A model of milk production in lactating dairy cows in relation to energy and nitrogen dynamics.

Science.gov (United States)

Johnson, I R; France, J; Cullen, B R

2016-02-01

A generic daily time-step model of a dairy cow, designed to be included in whole-system pasture simulation models, is described that includes growth, milk production, and lactation in relation to energy and nitrogen dynamics. It is a development of a previously described animal growth and metabolism model that describes animal body composition in terms of protein, water, and fat, and energy dynamics in relation to growth requirements, resynthesis of degraded protein, and animal activity. This is further developed to include lactation and fetal growth. Intake is calculated in relation to stage of lactation, pasture availability, supplementary feed, and feed quality. Energy costs associated with urine N excretion and methane fermentation are accounted for. Milk production and fetal growth are then calculated in relation to the overall energy and nitrogen dynamics. The general behavior of the model is consistent with expected characteristics. Simulations using the model as part of a whole-system pasture simulation model (DairyMod) are compared with experimental data where good agreement between pasture, concentrate and forage intake, as well as milk production over 3 consecutive lactation cycles, is observed. The model is shown to be well suited for inclusion in large-scale system simulation models. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Strategy for designing stable and powerful nitrogen-rich high-energy materials by introducing boron atoms.

Science.gov (United States)

Wu, Wen-Jie; Chi, Wei-Jie; Li, Quan-Song; Li, Ze-Sheng

2017-06-01

One of the most important aims in the development of high-energy materials is to improve their stability and thus ensure that they are safe to manufacture and transport. In this work, we theoretically investigated open-chain N 4 B 2 isomers using density functional theory in order to find the best way of stabilizing nitrogen-rich molecules. The results show that the boron atoms in these isomers are aligned linearly with their neighboring atoms, which facilitates close packing in the crystals of these materials. Upon comparing the energies of nine N 4 B 2 isomers, we found that the structure with alternating N and B atoms had the lowest energy. Structures with more than one nitrogen atom between two boron atoms had higher energies. The energy of N 4 B 2 increases by about 50 kcal/mol each time it is rearranged to include an extra nitrogen atom between the two boron atoms. More importantly, our results also show that boron atoms stabilize nitrogen-rich molecules more efficiently than carbon atoms do. Also, the combustion of any isomer of N 4 B 2 releases more heat than the corresponding isomer of N 4 C 2 does under well-oxygenated conditions. Our study suggests that the three most stable N 4 B 2 isomers (BN13, BN24, and BN34) are good candidates for high-energy molecules, and it outlines a new strategy for designing stable boron-containing high-energy materials. Graphical abstract The structural characteristics, thermodynamic stabilities, and exothermic properties of nitrogen-rich N 4 B 2 isomers were investigated by means of density functional theory.

3D analysis of the morphology and spatial distribution of nitrogen in nitrogen-doped carbon nanotubes by energy-filtered transmission electron microscopy tomography.

Science.gov (United States)

Florea, Ileana; Ersen, Ovidiu; Arenal, Raul; Ihiawakrim, Dris; Messaoudi, Cédric; Chizari, Kambiz; Janowska, Izabela; Pham-Huu, Cuong

2012-06-13

We present here the application of the energy-filtered transmission electron microscopy (EFTEM) in the tomographic mode to determine the precise 3D distribution of nitrogen within nitrogen-doped carbon nanotubes (N-CNTs). Several tilt series of energy-filtered images were acquired on the K ionization edges of carbon and nitrogen on a multiwalled N-CNT containing a high amount of nitrogen. Two tilt series of carbon and nitrogen 2D maps were then calculated from the corresponding energy-filtered images by using a proper extraction procedure of the chemical signals. Applying iterative reconstruction algorithms provided two spatially correlated C and N elemental-selective volumes, which were then simultaneously analyzed with the shape-sensitive reconstruction deduced from Zero-Loss recordings. With respect to the previous findings, crucial information obtained by analyzing the 3D chemical maps was that, among the two different kind of arches formed in these nanotubes (transversal or rounded ones depending on their morphology), the transversal arches contain more nitrogen than do the round ones. In addition, a detailed analysis of the shape-sensitive volume allowed the observation of an unexpected change in morphology along the tube axis: close to the round arches (with less N), the tube is roughly cylindrical, whereas near the transversal ones (with more N), its shape changes to a prism. This relatively new technique is very powerful in the material science because it combines the ability of the classical electron tomography to solve 3D structures and the chemical selectivity of the EFTEM imaging.

Energy assessment of nitrogen variable rate fertilization on wheat; Analise energetica da aplicacao de nitrogenio em taxa variavel em trigo

Energy Technology Data Exchange (ETDEWEB)

Colaco, A.F.; Karam, E.H.; Romanelli, T.L.; Molin, J.P. [Escola Superior de Agricultura Luiz Queiroz (ESALQ/USP), Piracicaba, SP (Brazil). Dept. de Engenharia de Biossistemas], Email: andrecolaco@usp.br; Povh, F.P. [Fundacao ABC Pesquisa e Desenvolvimento Agropecuario, Castro, PR (Brazil)

2011-07-01

Precision Agriculture (PA) is a technique that can reduce the inputs utilization in agriculture production, including the nitrogen fertilizer consume. Great importance is given to this fertilizer, due to its contribution on energy input in agriculture. Methodologies based on the calculation of energy flow of agriculture systems are capable to identify management practices that use energy more efficiently. So, this study's objective is to evaluate the variable-rate nitrogen fertilization on wheat, using energy assessment. This study was carried on in two wheat fields, in which the fertilization was done adopting strips alternated by conventional method (single nitrogen dose) and by nitrogen variable-rate technology. Thus, the input and output energy in the system, energy balance, energy return on investment (EROI) and incorporated energy were determined for each geo-referenced point within the fields. Results showed that less energy was demanded when using variable-rate technology, due to the nitrogen saving, providing greater energy balance, EROI and lower incorporated energy on the areas managed using PA. The energy assessment showed to be an important tool to evaluate systems that use PA, because it is capable of monitoring crops energy potential. (author)

Nitrogen requirements of commercial wine yeast strains during fermentation of a synthetic grape must.

Science.gov (United States)

Gutiérrez, Alicia; Chiva, Rosana; Sancho, Marta; Beltran, Gemma; Arroyo-López, Francisco Noé; Guillamon, José Manuel

2012-08-01

Nitrogen deficiencies in grape musts are one of the main causes of stuck or sluggish wine fermentations. Currently, the most common method for dealing with nitrogen-deficient fermentations is adding supplementary nitrogen (usually ammonium phosphate). However, it is important to know the specific nitrogen requirement of each strain, to avoid excessive addition that can lead to microbial instability and ethyl carbamate accumulation. In this study, we aimed to determine the effect of increasing nitrogen concentrations of three different nitrogen sources on growth and fermentation performance in four industrial wine yeast strains. This task was carried out using statistical modeling techniques. The strains PDM and RVA showed higher growth-rate and maximum population size and consumed nitrogen much more quickly than strains ARM and TTA. Likewise, the strains PDM and RVA were also the greatest nitrogen demanders. Thus, we can conclude that these differences in nitrogen demand positively correlated with higher growth rate and higher nitrogen uptake rate. The most direct effect of employing an adequate nitrogen concentration is the increase in biomass, which involves a higher fermentation rate. However, the impact of nitrogen on fermentation rate is not exclusively due to the increase in biomass because the strain TTA, which showed the worst growth behavior, had the best fermentation activity. Some strains may adapt a strategy whereby fewer cells with higher metabolic activity are produced. Regarding the nitrogen source used, all the strains showed the better and worse fermentation performance with arginine and ammonium, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

Studies on growth, nitrogen and energy metabolism in rats

DEFF Research Database (Denmark)

Thorbek, G; Chwalibog, André; Eggum, B O

1982-01-01

Feed intake, growth, nitrogen retention and energy metabolism were measured in 12 male Wistar rats fed ad lib. for 14 weeks with non-purified diets. The feed intake increased rapidly in 4 weeks time from 16 g/d to 25 g/d, and then it was constant in the following 10 weeks. In relation to metabolic...

Corrosion behavior of low energy, high temperature nitrogen ion ...

Indian Academy of Sciences (India)

Corrosion behavior of low energy, high temperature nitrogen ion-implanted AISI 304 stainless steel. M GHORANNEVISS1, A SHOKOUHY1,∗, M M LARIJANI1,2,. S H HAJI HOSSEINI 1, M YARI1, A ANVARI4, M GHOLIPUR SHAHRAKI1,3,. A H SARI1 and M R HANTEHZADEH1. 1Plasma Physics Research Center, Science ...

Endogenous Losses of Nitrogen and Protein Requirement for ...

African Journals Online (AJOL)

Four fistulated and four intact West African dwarf wether sheep, maintained on hay and concentrate supplements were used for a study of metabolic faecal nitrogen (MEN) and endogenous urinary nitrogen (EUN). The composition of the faecal losses was examined. The values obtained enabled calculation of nitrogen ...

Energy requirement and economic analysis of citrus production in Turkey

Energy Technology Data Exchange (ETDEWEB)

Ozkan, Burhan E-mail: bozkan@akdeniz.edu.tr; Akcaoz, Handan; Karadeniz, Feyza

2004-07-01

The aim of this research was to examine the energy requirements of the inputs and output in citrus production in the Antalya province of Turkey. Data for the production of citrus fruits (orange, lemon and mandarin) were collected from 105 citrus farms by using a face to face questionnaire method. The research results revealed that lemon production was the most energy intensive among the three fruits investigated. The energy input of chemical fertilizer (49.68%), mainly nitrogen, has the biggest share in the total energy inputs followed by Diesel (30.79%). The lemon production consumed a total of 62 977.87 MJ/ha followed by orange and mandarin with 60 949.69 and 48 838.17 MJ/ha, respectively. The energy ratios for orange, mandarin and lemon were estimated to be 1.25, 1.17 and 1.06, respectively. On average, the non-renewable form of energy input was 95.90% of the total energy input used in citrus production compared to only 3.74% for the renewable form. The benefit-cost ratio was the highest in orange production (2.37) followed by lemon. The results indicate that orange production in the research area is most remunerative to growers compared to lemon and mandarin.

Carbon and nitrogen trade-offs in biomass energy production

Energy Technology Data Exchange (ETDEWEB)

Cucek, Lidija; Klemes, Jiri Jaromir [University of Pannonia, Centre for Process Integration and Intensification (CPI" 2), Research Institute of Chemical and Process Engineering, Faculty of Information Technology, Veszprem (Hungary); Kravanja, Zdravko [University of Maribor, Faculty of Chemistry and Chemical Engineering, Maribor (Slovenia)

2012-06-15

This contribution provides an overview of carbon (CFs) and nitrogen footprints (NFs) concerning their measures and impacts on the ecosystem and human health. The adversarial relationship between them is illustrated by the three biomass energy production applications, which substitute fossil energy production applications: (i) domestic wood combustion where different fossil energy sources (natural gas, coal, and fuel oil) are supplemented, (ii) bioethanol production from corn grain via the dry-grind process, where petrol is supplemented, and (iii) rape methyl ester production from rape seed oil via catalytic trans-esterification, where diesel is supplemented. The life cycle assessment is applied to assess the CFs and NFs resulting from different energy production applications from 'cradle-to-grave' span. The results highlighted that all biomass-derived energy generations have lower CFs and higher NFs whilst, on the other hand, fossil energies have higher CFs and lower NFs. (orig.)

Adaptations of hepatic amino acid uptake and net utilisation contributes to nitrogen economy or waste in lambs fed nitrogen- or energy-deficient diets.

Science.gov (United States)

Kraft, G; Ortigues-Marty, I; Durand, D; Rémond, D; Jardé, T; Bequette, B; Savary-Auzeloux, I

2011-04-01

We investigated the effect of relative changes in dietary nitrogen (N) and energy supply and the subsequent variations in net portal appearance (NPA) of nitrogenous and energy nutrients on the net amino acid (AA) uptake by the liver and net N supply to the peripheral tissues. Six lambs were catheterised across the splanchnic tissues and received, in a replicated Latin square, one of three dietary treatments. The diets were formulated to either match the requirements of N and energy (C), or supply only 0.8 of the N requirement (LN) or 0.8 of the energy requirement (LE). Net fluxes of AA and urea-N were measured across the portal-drained viscera, and estimation of arterial hepatic flow allowed the estimation of hepatic fluxes. Catheters were implanted into the portal and hepatic veins as well as in the abdominal aorta for the measurement of AA fluxes. Animals fed the LN diet showed more efficient N retention (0.59 of digested N) than did the C and LE diet (0.50 and 0.33, respectively; P < 0.001). The NPA of total AA-N for the LN diet was only 0.60 of the value measured for the control (C) diet (P < 0.01). Despite this, the total estimated AA-N net splanchnic fluxes were not significantly different across the three diets (3.3, 1.9 and 2.6 g total AA-N/day for C, LN and LE, respectively, P = 0.52). Thus, different metabolic regulations must have taken place across the liver between the three experimental diets. A combination of decreased net uptake of total AA-N by the liver of animals in the LN diet (0.61 of the C diet; P = 0.002) and reduced urinary urea-N production (0.52 of the C diet; P = 0.001) spared AA from catabolism in the LN diet relative to the other two diets. For the LE diet, the urinary urea-N output was 1.3 times the value of the C diet (P = 0.01). This may relate to an increased catabolism of AA by the muscle and/or, to a lesser extent, to an increased utilisation of AA for gluconeogenesis in the liver. These effects may explain the reduced whole body

Food, Feed and Fuel: a Story About Nitrogen

Science.gov (United States)

Galloway, J. N.; Burke, M. B.; Mooney, H. A.; Steinfeld, H.

2008-12-01

Humans obtain metabolic energy by eating food. Nitrogen is required to grow food, but natural supplies of N for human purposes have been inadequate since the beginning of the twentieth century. The Haber-Bosch process now provides a virtually inexhaustible supply of nitrogen, limited primarily by the cost of energy. However, most nitrogen used in food production is lost to the environment, where it cascades through environmental reservoirs contributing to many of the major environmental issues of the day. Furthermore, growing international trade in nitrogen-containing commodities is increasingly replacing wind and water as an important international transporter of nitrogen around the globe. Finally, the rapid growth in crop-based biofuels, and its attendant effects on the global production and trade of all agricultural commodities, could greatly affect global patterns of N use and loss. In the light of the findings above, this paper examines the role of nitrogen in food, feed and fuel production. It describes the beneficial consequences for food production and the negative consequences associated with the commodity nitrogen cascade and the environmental nitrogen cascade. The paper reviews estimates of future projections of nitrogen demands for food and fuel, including the impact of changing diets in the developing world. The paper concludes by presenting the potential interactions among global change, agricultural production and the nitrogen and carbon cycles.

Studies on utilization of nitrogen-fixing bacteria for saving energy; Chisso koteikin no katsuyo ni yoru sho energy no kenkyu

Energy Technology Data Exchange (ETDEWEB)

Uozumi, T; Koyama, R; Horiuchi, M; Hidaka, M; Masaki, H [The University of Tokyo, Tokyo (Japan); Shigematsu, T; Inoue, A [New Energy and Industrial Technology Development Organization, Tokyo, (Japan)

1997-02-01

This paper describes analysis and enhancement of nitrogen-fixing gene of rice root bacteria, such as Klebsiella oxytoca, Azospirillum lipoferumn and Sphingomonas paucimobilis, for realizing energy saving through conservation of nitrogenous fertilizers. For K. oxytoca, modified strain R-16 was developed, which can fix nitrogen effectively even in the presence of NH4{sup +}. Nitrogen-fixing ability of A. lipoferumn depends on the activity control by the modification of nitrogen-fixing enzyme as well as on the adjustment of transcription level by the transcription activating gene, nifA. The control gene relating to the above was analyzed by making clones. As a result, a modified strain TAl without the control by NH4{sup +} was developed. The R-16 and TAl strains were inoculated into rice sterile-cultured without nitrogen. Consequently, inoculated strains were settled in the root, which resulted in the increased vegetation weight of plant to two times heavier than that without inoculation. 9 refs.

High Energy Cutting and Stripping Utilizing Liquid Nitrogen

Science.gov (United States)

Hume, Howard; Noah, Donald E.; Hayes, Paul W.

2005-01-01

The Aerospace Industry has endeavored for decades to develop hybrid materials that withstand the rigors of mechanized flight both within our atmosphere and beyond. The development of these high performance materials has led to the need for environmentally friendly technologies for material re-work and removal. The NitroJet(TM) is a fluid jet technology that represents an evolution of the widely used, large-scale water jet fluid jet technology. It involves the amalgamation of fluid jet technology and cryogenics technology to create a new capability that is applicable where water jet or abrasive jet (water jet plus entrained abrasive) are not suitable or acceptable because of technical constraints such as process or materials compatibility, environmental concerns and aesthetic or legal requirements. The NitroJet(TM) uses ultra high-pressure nitrogen to cut materials, strip numerous types of coatings such as paint or powder coating, clean surfaces and profile metals. Liquid nitrogen (LN2) is used as the feed stream and is pressurized in two stages. The first stage pressurizes sub cooled LN2 to an intermediate pressure of between 15,000 and 20,000 psi at which point the temperature of the LN2 is about -250 F. The discharge from this stage is then introduced as feed to a dual intensifier system, which boosts the pressure from 15,000 - 20,000 psi up to the maximum operating pressure of 55,000 psi. A temperature of about -220 F is achieved at which point the nitrogen is supercritical. In this condition the nitrogen cuts, strips and abrades much like ultra high-pressure water would but without any residual liquid to collect, remove or be contaminated. Once the nitrogen has performed its function it harmlessly flashes back into the atmosphere as pure nitrogen gas. The system uses heat exchangers to control and modify the temperature of the various intake and discharge nitrogen streams. Since the system is hydraulically operated, discharge pressures can be easily varied over

The Effect of Percentage of Nitrogen in Plasma Gas on Nitrogen ...

African Journals Online (AJOL)

Increase in nitrogen percent in the plasma gas results in increased content of dissociated nitrogen and molecular nitrogen possessing excess vibrational energy and therefore the increased solution of nitrogen in the liquid iron. It would appear that above 35% nitrogen in the plasma gas, frequency of collisions of species in ...

Ultra-shallow arsenic implant depth profiling using low-energy nitrogen beams

International Nuclear Information System (INIS)

Fearn, Sarah; Chater, Richard; McPhail, David

2004-01-01

Sputtering of silicon by low-energy nitrogen primary ion beams has been studied by a number of authors to characterize the altered layer, ripple formation and the sputtered yields of secondary ions [Surf. Sci. 424 (1999) 299; Appl. Phys. A: Mater. Sci. Process 53 (1991) 179; Appl. Phys. Lett. 73 (1998) 1287]. This study examines the application of low-energy nitrogen primary ion beams for the possible depth profiling of ultra-shallow arsenic implants into silicon. The emphasis of this work is on the matrix silicon signals in the pre-equilibrium surface region that are used for dose calibration. Problems with these aspects of the concentration depth profiling can give significant inconsistencies well outside the error limits of the quoted dose for the arsenic implantation as independently verified by CV profiling. This occurs during depth profiling with either oxygen primary ion beams (with and without oxygen leaks) or cesium primary ion beams

Nitrogen Balance and Protein Requirements for Critically Ill Older Patients

Directory of Open Access Journals (Sweden)

Roland N. Dickerson

2016-04-01

Full Text Available Critically ill older patients with sarcopenia experience greater morbidity and mortality than younger patients. It is anticipated that unabated protein catabolism would be detrimental for the critically ill older patient. Healthy older subjects experience a diminished response to protein supplementation when compared to their younger counterparts, but this anabolic resistance can be overcome by increasing protein intake. Preliminary evidence suggests that older patients may respond differently to protein intake than younger patients during critical illness as well. If sufficient protein intake is given, older patients can achieve a similar nitrogen accretion response as younger patients even during critical illness. However, there is concern among some clinicians that increasing protein intake in older patients during critical illness may lead to azotemia due to decreased renal functional reserve which may augment the propensity towards worsened renal function and worsened clinical outcomes. Current evidence regarding protein requirements, nitrogen balance, ureagenesis, and clinical outcomes during nutritional therapy for critically ill older patients is reviewed.

Effects of varying dietary zinc levels on energy and nitrogen ...

African Journals Online (AJOL)

Parameters determined were dry matter intake (DMI), energy utilization and nitrogen utilization. The mean±SE of Panicum maximum, Andropogon gayanus, Pennisetum purpureum, Leucaena leucocephala and Gliricidia sepium, contained 31.2±5.0; 29.1± 3.0;34.6± 6.0; 45.0± 5.0 and 47.1± 4.0mg Zn/kg DM respectively.

Canadian energy standards : residential energy code requirements

Energy Technology Data Exchange (ETDEWEB)

Cooper, K. [SAR Engineering Ltd., Burnaby, BC (Canada)

2006-09-15

A survey of residential energy code requirements was discussed. New housing is approximately 13 per cent more efficient than housing built 15 years ago, and more stringent energy efficiency requirements in building codes have contributed to decreased energy use and greenhouse gas (GHG) emissions. However, a survey of residential energy codes across Canada has determined that explicit demands for energy efficiency are currently only present in British Columbia (BC), Manitoba, Ontario and Quebec. The survey evaluated more than 4300 single-detached homes built between 2000 and 2005 using data from the EnerGuide for Houses (EGH) database. House area, volume, airtightness and construction characteristics were reviewed to create archetypes for 8 geographic areas. The survey indicated that in Quebec and the Maritimes, 90 per cent of houses comply with ventilation system requirements of the National Building Code, while compliance in the rest of Canada is much lower. Heat recovery ventilation use is predominant in the Atlantic provinces. Direct-vent or condensing furnaces constitute the majority of installed systems in provinces where natural gas is the primary space heating fuel. Details of Insulation levels for walls, double-glazed windows, and building code insulation standards were also reviewed. It was concluded that if R-2000 levels of energy efficiency were applied, total average energy consumption would be reduced by 36 per cent in Canada. 2 tabs.

Household energy requirement and value patterns

International Nuclear Information System (INIS)

Vringer, Kees; Aalbers, Theo; Blok, Kornelis

2007-01-01

For an effective consumer energy policy, it is important to know why some households require more energy than others. The aim of the study described here was to examine whether there is a relationship between the total household energy requirement, on one hand, and value patterns, the motivation to save energy or the problem perception of climate change, on the other. To examine these relationships, we held a consumer survey among 2304 respondent households. We did not find significant differences in the energy requirement of groups of households with different value patterns, taking into account the differences in the socio-economic situation of households. Only for the 'motivation to save energy' we did find that the least motivated group requires 10 GJ more energy than the average and most motivated groups; this is about 4% of the total household energy requirement. This means that a self-regulating energy policy, solely based on the fact that a strategy of internalising environmental responsibility will not be effective in saving energy. There are indications that a social dilemma is one of the reasons why people's consumption patterns do not conform to their value patterns, problem perception or motivation to save energy

Pengaruh Nisbah Energi-Protein, Nitrogen-Sulfur dan Kalsium-Fosfor Terhadap Produk Metabolisme Rumen dan Kecernaan Substrat

Directory of Open Access Journals (Sweden)

S.N.O. Suwandyastuti

2013-10-01

Full Text Available Influence of the ratio of energy-protein, nitrogen-sulphur, and calsium-phosphor upon rumen metabolism product and digestibility of substrat ABSTRACT. The Rumen microbes are capable to digest the glucosa polymer of plant waste for energy source and can used the Non Protein Nitrogen (NPN for body protein synthesis, if the other precussor (Sulphur, Phospor and Branch Chain of Carbon are available.  To know the effectivity of the utilization of plant waste for energy, an experiment have been conducted by in vitro method, used the Randomized Black Design, four replication, factorial 33.  The factors tested are : (1 three levels of energy : protein (E/P ratio : 4, 5 and 6; (2 three levels of Nitrogen : Sulphur (N/Sratio: 7.5, 10 and 12.5; (3 three levels of Calsium : Phospor (Ca/P ratio : 0.5, 1 and 2. The variables measured are : synthesis of protein microbes (SPM ; production of Volatile Fatty Acid (VFA and Nitrogen Ammonia (N-NH3; the digestibility of substrat. Based on the all variable measured, the experiment can be concluded : (1 the effectivity of the utilization of rice straw will be increased if it used is fortified with 50 percent TDN as energy source (E/P=4, 0.20 percent dry matter of sulphur (N/S=10 and 0.0625 - 0.125 percent dry matter (DM of phospor (Ca/P=1.0 – 2.0; (2 To stimulate the activity of cellulolytic microbes, its need the fortification of sulphur until reach the optimum level (must be investigated.

Coordinated regulation of nitrogen supply mode and initial cell density for energy storage compounds production with economized nitrogen utilization in a marine microalga Isochrysis zhangjiangensis.

Science.gov (United States)

Chi, Lei; Yao, Changhong; Cao, Xupeng; Xue, Song

2016-01-01

Lipids and carbohydrates are main energy storage compounds (ESC) of microalgae under stressed conditions and they are potential feedstock for biofuel production. Yet, the sustainable and commercially successful production of ESC in microalgae needs to consider nitrogen utilization efficiency. Here the impact of different initial cell densities (ICDs) on ESC accumulation in Isochrysis zhangjiangensis under two nitrogen supply modes (an initially equal concentration of nitrogen per-cell in the medium (N1) and an equal total concentration of nitrogen in the culture system (N2)) were investigated. The results demonstrated that the highest ESC yield (1.36gL(-1)) at N1, which included a maximal nitrogen supply in the cultivation system, and the highest ESC content (66.5%) and ESC productivity per mass of nitrogen (3.28gg(-1) (N) day(-1)) at N2, were all obtained under a high ICD of 8.0×10(6)cellsmL(-1). Therefore I. zhangjiangensis qualifies for ESC-enriched biomass production with economized nitrogen utilization. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of dietary protein to energy ratio on growth and nitrogenous ...

African Journals Online (AJOL)

The effect of dietary protein to energy ratio (P:E) on the growth of dusky kob Argyrosomus japonicus was investigated as a first step towards formulating a practical diet for this potential mariculture species in South Africa. The effects of dietary protein and lipid on growth, feed conversion ratio (FCR) and nitrogenous waste ...

Life cycle analysis on fossil energy ratio of algal biodiesel: effects of nitrogen deficiency and oil extraction technology.

