm and 40 mm added at volume fractions of 0.5% and 1%. Tests were performed to characterize the fibers and blocks and to determine the compressive strength of the units, prisms, and small walls. The deformation modulus of the elements was calculated and the stress-strain curves were plotted to gain a better understanding of the values obtained. The compression test results for the small walls reinforced with fibers were similar to those of the reference walls and better than the blocks and prisms with added fibers, which had resistances lower than those of the corresponding conventional materials. All elements prepared with the addition of sisal exhibited an increase in the deformation capacity (conferred by the fibers, which was observed in the stress-strain curves. The failure mode of the reference elements was characterized by an abrupt fracture, whereas the reinforced elements underwent ductile breakage. This result was because of the presence of the fibers, which remained attached to the faces of the cracks via adhesion to the cement matrix, thus preventing loss of continuity in the material. Therefore, the cement/plant fiber composites are advantageous in terms of their ductility and ability to resist further damage after cracking.

Bacillus coagulans GBI-30, 6086 increases plant protein digestion in a dynamic, computer-controlled in vitro model of the small intestine (TIM-1).

Science.gov (United States)

Keller, D; Van Dinter, R; Cash, H; Farmer, S; Venema, K

2017-05-30

The aim of this study was to assess the potential of the probiotic Bacillus coagulans GBI-30, 6086 [GanedenBC 30 ] (BC30) to aid in protein digestion of alimentary plant proteins. To test this, three plant proteins, from pea, soy and rice, were digested in a validated in vitro model of the stomach and small intestine (TIM-1) in the absence and in the presence of BC30. Samples were taken from the TIM-1 fractions that mimic uptake of amino acids by the host and analysed for α-amino nitrogen (AAN) and total nitrogen (TN). Both were increased by BC30 for all three plant proteins sources. The ratio of TN/AAN indicated that for pea protein digestion was increased by BC30, but the degree of polymerisation of the liberated small peptides and free amino acids was not changed. For soy and rice, however, BC30 showed a 2-fold reduction in the TN/AAN ratio, indicating that the liberated digestion products formed during digestion in the presence of BC30 were shorter peptides and more free amino acids, than those liberated in the absence of BC30. As BC30 increased protein digestion and uptake in the upper gastrointestinal (GI) tract, it consequently also reduced the amount of protein that would be delivered to the colon, which could there be fermented into toxic metabolites by the gut microbiota. Thus, the enhanced protein digestion by BC30 showed a dual benefit: enhanced amino acid bioavailability from plant proteins in the upper GI tract, and a healthier environment in the colon.

AsHSP17, a creeping bentgrass small heat shock protein modulates plant photosynthesis and ABA-dependent and independent signalling to attenuate plant response to abiotic stress.

Science.gov (United States)

Sun, Xinbo; Sun, Chunyu; Li, Zhigang; Hu, Qian; Han, Liebao; Luo, Hong

2016-06-01

Heat shock proteins (HSPs) are molecular chaperones that accumulate in response to heat and other abiotic stressors. Small HSPs (sHSPs) belong to the most ubiquitous HSP subgroup with molecular weights ranging from 12 to 42 kDa. We have cloned a new sHSP gene, AsHSP17 from creeping bentgrass (Agrostis stolonifera) and studied its role in plant response to environmental stress. AsHSP17 encodes a protein of 17 kDa. Its expression was strongly induced by heat in both leaf and root tissues, and by salt and abscisic acid (ABA) in roots. Transgenic Arabidopsis plants constitutively expressing AsHSP17 exhibited enhanced sensitivity to heat and salt stress accompanied by reduced leaf chlorophyll content and decreased photosynthesis under both normal and stressed conditions compared to wild type. Overexpression of AsHSP17 also led to hypersensitivity to exogenous ABA and salinity during germination and post-germinative growth. Gene expression analysis indicated that AsHSP17 modulates expression of photosynthesis-related genes and regulates ABA biosynthesis, metabolism and ABA signalling as well as ABA-independent stress signalling. Our results suggest that AsHSP17 may function as a protein chaperone to negatively regulate plant responses to adverse environmental stresses through modulating photosynthesis and ABA-dependent and independent signalling pathways. © 2015 John Wiley & Sons Ltd.

A Method to Quantify Plant Availability and Initiating Event Frequency Using a Large Event Tree, Small Fault Tree Model

International Nuclear Information System (INIS)

Kee, Ernest J.; Sun, Alice; Rodgers, Shawn; Popova, ElmiraV; Nelson, Paul; Moiseytseva, Vera; Wang, Eric

2006-01-01

South Texas Project uses a large fault tree to produce scenarios (minimal cut sets) used in quantification of plant availability and event frequency predictions. On the other hand, the South Texas Project probabilistic risk assessment model uses a large event tree, small fault tree for quantifying core damage and radioactive release frequency predictions. The South Texas Project is converting its availability and event frequency model to use a large event tree, small fault in an effort to streamline application support and to provide additional detail in results. The availability and event frequency model as well as the applications it supports (maintenance and operational risk management, system engineering health assessment, preventive maintenance optimization, and RIAM) are briefly described. A methodology to perform availability modeling in a large event tree, small fault tree framework is described in detail. How the methodology can be used to support South Texas Project maintenance and operations risk management is described in detail. Differences with other fault tree methods and other recently proposed methods are discussed in detail. While the methods described are novel to the South Texas Project Risk Management program and to large event tree, small fault tree models, concepts in the area of application support and availability modeling have wider applicability to the industry. (authors)

A biological small sewage treatment plant without outside power supply. Eine biologische Hausklaeranlage ohne Fremdenergie

Energy Technology Data Exchange (ETDEWEB)

Renner, H [Technische Univ., Graz (Austria). Inst. fuer Siedlungs- und Industriewasserwirtschaft, Flussbau und Landwirtschaftlichen Wasserbau; Voigtlaender, G [Hochschule fuer Architektur und Bauwesen, Weimar (German Democratic Republic). Wissenschaftsbereich Versorgungsanlagen; Lopp, H [VEB Kombinat Wassertechnik und Projektierung Wasserwirtschaft (KWP), Halle (German Democratic Republic)

1989-07-01

The paper presented deals with the development of a small sewage treatment plant operating without supply of energy. Purification of sewage is achieved in a three-step process: Sedimentation tank, anaerobic reactor and aerobic reactor. The efficiency of the anaerobic reactor - as against the efficiency of a common septic tank - is significantly increased by arranging a number of plates in the reactor, on which anaerobic biomass can grow. Further degradation of sewage compounds and nitrification - also effected by adhering microorganisms - occurs in the aerobic biomass are made of a semipermeable plastic film and arranged in such a way as to ensure simultaneous supply of oxygen needed by aerobic organism. The paper reports the results of investigations under laboratory conditions as well as results - available so far - or investigations in technical scale. (orig.).

Small reactors and the 'second nuclear era'

International Nuclear Information System (INIS)

Egan, J.R.

1984-01-01

Predictions of the nuclear industry's demise are premature and distort both history and politics. The industry is reemerging in a form commensurate with the priorities of those people and nations controlling the global forces of production. The current lull in plant orders is due primarily to the world recession and to factors related specifically to reactor size. Traditional economies of scale for nuclear plants have been greatly exaggerated. Reactor vendors and governments in Great Britain, France, West Germany, Japan, the United States, Sweden, Canada, and the Soviet Union are developing small reactors for both domestic applications and export to the Third World. The prefabricated, factory-assembled plants under 500 MWe may alleviate many of the existing socioeconomic constraints on nuclear manufacturing, construction, and operation. In the industrialized world, small reactors could furnish a qualitatively new energy option for utilities. But developing nations hold the largest potential market for small reactors due to the modest size of their electrical systems. These units could double or triple the market potential for nuclear power in this century. Small reactors will both qualitatively and quantitatively change the nature of nuclear technology transfers, offering unique advantages and problems vis-a-vis conventional arrangements. (author)

A composite efficiency metrics for evaluation of resource and energy utilization

International Nuclear Information System (INIS)

Yang, Siyu; Yang, Qingchun; Qian, Yu

2013-01-01

Polygeneration systems are commonly found in chemical and energy industry. These systems often involve chemical conversions and energy conversions. Studies of these systems are interdisciplinary, mainly involving fields of chemical engineering, energy engineering, environmental science, and economics. Each of these fields has developed an isolated index system different from the others. Analyses of polygeneration systems are therefore very likely to provide bias results with only the indexes from one field. This paper is motivated from this problem to develop a new composite efficiency metrics for polygeneration systems. This new metrics is based on the second law of thermodynamics, exergy theory. We introduce exergy cost for waste treatment as the energy penalty into conventional exergy efficiency. Using this new metrics could avoid the situation of spending too much energy for increasing production or paying production capacity for saving energy consumption. The composite metrics is studied on a simplified co-production process, syngas to methanol and electricity. The advantage of the new efficiency metrics is manifested by comparison with carbon element efficiency, energy efficiency, and exergy efficiency. Results show that the new metrics could give more rational analysis than the other indexes. - Highlights: • The composite efficiency metric gives the balanced evaluation of resource utilization and energy utilization. • This efficiency uses the exergy for waste treatment as the energy penalty. • This efficiency is applied on a simplified co-production process. • Results show that the composite metrics is better than energy efficiencies and resource efficiencies

Plant aquaporins: roles in plant physiology.

Science.gov (United States)

Li, Guowei; Santoni, Véronique; Maurel, Christophe

2014-05-01

Aquaporins are membrane channels that facilitate the transport of water and small neutral molecules across biological membranes of most living organisms. Here, we present comprehensive insights made on plant aquaporins in recent years, pointing to their molecular and physiological specificities with respect to animal or microbial counterparts. In plants, aquaporins occur as multiple isoforms reflecting a high diversity of cellular localizations and various physiological substrates in addition to water. Of particular relevance for plants is the transport by aquaporins of dissolved gases such as carbon dioxide or metalloids such as boric or silicic acid. The mechanisms that determine the gating and subcellular localization of plant aquaporins are extensively studied. They allow aquaporin regulation in response to multiple environmental and hormonal stimuli. Thus, aquaporins play key roles in hydraulic regulation and nutrient transport in roots and leaves. They contribute to several plant growth and developmental processes such as seed germination or emergence of lateral roots. Plants with genetically altered aquaporin functions are now tested for their ability to improve plant resistance to stresses. This article is part of a Special Issue entitled Aquaporins. Copyright © 2013 Elsevier B.V. All rights reserved.

Evaluation methods of vibration stress of small bore piping

Energy Technology Data Exchange (ETDEWEB)

Hiramatsu, Miki; Sasaki, Toru [Institute of Nuclear Safety System Inc., Mihama, Fukui (Japan)

2001-09-01

Fatigue fracture by vibration stress is one of the main causes of troubles which occur at small bore piping in nuclear power plants. Therefore at the plants they manage small bore piping using a method in which their vibration accelerations are measured and the vibration stresses are calculated. In this work, vibration tests for two sets of mock-ups simulating actual piping in the plants by sinusoidal oscillation and by that obtained at an actual plant were carried out, and then an evaluation method was developed to obtain proper value of vibration stress from the measured data by the vibration tests. In comparison of the vibration stress obtained from the measured acceleration with that directly measured using strain gauges, it is confirmed that accurate vibration stress can be evaluated by a formula in which the real center of gravity of small bore piping and the acceleration of main (system) piping are considered. (author)

New Approach to Enhance an Effect of Condition Monitoring of Mid/Small Size Rotating Equipment in Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Shin You Soo; Chang, Hee Seung [KHNP, Daejeon (Korea, Republic of)

2016-05-15

Condition monitoring for small and medium-size rotating equipment is mainly done by a patrol inspection and a vibration measurement. These methods are useful to recognize a significant change in a sound, temperature and vibration amplitude on the bearing housing. However, such a significant change shows an abnormal condition just before failure so that there is not much time to take a right action to recover. In other words, there is a severe damage when someone detects the phenomenon. These methods are good way to detect a flaw but too late to fix. It can't detect early recognition of defect To enhance the effect of condition monitoring and recognize a defect earlier, an integrated measurement including high band frequency analysis is required. It will be implemented at one of nuclear power plants in Korea as a pilot to verify an effect and applicability at nuclear power plants.

Financial risk in the small scale hydroelectric power plant in the PROINFA; Riscos financeiros em uma PCH no PROINFA

Energy Technology Data Exchange (ETDEWEB)

Alves, Jailson Jose Medeiros; Estima, Luiz Claudio Pires; Martins, Marcelo Jaques [Centrais Eletricas Brasileiras S.A. (ELETROBRAS), Rio de Janeiro, RJ (Brazil). Dept. de Engenharia de Geracao. Div. de Acompanhamentos de Empreendimentos de Geracao

2006-10-15

The current work presents the study of the involved financial risks in an enterprise of a small hydroelectric plant in the incentive program of the alternative sources of electric energy (PROINFA), The financial conditions elaborated by the government through its bilateral contracts are analyzed with the objective to stimulate the private capital to participate of the program and thus to the diversification of our energy matrix in the next years. The research has as objective to identify and to consider the financial risks where a plant incurs when participating of a program as this. For risk analysis the simulation method of Monte-Carlo was used, that is an efficient methodology for calculation of financial risks in this type's enterprises. It is shown that these contracts are very useful tools to the businesses of this sector, adding economic-financial benefits to the Brazilian energy market. (author)

The challenge of introducing HTR plants on to the international power plant market

International Nuclear Information System (INIS)

Bogen, J.; Stoelzl, D.

1987-01-01

The international power plant market today is characterized by high increase in energy consumption for developing countries with limitations of investment capital and low increase in energy consumption for industrialized countries with limitations of additional power plant capacities. As a consequence there is a low demand for large new power stations. This leads to a tendency for small and medium sized power plant units - meeting high environmental standards - for which the total investment volume is low and full load operation of a plant can be realized earlier due to the small block capacity. - For nuclear power plants the High-Temperature-Reactor (HTR)-line with spherical fuel elements and a core structure of graphite is specially suited for this small and medium sized nuclear reactor (SMSNR) capacity. The excellent safety characteristics, the high availability, the low radiation doses for the operation personnel and the environment of the HTR line has been demonstrated by 20 years of operation of the AVR-15 MWe experimental power plant in Juelich F.R.G. and since 1985 by operation of the THTR-300 MWe prototype plant at Hamm-Uentrop F.R.G. Up-dated concepts of the HTR-line are under design for electricity generation (HTR-500), for co-generation of power and heat (HTR-100) and for district heating purposes only (GHR-10). By implementing two HTR projects the Brown Boveri Group is in the position to realize the collected experiences from design, licensing, erection, commissioning and operation for the follow-on projects. This leads to practical and sound technical solutions convenient for existing manufacturing processes, well known materials, standardized components and usual manufacturing tolerances. Specific plant characteristics can be used for advantages in the competition. (author)

Co-digestion of sewage sludge from external small WWTP's in a large plant

Science.gov (United States)

Miodoński, Stanisław

2017-11-01

Improving energy efficiency of WWTPs (Waste Water Treatment Plants) is crucial action of modern wastewater treatment technology. Technological treatment process optimization is important but the main goal will not be achieved without increasing production of renewable energy from sewage sludge in anaerobic digestion process which is most often used as sludge stabilization method on large WWTP's. Usually, anaerobic digestion reactors used for sludge digestion were designed with reserve and most of them is oversized. In many cases that reserve is unused. On the other hand, smaller WWTPs have problem with management of sewage sludge due to lack of adequately developed infrastructure for sludge stabilization. Paper shows an analysis of using a technological reserve of anaerobic digestion reactors at large WWTP (1 million P.E.) for sludge stabilization collected from smaller WWTP in a co-digestion process. Over 30 small WWTPs from the same region as the large WWTP were considered in this study. Furthermore, performed analysis included also evaluation of potential sludge disintegration pre-treatment for co-digestion efficiency improvement.

Perspective on small and medium size reactors

International Nuclear Information System (INIS)

Stahlkopf, K.E.; Braun, C.