Science.gov (United States)

Jian, Hou; Jing, Yang; Peidong, Zhang

2015-01-01

Life cycle assessment (LCA) has been widely used to analyze various pathways of biofuel preparation from "cradle to grave." Effects of nitrogen supply for algae cultivation and technology of algal oil extraction on life cycle fossil energy ratio of biodiesel are assessed in this study. Life cycle fossil energy ratio of Chlorella vulgaris based biodiesel is improved by growing algae under nitrogen-limited conditions, while the life cycle fossil energy ratio of biodiesel production from Phaeodactylum tricornutum grown with nitrogen deprivation decreases. Compared to extraction of oil from dried algae, extraction of lipid from wet algae with subcritical cosolvents achieves a 43.83% improvement in fossil energy ratio of algal biodiesel when oilcake drying is not considered. The outcome for sensitivity analysis indicates that the algal oil conversion rate and energy content of algae are found to have the greatest effects on the LCA results of algal biodiesel production, followed by utilization ratio of algal residue, energy demand for algae drying, capacity of water mixing, and productivity of algae.

Integrating Renewable Energy Requirements Into Building Energy Codes

Energy Technology Data Exchange (ETDEWEB)

Kaufmann, John R.; Hand, James R.; Halverson, Mark A.

2011-07-01

This report evaluates how and when to best integrate renewable energy requirements into building energy codes. The basic goals were to: (1) provide a rough guide of where we’re going and how to get there; (2) identify key issues that need to be considered, including a discussion of various options with pros and cons, to help inform code deliberations; and (3) to help foster alignment among energy code-development organizations. The authors researched current approaches nationally and internationally, conducted a survey of key stakeholders to solicit input on various approaches, and evaluated the key issues related to integration of renewable energy requirements and various options to address those issues. The report concludes with recommendations and a plan to engage stakeholders. This report does not evaluate whether the use of renewable energy should be required on buildings; that question involves a political decision that is beyond the scope of this report.

Factors affecting energy and nitrogen efficiency of dairy cows: A meta-analysis

NARCIS (Netherlands)

Phuong, H.N.; Friggens, N.C.; Boer, de I.J.M.; Schmidely, P.

2013-01-01

A meta-analysis was performed to explore the correlation between energy and nitrogen efficiency of dairy cows, and to study nutritional and animal factors that influence these efficiencies, as well as their relationship. Treatment mean values were extracted from 68 peer-reviewed studies, including

Nitrogen requirements of cassava in selected soils of Thailand

Directory of Open Access Journals (Sweden)

Jakchaiwat Kaweewong

2013-08-01

Full Text Available Cassava (Manihot esculenta is one of the most important export crops in Thailand, yet the nitrogen requirement is unknown and not considered by growers and producers. Cassava requirements for N were determined in field experiments during a period of four years and four sites on the Satuk (Suk, Don Chedi (Dc, Pak Chong (Pc,and Ban Beung (BBg soil series in Lopburi, Supanburi, Nakhon Ratchasima, and Chonburi sites, respectively. The fertilizer treatment structure comprised 0, 62.5, 125, 187.5, 250 and 312.5 kg N ha^(-1 as urea. At each site cassava was harvested at nine months and yield parameters and the minimum datasets were taken. The fertilizer rate which resulted in maximum yield ranged from 187.5 kg N ha^(-1 in Supanburi and Chonburi (fresh weight yield of 47,500 and 30,000 kg ha^(-1 respectively to 250 kg N ha^(-1 in Lopburi and Nakhon Ratchasima (fresh weight yield of 64,100 and 46,700 kg ha^(-1 respectively. Yield appeared to decrease at the higher, 312 kg ha^(-1, at Supanburi and Lopburi, and 250 kg ha^(-1 (Chonburi fertilizer N rates. Net revenue was 70.4 and 72.9 % higher than where no N was appliedLopburi and Nakhon Ratchasima sites. Net revenue at the Supanburi and Chonburi sites were 53.8 and 211.0 % higher than that where no N was applied. This study suggests that at all sites improved cassava production and net revenue could be obtained with the judicious application of higher quantities of N. The results provide needed guidance to nitrogen fertilization of the important industrial crop cassava in Thailand.

Nitrogen nutrition effects on development, growth and nitrogen accumulation of vegetables

NARCIS (Netherlands)

Biemond, H.

1995-01-01

In order to be able to match nitrogen supply and nitrogen requirement of vegetable crops, insight is necessary in the responses to nitrogen of important processes of growth and development. This study focused on effects of amount of nitrogen applied and fractionation of nitrogen supply on

Nitrogen-doped carbon aerogels for electrical energy storage

Science.gov (United States)

Campbell, Patrick; Montalvo, Elizabeth; Baumann, Theodore F.; Biener, Juergen; Merrill, Matthew; Reed, Eric W.; Worsley, Marcus A.

2017-10-03

Disclosed here is a method for making a nitrogen-doped carbon aerogel, comprising: preparing a reaction mixture comprising formaldehyde, at least one nitrogen-containing resorcinol analog, at least one catalyst, and at least one solvent; curing the reaction mixture to produce a wet gel; drying the wet gel to produce a dry gel; and thermally annealing the dry gel to produce the nitrogen-doped carbon aerogel. Also disclosed is a nitrogen-doped carbon aerogel obtained according to the method and a supercapacitor comprising the nitrogen-doped carbon aerogel.

Energy Requirements in Critically Ill Patients

Science.gov (United States)

2018-01-01

During the management of critical illness, optimal nutritional support is an important key for achieving positive clinical outcomes. Compared to healthy people, critically ill patients have higher energy expenditure, thereby their energy requirements and risk of malnutrition being increased. Assessing individual nutritional requirement is essential for a successful nutritional support, including the adequate energy supply. Methods to assess energy requirements include indirect calorimetry (IC) which is considered as a reference method, and the predictive equations which are commonly used due to the difficulty of using IC in certain conditions. In this study, a literature review was conducted on the energy metabolic changes in critically ill patients, and the implications for the estimation of energy requirements in this population. In addition, the issue of optimal caloric goal during nutrition support is discussed, as well as the accuracy of selected resting energy expenditure predictive equations, commonly used in critically ill patients.

Energy Requirements in Critically Ill Patients.

Science.gov (United States)

Ndahimana, Didace; Kim, Eun-Kyung

2018-04-01

During the management of critical illness, optimal nutritional support is an important key for achieving positive clinical outcomes. Compared to healthy people, critically ill patients have higher energy expenditure, thereby their energy requirements and risk of malnutrition being increased. Assessing individual nutritional requirement is essential for a successful nutritional support, including the adequate energy supply. Methods to assess energy requirements include indirect calorimetry (IC) which is considered as a reference method, and the predictive equations which are commonly used due to the difficulty of using IC in certain conditions. In this study, a literature review was conducted on the energy metabolic changes in critically ill patients, and the implications for the estimation of energy requirements in this population. In addition, the issue of optimal caloric goal during nutrition support is discussed, as well as the accuracy of selected resting energy expenditure predictive equations, commonly used in critically ill patients.

Target of rapamycin complex 1 and Tap42-associated phosphatases are required for sensing changes in nitrogen conditions in the yeast Saccharomyces cerevisiae.

Science.gov (United States)

Li, Jinmei; Yan, Gonghong; Liu, Sichi; Jiang, Tong; Zhong, Mingming; Yuan, Wenjie; Chen, Shaoxian; Zheng, Yin; Jiang, Yong; Jiang, Yu

2017-12-01

In yeast target of rapamycin complex 1 (TORC1) and Tap42-associated phosphatases regulate expression of genes involved in nitrogen limitation response and the nitrogen discrimination pathway. However, it remains unclear whether TORC1 and the phosphatases are required for sensing nitrogen conditions. Utilizing temperature sensitive mutants of tor2 and tap42, we examined the role of TORC1 and Tap42 in nuclear entry of Gln3, a key transcription factor in yeast nitrogen metabolism, in response to changes in nitrogen conditions. Our data show that TORC1 is essential for Gln3 nuclear entry upon nitrogen limitation and downshift in nitrogen quality. However, Tap42-associated phosphatases are required only under nitrogen limitation condition. In cells grown in poor nitrogen medium, the nitrogen permease reactivator kinase (Npr1) inhibits TORC1 activity and alters its association with Tap42, rendering Tap42-associated phosphatases unresponsive to nitrogen limitation. These findings demonstrate a direct role for TORC1 and Tap42-associated phosphatases in sensing nitrogen conditions and unveil an Npr1-dependent mechanism that controls TORC1 and the phosphatases in response to changes in nitrogen quality. © 2017 John Wiley & Sons Ltd.

Local electron mean energy profile of positive primary streamer discharge with pin-plate electrodes in oxygen—nitrogen mixtures

International Nuclear Information System (INIS)

Sima Wen-Xia; Peng Qing-Jun; Yang Qing; Yuan Tao; Shi Jian

2013-01-01

Local electron mean energy (LEME) has a direct effect on the rates of collisional ionization of molecules and atoms by electrons. Electron-impact ionization plays an important role and is the main process for the production of charged particles in a primary streamer discharge. Detailed research on the LEME profile in a primary streamer discharge is extremely important for a comprehensive understanding of the local physical mechanism of a streamer. In this study, the LEME profile of the primary streamer discharge in oxygen-nitrogen mixtures with a pin-plate gap of 0.5 cm under an impulse voltage is investigated using a fluid model. The fluid model includes the electron mean energy density equation, as well as continuity equations for electrons and ions and Poisson's electric field equation. The study finds that, except in the initial stage of the primary streamer, the LEME in the primary streamer tip tends to increase as the oxygen-nitrogen mole ratio increases and the pressure decreases. When the primary streamer bridges the gap, the LEME in the primary streamer channel is smaller than the first ionization energies of oxygen and nitrogen. The LEME in the primary streamer channel then decreases as the oxygen-nitrogen mole ratio increases and the pressure increases. The LEME in the primary streamer tip is primarily dependent on the reduced electric field with mole ratios of oxygen-nitrogen given in the oxygen-nitrogen mixtures. (physics of gases, plasmas, and electric discharges)

Electrophoresis examination of strand breaks in plasmid DNA induced by low-energy nitrogen ion irradiation

International Nuclear Information System (INIS)

Zhao Yong; Tan Zheng; Du Yanhua; Qiu Guanying

2003-01-01

To study the effect on plasmid DNA of heavy ion in the energy range of keV where nuclear stopping interaction becomes more important or even predominant, thin film of plasmid pGEM-3Zf(-) DNA was prepared on aluminum surface and irradiated in vacuum ( -3 Pa) by low-energy nitrogen ions with energy of 30 keV (LET=285 keV/μm) at various fluence ranging from 2 x 10 10 to 8.2 x 10 13 ions/cm 2 . DNA strand breaks were analyzed by neutral electrophoresis followed by quantification with image analysis software. Low-energy nitrogen ion irradiation induced single-, double- and multiple double-strand breaks (DSB) and multiple DSB as the dominating form of DNA damages. Moreover, the linear fluence-response relationship at a low fluence range suggests that DSBs are induced predominantly by single ion track. However, strand break production is limited to a short range in the irradiated samples

Understanding Nitrogen Fixation

Energy Technology Data Exchange (ETDEWEB)

Paul J. Chirik

2012-05-25

synthesis of ammonia, NH{sub 3}, from its elements, H{sub 2} and N{sub 2}, via the venerable Haber-Bosch process is one of the most significant technological achievements of the past century. Our research program seeks to discover new transition metal reagents and catalysts to disrupt the strong N {triple_bond} N bond in N{sub 2} and create new, fundamental chemical linkages for the construction of molecules with application as fuels, fertilizers and fine chemicals. With DOE support, our group has discovered a mild method for ammonia synthesis in solution as well as new methods for the construction of nitrogen-carbon bonds directly from N{sub 2}. Ideally these achievements will evolve into more efficient nitrogen fixation schemes that circumvent the high energy demands of industrial ammonia synthesis. Industrially, atmospheric nitrogen enters the synthetic cycle by the well-established Haber-Bosch process whereby N{sub 2} is hydrogenated to ammonia at high temperature and pressure. The commercialization of this reaction represents one of the greatest technological achievements of the 20th century as Haber-Bosch ammonia is responsible for supporting approximately 50% of the world's population and serves as the source of half of the nitrogen in the human body. The extreme reaction conditions required for an economical process have significant energy consequences, consuming 1% of the world's energy supply mostly in the form of pollution-intensive coal. Moreover, industrial H{sub 2} synthesis via the water gas shift reaction and the steam reforming of methane is fossil fuel intensive and produces CO{sub 2} as a byproduct. New synthetic methods that promote this thermodynamically favored transformation ({Delta}G{sup o} = -4.1 kcal/mol) under milder conditions or completely obviate it are therefore desirable. Most nitrogen-containing organic molecules are derived from ammonia (and hence rely on the Haber-Bosch and H{sub 2} synthesis processes) and direct synthesis from

Enzymology of biological nitrogen fixation. Final report, May 1, 1987--April 30, 1996

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-05-01

Biological nitrogen fixation is of central importance in the earth`s nitrogen economy. Fixation of nitrogen is accomplished by a variety of microorganisms, all of them procaryotic. Some operate independently and some function symbiotically or associatively with photosynthesizing plants. Biological nitrogen fixation is accomplished via the reaction: N{sub 2} + 8H{sup +} + 8e{sup {minus}} {yields} 2NH{sub 3} + H{sub 2}. This reaction requires a minimum of 16 ATP under ideal laboratory conditions, so it is obvious that the energy demand of the reaction is very high. When certain nitrogen-fixing organisms are supplied fixed nitrogen (e.g., ammonium) the organisms use the fixed nitrogen and turn off their nitrogenase system, thus conserving energy. When the fixed nitrogen is exhausted, the organism reactivates its nitrogenase. The system is turned off by dinitrogenase reductase ADP-ribosyl transferase (DRAT) and turned back on by dinitrogenase reductase-activating glycohydrolase (DRAG). The authors have investigated the details of how DRAT and DRAG are formed, how they function, and the genetics of their formation and operation.

A diffraction limited nitrogen laser for detector calibration in high energy physics

International Nuclear Information System (INIS)

Hartjes, F.G.

1990-01-01

This thesis consists of two parts. In part I the operation of a pulsed two-stage nitrogen laser is described. In contrast to most other lasers an optical resonator can not be used in a nitrogen laser because of the very short pulse time (∼ 1 ns). Therefore the emitted beam of a simple nitrogen laser has a large divergence. A nitrogen laser with a small beam divergence however can be constructed via the 'Master Oscillator Power Amplifier' principle. Herein a double nitrogen laser system is employed in which both lasers fire simultaneously. The diameter of the laser beam from the first stage (oscillator) is enlarged by a telescope by which the divergence decreases strongly. In a second stage (amplifier) subsequently the weak laser beam is amplified again. The outcoming beam has an elongated diameter which is changed in an approximately round form by a telescope of two cylindrical lenses. The process leading to the formation of population inversion in the nitrogen causing emission of laser ligth is described. The electric circuit, which delivers the high-voltage pulse causing the electric discharge in the laser cavity, is described. The mechanical construction of the laser, in particular with regard to the choices of the materials, is described. Finally, the optical system of the two-stage nitrogen laser is explained. In part II the application of the two-stage nitrogen laser in high-energy physics is treated. Instructions are given about the practical use of the laser: the usual optical system and the ionization profile to be expected in the detector gas. Herein three different kinds of beams are distinguished: the parallel beam, the weakly focussed, and the strongly focussed beam. Some examples are given of the use of the laser: a time very close to the wire, the outlining of the drift wire chambers with a long parallel beam, and the measurement of optical properties of scintillating plastic fibers. (author). 52 refs.; 76 figs.; 4 tabs

A Comparative Density Functional Theory and Density Functional Tight Binding Study of Phases of Nitrogen Including a High Energy Density Material N8

Directory of Open Access Journals (Sweden)

Nicholas Capel

2015-11-01

Full Text Available We present a comparative dispersion-corrected Density Functional Theory (DFT and Density Functional Tight Binding (DFTB-D study of several phases of nitrogen, including the well-known alpha, beta, and gamma phases as well as recently discovered highly energetic phases: covalently bound cubic gauche (cg nitrogen and molecular (vdW-bound N8 crystals. Among several tested parametrizations of N–N interactions for DFTB, we identify only one that is suitable for modeling of all these phases. This work therefore establishes the applicability of DFTB-D to studies of phases, including highly metastable phases, of nitrogen, which will be of great use for modelling of dynamics of reactions involving these phases, which may not be practical with DFT due to large required space and time scales. We also derive a dispersion-corrected DFT (DFT-D setup (atom-centered basis parameters and Grimme dispersion parameters tuned for accurate description simultaneously of several nitrogen allotropes including covalently and vdW-bound crystals and including high-energy phases.

Nitrogen Control in Electric Arc Furnace Steelmaking by DRI (TRP 0009)

Energy Technology Data Exchange (ETDEWEB)

Dr. Gordon A. Irons

2004-03-31

Nitrogen is difficult to remove in electric arc furnace (EAF) steelmaking, requiring the use of more energy in the oxygen steelmaking route to produce low-nitrogen steel. The objective of this work was to determine if the injection of directly reduced iron (DRI) fines into EAFs could reduce the nitrogen content by creating fine carbon monoxide bubbles that rinse nitrogen from the steel. The proposed work included physical and chemical characterization of DRI fines, pilot-scale injection into steel, and mathematical modeling to aid in scale-up of the process. Unfortunately, the pilot-scale injections were unsuccessful, but some full-scale data was obtained. Therefore, the original objectives were met, and presented in the form of recommendations to EAF steelmakers regarding: (1) The best composition and size of DRI fines to use; (2) The amount of DRI fines required to achieve a specific reduction in nitrogen content in the steel; and (3) The injection conditions. This information may be used by steelmakers in techno-economic assessments of the cost of reducing nitrogen with this technology.

Energy requirement of some energy resources

International Nuclear Information System (INIS)

Chapman, P.F.; Hemming, D.F.

1976-01-01

The energy requirements for the sources of energy under examination are expressed as the fraction of total energy consumed in the production of a unit of gross output. Clearly there are vast differences between the energy requirements of these sources of fuels. Using energy analysis it is possible to indicate points of futility where no net energy is produced (i.e. Xsub(f) = 1). For North Sea oil fields using current technology, this appears to occur at a field size of 100,000-200,000 tons of recoverable reserves of oil. For oil shales exploited using above-ground retorting, the outer limit is at a grade of about 5 gal/ton. For uranium ores used to fuel a burner reactor, the cut-off grade was found to be of the order of 20 ppm. However, it should be remembered that at Xsub(f) = 1, there is no net output and the price of the fuel would be infinite. Because of payments to labour and capital, the upper limit of economic viability may well occur at values of Xsub(f) from 0.1 to 0.2. Thus uranium ores of a grade of 100 ppm U 3 O 8 or less may not be ecomically viable using current burner reactors and this in turn implies an upper bound for the total thermal reactor capacity. For oil shales exploited using above-ground retorting and room-and-pillar mining 15-20 gal/ton shale may represent the upper limit of economic viability, depending on the efficiency that can be achieved in a commercial-scale retort

Study on the Requirement of Nitrogen Sources by Scheffersomyces Stipitis NRRL Y-7124 to Produce Ethanol from Xylose Based-media

DEFF Research Database (Denmark)

Mussatto, Solange I.; Carneiro, L. M.; Roberto, I. C.

This study aimed at evaluating the requirement of nitrogen sources by the yeast Scheffersomyces stipitis NRRL Y-7124 to produce ethanol from xylose based-media. Different nitrogen sources were evaluated, which were used to supplement a defined xylose-based medium and also the hemicellulosic hydro...

Energy requirements for racing endurance sled dogs*

OpenAIRE

Loftus, John P.; Yazwinski, Molly; Milizio, Justin G.; Wakshlag, Joseph J.

2014-01-01

Endurance sled dogs have unique dietary energy requirements. At present, there is disparity in the literature regarding energy expenditure and thus energy requirements of these dogs. We sought to further elucidate energy requirements for endurance sled dogs under field conditions. Three sled dog teams completing the 2011 Yukon Quest volunteered to provide diet history. Nutritional content was evaluated and a mock meal was analysed for each team. Race data were obtained from www.yukonquest.com...

Influence of implantation energy on the electrical properties of ultrathin gate oxides grown on nitrogen implanted Si substrates

International Nuclear Information System (INIS)

Kapetanakis, E.; Skarlatos, D.; Tsamis, C.; Normand, P.; Tsoukalas, D.

2003-01-01

Metal-oxide-semiconductor tunnel diodes with gate oxides, in the range of 2.5-3.5 nm, grown either on 25 or 3 keV nitrogen-implanted Si substrates at (0.3 or 1) x10 15 cm -2 dose, respectively, are investigated. The dependence of N 2 + ion implant energy on the electrical quality of the growing oxide layers is studied through capacitance, equivalent parallel conductance, and gate current measurements. Superior electrical characteristics in terms of interface state trap density, leakage current, and breakdown fields are found for oxides obtained through 3 keV nitrogen implants. These findings together with the full absence of any extended defect in the silicon substrate make the low-energy nitrogen implantation technique an attractive option for reproducible low-cost growth of nanometer-thick gate oxides

Fusion Energy Sciences Network Requirements

Energy Technology Data Exchange (ETDEWEB)

Dart, Eli [ESNet, Berkeley, CA (United States); Tierney, Brian [ESNet, Berkeley, CA (United States)

2012-09-26

The Energy Sciences Network (ESnet) is the primary provider of network connectivity for the U.S. Department of Energy Office of Science, the single largest supporter of basic research in the physical sciences in the United States. In support of the Office of Science programs, ESnet regularly updates and refreshes its understanding of the networking requirements of the instruments, facilities, scientists, and science programs that it serves. This focus has helped ESnet to be a highly successful enabler of scientific discovery for over 25 years. In December 2011, ESnet and the Office of Fusion Energy Sciences (FES), of the DOE Office of Science (SC), organized a workshop to characterize the networking requirements of the programs funded by FES. The requirements identified at the workshop are summarized in the Findings section, and are described in more detail in the body of the report.

Investigation of intense XUV emission of nitrogen-puff Z-pinch with small energy input

International Nuclear Information System (INIS)

Raus, J.; Krejci, A.; Piffl, V.

1992-01-01

Light elements like nitrogen or carbon are suggested as optimum working media for small Z-pinches (several kJ energy input). It is shown that such elements can be ionized up to K-shell ionization stages not only in hot-spots, but also in the bulk plasma. The yield of nitrogen K-shell radiation (about 10 J/shot) is therefore substantially higher than that of the conventionally used neon. In addition to pinch physics and radiation dynamics, such radiation could be of interest for applications in the 'water window' spectral region. (author) 1 tab., 4 figs., 8 refs

Carbon and nitrogen assimilation in deep subseafloor microbial cells

OpenAIRE

Morono, Yuki; Terada, Takeshi; Nishizawa, Manabu; Ito, Motoo; Hillion, François; Takahata, Naoto; Sano, Yuji; Inagaki, Fumio

2011-01-01

Remarkable numbers of microbial cells have been observed in global shallow to deep subseafloor sediments. Accumulating evidence indicates that deep and ancient sediments harbor living microbial life, where the flux of nutrients and energy are extremely low. However, their physiology and energy requirements remain largely unknown. We used stable isotope tracer incubation and nanometer-scale secondary ion MS to investigate the dynamics of carbon and nitrogen assimilation activities in individua...

Projections of energy requirements and their implications

International Nuclear Information System (INIS)

Hogroian, P.

1978-01-01

The subject is covered in sections, entitled as shown. Numerical data are indicated in parenthesis. The record of nuclear power forecasting (estimates of the growth of world nuclear power, penetration of the electric power market by nuclear power); brief review of energy forecasting techniques and problems; some views of future world energy demand (estimates of world primary energy requirements); possible allocations of energy resources to needs (allocation of resources (oil, oil from tar sands, shale, natural gas, coal, coal to gasification, hydroelectricity, renewable resources, nuclear) to the world's primary energy needs in the year 2000); observations on the adequacy of energy resources; implications for nuclear energy (postulated growth of world nuclear power, annual fuel cycle requirements of the world, annual uranium requirements of the world). (U.K.)

Nitrogen-doped carbon spheres: A new high-energy-density and long-life pseudo-capacitive electrode material for electrochemical flow capacitor.

Science.gov (United States)

Hou, Shujin; Wang, Miao; Xu, Xingtao; Li, Yandong; Li, Yanjiang; Lu, Ting; Pan, Likun

2017-04-01

One of the most challenging issues in developing electrochemical flow capacitor (EFC) technology is the design and synthesis of active electrode materials with high energy density and long cycle life. However, in practical cases, the energy density and cycle ability obtained currently cannot meet the practical need. In this work, we propose a new active material, nitrogen-doped carbon spheres (NCSs), as flowable electrodes for EFC application. The NCSs were prepared via one-pot hydrothermal synthesis in the presence of resorcinol/formaldehyde as carbon precursors and melamine as nitrogen precursor, followed by carbonization in nitrogen flow at various temperatures. The results of EFC experiments demonstrate that NCSs obtained at 800°C exhibit a high energy density of 13.5Whkg -1 and an excellent cycle ability, indicating the superiority of NCSs for EFC application. Copyright © 2016 Elsevier Inc. All rights reserved.

Nitrogen system for the SSC

International Nuclear Information System (INIS)

McAshan, M.; Thirumaleshwar, M.; Abramovich, S.; Ganni, V.