1985-01-01

There has been renewed interests in the United States in small and medium size nuclear power plants (600 MWe or less). The reasons for this include: (1) there is a large uncertainty in load growth projections. Small to medium size nuclear power plants may be better suited to meet uncertain load growth projections. (2) It has been argued that a large economy of scale exists because of the nature of nuclear power installations. A recent examination of the French program shows that no economy of scale exists between the 900 MWe and 1300 MWe plants. Others have suggested that it is possible to reduce the economy of scale so it is not a prohibitive factor. (3) In the past in the United States, it has been customary for several smaller utilities to share the output of a large nuclear plant to take advantage of the perceived economy of scale. Difficulties have been encountered by some of these enterprises. (4) An examination of capacity factors for the United States shows that plants of smaller output appear to operate more reliably and economically than larger plants

Design of novel DME/methanol synthesis plants based on gasification of biomass

DEFF Research Database (Denmark)

Clausen, Lasse Røngaard

-scale DME plants based on gasification of torrefied biomass. 2. Small-scale DME/methanol plants based on gasification of wood chips. 3. Alternative methanol plants based on electrolysis of water and gasification of biomass. The plants were modeled by using the component based thermodynamic modeling...... why the differences, in biomass to DME/methanol efficiency, between the small-scale and the large-scale plants, showed not to be greater, was the high cold gas efficiency of the gasifier used in the small-scale plants (93%). By integrating water electrolysis in a large-scale methanol plant, an almost...... large-scale DME plant) to 63%, due to the relatively inefficient electrolyser....

Cost of electricity from small scale co-generation of electricity and heat

Energy Technology Data Exchange (ETDEWEB)

Kjellstroem, Bjoern

2012-07-15

There is an increasing interest in Sweden for using also small heat loads for cogeneration of electricity and heat. Increased use of small CHP-plants with heat supply capacities from a few 100 kW(h) up to 10 MW(h) cannot change the structure of the electricity supply system significantly, but could give an important contribution of 2 - 6 TWh(e) annually. The objective of this study was to clarify under what conditions electricity can be generated in small wood fired CHP-plants in Sweden at costs that can compete with those for plants using fossil fuels or nuclear energy. The capacity range studied was 2 - 10 MW(h). The results should facilitate decisions about the meaningfulness of considering CHP as an option when new heat supply systems for small communities or sawmills are planned. At the price for green certificates in Sweden, 250 - 300 SEK/MWh(e), generation costs in small wood fired CHP-plants should be below about 775 SEK/MWh(e) to compete with new nuclear power plants and below about 925 SEK/MWh(e) to compete with generation using fossil fuels.

Abstract flexibility description for virtual power plant scheduling

OpenAIRE

Fröhling, Judith

2017-01-01

In the ongoing paradigm shift of the energy market from big power plants to more and more small and decentralized power plants, virtual power plants (VPPs) play an important role. VPPs bundle the capacities of the small and decentralized resources (DER). Planing of VPP operation, that is also called scheduling, relies on the flexibilities of controllable DER in the VPP, e.g., combined heat and power plants (CHPs), heat pumps and batteries. The aim of this thesis is the development of an abstr...

Virtual Power Plants as a Model for the Competitiveness of Small Manufacturers and Operators of Virtual Power Plants in Markets of Electricity and Gas

International Nuclear Information System (INIS)

Galic, T.; Tomsic, Z.

2012-01-01

Production of electricity from renewable energy sources and energy-efficient power sources to be connected to the electricity distribution network is still not competitive with electricity production from conventional sources of electricity. A powerful technological development of distributed energy sources and technologies for electricity storage has reduced their production costs, production costs of electricity from distributed energy sources, the costs of simultaneous production of electricity and thermal energy from cogeneration distributed energy sources and thus has facilitated their increased use in practice. It also allows them to interconnect systems such as virtual power plants in order to achieve full economic feasibility of their use. Current electricity and gas customers, now also in the role of small power producers, interconnected by virtual power plants operators, in addition to buying electricity and gas on retail markets for electricity and gas, will be able to sell electricity and new energy services also on wholesale electricity markets. Development and application of new distributed technologies will enable the production of new quantities of electricity which will increase the competitiveness of electricity producers, competitiveness of electricity suppliers of end-customers and elasticity of supply and demand in the electricity market. These processes will also increase the efficiency of the entire systems of electricity supply and of the gas supply systems.(author)

Preliminary Study of Potential Market for Small Reactors

International Nuclear Information System (INIS)

Minato, A.; Brown, N. W.

2008-01-01

Small reactors are an energy supply for a specific purpose and oriented for a different market than large reactors. Small reactors will provide a local solution for developed and developing countries, such as, in remote areas, on small grids, or for non-electricity applications such as, district heating, seawater desalination and process heat. Single or medium sized power stations with small reactors should be compared with single fissile or renewable energy source and not be compared with large reactors. CRIEPI and LLNL have studied the business opportunities for small reactors. The small reactor concept is planned for initial use in small remote communities and in developing countries with small power distribution grid. Rapid installation and simple operation of the small plants is intended to support use in these communities without requiring development of a substantial nuclear technology infrastructure. In this study, two approaches were used in the assessment of the potential market. The first approach took a global look at the need for small nuclear plants. Then selected countries and sites were identified based on countries expressing interest in small reactors to the IAEA and consideration of sites in the US and Japan. (1) Tunisia, Mexico, Indonesia, Uruguay, Egypt and Argentina have demonstrated interest in nuclear power. Selecting one of these is dependent on political and socioeconomic factors, some of which have been identified, that require direct interaction with the countries to establish if they represent real opportunities. (2) The states of Hawaii and Alaska in the United States have high power cost and remote or island communities that may benefit from small nuclear plants. Alaska has shown greater interest in power alternatives including small than Hawaii and there is clearly less public resistance to nuclear power in Alaska. (3) The countries in Central America are actively expanding their power grids but have not demonstrated great interest

Modeling and dynamic behaviour of hydropower plants

CERN Document Server

Kishor, Nand

2017-01-01

This book presents a systematic approach to mathematical modeling of different configurations of hydropower plants over four sections - modeling and simulation approaches; control of hydropower plants; operation and scheduling of hydropower plants, including pumped storage; and special features of small hydropower plants.

Energetic-economic dynamic computational analysis of plants with small capacity - Gera model

International Nuclear Information System (INIS)

Storfer, A.F.; Demanboro, A.C. de; Campello, C.A.G.B.

1990-01-01

A methodology and mathematical model for energy and economic analysis of hydroelectric power plants with low and medium capacity are presented. This methodology will be used for isolated or integrated hydroelectric power plants, including plants that part of their produced energy will go to the site market and part will go to regional electric system. (author)

Gold in plants

International Nuclear Information System (INIS)

Girling, C.A.; Peterson, P.J.

1980-01-01

Many plants have the ability to take up gold from the soil and to accumulate it in their tisssue. Advances have been made in understanding these processes to the point where their exploitation in the field of prospecting for gold appears practically feasible. Neutron activation analysis is used for the determination of the small quantities of gold in plants

Regulatory requirements for desalination plant coupled with nuclear reactor plant

International Nuclear Information System (INIS)

Yune, Young Gill; Kim, Woong Sik; Jo, Jong Chull; Kim, Hho Jung; Song, Jae Myung

2005-01-01

A small-to-medium sized reactor has been developed for multi-purposes such as seawater desalination, ship propulsion, and district heating since early 1990s in Korea. Now, the construction of its scaled-down research reactor, equipped with a seawater desalination plant, is planned to demonstrate the safety and performance of the design of the multi-purpose reactor. And the licensing application of the research reactor is expected in the near future. Therefore, a development of regulatory requirements/guides for a desalination plant coupled with a nuclear reactor plant is necessary for the preparation of the forthcoming licensing review of the research reactor. In this paper, the following contents are presented: the design of the desalination plant, domestic and foreign regulatory requirements relevant to desalination plants, and a draft of regulatory requirements/guides for a desalination plant coupled with a nuclear reactor plant

Generic evaluation of feedwater transients and small break loss-of-coolant accidents in GE-designed operating plants and near-term operating license applications

International Nuclear Information System (INIS)

1980-01-01

The results are presented of a generic evaluation of feedwater transients, small-break loss-of-coolant accidents (LOCAs), and other TMI-2-related events for General Electric Company (GE)-designed operating plants and near-term operating license applications to confirm or establish the bases for the continued safe operation of the operating plants. The results of this evaluation are presented in this report in the form of a set of findings and recommendations in each of the principal review areas. Additional review of the accident is continuing and further information is being obtained and evaluated. Any new information will be reviewed and modifications will be made as appropriate

Enhancement of micropollutant degradation at the outlet of small wastewater treatment plants.

Directory of Open Access Journals (Sweden)

Luca Rossi

Full Text Available The aim of this work was to evaluate low-cost and easy-to-operate engineering solutions that can be added as a polishing step to small wastewater treatment plants to reduce the micropollutant load to water bodies. The proposed design combines a sand filter/constructed wetland with additional and more advanced treatment technologies (UV degradation, enhanced adsorption to the solid phase, e.g., an engineered substrate to increase the elimination of recalcitrant compounds. The removal of five micropollutants with different physico-chemical characteristics (three pharmaceuticals: diclofenac, carbamazepine, sulfamethoxazole, one pesticide: mecoprop, and one corrosion inhibitor: benzotriazole was studied to evaluate the feasibility of the proposed system. Separate batch experiments were conducted to assess the removal efficiency of UV degradation and adsorption. The efficiency of each individual process was substance-specific. No process was effective on all the compounds tested, although elimination rates over 80% using light expanded clay aggregate (an engineered material were observed. A laboratory-scale flow-through setup was used to evaluate interactions when removal processes were combined. Four of the studied compounds were partially eliminated, with poor removal of the fifth (benzotriazole. The energy requirements for a field-scale installation were estimated to be the same order of magnitude as those of ozonation and powdered activated carbon treatments.

The perception of strigolactones in vascular plants.

Science.gov (United States)

Lumba, Shelley; Holbrook-Smith, Duncan; McCourt, Peter

2017-05-17

Small-molecule hormones play central roles in plant development, ranging from cellular differentiation and organ formation to developmental response instruction in changing environments. A recently discovered collection of related small molecules collectively called strigolactones are of particular interest, as these hormones also function as ecological communicators between plants and fungi and between parasitic plants and their hosts. Advances from model plant systems have begun to unravel how, as a hormone, strigolactone is perceived and transduced. In this Review, we summarize this information and examine how understanding strigolactone hormone signaling is leading to insights into parasitic plant infections. We specifically focus on how the development of chemical probes can be used in combination with model plant systems to dissect strigolactone's perception in the parasitic plant Striga hermonthica. This information is particularly relevant since Striga is considered one of the largest impediments to food security in sub-Saharan Africa.

Gene expression analyses of the small intestine of pigs in the ex-evacuation zone of the Fukushima Daiichi Nuclear Power Plant.

Science.gov (United States)

Morimoto, Motoko; Kato, Ayaka; Kobayashi, Jin; Okuda, Kei; Kuwahara, Yoshikazu; Kino, Yasushi; Abe, Yasuyuki; Sekine, Tsutomu; Fukuda, Tomokazu; Isogai, Emiko; Fukumoto, Manabu

2017-11-15

After the accident at the Fukushima Daiichi Nuclear Power Plant, radioactive contaminants were released over a widespread area. Monitoring the biological effects of radiation exposure in animals in the ex-evacuation zone should be continued to understand the health effects of radiation exposure in humans. The present study aimed to clarify the effects of radiation by investigating whether there is any alteration in the morphology and gene expressions of immune molecules in the intestine of pigs and inobuta (wild boar and domestic pig hybrid) in the ex-evacuation zone in 2012. Gene expression analysis was performed in small intestine samples from pigs, which were collected from January to February 2012, in the ex-evacuation zone. Pigs lived freely in this zone, and their small intestine was considered to be affected by the dietary intake of radioactive contaminants. Several genes were selected by microarray analysis for further investigation using real-time polymerase chain reaction. IFN-γ, which is an important inflammatory cytokine, and TLR3, which is a pattern recognize receptor for innate immune system genes, were highly elevated in these pigs. The expressions of the genes of these proteins were associated with the radiation level in the muscles. We also examined the alteration of gene expressions in wild boars 5 years after the disaster. The expression of IFN-γ and TLR3 remained high, and that of Cyclin G1, which is important in the cell cycle, was elevated. We demonstrated that some changes in gene expression occurred in the small intestine of animals in the ex-evacuation zone after radiation. It is difficult to conclude that these alterations are caused by only artificial radionuclides from the Fukushima Daiichi Nuclear Power Plant. However, the animals in the ex-evacuation zone might have experienced some changes owing to radioactive materials, including contaminated soil, small animals, and insects. We need to continue monitoring the effects of long

Small-scale hydro-power plant in Anzonico - Preliminary project; Progetto microcentrale idroelettrica, Anzonico. Programma Centrali idrauliche. Progetto di massima

Energy Technology Data Exchange (ETDEWEB)

Dotti, R. [Reali e Guscetti SA, Ambri (Switzerland); Rosselli, P. [Celio Engineering SA, Ambri (Switzerland)

2009-01-15

This report for the Swiss Federal Office of Energy (SFOE) takes a look at a project for the realisation of a small hydro-power plant in the municipality of Anzonico, southern Switzerland. The water of a small alpine stream is to be used for power generation and vineyard irrigation as well as for the creation of an additional water resource for fire fighting in this sensitive region. The report is foreseen to support the request for a water usage concession to the authorities of the Canton of Ticino. It presents details on the hydrological data for the river and the dimensioning of the installation. The hydrological installations and the turbine foreseen are described and discussed, as is the removal of river sediment. The electricity production expected is discussed, as is the economic viability of the project. Synergies exist with the local electricity utility that will renew and improve its power distribution and telecommunication system when the penstock will be mounted in the underground.

Studies of S-CO{sub 2} Power Plant Pipe Design for Small Modular Sodium-cooled Fast Reactor

Energy Technology Data Exchange (ETDEWEB)

Kim, Min Seok; Ahn, Yoon Han; Lee, Jeong Ik [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

2014-10-15

If SFR can be developed into the economical small modular reactor (SMR) for an export from Korea, the expected value can be greater. However, current SFR design may face difficulty in public acceptance due to the potential hazard from sodium-water reaction (SWR) when the current conventional steam Rankine cycle is utilized as a power conversion system for a SFR. In order to eliminate SWR, the Supercritical CO{sub 2} (S-CO{sub 2}) cycle has been proposed. Although there are many researches on S-CO{sub 2} cycle concept and turbomachinery, very few research works considered pipe selection criteria for the S-CO{sub 2} cycle. As one of the most important parts of the plant, this paper will discuss how to select a suitable pipe considering thermal expansion for the S-CO{sub 2} power plant and perform a conceptual design of SFR type SMR. The S-CO{sub 2} cycle can improve the safety of SFR as preventing the SWR by changing the working fluid. Additionally, not only the relatively high efficiency with 450-750 .deg. C turbine inlet temperature, but also the physically compact footprint are advantages of the S-CO{sub 2} cycle. However the pipe design is more complicated than existing power plant because it has high pressure and temperature conditions and needs high mass flow rate. By designing the piping system for a small modular -SFR, the compactness and simplicity of the S-CO{sub 2} cycle are re-confirmed. Moreover, in this paper, realistic and safe pipe design was conducted by considering thermal expansion in the high pressure and temperature conditions. Although total pipe pressure drop is somewhat high, the cycle thermal efficiency is still higher than the existing steam Rankine cycle. Additional study for a larger system such as 300MW class system in MIT report will be conducted in the future study. From the preliminary estimation when the S-CO{sub 2} system becomes large, the pipe diameter may exceed the current ASME standard. This means that more innovative approach

Analysis and assessment of environmental impacts of small hydro power plant in Slovakia

Science.gov (United States)

Zeleňáková, M.; Fijko, R.; Remeňáková, I.

2017-10-01

Environmental impact assessment (EIA) is an important process that, prior to approval of the investment plan, can provide a detailed examination of the likely and foreseeable impacts of proposed construction activity on the environment. The objective of this paper is to apply a specific methodology for the analysis and evaluation of the environmental impacts of selected constructions, namely, small hydro power plant, using matrix of impacts. This analysis method is intended not only to increase the clarity and precision of the evaluation process, but also to align it with the requirements of the environmental impact assessment system. This modification should improve the reliability of the environmental impact assessment, and could moreover also be applied to other infrastructure projects. Comparison of alternatives and designation of the optimal variant are implemented based on selected criteria that objectively describe the characteristic lines of the planned alternatives of activity and their impact on the environment. The use of proper EIA procedures can help the decision-makers to formulate proper activities based on qualified decisions. The designed project in Spišské Bystré, Slovakia is used as a case study to clarify and exemplify the methodology and techniques.

Retrofitting the small-scale hydro power plant 'La Chocolatiere' in Echandens-Bussigny, Switzerland

International Nuclear Information System (INIS)

2008-05-01

This report for the Swiss Federal Office of Energy (SFOE) is a project study for the retrofitting of a small-scale hydro power plant installed on the River Venoge, between the communities of Echandens and Bussigny, western Switzerland. At this site, hydro power is used since the 18 th century. A permanent license to use at most 3 m 3 /s is available. The study concludes that the maximum flow rate of 6 m 3 /s would be more advantageous, implying a 35 cm higher dam on the river. Two turbines could then be installed, leading to the maximum electric power of 177 kW and the power production of 727,000 kWh/y. From the detailed inventory of the retrofitting work and the installation of the new turbines - including a new fish ladder according to the legislation in force - the authors conclude that electricity could be generated at a cost amounting to about CHF 0.24/kWh. It is recommended to request the modification of the water use license in order to be able to use up to 6 m 3 /s.

Herbivore-plant interactions: mixed-function oxidases and secondary plant substances.

Science.gov (United States)

Brattsten, L B; Wilkinson, C F; Eisner, T

1977-06-17

The mixed-function oxidases of a polyphagous insect larva (the southern armyworm, Spodoptera eridania) were found to be induced by a diversity of secondary plant substances. The induction proceeds rapidly and in response to a small quantity of secondary substance. Following induction, the larva is less susceptible to dietary poisoning. It is argued that mixed-function oxidases play a major role in protecting herbivores against chemical stress from secondary plant substances.

Safety features in small integral PWR ABV-6

Energy Technology Data Exchange (ETDEWEB)

Baranaev, Youry D. [State Scientific Centre of Russian Federation - Institure for Physics and Power Engineering, Obninsk (Russian Federation)

1996-04-15

Long term operation experience of Bilibin Nuclear Power Plant with four EGP-6 reactors of 48MWth each at Chukotka peninsula, as well as results of manifold feasibility studies showed that Small Reactors (SR) have and will have promising market potential in outlying isolated regions of Russia as viable alternative of fossil fuel energy sources. Detailed design and licensing of the Small Floating Nuclear Power Plant Valamin/1/ with two integral pressurized water reactors ABV-6/2, 3/ is under way in Russia. The basic ABV-6 reactor design performance are presented in Table 1.

Many and small or large and few? A comparison of the environmental effects of different strategies for the development of hydropower plants.; Mange og smaa eller store og faa? En sammenligning av miljoevirkningene ved ulike strategier for utvikling av vannkraft.

Energy Technology Data Exchange (ETDEWEB)

Bakken, Tor Haakon; Sundt, Haakon; Ruud, Audun

2012-11-01

This study compared the cumulative environmental impact of 27 small hydro power plants to the environmental impact of an average of three large hydropower plants, which range from the small farms and the average of the major producing about as much energy. Based on the empirical basis used in this study are the environmental impacts of large hydropower fewer and less severe than the cumulative environmental impacts from the 27 small plants. The results are, however marginal in favor of big hydro power plants and suffers from uncertainties due to lack of precision in the raw data, limitations of the methodic of accumulating environmental effects of many small facilities and extensive use of discretion in the transition between the scientific description of the environmental impacts and impact classes (Statens Vegvesen, 2006). The input data in the study has primarily been published available environmental impact assessment (KU). The results must therefore be said to have limited power statement in order to draw general conclusions. The identified environmental effects are to some extent, different from the type and size, so that an individual valuation and political or administrative priorities will to a large extent determine the preferred strategy for the development of hydropower. From 2012 promoted the production stimulating action as a result of common certificate market with Sweden. Small hydro power plants has so far been a priority in Norway, but when Norway implements EU Water Framework Directive in all areas of precipitation, one should be aware of our findings, especially regarding the potential in expanding of existing hydropower plants. (auth)

Comparative Proteomic Analysis of Susceptible and Resistant Rice Plants during Early Infestation by Small Brown Planthopper

Directory of Open Access Journals (Sweden)

Yan Dong

2017-10-01

Full Text Available The small brown planthopper (Laodelphax striatellus Fallén, Homoptera, Delphacidae-SBPH is one of the major destructive pests of rice (Oryza sativa L.. Understanding on how rice responds to SBPH infestation will contribute to developing strategies for SBPH control. However, the response of rice plant to SBPH is poorly understood. In this study, two contrasting rice genotypes, Pf9279-4 (SBPH-resistant and 02428 (SBPH-susceptible, were used for comparative analysis of protein profiles in the leaf sheath of rice plants in responses to SBPH infestation. One hundred and thirty-two protein spots that were differentially expressed between the resistant and susceptible rice lines were identified with significant intensity differences (≥2-fold, P < 0.05 at 0, 6, and 12 h after SBPH infestation. Protein expression profile analysis in the leaf sheath of SBPH-resistant and SBPH-susceptible rice lines after SBPH infestation showed that proteins induced by SBPH feeding were involved mainly in stress response, photosynthesis, protein metabolic process, carbohydrate metabolic process, energy metabolism, cell wall-related proteins, amino acid metabolism and transcriptional regulation. Gene expression analysis of 24 differentially expressed proteins (DEPs showed that more than 50% DEPs were positively correlated with their mRNA levels. Analysis of some physiological indexes mainly involved in the removal of oxygen reactive species showed that the levels of superoxide dismutase (SOD and glutathione (GSH were considerably higher in Pf9279-4 than 02428 during SBPH infestation. The catalase (CAT activity and hydroxyl radical inhibition were lower in Pf9279-4 than 02428. Analysis of enzyme activities indicates that Pf9279-4 rice plants defend against SBPH through the activation of the pathway of the salicylic acid (SA-dependent systemic acquired resistance. In conclusion, this study provides some insights into the molecular networks involved on cellular and

Small seed size increases the potential for dispersal of wetland plants by ducks

NARCIS (Netherlands)

Soons, M.B.; van der Vlugt, C.; van Lith, B.; Heil, G.W.; Klaassen, M.R.J.

2008-01-01

1. Long-distance dispersal (LDD) is important in plants of dynamic and ephemeral habitats. For plants of dynamic wetland habitats, waterfowl are generally considered to be important LDD vectors. However, in comparison to the internal (endozoochorous) dispersal of terrestrial plants by birds,

Role of the Rubisco Small Subunit

Energy Technology Data Exchange (ETDEWEB)

Spreitzer, Robert Joseph [Univ. of Nebraska, Lincoln, NE (United States)

2016-11-05

Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) catalyzes the rate-limiting step of CO₂ fixation in photosynthesis. However, it is a slow enzyme, and O₂ competes with CO₂ at the active site. Oxygenation initiates the photorespiratory pathway, which also results in the loss of CO₂. If carboxylation could be increased or oxygenation decreased, an increase in net CO₂ fixation would be realized. Because Rubisco provides the primary means by which carbon enters all life on earth, there is much interest in engineering Rubisco to increase the production of food and renewable energy. Rubisco is located in the chloroplasts of plants, and it is comprised of two subunits. Much is known about the chloroplast-gene-encoded large subunit (rbcL gene), which contains the active site, but much less is known about the role of the nuclear-gene-encoded small subunit in Rubisco function (rbcS gene). Both subunits are coded by multiple genes in plants, which makes genetic engineering difficult. In the eukaryotic, green alga Chlamydomonas reinhardtii, it has been possible to eliminate all the Rubisco genes. These Rubisco-less mutants can be maintained by providing acetate as an alternative carbon source. In this project, focus has been placed on determining whether the small subunit might be a better genetic-engineering target for improving Rubisco. Analysis of a variable-loop structure (βA-βB loop) of the small subunit by genetic selection, directed mutagenesis, and construction of chimeras has shown that the small subunit can influence CO₂/O₂ specificity. X-ray crystal structures of engineered chimeric-loop enzymes have indicated that additional residues and regions of the small subunit may also contribute to Rubisco function. Structural dynamics of the small-subunit carboxyl terminus was also investigated. Alanine-scanning mutagenesis of the most-conserved small-subunit residues has identified a

Techno-economic evaluation of commercial cogeneration plants for small and medium size companies in the Italian industrial and service sector

International Nuclear Information System (INIS)

Armanasco, Fabio; Colombo, Luigi Pietro Maria; Lucchini, Andrea; Rossetti, Andrea

2012-01-01

The liberalization of the electricity market and the concern for energy efficiency have resulted in a surge of interest in cogeneration and distributed power generation. In this regard, companies are encouraged to evaluate the opportunity to build their own cogeneration plant. In Italy, the majority of such companies belong to the industrial or service sector; it is small or medium in size and the electric power ranges between 1 ÷ 10 MW. Commercially available gas turbines are the less expensive option for cogeneration. Particular attention has been given to the possibility of combining an organic Rankine cycle (ORC) with gas turbine, to improve the conversion efficiency. Companies have to account for both technical and economical aspects to assess viability of cogeneration. A techno-economic analysis was performed to identify, in the Italian energy market, which users can take advantage of a cogeneration plant aimed to cover at least part of their energy demand. Since electricity and thermal needs change considerably in the same sector, single product categories have been considered in the analysis. Our work shows that in the industrial sector, independent of the product category, cogeneration is a viable option form a techno-economic perspective. - Highlights: ► The best technologies for 1 ÷ 10 MW distributed generation plant are gas turbine and ORC. ► A variety of commercial cogeneration plants is available to meet user needs. ► Cogeneration is a technical and economical advantage for industrial sector companies.

Development and Deployment Strategy for a Small Advanced Light Water Reactor

International Nuclear Information System (INIS)

Modro, S. Michael; Reith, Raymond; Babka, Pierre

2002-01-01

This paper discusses development and deployment strategies for the modular Multi-Application Small Light Water Reactor (MASLWR). Modularity, small size, capability to transport whole modules including containment on road or by rail, simplicity and safety of this reactor allows innovative deployment strategies for a variety of applications. A larger plant may be constructed of many independent power generation units. The multi-module plant is intended to be operated as a base-load plant. Each reactor is to be operated at full load. However, in response to changes in power demand individual units can brought on line or shut down. A larger plant can be built in small increments to match the power demand balancing capital commitments with revenues from sales of electricity. Also, an unplanned shutdown of a reactor only affects a relatively small portion of the total plant capacity. Simplification of MASLWR design and extensive use of modularization coupled with factory fabrication will result in improved productivity of fieldwork and improved quality achieved in a factory environment. The initial MASLWR design concept development has been completed under the U.S. DOE (Department of Energy) Nuclear Energy Research Initiative (NERI) project. This paper discusses a strategy for developing and deploying a MASLWR plant by 2015. This schedule is realistic because the plant design relies on existing industrial experience and manufacturing capabilities. The development strategy consists of the following elements: concept confirmation through testing (under the NERI program a scaled integral test facility has been constructed and initial testing performed), design concept optimization, and design certification based on prototype testing. (authors)

An overview on small hydro in Brazil

International Nuclear Information System (INIS)

Filho, G.T.

2008-01-01

An overview of small-scale hydro development in Brazil was presented in the context of the Brazilian energy sector. Brazil's energy sector is currently comprised of 45 per cent renewable energy. Brazil is the tenth largest energy producer in the world, with an installed capacity of 105.986 MW. Brazil currently has an estimated 258.410 MW of hydroelectric power potential. Small hydropower (SHP) plants in Brazil are defined as plants capable of producing up to 30 MW of power, with a reservoir area smaller than 12 km 2 . It is estimated that SHP plants will provide 5 per cent of Brazil's electrical supply by 2030. SHP plants in Brazil typically use Kaplan and Pelton hydraulic turbines, as well as Michell-Banki cross-flow turbines. Hydrokinetic turbine prototypes are also being designed at the Federal University of Brazil. Researchers are currently developing a diffuser enhancement design. However, there are currently no designs available that use peripheric generators. Researchers are currently investigating the design of fish-friendly turbines as well as mobile dams. Development projects in the Amazon region were outlined. tabs., figs.

Conserved Responses in a War of Small Molecules between a Plant-Pathogenic Bacterium and Fungi.

Science.gov (United States)

Spraker, Joseph E; Wiemann, Philipp; Baccile, Joshua A; Venkatesh, Nandhitha; Schumacher, Julia; Schroeder, Frank C; Sanchez, Laura M; Keller, Nancy P

2018-05-22

Small-molecule signaling is one major mode of communication within the polymicrobial consortium of soil and rhizosphere. While microbial secondary metabolite (SM) production and responses of individual species have been studied extensively, little is known about potentially conserved roles of SM signals in multilayered symbiotic or antagonistic relationships. Here, we characterize the SM-mediated interaction between the plant-pathogenic bacterium Ralstonia solanacearum and the two plant-pathogenic fungi Fusarium fujikuroi and Botrytis cinerea We show that cellular differentiation and SM biosynthesis in F. fujikuroi are induced by the bacterially produced lipopeptide ralsolamycin (synonym ralstonin A). In particular, fungal bikaverin production is induced and preferentially accumulates in fungal survival spores (chlamydospores) only when exposed to supernatants of ralsolamycin-producing strains of R. solanacearum Although inactivation of bikaverin biosynthesis moderately increases chlamydospore invasion by R. solanacearum , we show that other metabolites such as beauvericin are also induced by ralsolamycin and contribute to suppression of R. solanacearum growth in vitro Based on our findings that bikaverin antagonizes R. solanacearum and that ralsolamycin induces bikaverin biosynthesis in F. fujikuroi , we asked whether other bikaverin-producing fungi show similar responses to ralsolamycin. Examining a strain of B. cinerea that horizontally acquired the bikaverin gene cluster from Fusarium , we found that ralsolamycin induced bikaverin biosynthesis in this fungus. Our results suggest that conservation of microbial SM responses across distantly related fungi may arise from horizontal transfer of protective gene clusters that are activated by conserved regulatory cues, e.g., a bacterial lipopeptide, providing consistent fitness advantages in dynamic polymicrobial networks. IMPORTANCE Bacteria and fungi are ubiquitous neighbors in many environments, including

Plant Growth Regulators as Potential Tools in Aquatic Plant Management: Efficacy and Persistence in Small-Scale Tests

Science.gov (United States)

1994-01-01

gratefully acknowledge the support of the Waterways Experi- ment Station and Drs. Howard Westerdahl and Kurt Getsinger as this research was being conducted...E. Westerdahl , eds., Plant Growth Regulator Society of America, San Antonio, TX, 127-45. Anderson, L. W. J., and Dechoretz, N. (1988). "Bensulfuron...Vegetation Management. J. E. Kaufman and H. E. Westerdahl , eds., Plant Growth Regulator Society of America, San Antonio, TX, 155-86. Herbicide Handbook

The emergence of small hydroelectric plants and the urbanization process in the hinterland of São Paulo state (1890-1930

Directory of Open Access Journals (Sweden)

Débora Marques de Almeida Nogueira Mortati

2011-06-01

Full Text Available The period focused in this paper is from 1890 to 1930, when São Paulo state began its industrialization process, the coffee economy was booming and, in that context, it was founded the first hydroelectric power company in the state. This panorama advanced till 1930, when the coffee economy began in crisis, the industry was already established and the construction of hydroelectric plants after 1930 takes on another course: the large dams, closing the cycle of small hydroelectric plants. The electricity generation in Brazil follows the paths of the railroad; and it was drawing newborders between rural and urban, rural and industry. The cities aspect was changing as the “improvements” were availability, many powered by electricity. The nascent industries were also occupying the space between the railroad and energy; what created new districts and centralities. Thispaper analyzes the processes that hydroelectric energy sets off in São Paulo state; and focuses on itsconsequences.

Small, modular, low-cost coal-fired power plants for the international market

Energy Technology Data Exchange (ETDEWEB)

Zauderer, B.; Frain, B.; Borck, B. [Coal Tech Corp., Merion Station, PA (United States); Baldwin, A.L. [Dept. of Energy, Pittsburgh, PA (United States). Pittsburgh Energy Technology Center

1997-12-31

This paper presents recent operating results of Coal Tech`s second generation, air cooled, slagging coal combustor, and its application to power plants in the 1 to 20 MW range. This 20 MMBtu/hour combustor was installed in a new demonstration plant in Philadelphia, PA in 1995. It contains the combustion components of a 1 MWe coal fired power plant, a 17,500 lb/hour steam boiler, coal storage and feed components, and stack gas cleanup components. The plant`s design incorporates improvements resulting from 2,000 hours of testing between 1987 and 1993 on a first generation, commercial scale, air cooled combustor of equal thermal rating. Since operations began in early 1996, a total of 51 days of testing have been successfully completed. Major results include durability of the combustor`s refractory wall, excellent combustion with high ash concentration in the fuel, removal of 95% to 100% of the slag in the combustor, very little ash deposition in the boiler, major reduction of in-plant parasitic power, and simplified power system control through the use of modular designs of sub-systems and computer control. Rapid fuel switching between oil, gas, and coal and turndown of up to a factor of three was accomplished. All these features have been incorporated in advanced coal fired plant designs in the 1 to 20 MWe range. Incremental capital costs are only $100 to $200/kW higher than comparable rated gas or oil fired steam generating systems. Most of its components and subsystems can be factory assembled for very rapid field installation. The low capital, low operating costs, fuel flexibility, and compatibility with very high ash fuels, make this power system very attractive in regions of the world having domestic supplies of these fuels.