1992-10-01

The Superconducting Super Collider consists of two parallel magnet rings, each 87,120 m in circumference, constructed in a tunnel 25 m to 74 m below ground level. They are operated at a controlled low helium temperature in order to maintain the magnet windings in the superconducting state. To obtain this condition, the magnet cryostat is designed with a high-quality insulation obtained by a high vacuum chamber, multilayer insulation, and thermal shields at nominal temperatures of 84 K and 20 K. Thermal radiation and the conduction heat load through the supports are intercepted and absorbed by the 84-K shield. Liquid nitrogen provides the refrigeration for these loads. The 84-K shield is anchored to two 63.5-mm stainless-steel tubes. One of the tubes, the ''liquid line,'' serves as a conduit in the distribution system of liquid nitrogen. The other tube, the ''vapor line,'' is used to collect the nitrogen vapor generated in the cooling process and to supply this vapor to,the helium refrigerators for precooling. The vapor line may also be used as a continuous cooler by injecting controlled amounts of liquid nitrogen. The nitrogen system consists of nitrogen supplies; ten nitrogen dewars for the collider and two for the High Energy Booster located on the ground at the main shaft entrances; liquid and vapor transfer lines through the shaft to connect the surface and the tunnel systems; and transfer lines to bypass warm equipment sections of the collider. The nitrogen system is expected to operate at steady state condition except for cooldown, warmup, and system repair, for which transients are expected. During normal operation and standby modes of the collider, temperature, pressure, and mass flow are expected to be constant in all circuits of the nitrogen system. The conceptual design requirements for various flow schemes and the engineering considerations are presented in this report

Variations in the Use of Resources for Food : Land, Nitrogen Fertilizer and Food Nexus

NARCIS (Netherlands)

Jose Ibarrola-Rivas, Maria; Nonhebel, Sanderine

2016-01-01

Future dietary changes will increase the global demand for agricultural resources per person. Food production requires several resources which are interrelated: land, water, nutrients and energy. Other studies have calculated the per capita requirements of only one resource (nitrogen or land). In

Low-energy positron and electron scattering from nitrogen dioxide

International Nuclear Information System (INIS)

Chiari, Luca; Brunger, M J; Zecca, Antonio; García, Gustavo; Blanco, Francisco

2013-01-01

Total cross section (TCS) measurements for positron scattering from nitrogen dioxide (NO 2 ) are presented in the energy range 0.2–40 eV. The TCS, the elastic integral and differential cross sections, and the integral cross section accounting of all the inelastic processes (including positronium formation) have also been computed using the independent atom model with screening corrected additivity rule (IAM-SCAR) for incident energies from 1 to 1000 eV. A qualitative level of agreement is found between the present TCS experiment and theory at the common energies. As no previous measurements or calculations for positron–NO 2  scattering exist in the literature, we also computed the TCS for electron collisions with NO 2  employing the IAM-SCAR method. A comparison of those results to the present positron cross sections and the earlier electron-impact data and calculations is provided. To investigate the role that chemical substitution plays in positron scattering phenomena, we also compare the present positron–NO 2  data with the TCSs measured at the University of Trento for positron scattering from N 2 O and CO 2 . (paper)

Adsorption Energies of Carbon, Nitrogen, and Oxygen Atoms on the Low-temperature Amorphous Water Ice: A Systematic Estimation from Quantum Chemistry Calculations

Science.gov (United States)

Shimonishi, Takashi; Nakatani, Naoki; Furuya, Kenji; Hama, Tetsuya

2018-03-01

We propose a new simple computational model to estimate the adsorption energies of atoms and molecules to low-temperature amorphous water ice, and we present the adsorption energies of carbon (3 P), nitrogen (4 S), and oxygen (3 P) atoms based on quantum chemistry calculations. The adsorption energies were estimated to be 14,100 ± 420 K for carbon, 400 ± 30 K for nitrogen, and 1440 ± 160 K for oxygen. The adsorption energy of oxygen is consistent with experimentally reported values. We found that the binding of a nitrogen atom is purely physisorption, while that of a carbon atom is chemisorption, in which a chemical bond to an O atom of a water molecule is formed. That of an oxygen atom has a dual character, with both physisorption and chemisorption. The chemisorption of atomic carbon also implies the possibility of further chemical reactions to produce molecules bearing a C–O bond, though this may hinder the formation of methane on water ice via sequential hydrogenation of carbon atoms. These properties would have a large impact on the chemical evolution of carbon species in interstellar environments. We also investigated the effects of newly calculated adsorption energies on the chemical compositions of cold dense molecular clouds with the aid of gas-ice astrochemical simulations. We found that abundances of major nitrogen-bearing molecules, such as N2 and NH3, are significantly altered by applying the calculated adsorption energy, because nitrogen atoms can thermally diffuse on surfaces, even at 10 K.

Electron energy-loss spectroscopy characterization and microwave absorption of iron-filled carbon-nitrogen nanotubes

International Nuclear Information System (INIS)

Che Renchao; Liang Chongyun; Shi Honglong; Zhou Xingui; Yang Xinan

2007-01-01

Iron-filled carbon-nitrogen (Fe/CN x ) nanotubes and iron-filled carbon (Fe/C) nanotubes were synthesized at 900 deg. C through a pyrolysis reaction of ferrocene/acetonitrile and ferrocene/xylene, respectively. The differences of structure and composition between the Fe/CN x nanotubes and Fe/C nanotubes were investigated by transmission electron microscopy and electron energy-loss spectroscopy (EELS). It was found that the morphology of Fe/CN x nanotubes is more corrugated than that of the Fe/C nanotubes due to the incorporation of nitrogen. By comparing the Fe L 2,3 electron energy-loss spectra of Fe/CN x nanotubes to those of the Fe/C nanotubes, the electron states at the interface between Fe and the tubular wall of both Fe/CN x nanotubes and Fe/C nanotubes were investigated. At the boundary between Fe and the wall of a CN x nanotube, the additional electrons contributed from the doped 'pyridinic-like' nitrogen might transfer to the empty 3d orbital of the encapsulated iron, therefore leading to an intensity suppression of the iron L 2,3 edge and an intensity enhancement of the carbon K edge. However, such an effect could not be found in Fe/C nanotubes. Microwave absorption properties of both Fe/CN x and Fe/C nanocomposites at 2-18 GHz band were studied

Measurement and Analysis of Rotational Energy of Nitrogen Molecular Beam by REMPI

International Nuclear Information System (INIS)

Mori, H.; Yamaguchi, H.; Kataoka, K.; Sugiyama, N.; Ide, K.; Niimi, T.

2008-01-01

Molecular beams are powerful tools for diagnoses of solid surfaces and gas-surface interaction tests. Unfortunately, there are very few reports about experimental analysis of internal energy distribution (e.g. rotational energy) of molecular beams of diatomic or polyatomic molecules, because measurement of internal energy distribution is very difficult. Spectroscopic measurement techniques based on resonantly enhanced multiphoton ionization (REMPI) is very powerful for measurement in highly rarefied gas flows. In this study, the REMPI method is applied to measurement of rotational energy distribution of nitrogen molecular beams. The REMPI spectrum of the molecular beam indicates the rotational temperature higher than the translational temperature of 7.2 K estimated by assuming isentropic flows. The O and P branches of the REMPI spectrum correspond to the rotational temperature of 30 K, but the S branch of the spectrum deviates from that at 30 K. It seems to be because the non-equilibrium rotational energy distribution of the molecular beam deviates from the Boltzmann distribution.

Investigating Pathways of Nutrient and Energy Flows Through Aquatic Food Webs Using Stable Isotopes of Carbon and Nitrogen

Energy Technology Data Exchange (ETDEWEB)

Hadwen, W. L.; Bunn, S. E. [Australian Rivers Institute, Griffith School of Environment, Griffith University, Nathan Campus, Brisbane, Queensland (Australia)

2013-05-15

Carbon and nitrogen stable isotopes can provide valuable insights into pathways of nutrient and energy flows in aquatic ecosystems. Carbon stable isotopes are principally used to trace pathways of organic matter transfer through aquatic food webs, particularly with regard to identifying the dominant sources of nutrition for aquatic biota. Stable isotopes of carbon have been widely used to answer one of the most pressing questions in aquatic food web ecology - to what degree do in-stream (autochthonous) and riparian (allochthonous) sources of energy fuel riverine food webs? In conjunction with carbon stable isotopes, nitrogen stable isotopes have been used to determine the trophic position of consumers and to identify the number of trophic levels in aquatic food webs. More recently, stable nitrogen isotopes have been recommended as indicators of anthropogenic disturbances. Specifically, agricultural land uses and/or sewage effluent discharge have been shown to significantly increase {delta}{sup 15}N signatures in primary producers and higher order consumers in freshwater, estuarine and marine environments. Together, carbon and nitrogen stable isotopes can be used to examine natural food web functions as well as the degree to which human modifications to catchments and aquatic environments can influence aquatic ecosystem function. (author)

Ceramic packages for liquid-nitrogen operation

International Nuclear Information System (INIS)

Tong, H.M.; Yeh, H.L.; Goldblatt, R.D.

1989-01-01

To evaluate their compatibility for use in a liquid-nitrogen computer, metallized ceramic packages with test chips joined using IBM controlled-collapse solder (Pb-Sn) technology have been cycled between 30 0 C and liquid-nitrogen temperature. Room-temperature electrical resistance measurements were made at regular intervals of cycles to determine whether solder failure accompanied by a significant resistance increase had occurred. For the failed solder joints characterized by the highest thermal shear strain amplitude of 3.3 percent, the authors were able to estimate the number of liquid-nitrogen cycles needed to produce the corresponding failure rate using a room-temperature solder lifetime model. Cross-sectional examination of the failed solder joints using scanning electron microscopy and energy dispersive X-ray analysis indicated solder cracking occurring at the solder-ceramic interface. Chip pull tests on cycled packages yielded strengths far exceeding the minimal requirement. Mechanisms involving the formation of intermetallics were proposed to account for the observed solder fracture modes after liquid-nitrogen cycling and after chip pull. Furthermore, scanning electron microscopic examination of pulled chips in cycled packages showed no apparent sign of cracking in quartz and polyimide for chip insulation

Environmental Systems Simulations for Carbon, Energy, Nitrogen, Water, and Watersheds: Design Principles and Pilot Testing

NARCIS (Netherlands)

Lant, C.; Pérez Lapena, B.; Xiong, W.; Kraft, S.; Kowalchuk, R.; Blair, M.

2016-01-01

Guided by the Next Generation Science Standards and elements of problem-based learning, four human-environment systems simulations are described in brief—carbon, energy, water, and watershed—and a fifth simulation on nitrogen is described in more depth. These science, technology, engineering, and

Effects of irradiation with low-energy nitrogen ion injection on root tip cells of broad bean

International Nuclear Information System (INIS)

Huang Yaqin; Li Jinzhe; Huang Qunce

2012-01-01

In order to study the cytogenetic effects of low-energy nitrogen ion irradiation, broad bean seed embryo was irradiated by different doses of nitrogen ions. Micronucleus rate, mitotic index and chromosome aberration in root-tip cells were analyzed. The results showed that the injection of ions inhibited mitosis of root tip cells, interfered the normal process of mitosis, caused aberrations of chromosome structure, behavior and number. The frequency of micronucleus and chromosomal aberrations increased with the increasing radiation dosage, while mitotic index decreased. (authors)

Measurement of omega, the energy required to create an ion pair, for 150-MeV protons in nitrogen and argon

International Nuclear Information System (INIS)

Petti, P.L.

1985-01-01

The purpose of this thesis is to provide a 1% measurement of omega, the energy required to produce an ion pair, for 150 MeV protons in various gases. Such a measurement should improve the accuracy of proton ionization chamber dosimetry at the Harvard Cyclotron Laboratory. Currently, no measurements of omega exist in the energy range of 30 to 150 MeV, and present ionization chamber dosimetry at the Cyclotron relies on average values of measurements at lower and higher energies (i.e. for E < 3 MeV and E = 340 MeV). Contrary to theoretical expectations, these low and high energy data differ by as much as 9% in some gases. The results of this investigation demonstrate that the existing high energy data is probably in error, and current proton ionization chamber dosimetry underestimates omega, and hence the proton dose, by 5%

Prussian blue-nitrogen-doped graphene nanocomposite as hybrid electrode for energy storage applications

International Nuclear Information System (INIS)

Sookhakian, M.; Basirun, W.J.; Teridi, Mohd Asri Mat; Mahmoudian, M.R.; Azarang, Majid; Zalnezhad, Erfan; Yoon, G.H.; Alias, Y.

2017-01-01

Highlights: • Novel and inexpensive Prussian blue-N-graphene composite for hybrid battery- supercapacitor. • Prussian blue leads to a significant increase of the capacity. • Prussian blue leads to enhancement of cycling stability of N-graphene. - Abstract: Water-soluble Prussian blue nanoparticles (PB NPs) supported on nitrogen-doped graphene (N-graphene) with high dispersion was fabricated for high performance energy storage hybrid electrodes. An efficient loading of the PB NPs and nitrogen doping of graphene were achieved. The structure and morphology of the composite was determined by X-ray diffraction, transmission electron microscopy, Raman spectrometry and X-ray photoelectron spectrometry. The energy storage performance was assessed by cyclic voltammetry and galvanostatic charge/discharge techniques. The nanocomposite was fabricated as a hybrid battery-supercapacitor electrode and exhibited excellent performance with the highest capacity of 660 C g −1 at 1 A g −1 , which was higher than pure PB NPs and N-graphene electrodes. Moreover, the synergistic effect of N-graphene and the PB NPs prevented the N-graphene from shrinking and swelling and increased the cycle stability to 84.7% retention after 1500 cycles at 6 A g −1 , compared to the pure N-graphene.

Terrestrial nitrogen cycles: Some unanswered questions

Science.gov (United States)

Vitousek, P.

1984-01-01

Nitrogen is generally considered to be the element which most often limits the growth of plants in both natural and agricultural ecosystems. It regulates plant growth because photosynthetic rates are strongly dependent on the concentration of nitrogen in leaves, and because relatively large mounts of protein are required for cell division and growth. Yet nitrogen is abundant in the biosphere - the well-mixed pool in the atmosphere is considered inexhaustible compared to biotic demand, and the amount of already fixed organic nitrogen in soils far exceeds annual plant uptake in terrestrial ecosystems. In regions where natural vegetation is not nitrogen limited, continuous cultivation induces nitrogen deficiency. Nitrogen loss from cultivated lands is more rapid than that of other elements, and nitrogen fertilization is generally required to maintain crop yield under any continuous system. The pervasiveness of nitrogen deficiency in many natural and most managed sites is discussed.

Nitrogen-system safety study: Portsmouth Gaseous Diffusion Plant

International Nuclear Information System (INIS)

1982-07-01

The Department of Energy has primary responsibility for the safety of operations at DOE-owned nuclear facilities. The guidelines for the analysis of credible accidents are outlined in DOE Order 5481.1. DOE has requested that existing plant facilities and operations be reviewed for potential safety problems not covered by standard industrial safety procedures. This review is being conducted by investigating individual facilities and documenting the results in Safety Study Reports which will be compiled to form the Existing Plant Final Safety Analysis Report which is scheduled for completion in September, 1984. This Safety Study documents the review of the Plant Nitrogen System facilities and operations and consists of Section 4.0, Facility and Process Description, and Section 5.0, Accident Analysis, of the Final Safety Analysis Report format. The existing nitrogen system consists of a Superior Air Products Company Type D Nitrogen Plant, nitrogen storage facilities, vaporization facilities and a distribution system. The system is designed to generate and distribute nitrogen gas used in the cascade for seal feed, buffer systems, and for servicing equipment when exceptionally low dew points are required. Gaseous nitrogen is also distributed to various process auxiliary buildings. The average usage is approximately 130,000 standard cubic feet per day

Energy balance and greenhouse gas emissions of dryland camelina as influenced by tillage and nitrogen

International Nuclear Information System (INIS)

Keshavarz-Afshar, Reza; Mohammed, Yesuf Assen; Chen, Chengci

2015-01-01

Despite the great potential of camelina (Camelina sativa L. Crantz) as a promising biofuel feedstock, in-farm energy flow of the crop and its associated environmental impacts has not received sufficient attention from researchers. In order to assess net energy gain and to identify energy saving and environmental friendly production operations, a two year study was conducted at central Montana. We investigated the effects of tillage method (CT (conventional tillage) vs. NT (no-tillage)) and N (nitrogen) fertilizer rate (0, 45, 90 kg N ha −1 ) on energy balance and GHG (greenhouse gas emission) of dryland camelina production. Results indicated that energy input and GHG emission were 5 and 8% lower in NT than in CT. Application of 45 and 90 kg N ha −1 increased camelina energy input by 186 and 365%, while increased energy output by only 21 and 64%, respectively. There was no significant difference in net energy gain in response to N fertilization, but lower energy efficiency in response to higher N inputs. Averaged across tillage systems, the GHG emission was 32.0 kg C eq ha −1 with 0 N applied, and the GHG emission increased by 206 and 389% when 45 and 90 kg N ha −1 was applied. Overall, N fertilizer had the biggest share in total energy input. Averaged over all experimental treatments, 14,945 MJ ha −1 net energy was obtained from camelina crop in this study which shows the potential of this crop as a bioenergy feedstock. Our result showed that implementation of NT is strongly recommendable for camelina production in this region. Moreover, improvement of N use efficiency has the highest priority to improve energy performance and reduce GHG emissions in camelina production. - Highlights: • Camelina produced 14,945 MJ ha −1 of net energy in this study. • No tillage operation reduced 5% energy input and 8% greenhouse gas emission. • Nitrogen fertilizer was the most energy-intensive input in camelina production.

Constraint-Based Modeling Highlights Cell Energy, Redox Status and α-Ketoglutarate Availability as Metabolic Drivers for Anthocyanin Accumulation in Grape Cells Under Nitrogen Limitation

Directory of Open Access Journals (Sweden)

Eric Soubeyrand

2018-05-01

Full Text Available Anthocyanin biosynthesis is regulated by environmental factors (such as light, temperature, and water availability and nutrient status (such as carbon, nitrogen, and phosphate nutrition. Previous reports show that low nitrogen availability strongly enhances anthocyanin accumulation in non carbon-limited plant organs or cell suspensions. It has been hypothesized that high carbon-to-nitrogen ratio would lead to an energy excess in plant cells, and that an increase in flavonoid pathway metabolic fluxes would act as an “energy escape valve,” helping plant cells to cope with energy and carbon excess. However, this hypothesis has never been tested directly. To this end, we used the grapevine Vitis vinifera L. cultivar Gamay Teinturier (syn. Gamay Freaux or Freaux Tintorier, VIVC #4382 cell suspension line as a model system to study the regulation of anthocyanin accumulation in response to nitrogen supply. The cells were sub-cultured in the presence of either control (25 mM or low (5 mM nitrate concentration. Targeted metabolomics and enzyme activity determinations were used to parametrize a constraint-based model describing both the central carbon and nitrogen metabolisms and the flavonoid (phenylpropanoid pathway connected by the energy (ATP and reducing power equivalents (NADPH and NADH cofactors. The flux analysis (2 flux maps generated, for control and low nitrogen in culture medium clearly showed that in low nitrogen-fed cells all the metabolic fluxes of central metabolism were decreased, whereas fluxes that consume energy and reducing power, were either increased (upper part of glycolysis, shikimate, and flavonoid pathway or maintained (pentose phosphate pathway. Also, fluxes of flavanone 3β-hydroxylase, flavonol synthase, and anthocyanidin synthase were strongly increased, advocating for a regulation of the flavonoid pathway by alpha-ketoglutarate levels. These results strongly support the hypothesis of anthocyanin biosynthesis acting as

Nutrient and energy recovery from urine

NARCIS (Netherlands)

Kuntke, P.

2013-01-01

Keywords: urine, urine treatment, nutrient recovery, microbial fuel cells, energy production from urine, membrane capacitive deionization.

In conventional wastewater treatment plants large amounts of energy are required for the removal and recovery of nutrients (i.e. nitrogen and

Development and supply of the world energy requirement

International Nuclear Information System (INIS)

Schulz, E.

1981-01-01

Recently published research reveals that the world energy requirement can and must grow more slowly than previously anticipated. In order to supply developing nations with the energy necessary for the expansion of their economies, energy saving and oil substitution assume greater significance in the industrialised countries such as the Federal Republic. Future fulfillment of the world energy requirement will be characterised by escalating costs for supply, especially for the current main energy carrier oil, on the one hand and by increased use of coal and nuclear energy as well unconventional fossils such as regenerative energies on the other. Nuclear energy and thus the electricity economy must play a key function in the future energy supply of industrial nations such as Federal Germany. Nuclear energy enables, both directly and indirectly, the substitution of oil in the heat market, supplies the process heat required for coal production and, due to the ease of storage or uranium, provides a hedge against fluctuations on the world energy market. (orig.) [de

JV Task-121 Electrochemical Synthesis of Nitrogen Fertilizers

Energy Technology Data Exchange (ETDEWEB)

Junhua Jiang; Ted Aulich

2008-11-30

An electrolytic renewable nitrogen fertilizer process that utilizes wind-generated electricity, N{sub 2} extracted from air, and syngas produced via the gasification of biomass to produce nitrogen fertilizer ammonia was developed at the University of North Dakota Energy & Environmental Research Center. This novel process provides an important way to directly utilize biosyngas generated mainly via the biomass gasification in place of the high-purity hydrogen which is required for Haber Bosch-based production of the fertilizer for the production of the widely used nitrogen fertilizers. Our preliminary economic projection shows that the economic competitiveness of the electrochemical nitrogen fertilizer process strongly depends upon the cost of hydrogen gas and the cost of electricity. It is therefore expected the cost of nitrogen fertilizer production could be considerably decreased owing to the direct use of cost-effective 'hydrogen-equivalent' biosyngas compared to the high-purity hydrogen. The technical feasibility of the electrolytic process has been proven via studying ammonia production using humidified carbon monoxide as the hydrogen-equivalent vs. the high-purity hydrogen. Process optimization efforts have been focused on the development of catalysts for ammonia formation, electrolytic membrane systems, and membrane-electrode assemblies. The status of the electrochemical ammonia process is characterized by a current efficiency of 43% using humidified carbon monoxide as a feedstock to the anode chamber and a current efficiency of 56% using high-purity hydrogen as the anode gas feedstock. Further optimization of the electrolytic process for higher current efficiency and decreased energy consumption is ongoing at the EERC.

Formation of simple nitrogen hydrides NH and NH2 at cryogenic temperatures through N + NH3→ NH + NH2 reaction: dark cloud chemistry of nitrogen.

Science.gov (United States)

Nourry, Sendres; Krim, Lahouari

2016-07-21

Although NH3 molecules interacting with ground state nitrogen atoms N((4)S) seem not to be a very reactive system without providing additional energy to initiate the chemical process, we show through this study that, in the solid phase, at very low temperature, NH3 + N((4)S) reaction leads to the formation of the amidogen radical NH2. Such a dissociation reaction previously thought to occur exclusively through UV photon or energetic particle irradiation is in this work readily occurring just by stimulating the mobility of N((4)S)-atoms in the 3-10 K temperature range in the solid sample. The N((4)S)-N((4)S) recombination may be the source of metastable molecular nitrogen N2(A), a reactive species which might trigger the NH3 dissociation or react with ground state nitrogen atoms N((4)S) to form excited nitrogen atoms N((4)P/(2)D) through energy transfer processes. Based on our obtained results, it is possible to propose reaction pathways to explain the NH2 radical formation which is the first step in the activation of stable species such as NH3, a chemical induction process that, in addition to playing an important role in the origin of molecular complexity in interstellar space, is known to require external energy supplies to occur in the gas phase.

Simulated Nitrogen Deposition has Minor Effects on Ecosystem Pools and Fluxes of Energy, Elements, and Biochemicals in a Northern Hardwoods Forest

Science.gov (United States)

Talhelm, A. F.; Pregitzer, K. S.; Burton, A. J.; Xia, M.; Zak, D. R.

2017-12-01

The elemental and biochemical composition of plant tissues is an important influence on primary productivity, decomposition, and other aspects of biogeochemistry. Human activity has greatly altered biogeochemical cycles in ecosystems downwind of industrialized regions through atmospheric nitrogen deposition, but most research on these effects focuses on individual elements or steps in biogeochemical cycles. Here, we quantified pools and fluxes of biomass, the four major organic elements (carbon, oxygen, hydrogen, nitrogen), four biochemical fractions (lignin, structural carbohydrates, cell walls, and soluble material), and energy in a mature northern hardwoods forest in Michigan. We sampled the organic and mineral soil, fine and coarse roots, leaf litter, green leaves, and wood for chemical analyses. We then combined these data with previously published and archival information on pools and fluxes within this forest, which included replicated plots receiving either ambient deposition or simulated nitrogen deposition (3 g N m-2 yr-1 for 18 years). Live wood was the largest pool of energy and all elements and biochemical fractions. However, the production of wood, leaf litter, and fine roots represented similar fluxes of carbon, hydrogen, oxygen, cell wall material, and energy, while nitrogen fluxes were dominated by leaf litter and fine roots. Notably, the flux of lignin via fine roots was 70% higher than any other flux. Experimental nitrogen deposition had relatively few significant effects, increasing foliar nitrogen, increasing the concentration of lignin in the soil organic horizon and decreasing pools of all elements and biochemical fractions in the soil organic horizon except nitrogen, lignin, and structural carbohydrates. Overall, we found that differences in tissue chemistry concentrations were important determinants of ecosystem-level pools and fluxes, but that nitrogen deposition had little effect on concentrations, pools, or fluxes in this mature forest

Maintenance Energy Requirements of Double-Muscled Belgian Blue Beef Cows

Directory of Open Access Journals (Sweden)

Leo O. Fiems

2015-02-01

Full Text Available Sixty non-pregnant, non-lactating double-muscled Belgian Blue (DMBB cows were used to estimate the energy required to maintain body weight (BW. They were fed one of three energy levels for 112 or 140 days, corresponding to approximately 100%, 80% or 70% of their total energy requirements. The relationship between daily energy intake and BW and daily BW change was developed using regression analysis. Maintenance energy requirements were estimated from the regression equation by setting BW gain to zero. Metabolizable and net energy for maintenance amounted to 0.569 ± 0.001 and 0.332 ± 0.001 MJ per kg BW0.75/d, respectively. Maintenance energy requirements were not dependent on energy level (p > 0.10. Parity affected maintenance energy requirements (p < 0.001, although the small numerical differences between parities may hardly be nutritionally relevant. Maintenance energy requirements of DMBB beef cows were close to the mean energy requirements of other beef genotypes reported in the literature.

Maintenance Energy Requirements of Double-Muscled Belgian Blue Beef Cows.

Science.gov (United States)

Fiems, Leo O; De Boever, Johan L; Vanacker, José M; De Campeneere, Sam

2015-02-13

Sixty non-pregnant, non-lactating double-muscled Belgian Blue (DMBB) cows were used to estimate the energy required to maintain body weight (BW). They were fed one of three energy levels for 112 or 140 days, corresponding to approximately 100%, 80% or 70% of their total energy requirements. The relationship between daily energy intake and BW and daily BW change was developed using regression analysis. Maintenance energy requirements were estimated from the regression equation by setting BW gain to zero. Metabolizable and net energy for maintenance amounted to 0.569 ± 0.001 and 0.332 ± 0.001 MJ per kg BW(0.75)/d, respectively. Maintenance energy requirements were not dependent on energy level (p > 0.10). Parity affected maintenance energy requirements (p < 0.001), although the small numerical differences between parities may hardly be nutritionally relevant. Maintenance energy requirements of DMBB beef cows were close to the mean energy requirements of other beef genotypes reported in the literature.