Earthquake hazard assessment and small earthquakes

International Nuclear Information System (INIS)

Reiter, L.

1987-01-01

The significance of small earthquakes and their treatment in nuclear power plant seismic hazard assessment is an issue which has received increased attention over the past few years. In probabilistic studies, sensitivity studies showed that the choice of the lower bound magnitude used in hazard calculations can have a larger than expected effect on the calculated hazard. Of particular interest is the fact that some of the difference in seismic hazard calculations between the Lawrence Livermore National Laboratory (LLNL) and Electric Power Research Institute (EPRI) studies can be attributed to this choice. The LLNL study assumed a lower bound magnitude of 3.75 while the EPRI study assumed a lower bound magnitude of 5.0. The magnitudes used were assumed to be body wave magnitudes or their equivalents. In deterministic studies recent ground motion recordings of small to moderate earthquakes at or near nuclear power plants have shown that the high frequencies of design response spectra may be exceeded. These exceedances became important issues in the licensing of the Summer and Perry nuclear power plants. At various times in the past particular concerns have been raised with respect to the hazard and damage potential of small to moderate earthquakes occurring at very shallow depths. In this paper a closer look is taken at these issues. Emphasis is given to the impact of lower bound magnitude on probabilistic hazard calculations and the historical record of damage from small to moderate earthquakes. Limited recommendations are made as to how these issues should be viewed

Wild Plant Species with Extremely Small Populations Require Conservation and Reintroduction in China

Science.gov (United States)

Hai Ren; Qianmei Zhang; Hongfang Lu; Hongxiao Liu; Qinfeng Guo; Jun Wang; Shuguang Jian; Hai’ou Bao

2012-01-01

China is exceptionally rich in biodiversity, with more than 30000 vascular plant species that include many endemic genera, species of ancient origin, and cultivated plants (Yang et al. 2005). Because of rapid economic development, population growth, pollution, and continuing resource exploitation, China’s plant diversity faces severe threats. According to the Chinese...

Potato yield and quality as a function of the plant density

Directory of Open Access Journals (Sweden)

Eero Varis

1975-05-01

Full Text Available The effects of potato plant density on yield quantity and quality were investigated at the Hankkija Plant Breeding Institute from 1971-73, using seed rates of 1600, 3200 and 4800 kg/ha, and seed sizes of 40, 80 and 120 g. The varieties used were Ijsselster and Record. The number of stems per m2 rose with increasing seed rate and with increasing seed size. Stem number increased with seed rate faster for small seed than for large. The response in stem number was greater for Ijsselster than for Record. The number of stems per seed tuber fell as the plant density rose. The number of tubers per m2 altered in the same direction as the number of stems, but less responsively. The reason for this was that the number of tubers per stem decreased with increasing plant density. The tuber yield showed a continual increase with increasing plant density. At the lowest stem densities (less than 20—25 stems/m2 small seed gave better results than other sizes, but at the higher plant densities, the importance of seed size faded away and the yield was dependant on the plant density alone. Net yield (gross yield 2 x seed rate, however, was higher the smaller the seed used, whatever the stem density. Tuber size decreased when plant density increased, the proportion of large tubers diminishing most, especially when small seed was used. The proportion of small tubers altered more for Ijsselster than for Record. Seed size and seed rate did not on average significantly affect the proportion of Class I potatoes, though small seed gave results slightly better than other sizes. The starch content of the yield rose when the seed rate was increased (16.0-16.3 -16.5 % and fell with increasing seed size (16.5 16.2 16.1 %. The maximum variation was 15.8-16.7 %. The specific gravity distribution improved with increasing plant density. Raw discolouration of the tubers did not alter significantly as the plant density rose. Blackening of the tubers decreased with increasing plant

Optimizing the selection of small-town wastewater treatment processes

Science.gov (United States)

Huang, Jianping; Zhang, Siqi

2018-04-01

Municipal wastewater treatment is energy-intensive. This high energy consumption causes high sewage treatment plant operating costs and increases the energy burden. To mitigate the adverse impacts of China’s development, sewage treatment plants should adopt effective energy-saving technologies. Artificial fortified natural water treatment and use of activated sludge and biofilm are all suitable technologies for small-town sewage treatment. This study features an analysis of the characteristics of small and medium-sized township sewage, an overview of current technologies, and a discussion of recent progress in sewage treatment. Based on this, an analysis of existing problems in municipal wastewater treatment is presented, and countermeasures to improve sewage treatment in small and medium-sized towns are proposed.

Hydroelectric power and hydroelectric power plants. V. 1

International Nuclear Information System (INIS)

1991-06-01

Following the oil crises of 1973 and 1979, there was renewed and justifiable interest in small hydroelectric plants. The maximum power of these plants rarely exceeds 10 MW, and their development will surely increase in the coming decades. Hydraulic power is a national renewable resource, unaffected by geopolitical problems, and above all, non polluting. Many countries with their own hydraulic resources in both the industrialized and the developing world have expressed needs for the development of small hydroelectric plants. Hidroenergia 91 Conference is the opportunity to take stock of knowledge gained in the vast field of small hydroelectric plants. The meeting is divided into four subjects: 1 methods for decision aid; 2 environmental impact and accompanying answers; 3 national development policy; 4 world market and international cooperation. This meeting contains 75 papers, 8 papers are in the INIS scope and 72 papers are in the ENERGY DATA BASE scope

Technical and economical studies on the modernization of small-scale hydroelectric power plants: difficulties and proposals; Estudo tecnico-economicos de mordernizacao de PCH`s: Dificuldades e propostas

Energy Technology Data Exchange (ETDEWEB)

Almeida, Antonio Tadeu Lyrio de; Beltrame, Eduardo; Santos, Afonso Henriques Moreira; Souza, Zulcy [Escola Federal de Engenharia de Itajuba, MG (Brazil)

1989-12-31

This work describes and analyses some technical alternatives to be used in re-designing or reforming small-scale hydroelectric power plants. In addition, some criteria are also presented in order to proceed a comparative evaluation based on economic feasibility 7 refs. 5 figs. 1 tab.

Technical and economical studies on the modernization of small-scale hydroelectric power plants: difficulties and proposals; Estudo tecnico-economicos de mordernizacao de PCH`s: Dificuldades e propostas

Energy Technology Data Exchange (ETDEWEB)

Almeida, Antonio Tadeu Lyrio de; Beltrame, Eduardo; Santos, Afonso Henriques Moreira; Souza, Zulcy [Escola Federal de Engenharia de Itajuba, MG (Brazil)

1990-12-31

This work describes and analyses some technical alternatives to be used in re-designing or reforming small-scale hydroelectric power plants. In addition, some criteria are also presented in order to proceed a comparative evaluation based on economic feasibility 7 refs. 5 figs. 1 tab.

Sewage sludge ash (SSA) from large and small incineration plants as a potential source of phosphorus - Polish case study.

Science.gov (United States)

Smol, Marzena; Kulczycka, Joanna; Kowalski, Zygmunt

2016-12-15

The aim of this research is to present the possibility of using the sewage sludge ash (SSA) generated in incineration plants as a secondary source of phosphorus (P). The importance of issues related to P recovery from waste materials results from European Union (UE) legislation, which indicated phosphorus as a critical raw material (CRM). Due to the risks of a shortage of supply and its impact on the economy, which is greater than other raw materials, the proper management of phosphorus resources is required in order to achieve global P security. Based on available databases and literature, an analysis of the potential use of SSA for P-recovery in Poland was conducted. Currently, approx. 43,000 Mg/year of SSA is produced in large and small incineration plants and according to in the Polish National Waste Management Plan 2014 (NWMP) further steady growth is predicted. This indicates a great potential to recycle phosphorus from SSA and to reintroduce it again into the value chain as a component of fertilisers which can be applied directly on fields. The amount of SSA generated in installations, both large and small, varies and this contributes to the fact that new and different P recovery technology solutions must be developed and put into use in the years to come (e.g. mobile/stationary P recovery installations). The creation of a database focused on the collection and sharing of data about the amount of P recovered in EU and Polish installations is identified as a helpful tool in the development of an efficient P management model for Poland. Copyright © 2016 Elsevier Ltd. All rights reserved.

Multigene phylogeny of land plants with special reference to bryophytes and the earliest land plants.

Science.gov (United States)

Nickrent, D L; Parkinson, C L; Palmer, J D; Duff, R J

2000-12-01

A widely held view of land plant relationships places liverworts as the first branch of the land plant tree, whereas some molecular analyses and a cladistic study of morphological characters indicate that hornworts are the earliest land plants. To help resolve this conflict, we used parsimony and likelihood methods to analyze a 6, 095-character data set composed of four genes (chloroplast rbcL and small-subunit rDNA from all three plant genomes) from all major land plant lineages. In all analyses, significant support was obtained for the monophyly of vascular plants, lycophytes, ferns (including PSILOTUM: and EQUISETUM:), seed plants, and angiosperms. Relationships among the three bryophyte lineages were unresolved in parsimony analyses in which all positions were included and weighted equally. However, in parsimony and likelihood analyses in which rbcL third-codon-position transitions were either excluded or downweighted (due to apparent saturation), hornworts were placed as sister to all other land plants, with mosses and liverworts jointly forming the second deepest lineage. Decay analyses and Kishino-Hasegawa tests of the third-position-excluded data set showed significant support for the hornwort-basal topology over several alternative topologies, including the commonly cited liverwort-basal topology. Among the four genes used, mitochondrial small-subunit rDNA showed the lowest homoplasy and alone recovered essentially the same topology as the multigene tree. This molecular phylogeny presents new opportunities to assess paleontological evidence and morphological innovations that occurred during the early evolution of terrestrial plants.

Opportunities of energy supply of farm holdings on the basis of small-scale renewable energy sources

Science.gov (United States)

Efendiev, A. M.; Nikolaev, Yu. E.; Evstaf'ev, D. P.

2016-02-01

One of the major national economic problems of Russia is raising of agricultural production, which will provide strategic security and sustainable supply of the population with provisions. Creation of subsidiary small holdings, farm holdings, and peasant farm holdings will require addressing issues of energy supply. At considerable distance of small farms from centralized energy systems (by fuel, electricity and thermal energy) it is proposed to create a system of local energy networks on the basis of low-powered power plants using renewable energy sources (RES). There is economic unreasonableness of use of imported components of small power plants. Creation of new combined small power plants on renewable energy sources produced by domestic manufacturers is recommended. Schemes of arrangements of small power plants based on renewable energy sources are proposed, variants and characteristics of a basic source are provided—biogas plants developed by the authors. Calculations revealed that heat and power supply of self-contained farms distant from small power plants based on renewable energy sources is 2.5-2.6 times cheaper than from centralized networks. Production of biogas through anaerobic fermentation of organic waste of cattle complexes is considered as the basis. The analysis of biowaste output in various cattle farms is carried out, and the volume of biogas is determined to meet the requirements of these farms in electrical and thermal energy. The objective of the present article is to study the possibility of creating small combined power plants in Russia based on renewable sources of energy for independent consumers.

Regulatory risks in Brazil - obstacle to the development of new small hydropower plants; Riscos regulatorios no Brasil - obstaculo ao desenvolvimento de novas pequenas centrais hidroeletricas

Energy Technology Data Exchange (ETDEWEB)

Prado Junior, Fernando A. Almeida [Sinerconsult Consultoria Treinamento e Participacoes Ltda., Sao Paulo, SP (Brazil)]. E-mail: fernando@sinerconsult.com.br; Alves, Gilberto [Companhia Energetica de Sao Paulo (CESP), SP (Brazil)]. E-mail: gilberto@cesp.com.br; Yamagushi, Hugo R. [ARSESP - Agencia de Regulacao de Saneamento e Energia do Estado de Sao Paulo, Sao Paulo (Brazil)]. E-mail: hyamagushi@sp.gov.br; Braun, Paulo Victor C.B. [EMAE Empresa Metropolitana de Aguas e Energia Eletrica, Sao Paulo, SP (Brazil)]. E-mail: paulo.victor@emae.sp.gov.br

2008-10-15

The paper analyses the risks of legal and regulatory order that affect the activity of exploration of Small Power Hydro plants in Brazil. In the scope of the main administrative phases of these activities, namely, inventory, basic project, attainment of licenses and connection to the electric grid, the main difficulties faced by entrepreneurs are identified and analysed. (author)

A stream-scale model to optimize the water allocation for Small Hydropower Plants and the application to traditional systems

Science.gov (United States)

Razurel, Pierre; Niayifar, Amin; Perona, Paolo

2017-04-01

Hydropower plays an important role in supplying worldwide energy demand where it contributes to approximately 16% of global electricity production. Although hydropower, as an emission-free renewable energy, is a reliable source of energy to mitigate climate change, its development will increase river exploitation. The environmental impacts associated with both small hydropower plants (SHP) and traditional dammed systems have been found to the consequence of changing natural flow regime with other release policies, e.g. the minimal flow. Nowadays, in some countries, proportional allocation rules are also applied aiming to mimic the natural flow variability. For example, these dynamic rules are part of the environmental guidance in the United Kingdom and constitute an improvement in comparison to static rules. In a context in which the full hydropower potential might be reached in a close future, a solution to optimize the water allocation seems essential. In this work, we present a model that enables to simulate a wide range of water allocation rules (static and dynamic) for a specific hydropower plant and to evaluate their associated economic and ecological benefits. It is developed in the form of a graphical user interface (GUI) where, depending on the specific type of hydropower plant (i.e., SHP or traditional dammed system), the user is able to specify the different characteristics (e.g., hydrological data and turbine characteristics) of the studied system. As an alternative to commonly used policies, a new class of dynamic allocation functions (non-proportional repartition rules) is introduced (e.g., Razurel et al., 2016). The efficiency plot resulting from the simulations shows the environmental indicator and the energy produced for each allocation policies. The optimal water distribution rules can be identified on the Pareto's frontier, which is obtained by stochastic optimization in the case of storage systems (e.g., Niayifar and Perona, submitted) and by

Matching economical, energetic and environmental benefits: An analysis for hybrid CHCP-heat pump systems

International Nuclear Information System (INIS)

Cardona, Ennio; Piacentino, Antonio; Cardona, Fabio

2006-01-01

The optimization of design and operation of combined heat, cooling and power systems usually leads to select different plant lay-outs and size of components, depending on the adopted optimization criterion (maximum profit or energy saving or minimum environmental impact). This occurs when the current energy prices and the normative provisions supporting cogeneration are not able to coincide with the specific customer's interest and the overall 'social interest' for a reduction in energy consumption and in pollutants' emissions. At EU level, polygeneration is considered to have a large potential for residential and commercial buildings district network, for the tertiary sector and for industrial applications. In such applications, it is often convenient to integrate the trigeneration system with a reversible heat pump, because of a low ratio between electric demand and that for heating and cooling. In this paper, the design and operation of such hybrid systems is discussed. The results achievable through different operation modes are compared and, with reference to a 600-rooms hotel and a 300-beds hospital in Italy, the effects on plant design from an hour-by-hour optimization of plant operation are assessed. Finally, the need for a flexible support system for cogeneration plants is put into evidence and some criteria are listed for an effective regulation

Improving the ecohydrological and economic efficiency of Small Hydropower Plants with water diversion

Science.gov (United States)

Razurel, Pierre; Gorla, Lorenzo; Tron, Stefania; Niayifar, Amin; Crouzy, Benoît; Perona, Paolo

2018-03-01

Water exploitation for energy production from Small Hydropower Plant (SHP) is increasing despite human pressure on freshwater already being very intense in several countries. Preserving natural rivers thus requires deeper understanding of the global (i.e., ecological and economic) efficiency of flow-diversion practice. In this work, we show that the global efficiency of SHP river intakes can be improved by non-proportional flow-redistribution policies. This innovative dynamic water allocation defines the fraction of water released to the river as a nonlinear function of river runoff. Three swiss SHP case studies are considered to systematically test the global performance of such policies, under both present and future hydroclimatic regimes. The environmental efficiency is plotted versus the economic efficiency showing that efficient solutions align along a (Pareto) frontier, which is entirely formed by non-proportional policies. On the contrary, other commonly used distribution policies generally lie below the Pareto frontier. This confirms the existence of better policies based on non-proportional redistribution, which should be considered in relation to implementation and operational costs. Our results recommend abandoning static (e.g., constant-minimal-flow) policies in favour of non-proportional dynamic ones towards a more sustainable use of the water resource, also considering changing hydroclimatic scenarios.