Maintenance Energy Requirements of Double-Muscled Belgian Blue Beef Cows

Science.gov (United States)

Fiems, Leo O.; De Boever, Johan L.; Vanacker, José M.; De Campeneere, Sam

2015-01-01

Simple Summary Double-muscled Belgian Blue animals are extremely lean, characterized by a deviant muscle fiber type with more fast-glycolytic fibers, compared to non-double-muscled animals. This fiber type may result in lower maintenance energy requirements. On the other hand, lean meat animals mostly have a higher rate of protein turnover, which requires more energy for maintenance. Therefore, maintenance requirements of Belgian Blue cows were investigated based on a zero body weight gain. This technique showed that maintenance energy requirements of double-muscled Belgian Blue beef cows were close to the mean requirements of cows of other beef genotypes. Abstract Sixty non-pregnant, non-lactating double-muscled Belgian Blue (DMBB) cows were used to estimate the energy required to maintain body weight (BW). They were fed one of three energy levels for 112 or 140 days, corresponding to approximately 100%, 80% or 70% of their total energy requirements. The relationship between daily energy intake and BW and daily BW change was developed using regression analysis. Maintenance energy requirements were estimated from the regression equation by setting BW gain to zero. Metabolizable and net energy for maintenance amounted to 0.569 ± 0.001 and 0.332 ± 0.001 MJ per kg BW0.75/d, respectively. Maintenance energy requirements were not dependent on energy level (p > 0.10). Parity affected maintenance energy requirements (p < 0.001), although the small numerical differences between parities may hardly be nutritionally relevant. Maintenance energy requirements of DMBB beef cows were close to the mean energy requirements of other beef genotypes reported in the literature. PMID:26479139

Projecting India's energy requirements for policy formulation

International Nuclear Information System (INIS)

Parikh, Kirit S.; Karandikar, Vivek; Rana, Ashish; Dani, Prasanna

2009-01-01

Energy policy has to have a long-term perspective. To formulate it one needs to know the contours of energy requirements and options. Different approaches have been followed in literature, each with their own problems. A top down econometric approach provides little guidance on policies, while a bottom up approval requires too much knowledge and too many assumptions. Using top-down econometric approach for aggregate overall benchmarking and a detailed activity analysis model, Integrated Energy System Model, for a few large sectors, provides a unique combination for easing the difficulties of policy formulation. The model is described in this paper. Eleven alternate scenarios are built, designed to map out extreme points of feasible options. Results show that even after employing all domestic energy resource to their full potential, there will be a continued rise of fossil fuel use, continued importance of coal, and continued rise of import dependence. Energy efficiency emerges as a major option with a potential to reduce energy requirement by as much as 17%. Scenario results point towards pushing for development of alternative sources. (author)

Ste12/Fab1 phosphatidylinositol-3-phosphate 5-kinase is required for nitrogen-regulated mitotic commitment and cell size control.

Directory of Open Access Journals (Sweden)

David Cobley

Full Text Available Tight coupling of cell growth and cell cycle progression enable cells to adjust their rate of division, and therefore size, to the demands of proliferation in varying nutritional environments. Nutrient stress promotes inhibition of Target Of Rapamycin Complex 1 (TORC1 activity. In fission yeast, reduced TORC1 activity advances mitotic onset and switches growth to a sustained proliferation at reduced cell size. A screen for mutants, that failed to advance mitosis upon nitrogen stress, identified a mutant in the PIKFYVE 1-phosphatidylinositol-3-phosphate 5-kinase fission yeast homolog Ste12. Ste12PIKFYVE deficient mutants were unable to advance the cell cycle to reduce cell size after a nitrogen downshift to poor nitrogen (proline growth conditions. While it is well established that PI(3,5P2 signalling is required for autophagy and that Ste12PIKFYVE mutants have enlarged vacuoles (yeast lysosomes, neither a block to autophagy or mutants that independently have enlarged vacuoles had any impact upon nitrogen control of mitotic commitment. The addition of rapamycin to Ste12PIKFYVE deficient mutants reduced cell size at division to suggest that Ste12PIKFYVE possibly functions upstream of TORC1. ste12 mutants display increased Torin1 (TOR inhibitor sensitivity. However, no major impact on TORC1 or TORC2 activity was observed in the ste12 deficient mutants. In summary, Ste12PIKFYVE is required for nitrogen-stress mediated advancement of mitosis to reduce cell size at division.

Nitrogen and Oxygen Isotopic Studies of the Marine Nitrogen Cycle.

Science.gov (United States)

Casciotti, Karen L

2016-01-01

The marine nitrogen cycle is a complex web of microbially mediated reactions that control the inventory, distribution, and speciation of nitrogen in the marine environment. Because nitrogen is a major nutrient that is required by all life, its availability can control biological productivity and ecosystem structure in both surface and deep-ocean communities. Stable isotopes of nitrogen and oxygen in nitrate and nitrite have provided new insights into the rates and distributions of marine nitrogen cycle processes, especially when analyzed in combination with numerical simulations of ocean circulation and biogeochemistry. This review highlights the insights gained from dual-isotope studies applied at regional to global scales and their incorporation into oceanic biogeochemical models. These studies represent significant new advances in the use of isotopic measurements to understand the modern nitrogen cycle, with implications for the study of past ocean productivity, oxygenation, and nutrient status.

FY1995 studies on saving energy by use of nitrogen- fixing bacteria; 1995 nendo chisso koteikin no katsuyo ni yoru sho energy no kenkyu

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

To save energy by improving the ability of nitrogen-fixing bacteria (Kebsiella oxytoca, Azospirillum lipoferum and Sphingomonas paucimobilis) in the rhizosphere of rice, by means of genetic analysis and engineering of the nif genes. Analysis and improvement of the nif genes were performed in 3 species of nitrogen-fixing bacteria in the rhizoshere of rice. (1) In an facultative anaerobe, K. oxytoca, the repressor gene, nifL was destroyed, and the activator gene, nifA was fortified, to attain a novel mutant strain R16, which fixes nitrogen even in the presence of NH{sub 4}{sup +}. (2) In a microaerophilic nitrogen fixer, A. lipoferum, the regulatory genes draT and draG were cloned and analysed, and an improved strain TA1 was obtained by introduction of K. oxytoca nifA gene. (3) In an aerobic nitrogen-fixer S. paucimobilis, the nifA gene was cloned and sequenced, and the activity was expressed in E. coil to show that the product activates the nif promoters of Azospirillurn and Klebsiella. (4) The improved strains K. oxytoca R16 and A. lipoferun TA1 were inoculated to rice plant cultured in a pot without addition of nitrogen source. The inoculated plant showed twice as much dry weight as the noninoculated plant, showing that the improved strains are effective to stimulate the growth of rice. (NEDO)

Breeding food and forge legumes for enhancement of nitrogen fixation: a review

International Nuclear Information System (INIS)

Ali, A.; Hussain, S.; Qamar, I.A.; Khan, B.R.

2000-01-01

Nitrogen fixation in legume - root nodules requires the functioning of genes present in the Rhizobia that induce nodule-formation. The plant produces the nodules and the energy required for respiration. Genes in both Rhizobium and the plant are responsible for the efficient use of photosynthesis for N/sub 2/ fixation and assimilation of nitrogen. Genes from Rhizobium and legume hosts that are involved in the symbiosis are being identified, isolated and cloned, to facilitate the manipulation of either partner. The amounts of nitrogen fixed by grain-legumes vary appreciably, between and within, species and are also influenced by environment. With few exceptions, most legumes fix insufficient N/sub 2/ to support substantial seed-yields. Deficits between required N and the combined amounts provide by soil and fertilizer help in estimating the improvements in N/sub 2/ fixation which is possible through breeding. Since the symbiosis is a complex process, heritability of traits is weak, and most methods which estimate fixation are destructive, a breeding method that allows selection of replicated families rather than single plants is preferred. (author)

Energy requirements for growth in the Yorkshire terrier.

Science.gov (United States)

Alexander, Janet E; Colyer, Alison; Morris, Penelope J

2017-01-01

The 2006 National Research Council (NRC) equation calculating puppy energy requirements does not account for reported breed differences in growth pattern. Energy requirements of toy breed puppies are unknown and it is unclear whether feeding guidelines should differ between breeds. Energy requirements of Yorkshire terrier (YT) puppies were observed over their first year of life and compared with those predicted by the NRC and those previously observed in large (Labrador retriever) and medium (miniature Schnauzer; MS) breed puppies. Twenty-two puppies (from eight litters) were offered complete and balanced diets to maintain ideal body condition score (BCS). Energy intake, body weight and BCS were recorded from 10 to 52 weeks of age. Every 12 weeks, health was monitored by veterinary examination, routine haematology and plasma biochemistry. Puppies remained clinically healthy with normal skeletal development throughout. After analysis by linear mixed models it was observed that the NRC equation overestimates YT energy requirements between 10 and 20 weeks of age by up to 324·3 (95 % CI 390·4, 258·2) kJ/kg 0·75 . Energy intake was lower ( P  < 0·05) in YT than Labradors until 29 weeks by up to 376·6 (95 % CI 477·4, 275·3) kJ/kg 0·75 and lower than MS between 16 and 25 weeks by up to 216·3 (95 % CI 313·0, 119·7) kJ/kg 0·75 ( P  < 0·05). Data indicate differences in toy, medium and large breed energy requirements for growth. The NRC equation for puppy energy requirements overestimated the requirements of this YT population, suggesting the need for breed-specific feeding guides for growth to avoid overfeeding.

Energy requirements, protein-energy metabolism and balance, and carbohydrates in preterm infants.

Science.gov (United States)

Hay, William W; Brown, Laura D; Denne, Scott C

2014-01-01

Energy is necessary for all vital functions of the body at molecular, cellular, organ, and systemic levels. Preterm infants have minimum energy requirements for basal metabolism and growth, but also have requirements for unique physiology and metabolism that influence energy expenditure. These include body size, postnatal age, physical activity, dietary intake, environmental temperatures, energy losses in the stool and urine, and clinical conditions and diseases, as well as changes in body composition. Both energy and protein are necessary to produce normal rates of growth. Carbohydrates (primarily glucose) are principle sources of energy for the brain and heart until lipid oxidation develops over several days to weeks after birth. A higher protein/energy ratio is necessary in most preterm infants to approximate normal intrauterine growth rates. Lean tissue is predominantly produced during early gestation, which continues through to term. During later gestation, fat accretion in adipose tissue adds increasingly large caloric requirements to the lean tissue growth. Once protein intake is sufficient to promote net lean body accretion, additional energy primarily produces more body fat, which increases almost linearly at energy intakes >80-90 kcal/kg/day in normal, healthy preterm infants. Rapid gains in adiposity have the potential to produce later life obesity, an increasingly recognized risk of excessive energy intake. In addition to fundamental requirements for glucose, protein, and fat, a variety of non-glucose carbohydrates found in human milk may have important roles in promoting growth and development, as well as production of a gut microbiome that could protect against necrotizing enterocolitis. © 2014 S. Karger AG, Basel.

Protein requirements of finishing paca (Cuniculus paca).

Science.gov (United States)

Nogueira-Filho, Sérgio Luiz Gama; Bastos, Ivanise da Hora; Mendes, Alcester; Nogueira, Selene Siqueira da Cunha

2016-06-01

We conducted a nitrogen balance digestion trial to determine the crude protein requirements of paca (Cuniculus paca) during the last growth phase. In a 4 × 4 Latin square design, four young captive male pacas, aged 5 months, were fed four isoenergetic diets containing four different levels of nitrogen (N) (11.3, 16.6, 21.4, and 26.6 g N/kg of dry matter). After 15 days of adaptation, we collected all feces and urine for five consecutive days. By regression analysis between N intake and N in feces and urine, the metabolic fecal nitrogen (MFN = 4.2 g/kg of dry matter intake) and daily endogenous urinary N (EUN = 91.6 mg/kg(0.75)) were determined. Likewise, by regression analyses between nitrogen intake and nitrogen retention [NR = N intake-(fecal N + urine N)], we estimated the daily requirement of 280.5 mg N/kg(0.75). Therefore, a minimum of 55 g crude protein per kilogram dry matter and 13 MJ/kg of digestible energy are required by finishing paca on unrestricted diets. Such values are similar to those of other wild frugivores and below those of growing rabbits. The data confirm that farmers overfeed protein, and similar growth can be more economically achieved on lower protein diets.

Favoring the unfavored: Selective electrochemical nitrogen fixation using a reticular chemistry approach.

Science.gov (United States)

Lee, Hiang Kwee; Koh, Charlynn Sher Lin; Lee, Yih Hong; Liu, Chong; Phang, In Yee; Han, Xuemei; Tsung, Chia-Kuang; Ling, Xing Yi

2018-03-01

Electrochemical nitrogen-to-ammonia fixation is emerging as a sustainable strategy to tackle the hydrogen- and energy-intensive operations by Haber-Bosch process for ammonia production. However, current electrochemical nitrogen reduction reaction (NRR) progress is impeded by overwhelming competition from the hydrogen evolution reaction (HER) across all traditional NRR catalysts and the requirement for elevated temperature/pressure. We achieve both excellent NRR selectivity (~90%) and a significant boost to Faradic efficiency by 10 percentage points even at ambient operations by coating a superhydrophobic metal-organic framework (MOF) layer over the NRR electrocatalyst. Our reticular chemistry approach exploits MOF's water-repelling and molecular-concentrating effects to overcome HER-imposed bottlenecks, uncovering the unprecedented electrochemical features of NRR critical for future theoretical studies. By favoring the originally unfavored NRR, we envisage our electrocatalytic design as a starting point for high-performance nitrogen-to-ammonia electroconversion directly from water vapor-abundant air to address increasing global demand of ammonia in (bio)chemical and energy industries.

The energy requirement of holidays and household reduction options

International Nuclear Information System (INIS)

Van den Berg, M.; Vringer, K.

1999-12-01

Like all consumer products and services, holidays require energy. The aim of this study is to give insight to the energy consumption for holidays of Dutch households and to suggest options to reduce this energy demand. To examine the energy consumption for holidays, nine holiday packages are composed, each representing a large group of Dutch vacationers. The packages describe the destination, means of transport, duration, accommodation and number of vacationers. The average energy requirement for the accommodation and transport for long summer holidays is 12.5 GJ per Dutch household, excluding the energy requirement for food and activities. About 10% of the Dutch households, the ones that travel by plane to their holiday destination, consume 70% of the total amount of energy all households require for holiday purposes. This is mainly due to the distance travelled, rather than to the chosen means of transport. If the travelled distances will be reduced by 50% and all nights are spent in a tent, the average household energy requirement would be 6.1 GJ, a reduction of more than 50%. 36 refs

Sensitivity of nitrogen dioxide concentrations to oxides of nitrogen controls in the United Kingdom

International Nuclear Information System (INIS)

Dixon, J.

2001-01-01

There is a possibility of further controls on emissions to the atmosphere of nitrogen dioxides to meet air quality objectives in the UK. Data in the National Air Quality Archive were used to calculate the likely sensitivity of hourly concentrations of nitrogen dioxide in ambient urban air to changes in the total oxides of nitrogen. Since the role of atmospheric chemical reactions is to make the responses non-linearly dependent on the emissions control, we seek to establish the magnitude and sign of the effects that this non-linearity might cause. We develop a quantitative approach to analysing the non-linearity in the data. Polynomial fits have been developed for the empirical ratio NO 2 :NO x (the 'yield'). They describe nitrogen dioxide concentrations using total oxides of nitrogen. The new functions have the important feature of increased yield in winter episodes. Simpler functions tend to omit this feature of the yields at the highest hourly concentrations. Based on this study, the hourly nitrogen dioxide objective in the UK may require emissions control of no more than about 50% on total oxides of nitrogen at the most polluted sites: other sites require less or even no control. (Author)

Nitrogen-doped graphene by ball-milling graphite with melamine for energy conversion and storage

International Nuclear Information System (INIS)

Xue, Yuhua; Chen, Hao; Qu, Jia; Dai, Liming

2015-01-01

N-doped graphene was prepared by ball milling of graphite with melamine. It was found that ball-milling reduced the size of graphite particles from 30 to 1 μm and facilitated the exfoliation of the resultant small particles into few-layer N-doped graphene nanosheets under ultrasonication. The as-prepared N-doped graphene nanoplatelets (NGnPs) exhibited a nitrogen content as high as 11.4 at.%, making them attractive as efficient electrode materials in supercapacitors for energy storage and as highly-active metal-free catalysts for oxygen reduction in fuel cells for energy conversion. (paper)

The strictest energy requirements in the world

DEFF Research Database (Denmark)

Lauridsen, Erik Hagelskjær; Jensen, Jens Stissing

2013-01-01

50 years of progressively strengthened energy requirements in the Danish building code appear to be a success, as the energy consumption has remained constant despite an increase in the total area in requirement of heating. This article however argues that the building code mechanism is heavily...... influenced by path dependent regime structuration processes, and that the mechanism constitutes a barrier to more radical developments within low energy housing. Few and poorly organized frontrunner activities within low energy housing have accordingly taken place in a Danish context during the past decades....... Finally it is proposed that the current development within the energy system provides opportunities for cultivating an improved transitional awareness and for carrying out experimental activities that may challenge the path dependencies of prevailing regime structuration processes....

Factorial estimation of energy requirement for egg production

DEFF Research Database (Denmark)

Chwalibog, André

1992-01-01

Based on balance and respiration measurements with 60 White Leghorns during the laying period from 27 to 48 wk of age, a factorial method for estimating the energy requirement for egg production is proposed. The present experiment showed that the deposition of fat and energy increased during...... the laying period, but protein deposition slightly decreased. It has been shown that the efficiency of ME utilization for fat energy deposition is higher than for protein energy deposition in the egg. Because the proportions of protein and fat differ during the laying period, and because energy utilization...... is different between protein and fat, the ME requirement was calculated as the sum of ME for maintenance and the partial requirements for protein, fat, and carbohydrate deposition. For practical applications, functions for prediction of protein (OP), fat (OF), and energy (OE) in eggs during the laying period...

Cost-optimal levels for energy performance requirements

DEFF Research Database (Denmark)

Thomsen, Kirsten Engelund; Aggerholm, Søren; Kluttig-Erhorn, Heike

2011-01-01

The CA conducted a study on experiences and challenges for setting cost optimal levels for energy performance requirements. The results were used as input by the EU Commission in their work of establishing the Regulation on a comparative methodology framework for calculating cost optimal levels...... of minimum energy performance requirements. In addition to the summary report released in August 2011, the full detailed report on this study is now also made available, just as the EC is about to publish its proposed Regulation for MS to apply in their process to update national building requirements....

Energy Requirements for Biomass Harvest and Densification

Directory of Open Access Journals (Sweden)

Kevin Shinners

2018-03-01

Full Text Available This research quantified the unit and bulk density of several biomass crops across a variety of harvest and processing methods, as well as the energy and fuel requirements for these operations. A load density of approximately 240 kg·m−3 is needed to reach the legal weight limit of most transporters. Of the three types of balers studied, only the high density (HD large square baler achieved this target density. However, the specific energy and fuel requirements increased exponentially with bale density, and at the maximum densities for corn stover and switchgrass, the dry basis energy and fuel requirements ranged from 4.0 to 5.0 kW·h·Mg−1 and 1.2 to 1.4 L·Mg−1, respectively. Throughputs of tub grinders when grinding bales was less than any other harvesting or processing methods investigated, so specific energy and fuel requirements were high and ranged from 13 to 32 kW·h·Mg−1 and 5.0 to 11.3 L·Mg−1, respectively. Gross size-reduction by pre-cutting at baling increased bale density by less than 6% and increased baling energy requirements by 11% to 22%, but pre-cut bales increased the tub grinder throughput by 25% to 45% and reduced specific fuel consumption for grinding by 20% to 53%. Given the improvement in tub grinder operation, pre-cutting bales should be considered as a means to increase grinder throughput. Additional research is needed to determine the energy required to grind high density pre-cut bales at high throughputs so that better estimates of total energy required for a high density bale system can be made. An alternative bulk feedstock system was investigated that involved chopping moist biomass crops with a precision-cut forage harvester, compacting the bulk material in a silo bag, and then segmenting the densified material into modules optimized for efficient transport. The specific fuel use for chopping and then compacting biomass crops in the silo bag ranged from 1.6 to 3.0 L·Mg−1 and 0.5 to 1.3 L·Mg−1

Bacterial nitrogen fixation in sand bioreactors treating winery wastewater with a high carbon to nitrogen ratio.

Science.gov (United States)

Welz, Pamela J; Ramond, Jean-Baptiste; Braun, Lorenz; Vikram, Surendra; Le Roes-Hill, Marilize

2018-02-01

Heterotrophic bacteria proliferate in organic-rich environments and systems containing sufficient essential nutrients. Nitrogen, phosphorus and potassium are the nutrients required in the highest concentrations. The ratio of carbon to nitrogen is an important consideration for wastewater bioremediation because insufficient nitrogen may result in decreased treatment efficiency. It has been shown that during the treatment of effluent from the pulp and paper industry, bacterial nitrogen fixation can supplement the nitrogen requirements of suspended growth systems. This study was conducted using physicochemical analyses and culture-dependent and -independent techniques to ascertain whether nitrogen-fixing bacteria were selected in biological sand filters used to treat synthetic winery wastewater with a high carbon to nitrogen ratio (193:1). The systems performed well, with the influent COD of 1351 mg/L being reduced by 84-89%. It was shown that the nitrogen fixing bacterial population was influenced by the presence of synthetic winery effluent in the surface layers of the biological sand filters, but not in the deeper layers. It was hypothesised that this was due to the greater availability of atmospheric nitrogen at the surface. The numbers of culture-able nitrogen-fixing bacteria, including presumptive Azotobacter spp. exhibited 1-2 log increases at the surface. The results of this study confirm that nitrogen fixation is an important mechanism to be considered during treatment of high carbon to nitrogen wastewater. If biological treatment systems can be operated to stimulate this phenomenon, it may obviate the need for nitrogen addition. Copyright © 2017 Elsevier Ltd. All rights reserved.

Trimethylamine and trimethylamine N-oxide are supplementary energy sources for a marine heterotrophic bacterium: implications for marine carbon and nitrogen cycling.

Science.gov (United States)

Lidbury, Ian D E A; Murrell, J Colin; Chen, Yin

2015-03-01

Bacteria of the marine Roseobacter clade are characterised by their ability to utilise a wide range of organic and inorganic compounds to support growth. Trimethylamine (TMA) and trimethylamine N-oxide (TMAO) are methylated amines (MA) and form part of the dissolved organic nitrogen pool, the second largest source of nitrogen after N2 gas, in the oceans. We investigated if the marine heterotrophic bacterium, Ruegeria pomeroyi DSS-3, could utilise TMA and TMAO as a supplementary energy source and whether this trait had any beneficial effect on growth. In R. pomeroyi, catabolism of TMA and TMAO resulted in the production of intracellular ATP which in turn helped to enhance growth rate and growth yield as well as enhancing cell survival during prolonged energy starvation. Furthermore, the simultaneous use of two different exogenous energy sources led to a greater enhancement of chemoorganoheterotrophic growth. The use of TMA and TMAO primarily as an energy source resulted in the remineralisation of nitrogen in the form of ammonium, which could cross feed into another bacterium. This study provides greater insight into the microbial metabolism of MAs in the marine environment and how it may affect both nutrient flow within marine surface waters and the flux of these climatically important compounds into the atmosphere.

Energy requirements of infants, children and adolescents

Science.gov (United States)

Energy requirements of infants, children and adolescents are defined as the amount of energy needed to balance total energy expenditure (TEE) at a desirable level of physical activity, and to support optimal growth and development consistent with long-term health. The latest FAO/WHO/UNU recommendati...

Application of the Open Cycle Stirling Engine Driven with Liquid Nitrogen for the Non-Polluting Automobiles

Directory of Open Access Journals (Sweden)

M.B. Kravchenko

2017-10-01

Full Text Available Progress on advancing technology of using liquid nitrogen for the non-polluting automobiles is reported. It is shown that the low exergy efficiency of the known engines fueled with liquid nitrogen has discredited the very idea of a cryomobile. The design of the open-cycle cryogenic Stirling engine is proposed. This engine allows extracting up to 57% of the exergy accumulated in liquid nitrogen. The method used to calculate of such open-cycle Stirling engine is described and the calculation results and discussion are presented. It is shown that 200 liters of liquid nitrogen is sufficient for 180 km range of cryomobile at speed of 55 km/h, while a full charge of the 300-kilogram battery of Nissan LEAF electric vehicle is sufficient for a range of 160 km. Use of liquid nitrogen or liquid air as an energy vector in a transport will not require scarce materials, and, in comparison with using of lithium-ion batteries or hydrogen, this will require less capital investment.

Corrosion behaviour of low energy, high temperature nitrogen ion ...

Indian Academy of Sciences (India)

primary ions were used and negative secondary ions were detected. A difference in the distribution of the CrN and the alleged N signal was observed and attributed to CrN acting as a diffusion barrier for nitrogen diffusion. It may be noted here that nitrogen does not form stable elemental negative ions [2] and is thus.

Energy and angular distributions of secondary electrons from 5--100-keV-proton collisions with hydrogen and nitrogen molecules

International Nuclear Information System (INIS)

Rudd, M.E.

1979-01-01

Cross sections for the ejection of electrons from hydrogen and nitrogen by protons have been measured as a function of the energy and angle of ejection of the electrons at incident proton energies of 5--70 keV and 100 keV for hydrogen. The range of angles measured was 10--160 0 and the electron energy range was 1.5--300 eV. The doubly differential cross sections were also integrated over angle, over electron energy, or over both to obtain singly differential and total cross sections for electron production. Average electron energies were also calculated from the data. The angular distributions of electrons are peaked in the forward direction but become more isotropic as the proton energy decreases. Nitrogen yields a more isotropic distribution than hydrogen. In this range of proton energies the cross sections integrated over angle are found to fall off approximately exponentially with electron energy, and a simple empirical equation has been found that describes the singly differential and total cross sections within a factor of 2 for several targets. A theoretical interpretation of this result in terms of the molecular promotion model is given in which Meyerhof's method of calculating cross sections for K-shell excitation is applied for the first time to the ionization of outer shells of atoms

Development of the world energy requirement until 2000

International Nuclear Information System (INIS)

Schmitt, D.