Water ferns Azolla spp. (Azollaceae as new host plants for the small China-mark moth, Cataclysta lemnata (Linnaeus, 1758 (Lepidoptera, Crambidae, Acentropinae

Directory of Open Access Journals (Sweden)

Atousa Farahpour-Haghani

2017-01-01

Full Text Available Water ferns (Azolla spp., Azollaceae are reported for the first time as host plants for the larvae of the small China-mark moth Cataclysta lemnata (Linnaeus (Lepidoptera: Crambidae: Acentropinae in rice fields and waterways of northern Iran. Cataclysta lemnata is a semi-aquatic species that has been recorded to feed on Lemnaceae and a few other aquatic plants. However, it has not been reported before on Azolla spp. Larvae use water fern as food source and shelter and, at high population density in the laboratory, they completely wiped water fern from the water surface. Feeding was confirmed after rearing more than eight continual generations of C. lemnata on water fern in the laboratory. Adults obtained this way are darker and have darker fuscous markings in both sexes compared with specimens previously reported and the pattern remains unchanged after several generations.

Model for 3D-visualization of streams and techno-economic estimate of locations for construction of small hydropower plants

International Nuclear Information System (INIS)

Izeiroski, Subija

2012-01-01

The main researches of this dissertation are focused to a development of a model for preliminary assesment of the hydro power potentials for small hydropower plants construction using Geographic Information System - GIS. For this purpose, in the first part of dissertation is developed a contemporary methodological approach for 3D- visualization of the land surface and river streams in a GIS platform. In the methodology approach, as input graphical data are used digitized maps in scale 1:25000, where each map covers an area of 10x14 km and consists of many layers with graphic data in shape (vector) format. Using GIS tools, from the input point and isohyetal contour data layers with different interpolation techniques have been obtained digital elevation model - DEM, which further is used for determination of additional graphic maps with useful land surface parameters such as: slope raster maps, hill shade models of the surface, different maps with hydrologic parameters and many others. The main focus of researches is directed toward the developing of contemporary methodological approaches based on GIS systems, for assessment of the hydropower potentials and selection of suitable location for small hydropower plant construction - SHPs, and especially in the mountainous hilly area that are rich with water resources. For this purpose it is done a practical analysis at a study area which encompasses the watershed area of the Brajchanska River at the east part of Prespa Lake. The main accent considering the analysis of suitable locations for SHP construction is set to the techno-engineering criteria, and in this context is made a topographic analysis regarding the slope (gradient) either of all as well of particular river streams. It is also made a hydrological analysis regarding the flow rates (discharges). The slope analysis is executed at a pixel (cell) level a swell as at a segment (line) level along a given stream. The slope value at segment level gives in GIS

Small break loss of coolant accident analysis of advanced PWR plant designs utilizing DVI line venturis

International Nuclear Information System (INIS)

Kemper, Robert M.; Gagnon, Andre F.; McNamee, Kevin; Cheung, Augustine C.

1995-01-01

The Westinghouse Advanced Passive and evolutionary Pressurizer Water Reactors (i.e. AP600 and APWR) incorporate direct vessel injection (DVI) of emergency core coolant as a means of minimizing the potential spilling of emergency core cooling water during a loss of coolant accident (LOCA). As a result, the most limiting small break LOCA (SBLOCA) event for these designs, with respect core inventory makeup capability, is a postulated double ended rupture of one of the DVI lines. This paper presents the results of a design optimization study that examines the installation of a venturi in the DVI line as a means of limiting the reactor coolant lost from the reactor vessel. The comparison results demonstrate that by incorporating a properly sized venturi in the DVI line, core uncovery concerns as a result of a DVI line break can be eliminated for both the AP600 and APWR plants. (author)

Small Modular Reactors (468th Brookhaven Lecture)

International Nuclear Information System (INIS)

Bari, Robert

2011-01-01

With good reason, much more media attention has focused on nuclear power plants than solar farms, wind farms, or hydroelectric plants during the past month and a half. But as nations around the world demand more energy to power everything from cell phone batteries to drinking water pumps to foundries, nuclear plants are the only non-greenhouse-gas producing option that can be built to operate almost anywhere, and can continue to generate power during droughts, after the sun sets, and when winds die down. To supply this demand for power, designers around the world are competing to develop more affordable nuclear reactors of the future: small modular reactors. Brookhaven Lab is working with DOE to ensure that these reactors are designed to be safe for workers, members of surrounding communities, and the environment and to ensure that the radioactive materials and technology will only be used for peaceful purposes, not weapons. In his talk, Bari will discuss the advantages and challenges of small modular reactors and what drives both international and domestic interest in them. He will also explain how Brookhaven Lab and DOE are working to address the challenges and provide a framework for small modular reactors to be commercialized.

An overview on small hydro in Brazil

Energy Technology Data Exchange (ETDEWEB)

Filho, G.T. [Federal Univ. of Itajuba (Brazil). National Reference Centre for Small Hydro

2008-07-01

An overview of small-scale hydro development in Brazil was presented in the context of the Brazilian energy sector. Brazil's energy sector is currently comprised of 45 per cent renewable energy. Brazil is the tenth largest energy producer in the world, with an installed capacity of 105.986 MW. Brazil currently has an estimated 258.410 MW of hydroelectric power potential. Small hydropower (SHP) plants in Brazil are defined as plants capable of producing up to 30 MW of power, with a reservoir area smaller than 12 km{sup 2}. It is estimated that SHP plants will provide 5 per cent of Brazil's electrical supply by 2030. SHP plants in Brazil typically use Kaplan and Pelton hydraulic turbines, as well as Michell-Banki cross-flow turbines. Hydrokinetic turbine prototypes are also being designed at the Federal University of Brazil. Researchers are currently developing a diffuser enhancement design. However, there are currently no designs available that use peripheric generators. Researchers are currently investigating the design of fish-friendly turbines as well as mobile dams. Development projects in the Amazon region were outlined. tabs., figs.

PlantNATsDB: a comprehensive database of plant natural antisense transcripts.

Science.gov (United States)

Chen, Dijun; Yuan, Chunhui; Zhang, Jian; Zhang, Zhao; Bai, Lin; Meng, Yijun; Chen, Ling-Ling; Chen, Ming

2012-01-01

Natural antisense transcripts (NATs), as one type of regulatory RNAs, occur prevalently in plant genomes and play significant roles in physiological and pathological processes. Although their important biological functions have been reported widely, a comprehensive database is lacking up to now. Consequently, we constructed a plant NAT database (PlantNATsDB) involving approximately 2 million NAT pairs in 69 plant species. GO annotation and high-throughput small RNA sequencing data currently available were integrated to investigate the biological function of NATs. PlantNATsDB provides various user-friendly web interfaces to facilitate the presentation of NATs and an integrated, graphical network browser to display the complex networks formed by different NATs. Moreover, a 'Gene Set Analysis' module based on GO annotation was designed to dig out the statistical significantly overrepresented GO categories from the specific NAT network. PlantNATsDB is currently the most comprehensive resource of NATs in the plant kingdom, which can serve as a reference database to investigate the regulatory function of NATs. The PlantNATsDB is freely available at http://bis.zju.edu.cn/pnatdb/.

Small nuclear reactors for desalination

International Nuclear Information System (INIS)

Goldsmith, K.

1978-01-01

Small nuclear reactors are considered to have an output of not more than 400MW thermal. Since they can produce steam at much higher conditions than needed by the brine heater of a multi-flash desalination unit, it may be economically advantageous to use small reactors for a dual-purpose installation of appropriate size, producing both electricity and desalted water, rather than for a single-purpose desalination plant only. Different combinations of dual-purpose arrangements are possible depending principally on the ratio of electricity to water output required. The costs of the installation as well as of the products are critically dependent on this ratio. For minimum investment costs, the components of the dual-purpose installation should be of a standardised design based on normal commercial power plant practice. This then imposes some restrictions on the plant arrangement but, on the other hand, it facilitates selection of the components. Depending on the electricity to water ratio to be achieved, the conventional part of the installation - essentially the turbines - will form a combination of back-pressure and condensing machines. Each ratio will probably lead to an optimum combination. In the economic evaluation of this arrangement, a distinction must be made between single-purpose and dual-purpose installations. The relationship between output and unit costs of electricity and water will be different for the two cases, but the relation can be expressed in general terms to provide guidelines for selecting the best dimensions for the plant. (author)

Analysis of synchronous and induction generators used at hydroelectric power plant

Science.gov (United States)

Diniş, C. M.; Popa, G. N.; lagăr, A.

2017-01-01

In this paper is presented an analysis of the operating electric generators (synchronous and induction) within a small capacity hydroelectric power plant. Such is treated the problem of monitoring and control hydropower plant using SCADA systems. Have been carried an experimental measurements in small hydropower plant for different levels of water in the lake and various settings of the operating parameters.

Hybrid fuel cells technologies for electrical microgrids

Energy Technology Data Exchange (ETDEWEB)

San Martin, Jose Ignacio; Zamora, Inmaculada; San Martin, Jose Javier; Aperribay, Victor; Eguia, Pablo [Department of Electrical Engineering, University of the Basque Country, Alda. de Urquijo, s/n, 48013 Bilbao (Spain)

2010-09-15

Hybrid systems are characterized by containing two or more electrical generation technologies, in order to optimize the global efficiency of the processes involved. These systems can present different operating modes. Besides, they take into account aspects that not only concern the electrical and thermal efficiencies, but also the reduction of pollutant emissions. There is a wide range of possible configurations to form hybrid systems, including hydrogen, renewable energies, gas cycles, vapour cycles or both. Nowadays, these technologies are mainly used for energy production in electrical microgrids. Some examples of these technologies are: hybridization processes of fuel cells with wind turbines and photovoltaic plants, cogeneration and trigeneration processes that can be configured with fuel cell technologies, etc. This paper reviews and analyses the main characteristics of electrical microgrids and the systems based on fuel cells for polygeneration and hybridization processes. (author)

Overview of the one-day meeting on Small Power Reactors

International Nuclear Information System (INIS)

Rogers, J.M.; Butland, A.T.D.

1991-01-01

The purpose of the meeting was to provide an opportunity for various vendors of small power reactors (under 1MW) to present their ideas and designs, and to subsequently respond to comments and criticisms from an informed audience. Two contrasting papers were presented on the economics of small plant. The perceived view within Nuclear Electric of the economic targets for small PWR reactor designs within the United Kingdom was outlined. The designs under consideration are AP600 and SIR. The presentation concentrated on the various factors making up the overall generating cost, in particular the capital charges, stressing the need to account for the design and launch costs and additional risk of the first-of-a-kind plant. The main conclusion was that small plant were likely to be less economic than large, although utilities may be attracted by this option as a method of restarting a nuclear programme, and that the UK targets would be around Pound 1100/kW installed and 3-3.5 p/kW h. The SIR plant was then used to show how these goals could be achievable, taking series-order factors into account, even if the overnight installed cost for a single plant is more expensive compared with a large plant. In another paper the application of passive safety features within designs was considered given the present UK safety licensing framework regarding diversity, redundancy, the single failure criterion, and past precedent. Aspects suggested to require special attention were deliberate depressurization of the primary circuit, secureness of hot shutdown, and the adequacy of natural circulation for containment cooling. The rest of the papers dealt with various aspects of the AP600 and SIR designs. (author)

A Model of Small Capacity Power Plant in Tateli Village, North Sulawesi

Science.gov (United States)

Sangari, F. J.; Rompas, P. T. D.

2017-03-01

The electricity supply in North Sulawesi is still very limited so ubiquitous electric current outage. It makes rural communities have problems in life because most uses electrical energy. One of the solutions is a model of power plants to supply electricity in Tateli village, Minahasa, North Sulawesi, Indonesia. The objective of this research is to get the model that generate electrical energy for household needs through power plant that using a model of Picohydro with cross flow turbine in Tateli village. The method used the study of literature, survey the construction site of the power plant and the characteristics of the location being a place of research, analysis of hydropower ability and analyzing costs of power plant. The result showed that the design model of cross flow turbines used in pico-hydro hydropower installations is connected to a generator to produce electrical energy maximum of 3.29 kW for household needs. This analyze will be propose to local government of Minahasa, North Sulawesi, Indonesia to be followed.

Small hydro: Policy and potential in Spain

International Nuclear Information System (INIS)

Gutierrez, C.

2001-01-01

In Spain, the benefits of small-scale (less than 10 MW) hydro are apparently rarely appreciated and there is little support from European institutions. The article suggests that small hydro technology can make a significant contribution to the country's energy requirements and create employment, provided certain obstacles can be removed. Data on the number of small hydros in Spain, and of recent installations are given; the share of hydro in Spain's total energy production is 2.5%. The low environmental impact of hydro is extolled, and the conclusions of a recent study of 'environmental impacts of the production of electricity' are listed. There are said to be unreasonable administrative obstacles; for example, it is more difficult to obtain permission to refurbish a 100 kW hydro plant in Castilla y Leon than it is to install a 30,000 kW gas plant. Some details relating to the affect of hydro on aquatic ecosystems, noise levels, and water quality, are given

Efficiency assessment and benchmarking of thermal power plants in India

International Nuclear Information System (INIS)

Shrivastava, Naveen; Sharma, Seema; Chauhan, Kavita

2012-01-01

Per capita consumption of electricity in India is many folds lesser than Canada, USA, Australia, Japan, Chaina and world average. Even though, total energy shortage and peaking shortage were recorded as 11.2% and 11.85%, respectively, in 2008–09 reflecting non-availability of sufficient supply of electricity. Performance improvement of very small amount can lead to large contribution in financial terms, which can be utilized for capacity addition to reduce demand supply gap. Coal fired thermal power plants are main sources of electricity in India. In this paper, relative technical efficiency of 60 coal fired power plants has been evaluated and compared using CCR and BCC models of data envelopment analysis. Target benchmark of input variables has also been evaluated. Performance comparison includes small versus medium versus large power plants and also state owned versus central owned versus private owned. Result indicates poor performance of few power plants due to over use of input resources. Finding reveals that efficiency of small power plants is lower in comparison to medium and large category and also performance of state owned power plants is comparatively lower than central and privately owned. Study also suggests different measures to improve technical efficiency of the plants. - Highlights: ► This study evaluates relative technical efficiency of 60 coal fired thermal power plants of India. ► Input oriented CCR and BCC models of data envelopment analysis have been used. ► Small, medium and large power plants have been compared. ► Study will help investor while setting up new power projects. ► Power plants of different ownerships have also been compared.

Conifers have a unique small RNA silencing signature

OpenAIRE

Dolgosheina, Elena V.; Morin, Ryan D.; Aksay, Gozde; Sahinalp, S. Cenk; Magrini, Vincent; Mardis, Elaine R.; Mattsson, Jim; Unrau, Peter J.

2008-01-01

Plants produce small RNAs to negatively regulate genes, viral nucleic acids, and repetitive elements at either the transcriptional or post-transcriptional level in a process that is referred to as RNA silencing. While RNA silencing has been extensively studied across the different phyla of the animal kingdom (e.g., mouse, fly, worm), similar studies in the plant kingdom have focused primarily on angiosperms, thus limiting evolutionary studies of RNA silencing in plants. Here we report on an u...

Small Hydropower in the United States

Energy Technology Data Exchange (ETDEWEB)

Hadjerioua, Boualem [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Johnson, Kurt [Telluride Energy, Telluride, CO (United States)

2015-09-01

Small hydropower, defined in this report as hydropower with a generating capacity of up to 10 MW typically built using existing dams, pipelines, and canals has substantial opportunity for growth. Existing small hydropower comprises about 75% of the current US hydropower fleet in terms of number of plants. The economic feasibility of developing new small hydropower projects has substantially improved recently, making small hydropower the type of new hydropower development most likely to occur. In 2013, Congress unanimously approved changes to simplify federal permitting requirements for small hydropower, lowering costs and reducing the amount of time required to receive federal approvals. In 2014, Congress funded a new federal incentive payment program for hydropower, currently worth approximately 1.5 cents/kWh. Federal and state grant and loan programs for small hydropower are becoming available. Pending changes in federal climate policy could benefit all renewable energy sources, including small hydropower. Notwithstanding remaining barriers, development of new small hydropower is expected to accelerate in response to recent policy changes.

Survey of disinfection efficiency of small drinking water treatment ...

African Journals Online (AJOL)

A survey involving 181 water treatment plants across 7 provinces of South Africa: Mpumalanga, Limpopo, North West, Free State, KwaZulu-Natal, Eastern Cape and Western Cape was undertaken to identify the challenges facing small water treatment plants (SWTPs) in South Africa . Information gathered included ...

Towards annotating the plant epigenome: the Arabidopsis thaliana small RNA locus map.