1977-01-01

In its final report entitled 'Energy Global Prospects 1985 - 2000' and in three technical reports the Workshop on Alternative Energy Strategies (WAES), which was attended by 70 experts from 15 countries, in the summer of this year published the first worldwide forecast of the energy requirement up to the year 2000. The uncertainties affecting the long term development caused the WAES to employ a scenario in which the variables were economic growth, price levels of energy (and oil, respectively), and energy policy. Additional variables included to describe the long term problems arising in meeting the energy requirement are the coal vs. nuclear power alternative, the gross additions to the oil reserves, and assumptions about OPEC production limits. In view of the long lead times of technological developments and the extraordinarily high capital investments involved, rethinking is necessary right now, according to the WAES study, to find a possibility to change to other sources of fossil energy, nuclear power and, finally, renewable sources of energy, in view of the impending scarcity of the most important present source of energy, i.e., oil. Since the chances to meet a growing energy requirement by natural gas are viewed sceptically and a major contribution of new sources of energy is not expected to come forth before the next century, coal and nuclear power will be the main sources of energy supply for a foreseeable period of time to come. (orig.) [de

Size effects on cation heats of formation. I. Methyl substitutions in nitrogenous compounds

International Nuclear Information System (INIS)

Leach, Sydney

2012-01-01

Graphical abstract: Heat of formation of cations as a function of ln(n) where n is the number of atoms in the ion: methyl substituted immonium cations. N = substitution at nitrogen sites, C = substitution at carbon sites. Highlights: ► Heats of formation of nitrogenous cations by graphical method relating to ion size. ► Methyl substitution in formamides, acetamides, immonium, amine, and imine cations. ► Methyl substitution in ammonium and amino cations. ► New studies ionization energies and heats of formation required in several cases. - Abstract: The heats of formation of molecular ions are often not known to better than 10 or 20 kJ/mol. The present study on nitrogenous compounds adopts the graphical approach of Holmes and Lossing which relates cation heats of formation to cation size. A study of methyl substitution in formamides and acetamides is followed by an examination of heat of formation data on carbon-site and nitrogen-site methyl substitution in immonium, amine, imine, ammonium and amino cations. The results provide tests of the validity of this graphical method and also suggest investigating or re-investigating the ionization energies and the heats of formation of several of the molecules studied.

Prediction of the metabolizable energy requirements of free-range laying hens.

Science.gov (United States)

Brainer, M M A; Rabello, C B V; Santos, M J B; Lopes, C C; Ludke, J V; Silva, J H V; Lima, R A

2016-01-01

This experiment was conducted with the aim of estimating the ME requirements of free-range laying hens for maintenance, weight gain, and egg production. These experiments were performed to develop an energy requirement prediction equation by using the comparative slaughter technique and the total excreta collection method. Regression equations were used to relate the energy intake, the energy retained in the body and eggs, and the heat production of the hens. These relationships were used to determine the daily ME requirement for maintenance, the efficiency energy utilization above the requirements for maintenance, and the NE requirement for maintenance. The requirement for weight gain was estimated from the energy content of the carcass, and the diet's efficiency energy utilization was determined from the weight gain, which was measured during weekly slaughter. The requirement for egg production was estimated by considering the energy content of the eggs and the efficiency of energy deposition in the eggs. The requirement and efficiency energy utilization for maintenance were 121.8 kcal ME/(kg∙d)and 0.68, respectively. Similarly, the NE requirement for maintenance was 82.4 kcal ME/(kg∙d), and the efficiency energy utilization above maintenance was 0.61. Because the carcass body weight and energy did not increase during the trial, the weight gain could not be estimated. The requirements for egg production requirement and efficiency energy utilization for egg production were 2.48 kcal/g and 0.61, respectively. The following energy prediction equation for free-range laying hens (without weight gain) was developed: ME /(hen ∙ d) = 121.8 × W + 2.48 × EM, in which W = body weight (kg) and EM = egg mass (g/[hen ∙ d]).

Creation of nitrogen-vacancy centres in diamond with high resolution

Energy Technology Data Exchange (ETDEWEB)

Pezzagna, Sebastien; Meijer, Jan [Rubion, Ruhr-Universitaet Bochum (Germany); Wildanger, Dominik; Hell, Stefan W. [Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, Goettingen (Germany); Mazarov, Paul; Wieck, Andreas D. [Lehrstuhl fuer Angewandte Festkoerperphysik, Ruhr-Universitaet Bochum (Germany); Naydenov, Boris; Jelezko, Fedor; Wrachtrup, Joerg [3. Institute of Physics, University of Stuttgart (Germany)

2010-07-01

Nowadays, diamond and the nitrogen-vacancy (NV) colour centres constitute the best solid-state system in view of quantum-computing applications. It has also been shown recently that single NV centres could be used as nanoscale magnetic sensors. Such applications require the creation of single NV centres with very high resolution and with a high efficiency. The nano-implanter at the university of Bochum provides low energy nitrogen ions which can be implanted through a hole pierced in the tip of an atomic force microscope. Ultrapure diamond samples have been implanted with spot sizes of 50nm and less. Stimulated Emission Depletion (STED) microscopy has been used to characterise and resolve the implanted spots.

Effects of high energy nitrogen implantation on stainless steel microstructure

Science.gov (United States)

Pelletier, H.; Mille, P.; Cornet, A.; Grob, J. J.; Stoquert, J. P.; Muller, D.

1999-01-01

Low energy ion implantation is known to improve chemical and mechanical surface properties of metals. This treatment is often used to enhance wear and corrosion resistance or mechanical life-time of fatigue test of stainless steel or titanium alloys. The aim of this work is to investigate these effects at higher energy, for which deeper (and still not well understood) modifications occur. High fluence (10 18 cm -2) 15N and 14N implantations at 1 MeV have been performed in the 316LL stainless steel and some specimen have been annealed in the 200-500°C temperature range. Nitrogen concentration distribution, structure, morphology and microhardness have been examined with Nuclear Resonance Analysis, Grazing Incidence X-Ray Diffraction and Nanoindentation, respectively. Precipitates of steel and chromium nitride phases and a superficial martensitic transformation can be observed, leading to a significant increase of hardness. The best result is obtained after one hour annealing at 425°C, due to a larger and more homogeneous repartition of nitride species. In this case, a near surface accumulation is observed and explained in terms of diffusion and precipitation mechanisms.

Respiration and nitrogen assimilation: targeting mitochondria-associated metabolism as a means to enhance nitrogen use efficiency.

Science.gov (United States)

Foyer, Christine H; Noctor, Graham; Hodges, Michael

2011-02-01

Considerable advances in our understanding of the control of mitochondrial metabolism and its interactions with nitrogen metabolism and associated carbon/nitrogen interactions have occurred in recent years, particularly highlighting important roles in cellular redox homeostasis. The tricarboxylic acid (TCA) cycle is a central metabolic hub for the interacting pathways of respiration, nitrogen assimilation, and photorespiration, with components that show considerable flexibility in relation to adaptations to the different functions of mitochondria in photosynthetic and non-photosynthetic cells. By comparison, the operation of the oxidative pentose phosphate pathway appears to represent a significant limitation to nitrogen assimilation in non-photosynthetic tissues. Valuable new insights have been gained concerning the roles of the different enzymes involved in the production of 2-oxoglutarate (2-OG) for ammonia assimilation, yielding an improved understanding of the crucial role of cellular energy balance as a broker of co-ordinate regulation. Taken together with new information on the mechanisms that co-ordinate the expression of genes involved in organellar functions, including energy metabolism, and the potential for exploiting the existing flexibility for NAD(P)H utilization in the respiratory electron transport chain to drive nitrogen assimilation, the evidence that mitochondrial metabolism and machinery are potential novel targets for the enhancement of nitrogen use efficiency (NUE) is explored.

Assessment of nitrogen and phosphorus flows in agricultural and urban systems in a small island under limited data availability

NARCIS (Netherlands)

Firmansyah, I.; Spiller, M.; Ruijter, De F.J.; Carsjens, G.J.; Zeeman, G.

2017-01-01

Nitrogen (N) and phosphorus (P) are two essential macronutrients required in agricultural production. The
major share of this production relies on chemical fertilizer that requires energy and relies on limited resources
(P). Since these nutrients are lost to the environment, there is a need

Toward nitrogen neutral biofuel production.

Science.gov (United States)

Huo, Yi-Xin; Wernick, David G; Liao, James C

2012-06-01

Environmental concerns and an increasing global energy demand have spurred scientific research and political action to deliver large-scale production of liquid biofuels. Current biofuel processes and developing approaches have focused on closing the carbon cycle by biological fixation of atmospheric carbon dioxide and conversion of biomass to fuels. To date, these processes have relied on fertilizer produced by the energy-intensive Haber-Bosch process, and have not addressed the global nitrogen cycle and its environmental implications. Recent developments to convert protein to fuel and ammonia may begin to address these problems. In this scheme, recycling ammonia to either plant or algal feedstocks reduces the demand for synthetic fertilizer supplementation. Further development of this technology will realize its advantages of high carbon fixation rates, inexpensive and simple feedstock processing, in addition to reduced fertilizer requirements. Copyright © 2011 Elsevier Ltd. All rights reserved.

Experimental research on rock fracture failure characteristics under liquid nitrogen cooling conditions

Science.gov (United States)

Gao, Feng; Cai, Chengzheng; Yang, Yugui

2018-06-01

As liquid nitrogen is injected into a wellbore as fracturing fluid, it can rapidly absorb heat from warmer rock and generate cryogenic condition in downhole region. This will alter the physical conditions of reservoir rocks and further affect rock failure characteristics. To investigate rock fracture failure characteristics under liquid nitrogen cooling conditions, the fracture features of four types of sandstones and one type of marble were tested on original samples (the sample without any treatment) and cryogenic samples (the samples just taken out from the liquid nitrogen), respectively. The differences between original samples and cryogenic samples in load-displacement curves, fracture toughness, energy evolution and the crack density of ruptured samples were compared and analyzed. The results showed that at elastic deformation stage, cryogenic samples presented less plastic deformation and more obvious brittle failure characteristics than original ones. The average fracture toughness of cryogenic samples was 10.47%-158.33% greater than that of original ones, indicating that the mechanical strength of rocks used were enhanced under cooling conditions. When the samples ruptured, the cryogenic ones were required to absorb more energy and reserve more elastic energy. In general, the fracture degree of cryogenic samples was higher than that of original ones. As the samples were entirely fractured, the crack density of cryogenic samples was about 536.67% at most larger than that of original ones. This indicated that under liquid nitrogen cooling conditions, the stimulation reservoir volume is expected to be improved during fracturing. This work could provide a reference to the research on the mechanical properties and fracture failure of rock during liquid nitrogen fracturing.

Stakeholder requirements for commercially successful wave energy converter farms

Energy Technology Data Exchange (ETDEWEB)

Babarit, Aurélien; Bull, Diana; Dykes, Katherine; Malins, Robert; Nielsen, Kim; Costello, Ronan; Roberts, Jesse; Bittencourt Ferreira, Claudio; Kennedy, Ben; Weber, Jochem

2017-12-01

In this study, systems engineering techniques are applied to wave energy to identify and specify stakeholders' requirements for a commercially successful wave energy farm. The focus is on the continental scale utility market. Lifecycle stages and stakeholders are identified. Stakeholders' needs across the whole lifecycle of the wave energy farm are analyzed. A list of 33 stakeholder requirements are identified and specified. This list of requirements should serve as components of a technology performance level metric that could be used by investors and funding agencies to make informed decisions when allocating resources. It is hoped that the technology performance level metric will accelerate wave energy conversion technology convergence.

Effect of synchronizing the rate of degradation of dietary energy and nitrogen release on growth performance in Brahman cattle

Directory of Open Access Journals (Sweden)

Virote Pattarajinda

2006-01-01

Full Text Available The objective of this research was to determine the effect of synchronizing the rate of degradation of dietary energy and nitrogen release on growth performance in Brahman beef cattle. Fifteen Brahman cattle, 1.5 years old, with an average initial body weight of 184.8±11.1 kg were assigned to one of three treatments according to a randomized complete block design. Dietary treatments contained 3 levels of synchrony index (0.39, 0.56 and 0.74 that were derived from laboratory chemical composition analysis and degradation kinetics using nylon bag technique. Diets were fed at the rate of 2.5% BW by separate concentrate and roughage. Average daily gain increased linearly (P<0.05 with increase levels of synchrony index in the diets. The digestibility of dry matter, organic matter and neutral detergent fiber increased linearly (P<0.01. The digestibility of acid detergent fiber increased linearly (P<0.05. Ruminal total volatile fatty acids concentration increased linearly (P<0.05 at 6 h post feeding. Higher concentration and fluctuation of ruminal ammonia nitrogen and blood urea nitrogen were observed in animals that received lower synchrony index in their diets. Rumen microbial population tended to increase with diets having higher levels of synchrony index. The results indicated that synchronized rate of dietary energy and nitrogen degradation improved ruminal fermentation and digestibility, thus this increased the growth rate in Brahman cattle fed with ricestraw- based diets.

Improving cost-effectiveness and mitigating risks of renewable energy requirements

Science.gov (United States)

Griffin, James P.

Policy makers at the federal and state levels of government are debating actions to reduce U.S. greenhouse gas emissions and dependence on oil as an energy source. Several concerns drive this debate: sharp rises in energy prices, increasing unease about the risks of climate change, energy security, and interest in expanding the domestic renewable energy industry. Renewable energy requirements are frequently proposed to address these concerns, and are currently in place, in various forms, at the federal and state levels of government. These policies specify that a certain portion of the energy supply come from renewable energy sources. This dissertation focuses on a specific proposal, known as 25 X 25, which requires 25% of electricity and motor vehicle transportation fuels supplied to U.S. consumers to come from renewable energy sources, such as wind power and ethanol, by 2025. This dissertation builds on prior energy policy analysis, and more specifically analyses of renewable energy requirements, by assessing the social welfare implications of a 25 x 25 policy and applying new methods of uncertainty analysis to multiple policy options decision makers can use to implement the policy. These methods identify policy options that can improve the cost-effectiveness and reduce the risks of renewable energy requirements. While the dissertation focuses on a specific policy, the research methods and findings are applicable to other renewable energy requirement policies. In the dissertation, I analyze six strategies for implementing a 25 x 25 policy across several hundred scenarios that represent plausible futures for uncertainties in energy markets, such as renewable energy costs, energy demand, and fossil fuel prices. The strategies vary in the availability of resources that qualify towards the policy requirement and the use of a "safety valve" that allows refiners and utilities to pay a constant fee after renewable energy costs reach a predetermined threshold. I test

Biexciton emission from single isoelectronic traps formed by nitrogen-nitrogen pairs in GaAs

Energy Technology Data Exchange (ETDEWEB)

Takamiya, Kengo; Fukushima, Toshiyuki; Yagi, Shuhei; Hijikata, Yasuto; Yaguchi, Hiroyuki [Graduate School of Science and Engineering, Saitama University, 255 Shimo-Okubo, Sakura-ku , Saitama 338-8570 (Japan); Mochizuki, Toshimitsu; Yoshita, Masahiro; Akiyama, Hidefumi [Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan); Kuboya, Shigeyuki; Onabe, Kentaro [Department of Advanced Materials Science, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan); Katayama, Ryuji [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)

2013-12-04

We have studied photoluminescence (PL) from individual isoelectronic traps formed by nitrogen-nitrogen (NN) pairs in GaAs. Sharp emission lines due to exciton and biexciton were observed from individual isoelectronic traps in nitrogen atomic-layer doped (ALD) GaAs. The binding energy of biexciton bound to individual isoelectronic traps was approximately 8 meV. Both the exciton and biexciton luminescence lines show completely random polarization and no fine-structure splitting. These results are desirable to the application to the quantum cryptography used in the field of quantum information technology.

Nitrogen compounds behavior under irradiation environment

International Nuclear Information System (INIS)

Ichikawa, Nagayoshi; Takagi, Junichi; Yotsuyanagi, Tadasu

1991-01-01

Laboratory experiments were performed to evaluate nitrogen compounds behavior in liquid phase under irradiation environments. Nitrogen compounds take a chemical form of ammonium ion under reducing condition by gamma irradiation, whereas ammonium ions are rather stable even under oxidizing conditions. Key reactions were pointed out and their reaction rate constants and activation energies were estimated through computer code simulation. A reaction scheme for nitrogen compounds including protonate reaction was proposed. (author)

Variations in the Use of Resources for Food: Land, Nitrogen Fertilizer and Food Nexus

Directory of Open Access Journals (Sweden)

María José Ibarrola-Rivas

2016-12-01

Full Text Available Future dietary changes will increase the global demand for agricultural resources per person. Food production requires several resources which are interrelated: land, water, nutrients and energy. Other studies have calculated the per capita requirements of only one resource (nitrogen or land. In this paper, we combine several parameters (diets, production systems and nitrogen-land trade-off in one analysis in order to provide a more integrated assessment of the impacts of the use of agricultural resources for food. We estimated the trade-off between the per capita use of synthetic nitrogen fertilizer and crop land. With our methodology, we are able to identify separately the impacts of the type of diet and of the type of production system. We use national level data of five countries as examples of global extremes: from extensive to highly intensive systems, and from very basic diets to very affluent diets. The present differences in diets and production systems result in large differences in the per capita use of resources which ranges from 3 to 30 kg of nitrogen fertilizer use per person, and from 1800 to 4500 m2 of arable land use per person. As the results show, in 2050, the average per capita availability of crop land will not be enough to produce food for affluent diets with present production systems. Our results are useful to assess future requirements of nitrogen fertilizer for the limited land available on the planet.

Studies on nitrogen retention in growing pigs

DEFF Research Database (Denmark)

Thorbek, G; Henckel, S; Chwalibog, André

1987-01-01

Nitrogen retention (RN) was measured in 60 barrows of Danish Landrace and a total of 470 balance periods was carried out during the growth period from 20 to 85 kg live weight. In the first serie (Expt A) six different feed compounds of high biological value (HBV) were fed to 48 barrows, while...... in the second serie (Expt B) 12 barrows were measured on feed compounds of HBV or low biological value (LBV). Three different levels of gross energy were used in Expt B. Individual differences of 10-20% in the pigs capability for nitrogen retention were observed. Nitrogen retention increased from 12 to 21 g N....../d on the HBV-compounds and was not influenced by increasing nitrogen or energy intake. Nitrogen retention was curvilinear in relation to metabolic live weight (kg0.75) in both series. A parabolic function on kg0.75 gave the best fit to the data with the following regression equations: Expt A + B: RN, g/d = 1...

Nitrogen Soil Testing for Corn in Virginia

OpenAIRE

Evanylo, Gregory K.; Alley, Marcus M., 1947-

2009-01-01

An adequate supply of plant-available nitrogen (N) is crucial for efficient corn production, and corn N requirements are greater than any other nutrient. This publication reviews the link between nitrogen and corn production, nitrogen behavior, soil testing, test procedures and recommendations.

Influence of different fibre sources on digestibility and nitrogen and energy balances in growing pigs

DEFF Research Database (Denmark)

Hansen, Michael Jørgen; Chwalibog, André; Tauson, Anne-Helene

2006-01-01

The present study was undertaken to investigate how three different fibre sources, sugar beet pulp, soya bean hulls and pectin residue, constituting 15% of diets for growing pigs, influenced daily body gain, feed conversion, apparent faecal digestibility and nitrogen and energy balances. Eight......) and energy were significantly lower for the fibre diets (OM: 0.81-0.85; energy: 0.78-0.83) compared to the control diet (OM: 0.88; energy: 0.86). The apparent faecal digestibility of crude protein (CP) was lower for the fibre diets (0.71-0.78) compared to the control diet (0.83), although it was only...... significantly lower for the sugar beet pulp and pectin residue diets. The pectin residue diet, which contained the highest amount of dietary fibre, lignin and insoluble non-starch polysaccharides, had the lowest digestibility of OM, CP and energy. There was a tendency (p = 0.07) for a diet effect on retained...

Requirements for an energy policy

International Nuclear Information System (INIS)

Conant, M.A.

1987-01-01

The central issue facing the US today lies in the rise of oil imports. No supergiant (5 billion barrels) oil discoveries have been made in the US. Production from existing fields is declining. The 1985-86 oil price collapse from $26 to less than $15 per barrel had a disastrous effect on the budgets of smaller oil companies which do most of the exploring, and on the service industry. Budgets for overseas exploration has been generally sustained. Oil prices are not expected to sustain domestic exploration. Gulf oil sources will, in the next five years, supply some 75 percent of all oil in international trade. Without an energy policy, involvement in Middle East oil will grow exponentially, as will the needs of others for Gulf oil. The natural gas situation is different, with a spare producing capacity of one trillion cubic feet this year, which could double next year. Natural gas deregulation has created an unbelievable mess in the requirements of producers/suppliers and purchasers to have dependable business arrangements. Coal is plentiful and will be until the end of time. Public opposition to emission problems and the greenhouse effect are an obstacle to greater use of coal. The nuclear option may be dead, with no new orders since 1978. Statistics are provided on proven world reserves of conventional crude oil, recoverable heavy oils, tar sands, and shale oil; which indicates for the long term an ability to transform the Geopolitics of oil away from the middle east. Energy options require energy R ampersand D, use of Alaskan gas, conservation and efficiency in energy use, strategic reserves, close energy relations with allies, and a government-industry link which insures meeting the US oil needs from the Western Hemisphere

Energy requirements of tire pulling.

Science.gov (United States)

Fredriksen, Per M; Mamen, Asgeir

2017-10-01

We have investigated the effect using walking poles and pulling tires at 4 and 6 km·h-1 (1.11 and 1.67 m·s-1) speeds on oxygen uptake (V̇O2) and heart rate. Eleven subjects, 6 males, with a mean (SD) age of 25.2 (6.9) years participated in field tests involving walking without poles, walking with poles and tire pulling with poles. Increasing the load caused the largest increases in energy demand, more than 4 MET. Speed increase also caused substantial energy increase, approximately 4 MET. Increasing the inclination only modestly increased the oxygen uptake, approximately 2 MET. In both level walking and uphill walking, using poles marginally increased oxygen uptake compared to working without poles. Pulling one tire (12.5 kg) required an oxygen uptake of 27 (4) mL·kg-1·min-1 at 4 km·h-1 and 0% inclination. Adding one more tire (6 kg) drove the oxygen uptake further up to 39 (4) mL·kg-1·min-1. This is close to the requirement of level running at 10.5 km·h-1. Pulling both tires at 6 km·h-1 and 5% inclination required a V̇O2 of 54 (6) mL·kg-1·min-1, equal to running uphill at 5% inclination and 12.5 km·h-1 speed. Heart rate rose comparably with oxygen uptake. At 4 km·h-1 and 0% inclination the increase was 29 bpm, from 134 (21) to 163 (22) bpm when going from pulling one tire to two tires. In the hardest exercise, 6 km·h-1 and 5% inclination, heart rate reached 174 (14) bpm. The study showed that tire pulling even at slow speeds has an energy requirement that is so large that the activity may be feasible as endurance training.

Precise measurement of the absolute fluorescence yield of nitrogen in air. Consequences on the detection of ultra-high energy cosmic rays; Mesure precise du rendement absolu de la fluorescence de l'azote dans l'air. Consequences sur la detection des rayons cosmiques d'ultra-haute energie

Energy Technology Data Exchange (ETDEWEB)

Lefeuvre, G

2006-07-15

The study of the energy spectrum of ultra-high energy cosmic rays (E > 10{sup 20} eV) requires to determine the energy with much more precision than what is currently achieved. The shower of particles created in the atmosphere can be detected either by sampling particle on the ground, or by detecting the fluorescence induced by the excitation of nitrogen by shower electrons. At present, the measurement of the fluorescence is the simplest and the most reliable method, since it does not call upon hadronic physics laws at extreme energies, a field still inaccessible to accelerators. The precise knowledge of the conversion factor between deposited energy and the number of fluorescence photons produced (the yield) is thus essential. Up to now, it has been determined with an accuracy of 15 % only. This main goal of this work is to measure this yield to better than 5 per cent. To do this, 1 MeV electrons from a radioactive source excite nitrogen of the air. The accuracy has been reached thanks to the implementation of a new method for the absolute calibration of the photomultipliers detecting the photons, to better than 2 per cent. The fluorescence yield, measured and normalized to 0.85 MeV, 760 mmHg and 15 Celsius degrees, is (4.23 {+-} 0.20) photons per meter, or (20.46 {+-} 0.98) photons per deposited MeV. In addition, and for the first time, the absolute fluorescence spectrum of nitrogen excited by a source has been measured with an optical grating spectrometer. (author)

Energy requirement for fine grinding of torrefied wood

Energy Technology Data Exchange (ETDEWEB)

Repellin, Vincent; Govin, Alexandre; Guyonnet, Rene [Department of Powder and Multi-Components Materials (PMMC), SPIN Research Center, Ecole des Mines de Saint Etienne (EMSE), 158 Cours Fauriel, F-42023 Saint-Etienne (France); Rolland, Matthieu [Process Developments and Engineering Division, Chemical Engineering Department, Institut Francais du Petrole (IFP-Lyon), F-69390 Vernaison (France)

2010-07-15

The purpose of this study is to investigate the influence of torrefaction on wood grinding energy. Wood chips were torrefied at different temperatures and durations. The energy required to obtain fine powder was measured. Particle size analyses were carried out on each powder sample. It is showed that torrefaction decreases both grinding energy and particle size distribution. A criterion to compare grindability of natural and torrefied wood is proposed. It takes into account both grinding energy and particle size distribution. It accounts the energy required for grinding particles to sizes inferior to 200 {mu}m, for given grinding conditions. Torrefaction is characterised by the anhydrous weight loss (AWL) of wood. For AWL inferior to around 8%, grinding energy decreases fast. Over 8%, grinding energy decreases at a slow rate. Particle size distribution decreases linearly as the AWL increases. Both for spruce and beech, the grinding criterion is decreased of 93% when the AWL is around 28%. (author)

Developments in nitrogen generators

International Nuclear Information System (INIS)

Ayres, C.L.; Abrardo, J.M.; Himmelberger, L.M.

1984-01-01

Three process cycles for the production of nitrogen by the cryogenic separation of air are described in detail. These cycles are: (1) a waste expander cycle; (2) an air expander cycle; and (3) a cycle for producing large quantities of gaseous nitrogen. Each cycle has distinct advantages for various production ranges and delivery pressures. A dicussion of key parameters that must be considered when selecting a cycle to meet specific product requirements is presented. The importance of high plant reliability and a dependable liquid nitrogen back up system is also presented. Lastly, a discussion of plant safety dealing with the hazards of nitrogen, enriched oxygen, and hydrocarbons present in the air is reviewed

Replaceable liquid nitrogen piping

International Nuclear Information System (INIS)

Yasujima, Yasuo; Sato, Kiyoshi; Sato, Masataka; Hongo, Toshio

1982-01-01

This liquid nitrogen piping with total length of about 50 m was made and installed to supply the liquid nitrogen for heat insulating shield to three superconducting magnets for deflection and large super-conducting magnet for detection in the π-meson beam line used for high energy physics experiment in the National Laboratory for High Energy Physics. The points considered in the design and manufacture stages are reported. In order to minimize the consumption of liquid nitrogen during transport, vacuum heat insulation method was adopted. The construction period and cost were reduced by the standardization of the components, the improvement of welding works and the elimination of ineffective works. For simplifying the maintenance, spare parts are always prepared. The construction and the procedure of assembling of the liquid nitrogen piping are described. The piping is of double-walled construction, and its low temperature part was made of SUS 316L. The super-insulation by aluminum vacuum evaporation and active carbon were attached on the external surface of the internal pipe. The final leak test and the heating degassing were performed. The tests on evacuation, transport capacity and heat entry are reported. By making the internal pipe into smaller size, the piping may be more efficient. (Kako, I.)

Nuclear Energy, Long Term Requirements

International Nuclear Information System (INIS)

Knapp, V.

2006-01-01

There are serious warnings about depletion of oil and gas and even more serious warnings about dangers of climate change caused by emission of carbon dioxide. Should developed countries be called to replace CO2 emitting energy sources as soon as possible, and the time available may not be longer then few decades, can nuclear energy answer the call and what are the requirements? Assuming optimistic contribution of renewable energy sources, can nuclear energy expand to several times present level in order to replace large part of fossil fuels use? Paper considers intermediate and long-term requirements. Future of nuclear power depends on satisfactory answers on several questions. First group of questions are those important for near and intermediate future. They deal with economics and safety of nuclear power stations in the first place. On the same time scale a generally accepted concept for radioactive waste disposal is also required. All these issues are in the focus of present research and development. Safer and more economical reactors are targets of international efforts in Generation IV and INPRO projects, but aiming further ahead these innovative projects are also addressing issues such as waste reduction and proliferation resistance. However, even assuming successful technical development of these projects, and there is no reason to doubt it, long term and large-scale nuclear power use is thereby not yet secured. If nuclear power is to play an essential role in the long-term future energy production and in reduction of CO2 emission, than several additional questions must be replied. These questions will deal with long-term nuclear fuel sufficiency, with necessary contribution of nuclear power in sectors of transport and industrial processes and with nuclear proliferation safety. This last issue is more political then technical, thus sometimes neglected by nuclear engineers, yet it will have essential role for the long-term prospects of nuclear power. The

The discharge characteristics in nitrogen helicon plasma

Science.gov (United States)

Zhao, Gao; Wang, Huihui; Si, Xinlu; Ouyang, Jiting; Chen, Qiang; Tan, Chang

2017-12-01

Discharge characteristics of helicon plasma in nitrogen and argon-nitrogen mixtures were investigated experimentally by using a Langmuir probe, a B-dot probe, and an optical emission spectrum. Helicon wave discharge is confirmed by the changes of electron density and electromagnetic signal amplitude with the increasing RF power, which shows three discharge stages in nitrogen, corresponding to E-mode, H-mode, and W-mode discharges in helicon plasma, respectively. Discharge images in the radial cross section at different discharge modes through an intensified charge coupled device (ICCD) show a rapid increase in luminous intensity along with the RF power. When the nitrogen discharge is in the W-mode, the images show that the strongest luminance locates near the plasma boundary and no blue core appears in the axial center of tube, which is always observed in argon W-mode discharge. The "big blue" or blue core is a special character in helicon plasma, but it has not been observed in nitrogen helicon plasma. In nitrogen-argon mixtures, a weak blue core is observed in ICCD images since the nitrogen content is increased. The electric field turns to the periphery in the distribution of the radial field and the electron temperature decreases with the increasing nitrogen content, especially when the blue core disappears. The different behaviors of the electron impact and the energy consumption in nitrogen helicon plasma are suggested to be responsible for the decrease in electron energy and the change in the electric field distribution.

An approach to defining the energy requirements of dairy sheep

International Nuclear Information System (INIS)

Susmel, P.; Cuzzit, R.

1988-01-01

Evaluation of the interaction between nutrition and reproduction in Mediterranean sheep requires knowledge of the energy requirements of animals in different productive and reproductive stages. The available energy systems developed for temperate climates and genotypes are not directly applicable to Mediterranean breeds of dairy sheep. Using already available data, metabolizable energy requirements for these types of animals are proposed. (author). 59 refs, 9 tabs

The direct and indirect energy requirement of households in the European Union

International Nuclear Information System (INIS)

Reinders, A.H.M.E.; Vringer, K.; Blok, K.

2003-01-01

In this article we evaluate the average energy requirement of households in 11 EU member states. By investigating both the direct (electricity, natural gas, gasoline, etc.) and the indirect energy requirement, i.e. the energy embodied in consumer goods and services, we add to research done on only the direct household energy requirement. Our analysis is mainly based on data of expenditures of households and the associated energy intensities of consumer goods. We found that differences between countries in the total energy requirement of households are mainly due to differences in total household expenditure. In particular, the indirect energy requirement is linearly related to the total household expenditure. The share of direct energy to the total energy requirement in different countries varies from 34% up to 64%. Differences in climate do not fully account for this variation. Corrected for total household expenditure, indirect energy requirement may vary significantly per country in the consumption classes 'food, beverages and tobacco', 'recreation and culture', 'housing', and 'hotels, cafes and restaurants'

Investment requirements in the energy sector and their financing

Energy Technology Data Exchange (ETDEWEB)

Diehl, R; Radtke, G; Stoessel, R [Dresdner Bank A.G., Duesseldorf (Germany, F.R.)

1980-01-01

The authors investigate the investment requirements of the energy economy, especially for the Federal Republic Germany, but also for parts of the world. Possibilities for financing are shown which can be considered as assured, under certain conditions. Included are the investments and the capital requirements for the fossil energy-carriers (coal, brown coal, oil, natural gas), for the electricity economy and for the regenerativ energy sources (e.g. tidal energy, wind, solar radiation). The last chapter deals with financing the necessary investments in the energy sector, considering the financing structure, financial problems of individual branches and the development of the credit volume.

Metabolizable energy, nitrogen balance, and ileal digestibility of amino acids in quality protein maize for pigs

Science.gov (United States)

2014-01-01

Background To compare the nutritional value and digestibility of five quality protein maize (QPM) hybrids to that of white and yellow maize, two experiments were carried out in growing pigs. In experiment 1, the energy metabolizability and the nitrogen balance of growing pigs fed one of five QPM hybrid diets were compared against those of pigs fed white or yellow maize. In experiment 2, the apparent and standardized ileal digestibility (AID and SID, respectively) of proteins and amino acids from the five QPM hybrids were compared against those obtained from pigs fed white and yellow maize. In both experiments, the comparisons were conducted using contrasts. Results The dry matter and nitrogen intakes were higher in the pigs fed the QPM hybrids (P digestibility (P digestible lysine than normal maize. PMID:25045520

Studies on supplementary desalted mother liquor on digestibility of nutrients, ruminal fermentation, and energy and nitrogen balance in Thai native cattle.

Science.gov (United States)

Sakai, Takashi; Angthong, Wanna; Takeda, Motoharu; Oishi, Kazato; Hirooka, Hiroyuki; Kumagai, Hajime

2017-09-01

Four Thai native steers were used to determine the adequate levels of supplementary desalted mother liquor (DML) for energy and nitrogen balances and ruminal fermentation. The crude protein and sodium chloride contents of DML were 25.5% and 60.3% on a dry matter (DM) basis, respectively. A 4 × 4 Latin square design experiment was conducted by adding different amounts of DML to three experimental diets (T1: 1.1%, T2: 2.2%, T3: 3.4% sodium chloride concentration with supplementary DML on a DM basis) and comparing their effects with those of a control diet (C) containing 1.0% commercial salt on a DM basis. The animals were given the experimental diets and rice straw daily at 1.2% and 0.8% of body weight, respectively, on a DM basis. No significant differences in the apparent digestibility of nutrients were observed among treatments. T3 achieved the lowest nitrogen retention (P < 0.05), followed by C, T2 and T1. The ratios of energy retention to gross energy were higher in T1 and T3 than T2, and that in C was lowest (P < 0.05). Supplementary NaCl concentration at 1% and 2% can be replaced with DML without an adverse effect on the digestibility of nutrients or on the nitrogen and energy retention. © 2017 Japanese Society of Animal Science.

Short communication: Prediction of energy requirements of ...

African Journals Online (AJOL)

Data collected on metabolizable energy (ME) intake and growth performance of preruminant female kids of the Murciano-Granadina breed was used to assess the accuracy of the latest U. S. National Research Council (NRC) recommendations to predict their energy requirements. Female kids were fed a milk replacer ...

Life-Cycle Cost and Environmental Assessment of Decentralized Nitrogen Recovery Using Ion Exchange from Source-Separated Urine through Spatial Modeling.

Science.gov (United States)

Kavvada, Olga; Tarpeh, William A; Horvath, Arpad; Nelson, Kara L

2017-11-07

Nitrogen standards for discharge of wastewater effluent into aquatic bodies are becoming more stringent, requiring some treatment plants to reduce effluent nitrogen concentrations. This study aimed to assess, from a life-cycle perspective, an innovative decentralized approach to nitrogen recovery: ion exchange of source-separated urine. We modeled an approach in which nitrogen from urine at individual buildings is sorbed onto resins, then transported by truck to regeneration and fertilizer production facilities. To provide insight into impacts from transportation, we enhanced the traditional economic and environmental assessment approach by combining spatial analysis, system-scale evaluation, and detailed last-mile logistics modeling using the city of San Francisco as an illustrative case study. The major contributor to energy intensity and greenhouse gas (GHG) emissions was the production of sulfuric acid to regenerate resins, rather than transportation. Energy and GHG emissions were not significantly sensitive to the number of regeneration facilities. Cost, however, increased with decentralization as rental costs per unit area are higher for smaller areas. The metrics assessed (unit energy, GHG emissions, and cost) were not significantly influenced by facility location in this high-density urban area. We determined that this decentralized approach has lower cost, unit energy, and GHG emissions than centralized nitrogen management via nitrification-denitrification if fertilizer production offsets are taken into account.

Effect of nitrogen doping of graphene oxide on hydrogen and hydroxyl adsorption

Energy Technology Data Exchange (ETDEWEB)

Min, Byeong June; Jeong, Hae Kyung [Daegu University, Kyungsan (Korea, Republic of)

2014-05-15

We investigate how nitrogen-doping affects the hydrogen (H) and the hydroxyl (OH) adsorption on graphene oxide (GO) and on nitrogen-doped GO (NGO) via pseudopotential plane wave density functional calculations within the local spin density approximation. We find that the nitrogen doping brings about drastic changes in the hydrogen and the hydroxyl adsorption energetics, but its effects depend sensitively on the nitrogen configuration in NGO. The H and the OH adsorption energies are comparable only for pyrrolic NGO. In GO and quarternary NGO, the H adsorption energy is greater than the OH adsorption energy while the trend is reversed in pyridinic NGO. Also, the OH adsorption process is less affected by nitrogen-doping than the H adsorption is.

Investment requirements in the energy sector and their financing

International Nuclear Information System (INIS)

Diehl, R.; Radtke, G.; Stoessel, R.

1980-01-01

The authors investigate the investment requirements of the energy economy, especially for the Federal Republic Germany, but also for parts of the world. Possibilities for financing are shown which can be considered as assured, under certain conditions. Included are the investments and the capital requirements for the fossil energy-carriers (coal, brown coal, oil, natural gas), for the electricity economy and for the regenerativ energy sources (e.g. tidal energy, wind, solar radiation). The last chapter deals with financing the necessary investments in the energy sector, considering the financing structure, financial problems of individual branches and the development of the credit volume. (orig.) [de

Exhaustive Conversion of Inorganic Nitrogen to Nitrogen Gas Based on a Photoelectro-Chlorine Cycle Reaction and a Highly Selective Nitrogen Gas Generation Cathode.

Science.gov (United States)

Zhang, Yan; Li, Jinhua; Bai, Jing; Shen, Zhaoxi; Li, Linsen; Xia, Ligang; Chen, Shuai; Zhou, Baoxue

2018-02-06

A novel method for the exhaustive conversion of inorganic nitrogen to nitrogen gas is proposed in this paper. The key properties of the system design included an exhaustive photoelectrochemical cycle reaction in the presence of Cl - , in which Cl· generated from oxidation of Cl - by photoholes selectively converted NH 4 + to nitrogen gas and some NO 3 - or NO 2 - . The NO 3 - or NO 2 - was finally reduced to nitrogen gas on a highly selective Pd-Cu-modified Ni foam (Pd-Cu/NF) cathode to achieve exhaustive conversion of inorganic nitrogen to nitrogen gas. The results indicated total nitrogen removal efficiencies of 30 mg L -1 inorganic nitrogen (NO 3 - , NH 4 + , NO 3 - /NH 4 + = 1:1 and NO 2 - /NO 3 - /NH 4 + = 1:1:1) in 90 min were 98.2%, 97.4%, 93.1%, and 98.4%, respectively, and the remaining nitrogen was completely removed by prolonging the reaction time. The rapid reduction of nitrate was ascribed to the capacitor characteristics of Pd-Cu/NF that promoted nitrate adsorption in the presence of an electric double layer, eliminating repulsion between the cathode and the anion. Nitrate was effectively removed with a rate constant of 0.050 min -1 , which was 33 times larger than that of Pt cathode. This system shows great potential for inorganic nitrogen treatment due to the high rate, low cost, and clean energy source.

A forecast of energy requirements in South Africa

International Nuclear Information System (INIS)

Kotze, D.J.

1975-01-01

The aim of this paper is to evaluate the adequacy of South Africa's energy resources relative to projected demands. The forecasting procedure embraces the construction of suitable energy balances and the development of econometric demand models. An energy balance is employed which integrates supply and demand data on all forms of energy for a particular year. The demand side of the balance is divided into both final demand and demand by the conversion sector. Useful energy consumption in each sector is estimated by applying utilisation efficiency co-efficients to the physics energy content of each energy form. Total final demand is determined by developing sub-models for each sector of final demand including households, industry, mining and transport. In these sub-models, economic series representing the type of activity in the particular sub-sector, are used as explanatory variables. Further relationships, quantifying the contributions of each form of energy to the sectorial totals, are constructed. Having established the future value of final useful energy demand, total future production and final consumption is obtained. The forecast of primary energy requirements is therefore made via a reversed calculation from the final energy demand through all conversion processes to the primary energy stage. Once the future distribution of energy by source, form and end use sector is known it is possible to plan the optimum allocation of energy resources in the country. It is also possible to evaluate the life of indigenous energy resources, their adequacy, and import requirements

Energy-efficient houses built according to the energy performance requirements introduced in Denmark in 2006

DEFF Research Database (Denmark)

Tommerup, Henrik M.; Rose, Jørgen; Svendsen, Svend

2007-01-01

In order to meet new tighter building energy requirements introduced in Denmark in 2006 and prepare the way for future buildings with even lower energy consumption, single-family houses were built with the purpose to demonstrate that it is possible to build typical single-family houses with an en......% of the required and almost the level of typical passive houses.......In order to meet new tighter building energy requirements introduced in Denmark in 2006 and prepare the way for future buildings with even lower energy consumption, single-family houses were built with the purpose to demonstrate that it is possible to build typical single-family houses...... with an energy consumption that meets the demands without problems concerning building technology or economy. The paper gives a brief presentation of the houses and the applied energy-saving measures. The paper also presents results from measurements of the overall energy use, indoor climate and air tightness...

Production of nitrogen containing chemicals from cyanophycin

NARCIS (Netherlands)

Könst, P.M.

2011-01-01

Currently nitrogen containing bulk chemicals are produced from naphtha. However, as explained in Chapter 1 it would be more energy efficient, less capital intensive and eventually more economical to start from functionalized compounds that already have nitrogen incorporated, such as amino

Nitrogen-neutrality: a step towards sustainability

Science.gov (United States)

Leip, Adrian; Leach, Allison; Musinguzi, Patrick; Tumwesigye, Trust; Olupot, Giregon; Tenywa, John Stephen; Mudiope, Joseph; Hutton, Olivia; Cordovil, Claudia M. d. S.; Bekunda, Mateete; Galloway, James

2014-11-01

We propose a novel indicator measuring one dimension of the sustainability of an entity in modern societies: Nitrogen-neutrality. N-neutrality strives to offset Nr releases an entity exerts on the environment from the release of reactive nitrogen (Nr) to the environment by reducing it and by offsetting the Nr releases elsewhere. N-neutrality also aims to increase awareness about the consequences of unintentional releases of nitrogen to the environment. N-neutrality is composed of two quantified elements: Nr released by an entity (e.g. on the basis of the N footprint) and Nr reduction from management and offset projects (N offset). It includes management strategies to reduce nitrogen losses before they occur (e.g., through energy conservation). Each of those elements faces specific challenges with regard to data availability and conceptual development. Impacts of Nr releases to the environment are manifold, and the impact profile of one unit of Nr release depends strongly on the compound released and the local susceptibility to Nr. As such, N-neutrality is more difficult to conceptualize and calculate than C-neutrality. We developed a workable conceptual framework for N-neutrality which was adapted for the 6th International Nitrogen Conference (N2013, Kampala, November 2013). Total N footprint of the surveyed meals at N2013 was 66 kg N. A total of US 3050 was collected from the participants and used to offset the conference’s N footprint by supporting the UN Millennium Village cluster Ruhiira in South-Western Uganda. The concept needs further development in particular to better incorporate the spatio-temporal variability of impacts and to standardize the methods to quantify the required N offset to neutralize the Nr releases impact. Criteria for compensation projects need to be sharply defined to allow the development of a market for N offset certificates.

Nitrogen-neutrality: a step towards sustainability

International Nuclear Information System (INIS)

Leip, Adrian; Leach, Allison; Hutton, Olivia; Galloway, James; Musinguzi, Patrick; Tumwesigye, Trust; Olupot, Giregon; Stephen Tenywa, John; Mudiope, Joseph; Cordovil, Claudia M d S; Bekunda, Mateete

2014-01-01

We propose a novel indicator measuring one dimension of the sustainability of an entity in modern societies: Nitrogen-neutrality. N-neutrality strives to offset Nr releases an entity exerts on the environment from the release of reactive nitrogen (Nr) to the environment by reducing it and by offsetting the Nr releases elsewhere. N-neutrality also aims to increase awareness about the consequences of unintentional releases of nitrogen to the environment. N-neutrality is composed of two quantified elements: Nr released by an entity (e.g. on the basis of the N footprint) and Nr reduction from management and offset projects (N offset). It includes management strategies to reduce nitrogen losses before they occur (e.g., through energy conservation). Each of those elements faces specific challenges with regard to data availability and conceptual development. Impacts of Nr releases to the environment are manifold, and the impact profile of one unit of Nr release depends strongly on the compound released and the local susceptibility to Nr. As such, N-neutrality is more difficult to conceptualize and calculate than C-neutrality. We developed a workable conceptual framework for N-neutrality which was adapted for the 6th International Nitrogen Conference (N2013, Kampala, November 2013). Total N footprint of the surveyed meals at N2013 was 66 kg N. A total of US$ 3050 was collected from the participants and used to offset the conference’s N footprint by supporting the UN Millennium Village cluster Ruhiira in South-Western Uganda. The concept needs further development in particular to better incorporate the spatio-temporal variability of impacts and to standardize the methods to quantify the required N offset to neutralize the Nr releases impact. Criteria for compensation projects need to be sharply defined to allow the development of a market for N offset certificates. (paper)

Energie- en eiwitbehoefte van biologisch gehouden pluimvee = Energy and protein requirements of organic housed poultry

NARCIS (Netherlands)

Knegsel, van A.T.M.; Krimpen, van M.M.

2008-01-01

In this literature review, the physiological basis for possible differences in energy and protein requirements of organic versus conventional poultry is investigated. Energy need for maintenance of organic housed poultry seems to be increased, whereas protein requirements might not differ between

Deviation from normal Boltzmann distribution of high-lying energy levels of iron atom excited by Okamoto-cavity microwave-induced plasmas using pure nitrogen and nitrogen–oxygen gases

International Nuclear Information System (INIS)

Wagatsuma, Kazuaki

2015-01-01

This paper describes several interesting excitation phenomena occurring in a microwave-induced plasma (MIP) excited with Okamoto-cavity, especially when a small amount of oxygen was mixed with nitrogen matrix in the composition of the plasma gas. An ion-to-atom ratio of iron, which was estimated from the intensity ratio of ion to atomic lines having almost the same excitation energy, was reduced by adding oxygen gas to the nitrogen MIP, eventually contributing to an enhancement in the emission intensities of the atomic lines. Furthermore, Boltzmann plots for iron atomic lines were observed in a wide range of the excitation energy from 3.4 to 6.9 eV, indicating that plots of the atomic lines having lower excitation energies (3.4 to 4.8 eV) were well fitted on a straight line while those having more than 5.5 eV deviated upwards from the linear relationship. This overpopulation would result from any other excitation process in addition to the thermal excitation that principally determines the Boltzmann distribution. A Penning-type collision with excited species of nitrogen molecules probably explains this additional excitation mechanism, in which the resulting iron ions recombine with captured electrons, followed by cascade de-excitations between closely-spaced excited levels just below the ionization limit. As a result, these high-lying levels might be more populated than the low-lying levels of iron atom. The ionization of iron would be caused less actively in the nitrogen–oxygen plasma than in a pure nitrogen plasma, because excited species of nitrogen molecule, which can provide the ionization energy in a collision with iron atom, are consumed through collisions with oxygen molecules to cause their dissociation. It was also observed that the overpopulation occurred to a lesser extent when oxygen gas was added to the nitrogen plasma. The reason for this was also attributed to decreased number density of the excited nitrogen species due to collisions with oxygen

Incorporation of low energy activated nitrogen onto HOPG surface: Chemical states and thermal stability studies by in-situ XPS and Raman spectroscopy

Science.gov (United States)

Chandran, Maneesh; Shasha, Michal; Michaelson, Shaul; Hoffman, Alon

2016-09-01

In this paper we report the chemical states analysis of activated nitrogen incorporated highly oriented pyrolytic graphite (HOPG) surface under well-controlled conditions. Nitrogen incorporation is carried out by two different processes: an indirect RF nitrogen plasma and low energy (1 keV) N2+ implantation. Bonding configuration, concentration and thermal stability of the incorporated nitrogen species by aforesaid processes are systematically compared by in-situ X-ray photoelectron spectroscopy (XPS). Relatively large concentration of nitrogen is incorporated onto RF nitride HOPG surface (16.2 at.%), compared to N2+ implanted HOPG surface (7.7 at.%). The evolution of N 1s components (N1, N2, N3) with annealing temperature is comprehensively discussed, which indicates that the formation and reorganization of local chemical bonding states are determined by the process of nitridation and not by the prior chemical conditioning (i.e., amorphization or hydrogenation) of the HOPG surface. A combined XPS and Raman spectroscopy studies revealed that N2+ implantation process resulted in a high level of defects to the HOPG surface, which cannot be annealed-out by heat treatment up to 1000 °C. On the other hand, the RF nitrogen plasma process did not produce a high level of surface defects, while incorporating nearly the same amount of stable nitrogen species.

Atomistic study on the interaction of nitrogen and Mg lattice and the nitride formation in nanocrystalline Mg alloys synthesized using cryomilling process

International Nuclear Information System (INIS)

Nezafati, Marjan; Giri, Anit; Hofmeister, Clara; Cho, Kyu; Schneider, Matthew M.; Zhou, Le; Sohn, Yongho; Kim, Chang-Soo

2016-01-01

Cryomilling is a broadly applied technique to synthesize nanostructured alloys and composites through powder metallurgy (PM) processing. Understanding the interactions between liquid nitrogen and the nanostructured metal powder is important as it can potentially impact the mechanical performance of these materials. In this study, we performed a series of ab initio density functional theory (DFT) computations to examine the interactions of liquid nitrogen and Mg-based matrices and the formation of Mg-nitrides. The diffusion energy barriers of nitrogen in the Mg and/or Mg-Al alloys were systematically quantified by calculating the transition state (TS) for the displacement of nitrogen between two neighboring equivalent positions. The TS calculation results indicate that diffusion of N atoms is much easier than that of N 2  molecule in the Mg matrix. It is predicted that at least ∼0.4 eV is required to overcome the diffusion energy barrier in the Mg matrix. We also quantified the formation energy of Mg nitride in the matrix. The presence of Mg nitride was demonstrated experimentally using transmission electron microscopy (TEM) and electron energy-loss spectroscopy (EELS). In conjunction with the DFT computations and TEM/EELS analysis, we performed analytical calculations for the strain energy introduced during cryomilling to examine the impacts of processing parameters.

[Utilization of feed energy by growing pigs. 3. Energy requirement for the growth and fattening of pigs].

Science.gov (United States)

Hoffmann, L; Schiemann, R; Jentsch, W

1979-02-01

The test series for the investigation of the energy consumption of growing pigs of the breeds large white and improved land race pig as well as cross breeds of the two breeds in a total of 369 metabolism periods (as described in the first two pieces of information of this publication series -- Hoffmann and others, 1977 and Jentsch and Hoffmann, 1977) were statistically analysed for the purpose of the derivation of the energy requirement for maintenance and the partial energy requirement for growth in order to test the possibilities of the factorial analysis for the derivation of energy requirement values of growing pigs. The dependence of the maintenance requirement of growing pigs (investigations in the live weight range of 10 to 40 kg -- see 1st information--were made with boars those in the live weight range of 30 to 120 kg were made with gelded boars, 2nd information) on the live weight can best be characterised by applying a power exponent of 0,61 or 0,62 for the live weight. A definition is offered to be discussed for the energetic maintenance requirement of productive live stock and laboratory animals as a conventional value. The energy requirement values derived from the doubly-factorial statistical analysis show a satisfactory adaptation to the measured values as such concerning energy intake and observed growth performance of the test animals. The conclusion is drawn that the factorial analysis of the energy requirement (maintenance plus partial performances) results in a better estimate of the requirement of growing animals than the assessment according only to live weight and live weight increase without characterising the energy requirement for partial performances. This is important for the further working on and more exact definition of requirement norms.

Perspectives in energy requirements of mankind

International Nuclear Information System (INIS)

Symonds, J.L.