Science.gov (United States)

Hardcastle, Thomas J; Müller, Sebastian Y; Baulcombe, David C

2018-04-20

Based on 98 public and internal small RNA high throughput sequencing libraries, we mapped small RNAs to the genome of the model organism Arabidopsis thaliana and defined loci based on their expression using an empirical Bayesian approach. The resulting loci were subsequently classified based on their genetic and epigenetic context as well as their expression properties. We present the results of this classification, which broadly conforms to previously reported divisions between transcriptional and post-transcriptional gene silencing small RNAs, and to PolIV and PolV dependencies. However, we are able to demonstrate the existence of further subdivisions in the small RNA population of functional significance. Moreover, we present a framework for similar analyses of small RNA populations in all species.

Air pollution impedes plant-to-plant communication, but what is the signal?

Science.gov (United States)

Blande, James D; Li, Tao; Holopainen, Jarmo K

2011-07-01

Since the first reports that undamaged plants gain defensive benefits following exposure to damaged neighbors, the idea that plants may signal to each other has attracted much interest. There has also been substantial debate concerning the ecological significance of the process and the evolutionary drivers. Part of this debate has centered on the distance over which signaling between plants occurs in nature. In a recent study we showed that an ozone concentration of 80 ppb, commonly encountered in nature, significantly reduces the distance over which plant-plant signaling occurs in lima bean. We went on to show that degradation of herbivore-induced plant volatiles by ozone is the likely mechanism for this. The key question remaining from our work was that if ozone is degrading the signal in transit between plants, which chemicals are responsible for transmitting the signal in purer air? Here we present the results of a small scale experiment testing the role of the two most significant herbivore-induced terpenes and discuss our results in terms of other reported functions for these chemicals in plant-plant signaling.

Mutation breedings in ornamental plants

International Nuclear Information System (INIS)

Matsubara, Hisao

1984-01-01

Several methods of obtaining somatic mutant plants by γ-ray irradiation on pieces of tissues as in vitro adventitious bud technique or small cutting methods with repeated pruning are described. 1) The irradiation to the adventitious buds in the small pieces of organ cultured in vitro and to the small cuttings are employed. Culture beds of agar or of Japanese Kanuma soil were used in vitro culture. In these experiments, Japanese Kanuma soil bed in in vitro culture worked well for root development and transplant of the induced mutants. 2) Combination with in vitro culture and repeated pruning technique were used for isolation and fixation of solid somatic mutant from small sectorial mutation induced by irradiation. This method was successful for begonia, chrysanthemum, aberia and winter daphne. 3) These data indicates that most of the induced mutant plants were non-chimeric, while a few others were chimeric. Among the new varieties, ''Gin-Sei'', ''Ryoku-Ha'', ''Big-Cross'', ''Kaede-Iron'', ''Mei-Fu-Hana-Tsukubane-Utsugi'' and ''Daphne-γ-3'' are non-chimeric, and ''Mini-Mini-Iron'' and ''Orange-Iron'' are chimeric. Moreover, these new varieties have remarkably differed in size and in color pattern from original variety. From the experimental results of somatic mutation, it is indicated that plant tissue culture have enormous potential in radiation breeding and in rapid propagation of the somatic mutant. (author)

Habitat, food, and small mammal community structure in Namaqualand

Directory of Open Access Journals (Sweden)

M. van Deventer

2006-12-01

Full Text Available The effect of habitat differences and food availability on small mammal (rodent and elephant shrew species richness, diversity, density and biomass was investigated in Namaqualand, South Africa. Species richness in the three habitats sampled, namely Upland Succulent Karoo, Dry Riverine Shrub and North-western Mountain Renosterveld was low, with only 2–4 species per habitat. Rodents trapped were predominantly Gerbillurus paeba and Aethomys namaquensis, with fewer Mus minutoides and Petromyscus sp. The only non-rodent was the elephant shrew Elephantulus edwardii. Ten habitat features, the percentage of total plant cover, tree cover, shrub cover, grass cover, plant litter, total basal cover, sand, gravel or rock cover, and the dominant plant height were recorded at 30 randomly chosen points on five sampling grids in each habitat. Small mammal density and biomass was significantly correlated with food availability (green foliage cover, seeds, and relative density and biomass of insects. Species richness and diversity of small mammals were significantly correlated with shrub cover. Numbers and biomass of specific species correlated significantly with different habitat features in each case.

Landscape configurational heterogeneity by small-scale agriculture, not crop diversity, maintains pollinators and plant reproduction in western Europe.

Science.gov (United States)

Hass, Annika L; Kormann, Urs G; Tscharntke, Teja; Clough, Yann; Baillod, Aliette Bosem; Sirami, Clélia; Fahrig, Lenore; Martin, Jean-Louis; Baudry, Jacques; Bertrand, Colette; Bosch, Jordi; Brotons, Lluís; Burel, Françoise; Georges, Romain; Giralt, David; Marcos-García, María Á; Ricarte, Antonio; Siriwardena, Gavin; Batáry, Péter

2018-02-14

Agricultural intensification is one of the main causes for the current biodiversity crisis. While reversing habitat loss on agricultural land is challenging, increasing the farmland configurational heterogeneity (higher field border density) and farmland compositional heterogeneity (higher crop diversity) has been proposed to counteract some habitat loss. Here, we tested whether increased farmland configurational and compositional heterogeneity promote wild pollinators and plant reproduction in 229 landscapes located in four major western European agricultural regions. High-field border density consistently increased wild bee abundance and seed set of radish ( Raphanus sativus ), probably through enhanced connectivity. In particular, we demonstrate the importance of crop-crop borders for pollinator movement as an additional experiment showed higher transfer of a pollen analogue along crop-crop borders than across fields or along semi-natural crop borders. By contrast, high crop diversity reduced bee abundance, probably due to an increase of crop types with particularly intensive management. This highlights the importance of crop identity when higher crop diversity is promoted. Our results show that small-scale agricultural systems can boost pollinators and plant reproduction. Agri-environmental policies should therefore aim to halt and reverse the current trend of increasing field sizes and to reduce the amount of crop types with particularly intensive management. © 2018 The Author(s).

Plant Secondary Compounds in Small Ruminant Feeding

DEFF Research Database (Denmark)

Gravador, Rufielyn Sungcaya

to the utilization of cheaper resources as alternatives to reduce the production cost. Here, locally available materials and agro-industrial by-products commonly found in the Mediterranean countries (citrus pulp, carob pulp, and olive cake) were used in feeding trials with lambs and the effects on meat quality were...... evaluated. These plant-derived materials contain considerable amounts of secondary bioactive metabolites, which affect the fatty acid composition and/or act as antioxidants. Hence, it was hypothesized that at appropriate levels of inclusion in to the lamb diets, these feedstuffs would not negatively affect...... animal health and productivity, and would represent a strategy to naturally produce a healthy and oxidatively stable meat. In the first study (Experiment 1), Comisana male lambs were fed for 60 days: a conventional cereal-based concentrate diet, or concentrates in which 24% or 35% dried citrus pulp...

Is there a market for small reactors in America

International Nuclear Information System (INIS)

Behrens, C.E.

1984-01-01

In a study prepared by the U.S. Library of Congress Research Service on the economic potential of smaller sized plants in today's economy, the cost of producing power was modelled for a utility with specified financial and production parameters. Two reference cases were considered: in one, it was assumed that the utility would build 400 MWe nuclear units as necessary to meet its growth in load; in the second, that it would meet its load growth by building 1200 MWe units. The main conclusion was that the economies of scale of large plants tend to be overtaken by financing difficulties which are avoided if small units are built. The results of the cases indicate that small nuclear power plants could have a market among United States utilities. (U.K.)

Invasive plant species in hardwood tree plantations

Science.gov (United States)

Rochelle R. Beasley; Paula M. Pijut

2010-01-01

Invasive plants are species that can grow and spread aggressively, mature quickly, and invade an ecosystem causing economic and environmental damage. Invasive plants usually invade disturbed areas, but can also colonize small areas quickly, and may spread and dominate large areas in a few short years. Invasive plant species displace native or desirable forest...

Airborne multispectral identification of individual cotton plants using consumer-grade cameras

Science.gov (United States)

Although multispectral remote sensing using consumer-grade cameras has successfully identified fields of small cotton plants, improvements to detection sensitivity are needed to identify individual or small clusters of plants. The imaging sensor of consumer-grade cameras are based on a Bayer patter...

Plant Metabolomics: An Indispensable System Biology Tool for Plant Science

Directory of Open Access Journals (Sweden)

Jun Hong

2016-06-01

Full Text Available As genomes of many plant species have been sequenced, demand for functional genomics has dramatically accelerated the improvement of other omics including metabolomics. Despite a large amount of metabolites still remaining to be identified, metabolomics has contributed significantly not only to the understanding of plant physiology and biology from the view of small chemical molecules that reflect the end point of biological activities, but also in past decades to the attempts to improve plant behavior under both normal and stressed conditions. Hereby, we summarize the current knowledge on the genetic and biochemical mechanisms underlying plant growth, development, and stress responses, focusing further on the contributions of metabolomics to practical applications in crop quality improvement and food safety assessment, as well as plant metabolic engineering. We also highlight the current challenges and future perspectives in this inspiring area, with the aim to stimulate further studies leading to better crop improvement of yield and quality.

Plant Metabolomics: An Indispensable System Biology Tool for Plant Science

Science.gov (United States)

Hong, Jun; Yang, Litao; Zhang, Dabing; Shi, Jianxin

2016-01-01

As genomes of many plant species have been sequenced, demand for functional genomics has dramatically accelerated the improvement of other omics including metabolomics. Despite a large amount of metabolites still remaining to be identified, metabolomics has contributed significantly not only to the understanding of plant physiology and biology from the view of small chemical molecules that reflect the end point of biological activities, but also in past decades to the attempts to improve plant behavior under both normal and stressed conditions. Hereby, we summarize the current knowledge on the genetic and biochemical mechanisms underlying plant growth, development, and stress responses, focusing further on the contributions of metabolomics to practical applications in crop quality improvement and food safety assessment, as well as plant metabolic engineering. We also highlight the current challenges and future perspectives in this inspiring area, with the aim to stimulate further studies leading to better crop improvement of yield and quality. PMID:27258266

Role of miRNAs and siRNAs in biotic and abiotic stress responses of plants

KAUST Repository

Khraiwesh, Basel

2012-02-01

Small, non-coding RNAs are a distinct class of regulatory RNAs in plants and animals that control a variety of biological processes. In plants, several classes of small RNAs with specific sizes and dedicated functions have evolved through a series of pathways. The major classes of small RNAs include microRNAs (miRNAs) and small interfering RNAs (siRNAs), which differ in their biogenesis. miRNAs control the expression of cognate target genes by binding to reverse complementary sequences, resulting in cleavage or translational inhibition of the target RNAs. siRNAs have a similar structure, function, and biogenesis as miRNAs but are derived from long double-stranded RNAs and can often direct DNA methylation at target sequences. Besides their roles in growth and development and maintenance of genome integrity, small RNAs are also important components in plant stress responses. One way in which plants respond to environmental stress is by modifying their gene expression through the activity of small RNAs. Thus, understanding how small RNAs regulate gene expression will enable researchers to explore the role of small RNAs in biotic and abiotic stress responses. This review focuses on the regulatory roles of plant small RNAs in the adaptive response to stresses. This article is part of a Special Issue entitled: Plant gene regulation in response to abiotic stress. © 2011 Elsevier B.V.

Application of laser cladding method to small-diameter stainless steel pipes in actual nuclear plant

International Nuclear Information System (INIS)

Atago, Y.; Yamadera, M.; Tsuji, H.; Shiraiwa, T.; Kanno, M.

1995-01-01

Recently, to prevent stress corrosion cracking (SCC) the material of stainless steel (Type 304), a laser cladding method which produces a highly corrosion-resisting coating (cladding) to be formed on the surface of the material was developed. This is applicable to a long distance and narrow space, because of the good accessibility of the YAG (Yttrium-Aluminum Garnet) laser beam that can be transmitted through an optical fiber. In this method, a paste mixed metallic powder and heating resistive organic solvent is firstly placed on the inner surface of a small pipe and then a YAG laser beam transmitted through an optical fiber is irradiated to the paste, which will be melted and formed a clad subsequently, which is excellent in corrosion resistance. Finally, it can be achieved further resistance against the SCC due to the clad layer formed thus on the surface of the material. Recently, this Laser Cladding method was practically and successfully applied to the actual BWR Nuclear Power Plant in Japan. This report introduces the laser cladding technique, the equipments developed for practical application in the field

Evaluation of vibration and vibration fatigue life for small bore pipe in nuclear power plants

International Nuclear Information System (INIS)

Wang Zhaoxi; Xue Fei; Gong Mingxiang; Ti Wenxin; Lin Lei; Liu Peng

2011-01-01

The assessment method of the steady state vibration and vibration fatigue life of the small bore pipe in the supporting system of the nuclear power plants is proposed according to the ASME-OM3 and EDF evaluation methods. The GGR supporting pipe system vibration is evaluated with this method. The evaluation process includes the filtration of inborn sensitivity, visual inspection, vibration tests, allowable vibration effective velocity calculation and vibration stress calculation. With the allowable vibration effective velocity calculated and the vibration velocity calculated according to the acceleration data tested, the filtrations are performed. The vibration stress at the welding coat is calculated with the spectrum method and compared with the allowable value. The response of the stress is calculated with the transient dynamic method, with which the fatigue life is evaluated with the Miners linear accumulation model. The vibration stress calculated with the spectrum method exceeds the allowable value, while the fatigue life calculated from the transient dynamic method is larger than the designed life with a big safety margin. (authors)

The biochemical basis of plant development

NARCIS (Netherlands)

Weijers, D.

2013-01-01

Plants develop highly elaborate structures, ranging from small mosses to large trees. All these structures are made by stem cells and consist of a few basic types of tissue. The field of Biochemistry of Plant Development studies the mechanisms by which regulatory proteins control the formation of

Green-house gas mitigation capacity of a small scale rural biogas plant calculations for Bangladesh through a general life cycle assessment.

Science.gov (United States)

Rahman, Khondokar M; Melville, Lynsey; Fulford, David; Huq, Sm Imamul

2017-10-01

Calculations towards determining the greenhouse gas mitigation capacity of a small-scale biogas plant (3.2 m 3 plant) using cow dung in Bangladesh are presented. A general life cycle assessment was used, evaluating key parameters (biogas, methane, construction materials and feedstock demands) to determine the net environmental impact. The global warming potential saving through the use of biogas as a cooking fuel is reduced from 0.40 kg CO 2 equivalent to 0.064 kg CO 2 equivalent per kilogram of dung. Biomethane used for cooking can contribute towards mitigation of global warming. Prior to utilisation of the global warming potential of methane (from 3.2 m 3 biogas plant), the global warming potential is 13 t of carbon dioxide equivalent. This reduced to 2 t as a result of complete combustion of methane. The global warming potential saving of a bioenergy plant across a 20-year life cycle is 217 t of carbon dioxide equivalent, which is 11 t per year. The global warming potential of the resultant digestate is zero and from construction materials is less than 1% of total global warming potential. When the biogas is used as a fuel for cooking, the global warming potential will reduce by 83% compare with the traditional wood biomass cooking system. The total 80 MJ of energy that can be produced from a 3.2 m 3 anaerobic digestion plant would replace 1.9 t of fuel wood or 632 kg of kerosene currently used annually in Bangladesh. The digestate can also be used as a nutrient rich fertiliser substituting more costly inorganic fertilisers, with no global warming potential impact.

Hydraulics and gas exchange recover more rapidly from severe drought stress in small pot-grown grapevines than in field-grown plants.

Science.gov (United States)

Romero, Pascual; Botía, Pablo; Keller, Markus

2017-09-01

quickly following restoration of Ψ s , although gas exchange recovery did not directly depend on recovery of K canopy . In field-grown vines, recovery of water status, gas exchange and hydraulic functionality was slower than in pot-grown plants, and low g s after rewatering was related to sustained decreased K plant , K canopy and K shoot and lower water transport to leaves. These results suggest that caution should be exercised when scaling up conclusions from experiments with small pot-grown plants to field conditions. Copyright © 2017 Elsevier GmbH. All rights reserved.