1975-08-01

The growth of energy demand from the nineteenth century to the present and its likely future development are described, for the interested layman, in the context of the changing pattern of resource use. The availability and distribution of the renewable and non-renewable resources of energy, which will provide for the future, show that developed and developing countries will incur supply problems in the decades ahead unless the potential of all energy reserves is tapped. Factors such as the market penetration of new resources and the depletion of resources are outlined. It is pointed out that coal may be used increasingly for some time but that nuclear energy is the only other energy form which is immediately available and which can be utilised commercially. Nuclear energy will be needed even if countries are prepared to cut back to low growth rates in energy use. It is suggested that lower growth rates may well be necessary in the next twenty to thirty years, since it takes this time to bring new alternative technologies into commercial use, and a further similar period will be required to achieve significant resource substitution. (author)

Implementation of Energy Code Controls Requirements in New Commercial Buildings

Energy Technology Data Exchange (ETDEWEB)

Rosenberg, Michael I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hart, Philip R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hatten, Mike [Solarc Energy Group, LLC, Seattle, WA (United States); Jones, Dennis [Group 14 Engineering, Inc., Denver, CO (United States); Cooper, Matthew [Group 14 Engineering, Inc., Denver, CO (United States)

2017-03-24

Most state energy codes in the United States are based on one of two national model codes; ANSI/ASHRAE/IES 90.1 (Standard 90.1) or the International Code Council (ICC) International Energy Conservation Code (IECC). Since 2004, covering the last four cycles of Standard 90.1 updates, about 30% of all new requirements have been related to building controls. These requirements can be difficult to implement and verification is beyond the expertise of most building code officials, yet the assumption in studies that measure the savings from energy codes is that they are implemented and working correctly. The objective of the current research is to evaluate the degree to which high impact controls requirements included in commercial energy codes are properly designed, commissioned and implemented in new buildings. This study also evaluates the degree to which these control requirements are realizing their savings potential. This was done using a three-step process. The first step involved interviewing commissioning agents to get a better understanding of their activities as they relate to energy code required controls measures. The second involved field audits of a sample of commercial buildings to determine whether the code required control measures are being designed, commissioned and correctly implemented and functioning in new buildings. The third step includes compilation and analysis of the information gather during the first two steps. Information gathered during these activities could be valuable to code developers, energy planners, designers, building owners, and building officials.

Sub-ambient carbon dioxide adsorption properties of nitrogen doped graphene

Energy Technology Data Exchange (ETDEWEB)

Tamilarasan, P.; Ramaprabhu, Sundara, E-mail: ramp@iitm.ac.in [Alternative Energy and Nanotechnology Laboratory (AENL), Nano Functional Materials Technology Centre (NFMTC), Department of Physics, Indian Institute of Technology Madras, Chennai 600036 (India)

2015-04-14

Carbon dioxide adsorption on carbon surface can be enhanced by doping the surface with heterogeneous atoms, which can increase local surface affinity. This study presents the carbon dioxide adsorption properties of nitrogen doped graphene at low pressures (<100 kPa). Graphene was exposed to nitrogen plasma, which dopes nitrogen atoms into carbon hexagonal lattice, mainly in pyridinic and pyrrolic forms. It is found that nitrogen doping significantly improves the CO{sub 2} adsorption capacity at all temperatures, due to the enrichment of local Lewis basic sites. In general, isotherm and thermodynamic parameters suggest that doped nitrogen sites have nearly same adsorption energy of surface defects and residual functional groups. The isosteric heat of adsorption remains in physisorption range, which falls with surface coverage, suggesting the distribution of magnitude of adsorption energy. The absolute values of isosteric heat and entropy of adsorption are slightly increased upon nitrogen doping.

Energy requirements for new buildings in Finland

Energy Technology Data Exchange (ETDEWEB)

Airaksinen, M., Email: miimu.airaksinen@vtt.fi

2012-06-15

Buildings account for circa 40% of the total energy use in Europe [1] and for about 36% of the EU's total CO{sub 2} emissions [2], including the existing energy conservation in buildings [3]. Key features of the Finnish energy policy are improved energy efficiency and increased use of renewable energy sources. To achieve a sustainable shift in the energy system, a target set by the authorities, both energy savings and increased use of low-pollution energy sources are therefore priority areas. Building low-energy buildings is in accordance with the declared national aim of reducing energy use and thus reducing CO{sub 2} emissions. The main motivation in renewing building codes for new buildings was to build more energy efficiently, encourage the use the most efficient energy sources and to enhance the use of renewable energy sources. In addition the aim was to give more freedom to fi nd the real optimal solutions for energy efficiency by optimising all aspects including the building architecture and different systems with demand controls. However, in order to ensure the good quality of buildings certain minimum requirements for structure U-values are given. (orig.)

Modeling continuous cultures of microalgae colimited by nitrogen and phosphorus.

Science.gov (United States)

Bougaran, Gaël; Bernard, Olivier; Sciandra, Antoine

2010-08-07

It is well documented that the combination of low nitrogen and phosphorus resources can lead to situations where colimitation of phytoplankton growth arises, yet the underlying mechanisms are not fully understood. Here, we propose a Droop-based model built on the idea that colimitation by nitrogen and phosphorus arises from the uptake of nitrogen. Indeed, since N-porters are active systems, they require energy that could be related to the phosphorus status of the cell. Therefore, we assumed that N uptake is enhanced by the P quota. Our model also accounts for the biological observations that uptake of a nutrient can be down-regulated by its own internal quota, and succeeds in describing the strong contrast for the non-limiting quotas under N-limited and P-limited conditions that was observed on continuous cultures with Selenastrum minutum and with Isochrysis affinis galbana. Our analysis suggests that, regarding the colimitation concept, N and P would be better considered as biochemically dependent rather than biochemically independent nutrients. Copyright 2010 Elsevier Ltd. All rights reserved.

Application of the new environment requirements for SC Turceni power compound and their influence on the electric energy cost

International Nuclear Information System (INIS)

Motocu, Marian; Banica, Valerica

2006-01-01

The power sector has a strategic importance. The lasting development strategy of the power sector includes long terms objectives, which represent the national economy requests relating to the resources, safety and energy efficiency assurance, the renewable resources use and the environmental protection. Nowadays, the humanity is confronting three significant challenges: economic decrease, energy and resources consumption and environment preservation. Under the specific circumstances of the power sector, there are necessary investments which imply important financial efforts. The conclusion of the negotiations relating to Chapter no.22 - Environment - and the alignment to European legislation imply special duties for the industrial and power sector, duties that can be carried out only by making use of performing techniques. The European Directive for large combustion plants -2001/80/EC- is intended to improve the air quality in the European Union countries, that is to protect against the health risks due to the air pollution. The large combustion plants contribute considerably to the sulfur dioxides and nitrogen oxides emissions, and that's why it is necessary for the large combustion plants to comply with the requirements according to the best available techniques phase. The choice of the best techniques available for the large combustion plants depends mainly on the following factors: - the polluting agent (sulphur oxides, nitrogen oxides and dust) - plant type - fuel type - combustion technology. The use of the best available techniques makes possible the combustion of inferior coals, permitting the power plants to comply with the European Environment Regulations. These regulations were established to prevent, and where it is not possible, to reduce the emissions and their impact on the environment. According with the plant of implementing the 2001/80/EC Directive, S.C. Turceni Power Compound S.A. obtained as a deadline for the transition period, the date of

Threshold stoichiometry for beam induced nitrogen depletion of SiN

International Nuclear Information System (INIS)

Timmers, H.; Weijers, T.D.M.; Elliman, R.G.; Uribasterra, J.; Whitlow, H.J.; Sarwe, E.-L.

2002-01-01

Measurements of the stoichiometry of silicon nitride films as a function of the number of incident ions using heavy ion elastic recoil detection (ERD) show that beam-induced nitrogen depletion depends on the projectile species, the beam energy, and the initial stoichiometry. A threshold stoichiometry exists in the range 1.3>N/Si≥1, below which the films are stable against nitrogen depletion. Above this threshold, depletion is essentially linear with incident fluence. The depletion rate correlates non-linearly with the electronic energy loss of the projectile ion in the film. Sufficiently long exposure of nitrogen-rich films renders the mechanism, which prevents depletion of nitrogen-poor films, ineffective. Compromising depth-resolution, nitrogen depletion from SiN films during ERD analysis can be reduced significantly by using projectile beams with low atomic numbers

Computing wheat nitrogen requirements from grain yield and protein maps

Science.gov (United States)

Optical protein sensors and mass-flow yield monitors provide the opportunity to continuously measure grain quality and quantity during harvesting. This chapter illustrates how yield monitor and grain protein measurements may provide useful postharvest information for evaluating water or nitrogen (N)...

Brucella, nitrogen and virulence.

Science.gov (United States)

Ronneau, Severin; Moussa, Simon; Barbier, Thibault; Conde-Álvarez, Raquel; Zuniga-Ripa, Amaia; Moriyon, Ignacio; Letesson, Jean-Jacques

2016-08-01

The brucellae are α-Proteobacteria causing brucellosis, an important zoonosis. Although multiplying in endoplasmic reticulum-derived vacuoles, they cause no cell death, suggesting subtle but efficient use of host resources. Brucellae are amino-acid prototrophs able to grow with ammonium or use glutamate as the sole carbon-nitrogen source in vitro. They contain more than twice amino acid/peptide/polyamine uptake genes than the amino-acid auxotroph Legionella pneumophila, which multiplies in a similar vacuole, suggesting a different nutritional strategy. During these two last decades, many mutants of key actors in nitrogen metabolism (transporters, enzymes, regulators, etc.) have been described to be essential for full virulence of brucellae. Here, we review the genomic and experimental data on Brucella nitrogen metabolism and its connection with virulence. An analysis of various aspects of this metabolism (transport, assimilation, biosynthesis, catabolism, respiration and regulation) has highlighted differences and similarities in nitrogen metabolism with other α-Proteobacteria. Together, these data suggest that, during their intracellular life cycle, the brucellae use various nitrogen sources for biosynthesis, catabolism and respiration following a strategy that requires prototrophy and a tight regulation of nitrogen use.

Changes of the electronic structure of the atoms of nitrogen in nitrogen-doped multiwalled carbon nanotubes under the influence of pulsed ion radiation

Energy Technology Data Exchange (ETDEWEB)

Korusenko, P.M., E-mail: korusenko@obisp.oscsbras.ru [Omsk Scientific Centre, Siberian Branch, Russian Academy of Sciences, Karl Marx Avenue, 15, Omsk 644024 (Russian Federation); Bolotov, V.V.; Nesov, S.N.; Povoroznyuk, S.N. [Omsk Scientific Centre, Siberian Branch, Russian Academy of Sciences, Karl Marx Avenue, 15, Omsk 644024 (Russian Federation); Khailov, I.P. [Tomsk Polytechnic University, Lenin Ave. 2a, Tomsk 634028 (Russian Federation)

2015-09-01

With the use of X-ray photoelectron spectroscopy (XPS) there have been investigated the changes of the chemical state of nitrogen atoms in the structure of nitrogen-doped multiwalled carbon nanotubes (CN{sub x}-MWCNTs) resulting from the impact of pulsed ion beam at various parameters of the beam (energy density, number of pulses). It has been established that irradiation with the pulsed ion beam leads to a reduction of the total amount of nitrogen in CN{sub x} nanotubes. It has been shown that a single pulse irradiation of ion beam at the energy densities of 0.5, 1, 1.5 J/cm{sup 2} leads to restructuring of the nitrogen from pyridinic and pyrrolic configuration to graphitic state. Complete removal of nitrogen (pyridinic, pyrrolic, graphitic) embedded in the structure of the walls of CN{sub x} nanotubes occurs at ten pulses and 1.5 J/cm{sup 2}.

Field Demonstration of a Membrane Process to Separate Nitrogen from Natural Gas

Energy Technology Data Exchange (ETDEWEB)

Kaaeid Lokhandwala

2005-12-22

The original proposal described the construction and operation of a 1 MMscfd treatment system to be operated at a Butcher Energy gas field in Ohio. The gas produced at this field contained 17% nitrogen. During pre-commissioning of the project, a series of well tests showed that the amount of gas in the field was significantly smaller than expected and that the nitrogen content of the wells was very high (25 to 30%). After evaluating the revised cost of the project, Butcher Energy decided that the plant would not be economical and withdrew from the project. Since that time, Membrane Technology and Research, Inc. (MTR) has signed a marketing and sales partnership with ABB Lummus Global, a large multinational corporation. MTR will be working with the company's Randall Gas Technology Group, a supplier of equipment and processing technology to the natural gas industry. Randall's engineering group first found a new site for the project at a North Texas Exploration (NTE) gas processing plant. The plant produced about 1 MMscfd of gas containing 24% nitrogen. The membrane unit was built to bring this gas to 4% nitrogen for delivery to the pipeline. The membrane skid was built by ABB. NTE ordered the required compressor and MTR made the membrane modules for a December 2004 delivery. However, the gas supply was not steady enough for field testing, and MTR/ABB have now located other sites for field testing and commercial development.

Field Demonstration of a Membrane Process to Separate Nitrogen from Natural Gas

Energy Technology Data Exchange (ETDEWEB)

Kaaeid Lokhandwala

2005-12-15

The original proposal described the construction and operation of a 1 MMscfd treatment system to be operated at a Butcher Energy gas field in Ohio. The gas produced at this field contained 17% nitrogen. During pre-commissioning of the project, a series of well tests showed that the amount of gas in the field was significantly smaller than expected and that the nitrogen content of the wells was very high (25 to 30%). After evaluating the revised cost of the project, Butcher Energy decided that the plant would not be economical and withdrew from the project. Since that time, Membrane Technology and Research, Inc. (MTR) has signed a marketing and sales partnership with ABB Lummus Global, a large multinational corporation. MTR is now working with the company's Randall Gas Technology Group, a supplier of equipment and processing technology to the natural gas industry. Randall's engineering group first found a new site for the project at a North Texas Exploration (NTE) gas processing plant. The plant produced about 1 MMscfd of gas containing 24% nitrogen. The membrane unit was built to bring this gas to 4% nitrogen for delivery to the pipeline. The membrane skid was built by ABB. NTE ordered the required compressor and MTR made the membrane modules for a December 2004 delivery. However, the gas supply was not steady enough for field testing, and MTR/ABB have now located other sites for field testing and commercial development.

Energy productivity, fertilization rate and profitability of wheat production after various predecessors II.Profitability of wheat production

Directory of Open Access Journals (Sweden)

Z. Uhr

2016-03-01

Full Text Available Abstract. In the course of our study on the adaptation of modern genotypes common winter wheat (Triticum aestivum to the requirements of sustainable agriculture data were received concerning the influence of the predecessor and nitrogen fertilizer rate on energy efficiency and recyclable nitrogen fertilization and profitability of productivity.We share these data with the scientific community, as they are up-to-date and informative in both theoretical and practical aspects. The analyses are based on data from field experiments fertilizer derived after predecessor cereals – regular crop of sorghum, millet, maize and legumes after predecessor - separate sowing of chickpeas. Energy efficiency of nitrogen fertilization was calculated as the ratio between the energy supplied in the additional grain yield and energy input in the form of fertilizers. Refundable efficiency of nitrogen fertilization is the additional amount of nitrogen accumulated in the grain, with respect to the applied nitrogen fertilization. Economic profitability of production is evaluated by coefficient R = P/Ra (ratio of benefits/costs. The results show that energy efficiency and recyclable nitrogen fertilization are on average five times higher after cereal than after legumes predecessor, and decreased with increasing the fertilizer rate, the decrease was statistically significant only for the first item (exponent. Profitability ratio of production after the introduction of legumes predecessor in crop rotation increases by an average of 42% and retains maximum values of fertilization levels 0.06, 0.12 and 0.18 t/ha nitrogen. Profitability of wheat production using pre-legumes crop is not determined by the parameters nitrogen fertilizer rate and energy efficiency of nitrogen fertilization and refundable efficiency of nitrogen fertilization.

Investment requirements in the energy sector and their financing

Energy Technology Data Exchange (ETDEWEB)

Diel, R; Radtke, G; Stoesel, R

1981-06-01

The present research study illustrates the required volume of investment in the energy sector during the next two decades while referring explicitly to the availability of financial resources. The data for the respective primary energy sources and electric power production relate to the Federal Republic of Germany; still, as far as figures were available, the energy situation of the Western World is taken into account. Starting from the premise that energy needs will continue to grow - albeit at a slower rate -, future investment activity will have to depart from past trends, with their more or less evenly spread recourse to all available primary energy sources, to a substantial reliance on nuclear energy, coal and natural gas as against oil. In addition to the higher capital requirements due to the restructuring of the energy supply, future investment will be characterized by particularly capital-intensive projects and, in addition, by the fact that expensive development schemes must be vigorously pursued. This applies not only to coal gasification and liquifaction but also to regenerative energy sources.

Nitrogen implantation in steel with an impulsive ion implanter

International Nuclear Information System (INIS)

Feugeas, J.N.; Gonzalez, C.O.; Hermida, J.; Nieto, M.; Peyronel, M.F.; Sanchez, G.

1990-01-01

This work describes the results of steel implantation with nitrogen, with a pulsed accelerator which provides a continuous ion energy spectrum giving a uniform profile of nitrogen without changing its operative conditions. (Author)

Changing Energy Requirements in the Mediterranean Under Changing Climatic Conditions

Directory of Open Access Journals (Sweden)

George Demosthenous

2009-09-01

Full Text Available This study investigates the impacts of climate change on energy requirements in the Mediterranean. Energy requirements, especially for space heating and cooling, are closely linked to several weather variables, mainly air temperature. The analysis is based on daily temperature outputs from several regional climate models run at a resolution of 25 km × 25 km in the framework of EU project ENSEMBLES using the A1B emissions scenario. The impacts of changes in temperature on energy requirements are investigated using the concept of degree days, defined as the difference of mean air temperature from a base temperature. Base temperature should be chosen to coincide with the minimum energy consumption. In this way, changes in heating and cooling requirements between the reference and the future period are calculated and areas about to undergo large changes identified. These changes are calculated between a 30-year reference period 1961–1990 and a near future period 2021–2050 taking the ensemble mean of all regional climate models. The near-term future has been chosen instead of the frequently used end-of-the-century period to assist policy makers in their planning. In general, a decrease in energy requirements is projected under future milder winters and an increase under hotter summers.

The Role of Photovoltaics in Energy Requirements in Pakistan

International Nuclear Information System (INIS)

Shah, I.A.; Haq, N.U.; Nasir, H.

2011-01-01

In this review article global energy issue is discussed with specific reference to Pakistan. The energy consumption and supply from different sources like oil, gas, electricity, nuclear power, bio gas and especially from renewables is taken into account. Also discussed some suggestions for the energy requirements. Focus is given to the production of renewable energy sources like technology of photovoltaics in which solar power is converted into electricity. Solar cell is discussed including its two basic types inorganic solar cell and organic solar cell, its way of functioning, process of fabrication etc is also discussed. Organic or polymeric solar cell is discussed in detail. keeping in view the financial condition and requirement of energy for our country suggestions are given for low cost and simple processing of organic solar cells. It is also suggested that availability of all the materials required for the development of organic solar cells should be guaranteed. Interest should be developed at the university and other research organization level of Pakistan to do work on polymeric solar cells for increasing their efficiencies so that they can be practically utilized. (author)

Whole-body protein turnover and energy expenditure in post-viral hepatocirrhotic patients. A study using multiple stable isotope tracers to estimate protein and energy requirements and the efficacy of a new diet therapy based on Chinese food

International Nuclear Information System (INIS)

Xia, Z.Q.; Dai, T.C.; Luo, W.

1993-01-01

L-[1- 13 C]-leucine and 15 N-glycine doubly-labelled tracer experiments revealed accelerated kinetics of leucine, glycine and whole-body protein in post-viral hepatocirrhotic patients. Together with the results of nitrogen balance measurement, the daily protein requirement of these patients was estimated to be higher than 1.2 g/kg/d. Doubly labelled water experiments and NaH 13 CO 3 experiments revealed that the freely living and basal energy expenditure of post-viral hepatocirrhotic patients was not different from that in normal subjects with comparable physical and mental activities. For those freely living in hospital, the energy requirements is estimated to be 150-160 kJ/kg/d. According to the above results, a therapeutic diet formulation based on Chinese food was designed for the patients which contained 1.5 g/kg/d of protein and 150-160 kJ/kg/d. 60-70% of the dietary protein was of vegetable origin, with a branched chain amino acid/aromatic amino acid ratio slightly but significantly higher than the common hospital diet. Patients with compensated post-viral hepatocirrhosis adapted to the diet rapidly. After two months' therapy, the negative nitrogen balance turned positive along with an increase of body weight and urinary creatinine, indicating and improvement of general nutritional status, probably with accumulation of muscle protein. The diet is relatively cheap, can be easily handled by the patients themselves, and hence is also applicable to outpatients. 54 refs, 8 tabs

ENERGY-REQUIREMENTS FOR MOLT IN THE KESTREL FALCO-TINNUNCULUS

NARCIS (Netherlands)

DIETZ, MW; DAAN, S; MASMAN, D

1992-01-01

We estimated energy requirements for plumage replacement in the kestrel (Falco tinnunculus) by comparing O2 consumption Vo2 and metabolizable energy intake during molt and nonmolt. The energy expenditure for feather synthesis (S) as derived from the regression of basal metabolic rate (BMR) on molt

Numerical Simulation and Analysis on Liquid Nitrogen Spray Heat Exchanger

OpenAIRE

Wenjing Ding; Weiwei Shan; Zijuan; Wang; Chao He

2017-01-01

Liquid spray heat exchanger is the critical equipment of temperature regulating system by gaseous nitrogen which realizes the environment temperature in the range of -180 ℃~+180 ℃. Liquid nitrogen is atomized into smaller liquid drops through liquid nitrogen sprayer and then contacts with gaseous nitrogen to be cooled. By adjusting the pressure of liquid nitrogen and gaseous nitrogen, the flowrate of liquid nitrogen is changed to realize the required outlet temperature of heat exchanger. The ...

Analysis of the energy requirement for household consumption

NARCIS (Netherlands)

Vringer, Kees

2005-01-01

Humans in households use energy for their activities. This use is both direct, for example electricity and natural gas, but also indirect, for the production, transport and trade of other goods and services. The main objective of this thesis is to gain insight into the energy requirement associated

Biological nitrogen fixation in relation to energy forest production. Progress report, 1978-1980

Energy Technology Data Exchange (ETDEWEB)

Clarholm, M; Granhall, U

1981-01-01

Different pasture legumes, Alnus incana and Myrica gale have been tested in pot experiments and field trials with respect to their use as biological N-fertilizers in relation to energy forest production. So far experiments have been mainly concerned with their establishemnts as on intercrop with Galix at a mire site with ombrotrophic peat and in two clayish arable soils. Laboratory experiments have been made to determine optimal conditions for growth and nitrogen fixation of wild and Alaska lupines in relation to varous soil amendments in the form of lime, ash, NPKMo, and Fe. A pilot experiment of the terrelations between willows and grey alder growing together in peat has been started at Uppsala.

Energy saving processes for nitrogen removal in organic wastewater from food processing industries in Thailand.

Science.gov (United States)

Johansen, N H; Suksawad, N; Balslev, P

2004-01-01

Nitrogen removal from organic wastewater is becoming a demand in developed communities. The use of nitrite as intermediate in the treatment of wastewater has been largely ignored, but is actually a relevant energy saving process compared to conventional nitrification/denitrification using nitrate as intermediate. Full-scale results and pilot-scale results using this process are presented. The process needs some additional process considerations and process control to be utilized. Especially under tropical conditions the nitritation process will round easily, and it must be expected that many AS treatment plants in the food industry already produce NO2-N. This uncontrolled nitrogen conversion can be the main cause for sludge bulking problems. It is expected that sludge bulking problems in many cases can be solved just by changing the process control in order to run a more consequent nitritation. Theoretically this process will decrease the oxygen consumption for oxidation by 25% and the use of carbon source for the reduction will be decreased by 40% compared to the conventional process.

Energy transfers between N_2(A"3Σ) nitrogen metastable molecules and oxygen atoms and molecules

International Nuclear Information System (INIS)

De Souza, Antonio Rogerio

1985-01-01

This research thesis aims at determining reaction coefficients for energy transfers between nitrogen in its metastable status and oxygen atoms and molecules, the variation of these coefficients with respect to temperature (mainly in the 200-400 K range), products formed and more particularly branching rates of O("1S) oxygen and of NO_2. Reaction coefficients are experimentally determined by using the technique of post-discharge in flow. The experimental set-up is described and the study of the best operating conditions is reported. In the next part, the author reports the study of the energy transfer between nitrogen in its metastable status N_2(A) and oxygen molecules. Reaction coefficients are determined for the first three vibrational levels. The author then reports the study of the transfer of N_2(A) molecules on oxygen atoms in their fundamental status. Reactions coefficients and their variations are determined for the three first vibrational levels. The author describes the dissociation method and the method of detection of atomic oxygen. A kinetic model is proposed for the analysis of formed products during a post-discharge in flow, and the branching rate for the formation of O("1S) oxygen between 190 and 365 K is determined. The author finally discusses publications on the role of these reactions in the interpretation of some atmospheric phenomena

Comparison of energy performance requirements levels

DEFF Research Database (Denmark)

Spiekman, Marleen; Thomsen, Kirsten Engelund; Rose, Jørgen

This summary report provides a synthesis of the work within the EU SAVE project ASIEPI on developing a method to compare the energy performance (EP) requirement levels among the countries of Europe. Comparing EP requirement levels constitutes a major challenge. From the comparison of for instance...... the present Dutch requirement level (EPC) of 0,8 with the present Flemish level of E80, it can easily be seen that direct comparison is not possible. The conclusions and recommendations of the study are presented in part A. These constitute the most important result of the project. Part B gives an overview...... of all other project material related to that topic, which allows to easily identify the most pertinent information. Part C lists the project partners and sponsors....

Carbon and nitrogen stoichiometry across stream ecosystems

Science.gov (United States)

Wymore, A.; Kaushal, S.; McDowell, W. H.; Kortelainen, P.; Bernhardt, E. S.; Johnes, P.; Dodds, W. K.; Johnson, S.; Brookshire, J.; Spencer, R.; Rodriguez-Cardona, B.; Helton, A. M.; Barnes, R.; Argerich, A.; Haq, S.; Sullivan, P. L.; López-Lloreda, C.; Coble, A. A.; Daley, M.

2017-12-01

Anthropogenic activities are altering carbon and nitrogen concentrations in surface waters globally. The stoichiometry of carbon and nitrogen regulates important watershed biogeochemical cycles; however, controls on carbon and nitrogen ratios in aquatic environments are poorly understood. Here we use a multi-biome and global dataset (tropics to Arctic) of stream water chemistry to assess relationships between dissolved organic carbon (DOC) and nitrate, ammonium and dissolved organic nitrogen (DON), providing a new conceptual framework to consider interactions between DOC and the multiple forms of dissolved nitrogen. We found that across streams the total dissolved nitrogen (TDN) pool is comprised of very little ammonium and as DOC concentrations increase the TDN pool shifts from nitrate to DON dominated. This suggests that in high DOC systems, DON serves as the primary source of nitrogen. At the global scale, DOC and DON are positively correlated (r2 = 0.67) and the average C: N ratio of dissolved organic matter (molar ratio of DOC: DON) across our data set is approximately 31. At the biome and smaller regional scale the relationship between DOC and DON is highly variable (r2 = 0.07 - 0.56) with the strongest relationships found in streams draining the mixed temperate forests of the northeastern United States. DOC: DON relationships also display spatial and temporal variability including latitudinal and seasonal trends, and interactions with land-use. DOC: DON ratios correlated positively with gradients of energy versus nutrient limitation pointing to the ecological role (energy source versus nutrient source) that DON plays with stream ecosystems. Contrary to previous findings we found consistently weak relationships between DON and nitrate which may reflect DON's duality as an energy or nutrient source. Collectively these analyses demonstrate how gradients of DOC drive compositional changes in the TDN pool and reveal a high degree of variability in the C: N ratio

Synthesis of nitrogen-doped porous carbon nanofibers as an efficient electrode material for supercapacitors.