Posture manipulation for rescue activity via small traction robots

International Nuclear Information System (INIS)

Iwano, Yuki; Osuka, Koichi; Amano, Hisanori

2006-01-01

We discuss a conceptual design of rescue robots against nuclear-power plant accidents. We claim that the rescue robots in nuclear-power plants should have the following properties. (1) The size is small. (2) The structure is simple. (3) The number of the robots is large. This paper studies the rescue robots to rescue people in an area polluted with radioactive leakage in nuclear power institutions. In particular, we propose a rescue system which consists of a group of small mobile robots. First, small traction robots set the posture of the fainted victims to carry easily, and carry them to the safety space with the mobile robots for the stretcher composition. In this paper, we describe the produced small traction robots. And, we confirm that the robots can manipulate a 40 kg dummy doll's posture. We also examine the optimal number of robots from a perspective of working efficiency in the assumption spot. (author)

Induced mutations - a tool in plant research

International Nuclear Information System (INIS)

1981-01-01

These proceedings include 34 papers and 18 brief descriptions of poster presentations in the following areas as they are affected by induced mutations: advancement of genetics, plant evolution, plant physiology, plant parasites, plant symbioses, in vitro culture, gene ecology and plant breeding. Only a relatively small number of papers are of direct nuclear interest essentially in view of the mutations being induced by ionizing radiations. The papers of nuclear interest have been entered as separate and individual items of input

Business Opportunities for Small Reactors

International Nuclear Information System (INIS)

Minato, Akio; Nishimura, Satoshi; Brown, Neil W.

2007-01-01

This report assesses the market potential and identifies a number of potential paths for developing the small nuclear reactor business. There are several potential opportunities identified and evaluated. Selecting a specific approach for the business development requires additional information related to a specific market and sources of capital to support the investment. If and how a market for small nuclear plants may develop is difficult to predict because of the complexity of the economic and institutional factors that will influence such development. Key factors are; economics, safety, proliferation resistance and investment risk. The economic and political interest of any of the identified markets is also dependent on successful demonstration of the safety and reliability of small nuclear reactor. Obtaining a US-NRC Standard Design approval would be an important development step toward establishing a market for small reactors. (authors)

The 'Les iles' small-hydro power plant - Summary analysis; Analyse sommaire. Petite centrale hydroelectrique de Sombeval 'Les iles' - Rapport 2008

Energy Technology Data Exchange (ETDEWEB)

Hausmann, M.

2008-01-15

This report for the Swiss Federal Office of Energy (SFOE) takes a look at a project for the realisation of a small hydro-power plant on the River Suze in the Swiss Jura Mountains. The installation is to be made at the site of a small dam that previously provided water for a water-wheel-driven sawmill. A fish-pass at the site is also foreseen. The report presents details on the hydrological data for the river and the dimensioning of the installation. The hydrological installations and the turbine foreseen are described and discussed, as are the regulation of water levels and the removal of river sediment. The electricity production expected is discussed, as is the economic viability of the project.

Small scale combined woodgas power plant

International Nuclear Information System (INIS)

Gulbis, V.

2003-01-01

As a first attempt to introduce biomass gasification technology in Latvia at the Faculty of Engineering of Latvia University of Agriculture an integral small scale combined heat and power (CHP) system based on a used Russian-made diesel-alternator set with electrical output 100 kWe was developed. The diesel is converted to dual fuel gas engine, using producer gas as the main fuel and gas oil as pilot fuel. To get sufficiently clean (tar content ≤ 250 mg/m 3 ) woodgas for using in IC engine a downdraft type of gasifier was chosen designed and constructed on the IMBERT gasifier principles. The test runs of the first experimental model showed that the engine does not develop expected power because of high resistance of gasifier and gas cleaning system does not work sufficiently enough. There was rather high level of tar content in woodgas because the temperature in the reduction zone was low. Calculations were carried out and new technological scheme of gasification system was worked out, introducing innovative ideas aimed on improving the working parameters (author)

Differential responses of soil bacteria, fungi, archaea and protists to plant species richness and plant functional group identity.

Science.gov (United States)

Dassen, Sigrid; Cortois, Roeland; Martens, Henk; de Hollander, Mattias; Kowalchuk, George A; van der Putten, Wim H; De Deyn, Gerlinde B

2017-08-01

Plants are known to influence belowground microbial community structure along their roots, but the impacts of plant species richness and plant functional group (FG) identity on microbial communities in the bulk soil are still not well understood. Here, we used 454-pyrosequencing to analyse the soil microbial community composition in a long-term biodiversity experiment at Jena, Germany. We examined responses of bacteria, fungi, archaea, and protists to plant species richness (communities varying from 1 to 60 sown species) and plant FG identity (grasses, legumes, small herbs, tall herbs) in bulk soil. We hypothesized that plant species richness and FG identity would alter microbial community composition and have a positive impact on microbial species richness. Plant species richness had a marginal positive effect on the richness of fungi, but we observed no such effect on bacteria, archaea and protists. Plant species richness also did not have a large impact on microbial community composition. Rather, abiotic soil properties partially explained the community composition of bacteria, fungi, arbuscular mycorrhizal fungi (AMF), archaea and protists. Plant FG richness did not impact microbial community composition; however, plant FG identity was more effective. Bacterial richness was highest in legume plots and lowest in small herb plots, and AMF and archaeal community composition in legume plant communities was distinct from that in communities composed of other plant FGs. We conclude that soil microbial community composition in bulk soil is influenced more by changes in plant FG composition and abiotic soil properties, than by changes in plant species richness per se. © 2017 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

Tailorable Release of Small Molecules Utilizing Plant Viral Nanoparticles and Fibrous Matrix

Science.gov (United States)

Cao, Jing

We have engineered Red clover necrotic mosaic virus (RCNMV) derived plant viral nanoparticles (PVNs) within a fibrous matrix to optimize its application for delivery and controlled release of active ingredients. RCNMV's structure and unique response to divalent cation depletion and re-addition enables the infusion of small molecules into its viral capsid through a pore formation mechanism. While this PVN technology shows a potential use in nano-scale therapeutic drug delivery, its inherent molecular dynamics to environmental stimuli places a constraint on its application and functionality as a vehicle for tailorable release of loading cargo. In this study, we enhance the understanding of the PVN technology by elucidating its mechanism for loading and triggered release of doxorubicin (Dox), a chemotherapeutic drug for breast cancer. Of critical importance is the methodology for manipulation of Dox's loading capacity and its binding location on either the exterior or interior of the virion capsid. The ability to control the active ingredient binding location provides an additional approach of tunable release from the PVN delivery vehicle besides its inherent pH- and ion- responsive release of loading cargo. The efficacious and controlled release strategy for agricultural active ingredients, such as nematicides, is also a large social need right now. Crop infestation of plant parasite nematodes causes in excess of 157 billion in worldwide crop damage annually. If an effective control strategy for these pests could be developed, it is estimated that the current market for effective nematicides is between 700 million and $1 billion each year worldwide. In this study, we report on the utilization of PVN technology to encapsulate the biological nematicide, abamectin (Abm), within the PVN's interior capsid (PVNAbm). Creating PVNAbm addresses Abm's issues of soil immobility while rendering a controlled release strategy for its bioavailability to root knot nematodes (RKNs

Arguments for the installation of small LWR nuclear power plants in developing countries

International Nuclear Information System (INIS)

Lezenik, B.

1977-01-01

The differences disclosed in the IAEA-Report ''Market Survey...'' before and after the drastic increase of the oil price in 1973 indicate most unequivocally the growing economic profits of the application of nuclear power plants with smaller output. The report furthermore demonstrates in clear terms the benefits of a long-term fuel arrangement as is applied for nuclear power plants. Following these basic considerations, according to which the construction of nuclear power plants appears to be reasonable, economically speaking, the next important criterion having priority, as far as the technical aspect is concerned, is the question concerning the largest possible unit to be integrated into the grid. So as to ensure a steady mains power supply, the structure of operating power plant types, their number and unit sizes as well as their controllability and load-following behavior have to be coordinated with one another individually. As an example for the nuclear power plant Borssele (450 MW - PWR) which has been in operation since 1973, basic control concepts are outlined which together with the load-following behavior of this reactor meet the grid requirements. This is to demonstrate the flexible application of this reactor type. Manufacturing and operating experience as well as the accumulated know-how concerning design and construction of large plants in the 1200/1300 MW class offer a broad basis for the standardization of the smaller LWR-plants. The experience gained with proven components and approved systems for the fully standardized 1200/1300 MW reactors equally guarantees operating reliability and availability, since differences in output are realized by means of additive modifications of the primary system components. A comparison with, and an interpretation of, the essential design data outline the progress achieved in the standardization process. So as to ensure as efficient as possible implementation of the construction procedure, and the application of

Containment for small pressurized water reactors

International Nuclear Information System (INIS)

Siler, W.C.; Marda, R.S.; Smith, W.R.

1977-01-01

Babcock and Wilcox Company has prepared studies under ERDA contract of small and intermediate size (313, 365 and 1200 MWt) PWR reactor plants, for industrial cogeneration or electric power generation. Studies and experience with nuclear plants in this size range indicate unfavorable economics. To offset this disadvantage, modular characteristics of an integral reactor and close-coupled vapor suppression containment have been exploited to shorten construction schedules and reduce construction costs. The resulting compact reactor/containment complex is illustrated. Economic studies to date indicate that the containment design and the innovative construction techniques developed to shorten erection schedules have been important factors in reducing estimated project costs, thus potentially making such smaller plants competetive with competing energy sources

Small Nuclear Technology and Market Entry

International Nuclear Information System (INIS)

Stewart, J S; Schock, R N; Brown, N W; Smith, C F

2002-01-01

An overview of energy-system projections into the new century leads to the conclusion that nuclear power will play a significant role. How significant a role will be determined by the marketplace. Within the range of nuclear-power technologies available, small nuclear-power plants of innovative design appear to fit the needs of a number of developing nations and states. Under similar financing options used by the airline industry and others, the capital requirement barrier that puts the nuclear industry at a disadvantage in deregulated markets could be reduced. These plants have the potential advantage of modularity, are proliferation-resistant, incorporate passive safety features, minimize waste, and could be cost-competitive with fossil-fuel plants

The using of alternative energy sources: the case of Small Hydroelectric Power Plants and the natural gas fuelled thermal electric power plants; O uso de fontes alternativas de energia: o caso das Pequenas Centrais Hidreletricas (PCHs) e das termoeletricas movidas a gas natural

Energy Technology Data Exchange (ETDEWEB)

Souza, Patricia Aparecida Pereira; Mauad, Frederico Fabio [Sao Paulo Univ., Sao Carlos, SP (Brazil). Escola de Engenharia. Centro de Recursos Hidricos e Ecologia Aplicada; Leme, Alessandro Andre [Sao Carlos Univ., SP (Brazil). Programa de Pos-graduacao em Ciencias Sociais; Valencio, Norma Felicidade Lopes da Silva [Sao Carlos Univ., SP (Brazil). Dept. de Ciencias Sociais

2002-07-01

This paper emphasizes the modifications occurred in the brazilian electric sector at the end of the twenty century. The work also highlight the alternative sources (Small hydroelectric and thermoelectric power plants) as the most feasible in the political and institutional scenery for the complementation of the generator park.

System design study of a membrane reforming hydrogen production plant using a small sized sodium cooled reactor

International Nuclear Information System (INIS)

Chikazawa, Y.; Konomura, M.; Hori, T.; Sato, H.; Uchida, S.

2004-01-01

In this study, a membrane reforming hydrogen production plant using a small sized sodium cooled reactor was designed as one of promising concepts. In the membrane reformer, methane and steam are reformed into carbon dioxide and hydrogen with sodium heat at a temperature 500 deg-C. In the equilibrium condition, steam reforming proceeds with catalyst at a temperature more than 800 deg-C. Using membrane reformers, the steam reforming temperature can be decreased from 800 to 500 deg-C because the hydrogen separation membrane removes hydrogen selectively from catalyst area and the partial pressure of hydrogen is kept much lower than equilibrium condition. In this study, a hydrogen and electric co-production plant has been designed. The reactor thermal output is 375 MW and 25% of the thermal output is used for hydrogen production (70000 Nm 3 /h). The hydrogen production cost is estimated to 21 yen/Nm 3 but it is still higher than the economical goal (17 yen/Nm 3 ). The major reason of the high cost comes from the large size of hydrogen separation reformers because of the limit of hydrogen separation efficiency of palladium membrane. A new highly efficient hydrogen separation membrane is needed to reduce the cost of hydrogen production using membrane reformers. There is possibility of multi-tube failure in the membrane reformers. In future study, a design of measures against tube failure and elemental experiments of reaction between sodium and reforming gas will be needed. (authors)

Small ring testing of a creep resistant material

International Nuclear Information System (INIS)

Hyde, C.J.; Hyde, T.H.; Sun, W.; Nardone, S.; De Bruycker, E.

2013-01-01

Many components in conventional and nuclear power plant, aero-engines, chemical plant etc., operate at temperatures which are high enough for creep to occur. These include steam pipes, pipe branches, gas and steam turbine blades, etc. The manufacture of such components may also require welds to be part of them. In most cases, only nominal operating conditions (i.e. pressure, temperatures, system load, etc.) are known and hence precise life predictions for these components are not possible. Also, the proportion of life consumed will vary from position to position within a component. Hence, non-destructive techniques are adopted to assist in making decisions on whether to repair, continue operating or replace certain components. One such approach is to test a small sample removed from the component to make small creep test specimens which can be tested to give information on the remaining creep life of the component. When such a small sample cannot be removed from the operating component, e.g. in the case of small components, the component can be taken out of operation in order to make small creep test specimens, the results from which can then be used to assist with making decisions regarding similar or future components. This paper presents a small creep test specimen which can be used for the testing of particularly strong and creep resistant materials, such as nickel-based superalloys

Demonstration of a Porous Tube Hydroponic System to Control Plant Moisture and Growth

Science.gov (United States)

Dreschel, T. W.; Hall, C. R.; Foster, T. E.

2003-01-01

Accurate remote detection of plant health indicators such as moisture, plant pigment concentrations, photosynthetic flux, and other biochemicals in canopies is a major goal in plant research. Influencing factors include complex interactions between wavelength dependent absorbing and scattering features from backgrounds as well as canopy biochemical and biophysical constituents. Accurately controlling these factors in outdoor field studies is difficult. Early testing of a porous tube plant culture system has indicated that plant biomass production, biomass partitioning, and leaf moisture of plants can be controlled by precisely managing the root water potential. Managing nutrient solution chemistry can also control plant pigments, biochemical concentrations, plant biomass production, and photosynthetic rates. A test bed was developed which utilized the porous tube technology with the intent of evaluating remote sensing systems, spectral analyses procedures, gas-exchange, and fluorescence measurements for their ability to detect small differences in plant water status. Spectral analysis was able to detect small differences in the mean leaf water content between the treatments. However these small differences were not detectable in the gas-exchange or fluorescence measurements.

Emissions from small scale combustion of pelletized wood fuels

International Nuclear Information System (INIS)

Bachs, A.

1998-01-01

Combustion of wood pellets in small scale heating systems with an effect below 20 kW has increased. During the winter season 1995/96 1500 small plants for heating houses are estimated to be in operation. Stack emissions from three pellet burners and two pellet stoves have been studied at laboratory. Different pellet qualities were tested. When the fraction of fines increased also the NO x emissions increased with about 10 %. As reference fuel 8 mm pellets was used. Tests with 6 mm pellets gave, in most cases, significant lower emissions of CO and THC. Eleven stoves, burners and boilers were studied in a field test. The results show that all the plants generally have higher emissions in the field than during conditions when the plants are adjusted with a stack gas monitoring instrument. A conclusion is that it is difficult for the operator to adjust the plant without a monitoring instrument. The emissions from the tested plants give an estimation of stack gas emissions from small scale pellet plants. The difference between the 'best' and 'worst' technologies is big. The span of emissions with the best technology to the worst is given below. The interval is concerning normal combustion . During abnormal conditions the emissions are on a significant higher level: * CO 80-1 000 mg/MJ; * Tar 0,3-19 mg/MJ; * THC (as methane equivalents) 2-100 mg/MJ; * NO x 50-70 mg/W;, and * Dust emissions 20-40 mg/MJ. Emissions from pellets heating are lower than from wood combustion and the best technology is close to the emission from oil burners. Wood and pellets have the same origin but the conditions to burn them in an environmental friendly way differ. Combustion of pellets could be improved through improved control of the air and fuel ratio that will create more stable conditions for the combustion

An approach to the investment analysis of small and medium hydro-power plants

DEFF Research Database (Denmark)

Forouzbakhsh, Farshid; Hosseini, S.M.H.; Vakilian, M.

2007-01-01

Hydro-power plants, as a part of infrastructure projects, play an important role in the economic-social development of countries. Sincea large amount of investment is needed for construction of these power plants, which appeared to be an obstacle in these developments,however it is possible...

Nuclear power plant and the host community

Energy Technology Data Exchange (ETDEWEB)

Olsson, G

1978-10-27

A councillor from a small Swedish community (Kaevlinge) in the vicinity of the Barsebaeck nuclear power plant describes the effects which the plant has had on neighbouring communities. The effect on the labour market has been small at Kaevlinge, both during routine operation and construction phases. This is however, a fairly densely populated area with a population of half a million in a radius of 30 km. The situation is different at Oskarshamn or Oesthammar. Neither has there been any special economic benefit, due to Swedish taxation laws. There has been little local anxiety due to the proximity of the nuclear power plant. Certain local planning problems have been caused by restricted zones and power cables. Cooperation between the local authorities and the utility has been good.

Small scale pelletizing equipment for agriculture; Smaaskalig pelleteringsanlaeggning foer lantbruket

Energy Technology Data Exchange (ETDEWEB)

Paulrud, Susanne (The Swedish Environmental Research Inst. Ltd., Stockholm (Sweden)); Wallin, Mikael (Sweden Powers Chippers AB, Boraas (Sweden))

2009-06-15

Refining agricultural raw materials is one way for farmers to increase the value of their products. For example, briquettes or pellets made from straw, reed canary grass or hemp can sell for a higher price than in loose or baled forms. The aim of this project was to develop and build a plant for small-scale production of pellets on the farm. Working together with the farmer, the plant would then be tested and adapted for small-scale production of pellets from straw, reed canary grass and hemp. The project also aimed to investigate and summarise suitable systems and solutions for breaking up bales in preparation for use in the pellets module. A pelleting system has been developed and built as a container module (measuring 6 x 2.80 x 2.50 m) by Sweden Power Chippers (SPC). The container system includes a fuel store with push floor, a grinder, an SPC pellet press (pp150, capacity 150 kg/hour for woodbased material), a conveyor belt and a cooling system. The practical operation of the plant was tested on two Swedish farms: Laattra gaard in Vingaaker and Ek gaard in Vara. The bales were broken up in preparation for pelleting using a straw mill of model Tomahawk 505M. The project has demonstrated that the SPC plant has the capacity to be used for agricultural pelleting of fuels from straw, canary reed grass and hemp. Some modification and continued adjustment of the feed system for the fuel remains to be done in order to optimise and ensure the reliability of the pelleting process. A certain amount of modifications to the plant is required to enable cost-effective transportation between different locations. Tests showed that each batch of fuel was unique, even from the same raw material, and that optimisation of the dies is necessary for each specific case. Training is required to run the plant. The farmers have been able to run the plant themselves, for example, starting up the plant, changing the sieve on the grinder, changing dies etc. In order for such small

Contents of some heavy metals in plants from Saginaw Bay (Lake Huron) and some small lakes in wilderness areas of Michigan's Upper Peninsula as analyzed by neutron activation analysis

International Nuclear Information System (INIS)

Wells, J.R.; Kaufman, P.B.; Jones, J.D.; Estabrook, G.F.; Ghosheh, N.S.; Michigan Univ., Ann Arbor; Eastern Michigan University, Ypsilanti

1982-01-01

The highest concentrations of heavy metals occured in plants collected near the mouth of the Saginaw River. The alga, Cladophora sp., and the flowering plant, Typha augustifolia (cat-tail), are notable for the high concentration of heavy metals. In addition, several other species that were sampled from small lakes in Michigan's Upper Peninsula contained higher concentrations of certain metals (Ba, Cr, Rb) than from any samples obtained from Saginaw Bay. Different organs of the same species, or of the same plant, such as cut-tail, vary widely in concentrations of the same element. A computer-derived analysis of our data is presented, and the implications of our results as they relate to pollution by heavy metals in fresh-water lakes is discussed. (author)

Canadian small-scale hydroelectric plant manual: Quebec region, feasibility study for domestic installations. Manuel canadien de centrale hydroelectrique a faible puissance: Region du Quebec, etude de faisabilite pour installations domestiques

Energy Technology Data Exchange (ETDEWEB)

Proulx, S; Tung, T

1989-11-01

A manual is presented for evaluating the feasibility of domestic-scale hydropower plants, with reference to Quebec conditions. Procedures are given for determining energy needs, and the flow conditions and electricity generating potential of a site. The laws which regulate small hydro plants in Quebec are outlined. The types of turbines and associated electrical equipment are discussed, along with criteria for their selection according to application. The economic analysis of a proposed project is then described, and a list of documents which need to be prepared is included, as well as a glossary. A case study of a 50-kW plant installed at a Quebec restaurant is illustrated. 6 refs., 24 figs., 1 tab.

Market for small waste gasification projects - preliminary scoping study

International Nuclear Information System (INIS)

1999-01-01

This report presents the findings of a market analysis for small waste gasification/pyrolysis plant in the UK. The overall objectives of the study are to assess the potential merits in establishing a demonstration plant in the UK, and to identify the size, profile and characteristics of the potential market based on municipal solid waste (MSW) feedstock. (author)

Trade-offs Between Electricity Production from Small Hydropower Plants and Ecosystem Services in Alpine River Basins

Science.gov (United States)

Meier, Philipp; Schwemmle, Robin; Viviroli, Daniel

2015-04-01

The need for a reduction in greenhouse gas emissions and the decision to phase out nuclear power plants in Switzerland and Germany increases pressure to develop the remaining hydropower potential in Alpine catchments. Since most of the potential for large reservoirs is already exploited, future development focusses on small run-of-the-river hydropower plants (SHP). Being considered a relatively environment-friendly electricity source, investment in SHP is promoted through subsidies. However, SHP can have a significant impact on riverine ecosystems, especially in the Alpine region where residual flow reaches tend to be long. An increase in hydropower exploitation will therefore increase pressure on ecosystems. While a number of studies assessed the potential for hydropower development in the Alps, two main factors were so far not assessed in detail: (i) ecological impacts within a whole river network, and (ii) economic conditions under which electricity is sold. We present a framework that establishes trade-offs between multiple objectives regarding environmental impacts, electricity production and economic evaluation. While it is inevitable that some ecosystems are compromised by hydropower plants, the context of these impacts within a river network should be considered when selecting suitable sites for SHP. From an ecological point of view, the diversity of habitats, and therefore the diversity of species, should be maintained within a river basin. This asks for objectives that go beyond lumped parameters of hydrological alteration, but also consider habitat diversity and the spatial configuration. Energy production in run-of-the-river power plants depends on available discharge, which can have large fluctuations. In a deregulated electricity market with strong price variations, an economic valuation should therefore be based on the expected market value of energy produced. Trade-off curves between different objectives can help decision makers to define policies

Small Wind Turbine Technology Assessment

International Nuclear Information System (INIS)

Avia Aranda, F.; Cruz Cruz, I.

1999-01-01

The result of the study carried out under the scope of the ATYCA project Test Plant of Wind Systems for Isolated Applications, about the state of art of the small wind turbine technology (wind turbines with swept area smaller than 40 m 2 ) is presented. The study analyzes the collected information on 60 models of wind turbines from 23 manufacturers in the worldwide market. Data from Chinese manufacturers, that have a large participation in the total number of small wind turbines in operation, are not included, due to the unavailability of the technical information. (Author) 15 refs

Plant Size and Competitive Dynamics along Nutrient Gradients.

Science.gov (United States)

Goldberg, Deborah E; Martina, Jason P; Elgersma, Kenneth J; Currie, William S

2017-08-01

Resource competition theory in plants has focused largely on resource acquisition traits that are independent of size, such as traits of individual leaves or roots or proportional allocation to different functions. However, plants also differ in maximum potential size, which could outweigh differences in module-level traits. We used a community ecosystem model called mondrian to investigate whether larger size inevitably increases competitive ability and how size interacts with nitrogen supply. Contrary to the conventional wisdom that bigger is better, we found that invader success and competitive ability are unimodal functions of maximum potential size, such that plants that are too large (or too small) are disproportionately suppressed by competition. Optimal size increases with nitrogen supply, even when plants compete for nitrogen only in a size-symmetric manner, although adding size-asymmetric competition for light does substantially increase the advantage of larger size at high nitrogen. These complex interactions of plant size and nitrogen supply lead to strong nonlinearities such that small differences in nitrogen can result in large differences in plant invasion success and the influence of competition along productivity gradients.

Effect of water purification process in radioactive content: analysis on small scale purification plants; Efecto del proceso de purificacion de agua en el contenido radiactivo: analisis en plantas purificadoras a pequena escala

Energy Technology Data Exchange (ETDEWEB)

Lopez del Rio, H.; Quiroga S, J. C.; Davila R, J. I.; Mireles G, F. [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98000, Zacatecas (Mexico)], e-mail: hlopez@uaz.edu.mx

2009-10-15

Water from small scale purification plants is a low cost alternative for consumers in comparison to the bottled commercial presentations. Because of its low cost per liter, the consumption of this product has increased in recent years, stimulating in turn the installation of purification systems for these small businesses. The purpose of this study was to estimate the efficiency of small scale purification systems located in the cities of Zacatecas and Guadalupe, Zacatecas, to reduce the radioactive content of water. It was measured the total alpha and beta activity in water samples of entry and exit to process, through the liquid scintillation technique. In general it was observed that the process is more efficient in removing alpha that beta activity. The fraction of total alpha activity removed varied between 27 and 100%, while between 0 and 77% of the total beta activity was removed by the analyzed plants. In all cases, the total radioactivity level was lower than the maximum permissible value settled by the official mexican standard for drinking water. (Author)

Biomass from agriculture in small-scale combined heat and power plants - A comparative life cycle assessment

International Nuclear Information System (INIS)

Kimming, M.; Sundberg, C.; Nordberg, A.; Baky, A.; Bernesson, S.; Noren, O.; Hansson, P.-A.

2011-01-01

Biomass produced on farm land is a renewable fuel that can prove suitable for small-scale combined heat and power (CHP) plants in rural areas. However, it can still be questioned if biomass-based energy generation is a good environmental choice with regards to the impact on greenhouse gas emissions, and if there are negative consequences of using of agricultural land for other purposes than food production. In this study, a simplified life cycle assessment (LCA) was conducted over four scenarios for supply of the entire demand of power and heat of a rural village. Three of the scenarios are based on utilization of biomass in 100 kW (e) combined heat and power (CHP) systems and the fourth is based on fossil fuel in a large-scale plant. The biomass systems analyzed were based on 1) biogas production with ley as substrate and the biogas combusted in a microturbine, 2) gasification of willow chips and the product gas combusted in an IC-engine and 3) combustion of willow chips for a Stirling engine. The two first scenarios also require a straw boiler. The results show that the biomass-based scenarios reduce greenhouse gas emissions considerably compared to the scenario based on fossil fuel, but have higher acidifying emissions. Scenario 1 has by far the best performance with respect to global warming potential and the advantage of utilizing a byproduct and thus not occupying extra land. Scenario 2 and 3 require less primary energy and less fossil energy input than 1, but set-aside land for willow production must be available. The low electric efficiency of scenario 3 makes it an unsuitable option.

Development of a screening procedure for vibrational fatigue in small bore piping

International Nuclear Information System (INIS)

Smith, J.K.; Riccardella, P.C.; Gosselin, S.R.

1995-01-01

Approximately 80% of the documented fatigue failures in nuclear power plants are caused by high cycle vibrational fatigue. These failures typically occur in socket welded pipe fittings in small bore piping (2 in. nominal diameter and smaller). These failures have been unexpected, and have caused costly, unscheduled outages in some cases. In order to reduce the number of vibrational fatigue failures in operating nuclear power plants, a vibrational fatigue screening procedure has been developed under Electric Power Research Institute (EPRI) sponsorship. The purpose of this paper is to describe this procedure, and to discuss topics related to vibrational fatigue failures. These topics include sources of vibration in nuclear power plants, the effect of socket welds on vibrational fatigue failures, vibrational fatigue screening criteria for small bore piping systems, and good design practices for reducing the number of vibrational fatigue failures in small bore piping

Soil inoculation method determines the strength of plant-soil interactions

NARCIS (Netherlands)

Voorde, van de T.F.J.; Ruijten, M.; Putten, van der W.H.; Bezemer, T.M.

2012-01-01

There is increasing evidence that interactions between plants and biotic components of the soil influence plant productivity and plant community composition. Many plant–soil feedback experiments start from inoculating relatively small amounts of natural soil to sterilized bulk soil. These soil

Small scale demand type neon liquefaction plant

International Nuclear Information System (INIS)

Dube, W.P.; Slifka, A.J.; Bitsy, R.M.; Sparks, L.L.; Johnson, K.B.

1990-01-01

Low-temperature measurement of the thermal conductivity of insulating materials is generally made using a boil-off calorimetry technique involving liquid hydrogen (LH2). Liquid neon (LNe) has nearly the same normal boiling point as LH2, but has a much larger heat of vaporization, allowing extended run times. The main drawback of using LNe has been its excessive cost; $170.00 versus $1.50/l for LH2 (1989 prices). A neon liquefaction plant has been designed and constructed to capture, purify, and refrigerate the neon boil-off from calorimetry experiments. Recycling the neon reduces operating costs to approximately $20/l. The system consists of a purification section, a heat exchanger, LNe and LH2 storage dewars, and a fully automated control system. After purification, neon is liquified in the heat exchanger by LH2 flowing countercurrently through stainless steel cooling coils. Hydrogen flow is automatically adjusted to keep the neon at its normal saturation temperature, 27 K. The liquid neon is then stored in a dewar placed directly below the heat exchanger

Capturing Insects and Student Interest: First Graders Learn about Unusual Plants in Their Area in This Multimodal Investigation of Carnivorous Plants

Science.gov (United States)

Bradbury, Leslie; Wilson, Rachel; Pepper, Nancy; Ledford, Mitzi

2016-01-01

Most plants are able to obtain all of the nutrients that they need from air, water, and soil; however, this is not true of carnivorous plants. Because they tend to live in boggy soils where there are small amounts of nitrogen, carnivorous plants have developed specialized structures that enable them to lure and capture insects and sometimes other…

Leaf spray: direct chemical analysis of plant material and living plants by mass spectrometry.

Science.gov (United States)

Liu, Jiangjiang; Wang, He; Cooks, R Graham; Ouyang, Zheng

2011-10-15

The chemical constituents of intact plant material, including living plants, are examined by a simple spray method that provides real-time information on sugars, amino acids, fatty acids, lipids, and alkaloids. The experiment is applicable to various plant parts and is demonstrated for a wide variety of species. An electrical potential is applied to the plant and its natural sap, or an applied solvent generates an electrospray that carries endogenous chemicals into an adjacent benchtop or miniature mass spectrometer. The sharp tip needed to create a high electric field can be either natural (e.g., bean sprout) or a small nick can be cut in a leaf, fruit, bark, etc. Stress-induced changes in glucosinolates can be followed on the minute time scale in several plants, including potted vegetables. Differences in spatial distributions and the possibility of studying plant metabolism are demonstrated. © 2011 American Chemical Society

SLUDGE TREATMENT PROJECT COST COMPARISON BETWEEN HYDRAULIC LOADING AND SMALL CANISTER LOADING CONCEPTS

Energy Technology Data Exchange (ETDEWEB)

GEUTHER J; CONRAD EA; RHOADARMER D

2009-08-24

The Sludge Treatment Project (STP) is considering two different concepts for the retrieval, loading, transport and interim storage of the K Basin sludge. The two design concepts under consideration are: (1) Hydraulic Loading Concept - In the hydraulic loading concept, the sludge is retrieved from the Engineered Containers directly into the Sludge Transport and Storage Container (STSC) while located in the STS cask in the modified KW Basin Annex. The sludge is loaded via a series of transfer, settle, decant, and filtration return steps until the STSC sludge transportation limits are met. The STSC is then transported to T Plant and placed in storage arrays in the T Plant canyon cells for interim storage. (2) Small Canister Concept - In the small canister concept, the sludge is transferred from the Engineered Containers (ECs) into a settling vessel. After settling and decanting, the sludge is loaded underwater into small canisters. The small canisters are then transferred to the existing Fuel Transport System (FTS) where they are loaded underwater into the FTS Shielded Transfer Cask (STC). The STC is raised from the basin and placed into the Cask Transfer Overpack (CTO), loaded onto the trailer in the KW Basin Annex for transport to T Plant. At T Plant, the CTO is removed from the transport trailer and placed on the canyon deck. The CTO and STC are opened and the small canisters are removed using the canyon crane and placed into an STSC. The STSC is closed, and placed in storage arrays in the T Plant canyon cells for interim storage. The purpose of the cost estimate is to provide a comparison of the two concepts described.

SLUDGE TREATMENT PROJECT COST COMPARISON BETWEEN HYDRAULIC LOADING AND SMALL CANISTER LOADING CONCEPTS