Science.gov (United States)

Chen, Li-Feng; Zhang, Xu-Dong; Liang, Hai-Wei; Kong, Mingguang; Guan, Qing-Fang; Chen, Ping; Wu, Zhen-Yu; Yu, Shu-Hong

2012-08-28

Supercapacitors (also known as ultracapacitors) are considered to be the most promising approach to meet the pressing requirements of energy storage. Supercapacitive electrode materials, which are closely related to the high-efficiency storage of energy, have provoked more interest. Herein, we present a high-capacity supercapacitor material based on the nitrogen-doped porous carbon nanofibers synthesized by carbonization of macroscopic-scale carbonaceous nanofibers (CNFs) coated with polypyrrole (CNFs@polypyrrole) at an appropriate temperature. The composite nanofibers exhibit a reversible specific capacitance of 202.0 F g(-1) at the current density of 1.0 A g(-1) in 6.0 mol L(-1) aqueous KOH electrolyte, meanwhile maintaining a high-class capacitance retention capability and a maximum power density of 89.57 kW kg(-1). This kind of nitrogen-doped carbon nanofiber represents an alternative promising candidate for an efficient electrode material for supercapacitors.

46 CFR 151.50-36 - Argon or nitrogen.

Science.gov (United States)

2010-10-01

... 46 Shipping 5 2010-10-01 2010-10-01 false Argon or nitrogen. 151.50-36 Section 151.50-36 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-36 Argon or nitrogen. (a) A cargo tank that contains argon or nitrogen and that has a maximum allowable working pressure of 172 kPa (25...

Structure requirements for magnetic energy storage devices

International Nuclear Information System (INIS)

Eyssa, Y.M.; Huang, X.

1993-01-01

Large variety of large and small magnetic energy storage systems have been designed and analyzed in the last 20 years. Cryoresistive and superconductive energy storage (SMES) magnets have been considered for applications such as load leveling for electric utilities, pulsed storage for electromagnetic launchers and accelerator devices, and space borne superconductive energy storage systems. Large SMES are supported by a combination of cold and warm structure while small SMES are supported only by cold structure. In this article we provide analytical and numerical tools to estimate the structure requirements as function of the stored energy and configuration. Large and small solenoidal and toroidal geometries are used. Considerations for both warm and cold structure are discussed. Latest design concepts for both large and small units are included. (orig.)

Reactive nitrogen in the environment and its effect on climate change

NARCIS (Netherlands)

Erisman, J.W.; Galloway, J.N.; Seitzinger, S.; Bleeker, A.; Butterbach-Bahl, K.

2011-01-01

Humans have doubled levels of reactive nitrogen in circulation, largely as a result of fertilizer application and fossil fuel burning. This massive alteration of the nitrogen cycle affects climate, food security, energy security, human health and ecosystem services. Our estimates show that nitrogen

Nitrogen cycling in an integrated biomass for energy system

International Nuclear Information System (INIS)

Moorhead, K.K.

1986-01-01

A series of experiments was conducted to evaluate N cycling in three components of an integrated biomass for energy system, i.e. water hyacinth production, anaerobic digestion in hyacinth biomass, and recycling of digester effluent and sludge. Plants assimilated 50 to 90% of added N in hyacinth production systems. Up to 28% of the total plant N was contained in hyacinth detritus. Nitrogen loading as plant detritus into hyacinth ponds was 92 to 148 kg N ha -1 yr -1 . Net mineralization of plant organic 15 N during anaerobic digestion was 35 and 70% for water hyacinth plants with low and high N content, respectively. Approximately 20% of the 15 N was recovered in the digested sludge while the remaining 15 N was recovered in the effluent. Water hyacinth growth in digester effluents was affected by electrical conductivity and 15 NH 4 + -N concentration. Addition of water hyacinth biomass to soil resulted in decomposition of 39 to 50% of added C for fresh plant biomass and 19 to 23% of added C for digested biomass sludge. Only 8% of added 15 N in digested sludges was mineralized to 15 NO 3 - -N despite differences in initial N content. In contrast, 3 and 33% of added 15 N in fresh biomass with low and high N content, respectively, was recovered as 15 NO 3 - -N. Total 15 N recovery after anaerobic digestion ranged from 70 to 100% of the initial plant biomass 15 N. Total N recovery by sludge and effluent recycling in the integrated biomass for energy system was 48 to 60% of the initial plant biomass 15 N

Energy and nitrogen balances in 24 severely burned patients receiving 4 isocaloric diets of about 10 MJ/m2/day (2392 Kcalories/m2/day).

Science.gov (United States)

Serog, P; Baigts, F; Apfelbaum, M; Guilbaud, J; Chauvin, B; Pecqueur, M L

1983-07-01

Twenty-four subjects with burns ranging from 25-70 per cent received for 12 days exclusively per os a series of 4 isocaloric diets of about 4000 Kcal--'normal', or hyperproteic, or hyperlipidic, or hyperglucidic according to a randomized schedule. Oxygen consumptions were measured at the end of each diet and nitrogen balance was determined every day. Though patients were not massively overfed there remained a positive energy gap. The nitrogen balance was found to be equilibrated on the whole but clearly positive with the hyperproteic diet and clearly negative with the hyperlipidic-normoproteic diet. Thus there is no rationale for the huge energy overfeeding classically used.

Maintenance Energy Requirements of Double-Muscled Belgian Blue Beef Cows

OpenAIRE

Fiems, Leo O.; De Boever, Johan L.; Vanacker, José M.; De Campeneere, Sam

2015-01-01

Simple Summary Double-muscled Belgian Blue animals are extremely lean, characterized by a deviant muscle fiber type with more fast-glycolytic fibers, compared to non-double-muscled animals. This fiber type may result in lower maintenance energy requirements. On the other hand, lean meat animals mostly have a higher rate of protein turnover, which requires more energy for maintenance. Therefore, maintenance requirements of Belgian Blue cows were investigated based on a zero body weight gain. T...

The Global Nitrogen Cycle

Science.gov (United States)

Galloway, J. N.

2003-12-01

transfer depended on the reactivity of the emitted material. At the lower extreme of reactivity are the noble gases, neon and argon. Most neon and argon emitted during the degassing of the newly formed Earth is still in the atmosphere, and essentially none has been transferred to the hydrosphere or crust. At the other extreme are carbon and sulfur. Over 99% of the carbon and sulfur emitted during degassing are no longer in the atmosphere, but reside in the hydrosphere or the crust. Nitrogen is intermediate. Of the ˜6×106 TgN in the atmosphere, hydrosphere, and crust, ˜2/3 is in the atmosphere as N2 with most of the remainder in the crust. The atmosphere is a large nitrogen reservoir primarily, because the triple bond of the N2 molecule requires a significant amount of energy to break. In the early atmosphere, the only sources of such energy were solar radiation and electrical discharges.At this point we had an earth with mostly N2 and devoid of life. How did we get to an earth with mostly N2 and teeming with life? First, N2 had to be converted into reactive N (Nr). (The term reactive nitrogen (Nr) includes all biologically active, photochemically reactive, and radiatively active nitrogen compounds in the atmosphere and biosphere of the Earth. Thus, Nr includes inorganic reduced forms of nitrogen (e.g., NH3 and NH4+), inorganic oxidized forms (e.g., NOx, HNO3, N2O, and NO3-), and organic compounds (e.g., urea, amines, and proteins).) The early atmosphere was reducing and had limited NH3. However, NH3 was a necessary ingredient in forming early organic matter. One possibility for NH3 generation was the cycling of seawater through volcanics (Holland, 1984). Under such a process, NH3 could then be released to the atmosphere where, when combined with CH4, H2, H2O, and electrical energy, organic molecules including amino acids could be formed (Miller, 1953). In essence, electrical discharges and UV radiation can convert mixtures of reduced gases into mixtures of organic

A Comprehensive Energy Analysis and Related Carbon Footprint of Dairy Farms, Part 1: Direct Energy Requirements

Directory of Open Access Journals (Sweden)

Giuseppe Todde

2018-02-01

Full Text Available Dairy cattle farms are continuously developing more intensive systems of management which require higher utilization of durable and not-durable inputs. These inputs are responsible of significant direct and indirect fossil energy requirements which are related to remarkable emissions of CO2. This study aims to analyze direct energy requirements and the related carbon footprint of a large population of conventional dairy farms located in the south of Italy. A detailed survey of electricity, diesel and Liquefied Petroleum Gas (LPG consumptions has been carried out among on-farm activities. The results of the analyses showed an annual average fuel consumption of 40 kg per tonne of milk, while electricity accounted for 73 kWh per tonne of milk produced. Expressing the direct energy inputs as primary energy, diesel fuel results the main resource used in on-farm activities, accounting for 72% of the total fossil primary energy requirement, while electricity represents only 27%. Moreover, larger farms were able to use more efficiently the direct energy inputs and reduce the related emissions of carbon dioxide per unit of milk produced, since the milk yield increases with the herd size. The global average farm emissions of carbon dioxide equivalent, due to all direct energy usages, accounted for 156 kg CO2-eq per tonne of Fat and Protein Corrected Milk (FPCM, while farms that raise more than 200 heads emitted 36% less than the average value. In this two-part series, the total energy demand (Part 1 + Part 2 per farm is mainly due to agricultural inputs and fuel consumption, which have the largest quota of the annual requirements for each milk yield class. These results also showed that large size farms held lower CO2-eq emissions when referred to the mass of milk produced.

Interplay of Nitrogen-Atom Inversion and Conformational Inversion in Enantiomerization of 1H-1-Benzazepines.

Science.gov (United States)

Ramig, Keith; Subramaniam, Gopal; Karimi, Sasan; Szalda, David J; Ko, Allen; Lam, Aaron; Li, Jeffrey; Coaderaj, Ani; Cavdar, Leyla; Bogdan, Lukasz; Kwon, Kitae; Greer, Edyta M

2016-04-15

A series of 2,4-disubstituted 1H-1-benzazepines, 2a-d, 4, and 6, were studied, varying both the substituents at C2 and C4 and at the nitrogen atom. The conformational inversion (ring-flip) and nitrogen-atom inversion (N-inversion) energetics were studied by variable-temperature NMR spectroscopy and computations. The steric bulk of the nitrogen-atom substituent was found to affect both the conformation of the azepine ring and the geometry around the nitrogen atom. Also affected were the Gibbs free energy barriers for the ring-flip and the N-inversion. When the nitrogen-atom substituent was alkyl, as in 2a-c, the geometry of the nitrogen atom was nearly planar and the azepine ring was highly puckered; the result was a relatively high-energy barrier to ring-flip and a low barrier to N-inversion. Conversely, when the nitrogen-atom substituent was a hydrogen atom, as in 2d, 4, and 6, the nitrogen atom was significantly pyramidalized and the azepine ring was less puckered; the result here was a relatively high energy barrier to N-inversion and a low barrier to ring-flip. In these N-unsubstituted compounds, it was found computationally that the lowest-energy stereodynamic process was ring-flip coupled with N-inversion, as N-inversion alone had a much higher energy barrier.

Energy Consumption vs. Energy Requirement

Science.gov (United States)

Fan, L. T.; Zhang, Tengyan; Schlup, John R.

2006-01-01

Energy is necessary for any phenomenon to occur or any process to proceed. Nevertheless, energy is never consumed; instead, it is conserved. What is consumed is available energy, or exergy, accompanied by an increase in entropy. Obviously, the terminology, "energy consumption" is indeed a misnomer although it is ubiquitous in the…

Assessing the Social and Environmental Costs of Institution Nitrogen Footprints.

Science.gov (United States)

Compton, Jana E; Leach, Allison M; Castner, Elizabeth A; Galloway, James N

2017-04-01

This article estimates the damage costs associated with the institutional nitrogen (N) footprint and explores how this information could be used to create more sustainable institutions. Potential damages associated with the release of nitrogen oxides (NOx), ammonia (NH 3 ), and nitrous oxide (N 2 O) to air and release of nitrogen to water were estimated using existing values and a cost per unit of nitrogen approach. These damage cost values were then applied to two universities. Annual potential damage costs to human health, agriculture, and natural ecosystems associated with the N footprint of institutions were $11.0 million (2014) at the University of Virginia (UVA) and $3.04 million at the University of New Hampshire (UNH). Costs associated with the release of nitrogen oxides to human health, in particular the use of coal-derived energy, were the largest component of damage at UVA. At UNH the energy N footprint is much lower because of a landfill cogeneration source, and thus the majority of damages were associated with food production. Annual damages associated with release of nitrogen from food production were very similar at the two universities ($1.80 million vs. $1.66 million at UVA and UNH, respectively). These damages also have implications for the extent and scale at which the damages are felt. For example, impacts to human health from energy and transportation are generally larger near the power plants and roads, while impacts from food production can be distant from the campus. Making this information available to institutions and communities can improve their understanding of the damages associated with the different nitrogen forms and sources, and inform decisions about nitrogen reduction strategies.

Synthesis and review: Tackling the nitrogen management challenge: from global to local scales

Science.gov (United States)

Reis, Stefan; Bekunda, Mateete; Howard, Clare M.; Karanja, Nancy; Winiwarter, Wilfried; Yan, Xiaoyuan; Bleeker, Albert; Sutton, Mark A.

2016-12-01

One of the ‘grand challenges’ of this age is the anthropogenic impact exerted on the nitrogen cycle. Issues of concern range from an excess of fixed nitrogen resulting in environmental pressures for some regions, while for other regions insufficient fixed nitrogen affects food security and may lead to health risks. To address these issues, nitrogen needs to be managed in an integrated fashion, at a variety of scales (from global to local). Such management has to be based on a thorough understanding of the sources of reactive nitrogen released into the environment, its deposition and effects. This requires a comprehensive assessment of the key drivers of changes in the nitrogen cycle both spatially, at the field, regional and global scale and over time. In this focus issue, we address the challenges of managing reactive nitrogen in the context of food production and its impacts on human and ecosystem health. In addition, we discuss the scope for and design of management approaches in regions with too much and too little nitrogen. This focus issue includes several contributions from authors who participated at the N2013 conference in Kampala in November 2013, where delegates compiled and agreed upon the ‘Kampala Statement-for-Action on Reactive Nitrogen in Africa and Globally’. These contributions further underline scientifically the claims of the ‘Kampala Statement’, that simultaneously reducing pollution and increasing nitrogen available in the food system, by improved nitrogen management offers win-wins for environment, health and food security in both developing and developed economies. The specific messages conveyed in the Kampala Statement focus on improving nitrogen management (I), including the reduction of nitrogen losses from agriculture, industry, transport and energy sectors, as well as improving waste treatment and informing individuals and institutions (II). Highlighting the need for innovation and increased awareness among stakeholders (III

Spatial distribution of fluorescent light emitted from neon and nitrogen excited by low energy electron beams

International Nuclear Information System (INIS)

Morozov, A.; Kruecken, R.; Ulrich, A.; Wieser, J.

2006-01-01

Side-view intensity profiles of fluorescent light were measured for neon and nitrogen excited with 12 keV electron beams at gas pressures from 250 to 1400 hPa. The intensity profiles were compared with theoretical profiles calculated using the CASINO program which performs Monte Carlo simulations of electron scattering. It was assumed that the spatial distribution of fluorescent intensity is directly proportional to the spatial distribution of energy loss by primary electrons. The comparison shows good correlation of experimental data and the results of numeric simulations

Nitrogen recycling from fuel-extracted algal biomass: residuals as the sole nitrogen source for culturing Scenedesmus acutus.

Science.gov (United States)

Gu, Huiya; Nagle, Nick; Pienkos, Philip T; Posewitz, Matthew C

2015-05-01

In this study, the reuse of nitrogen from fuel-extracted algal residues was investigated. The alga Scenedesmus acutus was found to be able to assimilate nitrogen contained in amino acids, yeast extracts, and proteinaceous alga residuals. Moreover, these alternative nitrogen resources could replace nitrate in culturing media. The ability of S. acutus to utilize the nitrogen remaining in processed algal biomass was unique among the promising biofuel strains tested. This alga was leveraged in a recycling approach where nitrogen is recovered from algal biomass residuals that remain after lipids are extracted and carbohydrates are fermented to ethanol. The protein-rich residuals not only provided an effective nitrogen resource, but also contributed to a carbon "heterotrophic boost" in subsequent culturing, improving overall biomass and lipid yields relative to the control medium with only nitrate. Prior treatment of the algal residues with Diaion HP20 resin was required to remove compounds inhibitory to algal growth. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nitrogen in rock: Occurrences and biogeochemical implications

Science.gov (United States)

Holloway, J.M.; Dahlgren, R.A.

2002-01-01

There is a growing interest in the role of bedrock in global nitrogen cycling and potential for increased ecosystem sensitivity to human impacts in terrains with elevated background nitrogen concentrations. Nitrogen-bearing rocks are globally distributed and comprise a potentially large pool of nitrogen in nutrient cycling that is frequently neglected because of a lack of routine analytical methods for quantification. Nitrogen in rock originates as organically bound nitrogen associated with sediment, or in thermal waters representing a mixture of sedimentary, mantle, and meteoric sources of nitrogen. Rock nitrogen concentrations range from trace levels (>200 mg N kg -1) in granites to ecologically significant concentrations exceeding 1000 mg N kg -1 in some sedimentary and metasedimentary rocks. Nitrate deposits accumulated in arid and semi-arid regions are also a large potential pool. Nitrogen in rock has a potentially significant impact on localized nitrogen cycles. Elevated nitrogen concentrations in water and soil have been attributed to weathering of bedrock nitrogen. In some environments, nitrogen released from bedrock may contribute to nitrogen saturation of terrestrial ecosystems (more nitrogen available than required by biota). Nitrogen saturation results in leaching of nitrate to surface and groundwaters, and, where soils are formed from ammonium-rich bedrock, the oxidation of ammonium to nitrate may result in soil acidification, inhibiting revegetation in certain ecosystems. Collectively, studies presented in this article reveal that geologic nitrogen may be a large and reactive pool with potential for amplification of human impacts on nitrogen cycling in terrestrial and aquatic ecosystems.

Production mechanism of atomic nitrogen in atmospheric pressure pulsed corona discharge measured using two-photon absorption laser-induced fluorescence

International Nuclear Information System (INIS)

Teramoto, Yoshiyuki; Ono, Ryo; Oda, Tetsuji

2012-01-01

To study the production mechanism of atomic nitrogen, the temporal profile and spatial distribution of atomic nitrogen are measured in atmospheric pressure pulsed positive corona discharge using two-photon absorption laser-induced fluorescence. The absolute atomic nitrogen density in the streamer filaments is estimated from decay rate of atomic nitrogen in N 2 discharge. The results indicate that the absolute atomic nitrogen density is approximately constant against discharge energy. When the discharge voltage is 21.5 kV, production yield of atomic nitrogen produced by an N 2 discharge pulse is estimated to be 2.9 - 9.8 × 10 13 atoms and the energy efficiency of atomic nitrogen production is estimated to be about 1.8 - 6.1 × 10 16 atoms/J. The energy efficiency of atomic nitrogen production in N 2 discharge is constant against the discharge energy, while that in N 2 /O 2 discharge increases with discharge energy. In the N 2 /O 2 discharge, two-step process of N 2 dissociation plays significant role for atomic nitrogen production.

Utilization of urea/molasses liquid feed as a major source of nitrogen and energy for lactating cows

International Nuclear Information System (INIS)

Ranjhan, S.K.; Krishna Mohan, D.V.G.; Pathak, N.N.

1976-01-01

Experiments were conducted in which urea/molasses liquid feed along with a limited amount of intact protein and cereal forage was fed to lactating cows, and compared with another group receiving conventional concentrate and roughage-based rations. Voluntary consumption of liquid feed by cows was satisfactory. There was no significant difference in the milk yield between the two groups. The higher consumption of metabolizable energy and digestible crude protein by experimental cows from liquid feed was not reflected in their milk yields or body weights. Various other parameters such as digestibilities of nutrients, efficiency of energy and nitrogen utilization for milk production and N-balance have been presented in cows fed urea/molasses liquid diets and conventional diets. (author)

The water footprint of energy consumption: an assessment of water requirements of primary energy carriers

NARCIS (Netherlands)

Gerbens-Leenes, P.W.; Hoekstra, A.Y.; Van der Meer, T.H.

2007-01-01

Gerbens-Leenes, P.W., Hoekstra, A.Y., Van der Meer, T.H., 2007. The water footprint of energy consumption: an assessment of water requirements of primary energy carriers. In: proceedings ‘First World Water Sustainability-Renewable Energy Congress and Exhibition’. 25-28 November 2007, Maastricht, the

Required Assets for a Nuclear Energy Applied R&D Program

Energy Technology Data Exchange (ETDEWEB)

Harold F. McFarlane; Craig L. Jacobson

2009-03-01

This report is one of a set of three documents that have collectively identified and recommended research and development capabilities that will be required to advance nuclear energy in the next 20 to 50 years. The first report, Nuclear Energy for the Future: Required Research and Development Capabilities—An Industry Perspective, was produced by Battelle Memorial Institute at the request of the Assistant Secretary of Nuclear Energy. That report, drawn from input by industry, academia, and Department of Energy laboratories, can be found in Appendix 5.1. This Idaho National Laboratory report maps the nuclear-specific capabilities from the Battelle report onto facility requirements, identifying options from the set of national laboratory, university, industry, and international facilities. It also identifies significant gaps in the required facility capabilities. The third document, Executive Recommendations for Nuclear R&D Capabilities, is a letter report containing a set of recommendations made by a team of senior executives representing nuclear vendors, utilities, academia, and the national laboratories (at Battelle’s request). That third report can be found in Appendix 5.2. The three reports should be considered as set in order to have a more complete picture. The basis of this report was drawn from three sources: previous Department of Energy reports, workshops and committee meetings, and expert opinion. The facilities discussed were winnowed from several hundred facilities that had previously been catalogued and several additional facilities that had been overlooked in past exercises. The scope of this report is limited to commercial nuclear energy and those things the federal government, or more specifically the Office of Nuclear Energy, should do to support its expanded deployment in order to increase energy security and reduce carbon emissions. In the context of this report, capabilities mean innovative, well-structured research and development programs

Characterization of nitrogen-ion-implanted aluminium

International Nuclear Information System (INIS)

Rauschenbach, B.; Breuer, K.; Leonhardt, G.

1990-01-01

Aluminium has been implanted with nitrogen ions at different temperatures. The implanted samples have been characterized by Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS) and electron energy-loss spectroscopy (EELS). Deconvolution procedures are needed to separate the influence of the ion sputter profiling by AES and XPS from the nitrogen-ion-beam-induced effects. The chemical state of Al, N, O and C was identified by deconvolution of the measured spectra. In general, there were double-peak structures observed for N 1s and O 1s, identified as contributions from nitrides and weakly bound nitrogen, and oxides and weakly bound oxygen, respectively. Auger analysis confirms the influence of the nitrogen ion fluence on the shape of the concentration distribution. The influence of temperature on the chemical state of implanted aluminium and on the concentration distribution is discussed. (orig.)

Isotope investigation of nitrogen in the hydrosphere

International Nuclear Information System (INIS)

Heaton, T.H.E.

1985-01-01

Compounds of nitrogen are essential, often limiting nutrients, and the nitrogen cycle is therefore one of the most important of the earth's major elements cycles. Of all the cycles, however, the nitrogen cycle is also probably the one most influenced by human activity. This activity has resulted in the increase in reactive nitrogen compounds to such an extent that they now present major forms of pollution. Any strategies aimed at counteracting these disturbances require a better understanding of the sources and reaction processes for nitrogen compounds, and studies of natural variations in 15 N/ 14 N ratio are now being used for this purpose in all parts of the hydrosphere. This paper reviews the isotopic method for tracing sources of nitrate in ground and surface waters

Cyanobacteria in CELSS: Growth strategies for nutritional variation and nitrogen cycling

Science.gov (United States)

Fry, I. V.; Packer, L.

1990-01-01

Cyanobacteria (blue-green algae) are versatile organisms which are capable of adjusting their cellular levels of carbohydrate, protein, and lipid in response to changes in the environment. Under stress conditions there is an imbalance between nitrogen metabolism and carbohydrate/lipid synthesis. The lesion in nitrogen assimilation is at the level of transport: the stress condition diverts energy from the active accumulation of nitrate to the extrusion of salt, and probably inhibits a cold-labile ATP'ace in the case of cold shock. Both situations affect the bioenergetic status of the cell such that the nitrogenous precursors for protein synthesis are depleted. Dispite the inhibition of protein synthesis and growth, photosynthetic reductant generation is relatively unaffected. The high O2 reductant would normally lead to photo-oxidative damage of cellular components; however, the organism copes by channeling the 'excess' reductant into carbon storage products. The increase in glycogen (28 to 35 percent dry weight increase) and the elongation of lipid fatty acid side chains (2 to 5 percent dry weight increase) at the expense of protein synthesis (25 to 34 percent dry weight decrease) results in carbohydrate, lipid and protein ratios that are closer to those required in the human diet. In addition, the selection of nitrogen fixing mutants which excrete ammonium ions present an opportunity to tailor these micro-organisms to meet the specific need for a sub-system to reverse potential loss of fixed nitrogen material.

The fertilizer nitrogen problem

Energy Technology Data Exchange (ETDEWEB)

Olson, R A; Halstead, E H

1974-07-01

A world-wide fossil fuel crisis has surfaced in the past year by reason of shortage and high cost, which is felt throughout all segments of human society. Nor has the agriculture sector, with its very high demand for energy to supply its power, machinery, fertilizer, processing and transport, escaped the energy crisis. Among the agricultural inputs, fertilizer nitrogen is one of major concern. This commodity is currently in extremely short supply, world prices having more than doubled in the past year alone. Serious as this situation is to agricultural production in the highly developed countries of the world, it is a real disaster to the production potential of the developing countries. The birth of the 'Green Revolution' in those countries in the last ten years came about from an amalgamation of higher yielding varieties, improved pest and disease control, better crop watering practices, and the introduction of fertilizer nitrogen. Shortcomings in any one of these requisites invalidates the entire package. (author)

The fertilizer nitrogen problem

International Nuclear Information System (INIS)

Olson, R.A.; Halstead, E.H.

1974-01-01

A world-wide fossil fuel crisis has surfaced in the past year by reason of shortage and high cost, which is felt throughout all segments of human society. Nor has the agriculture sector, with its very high demand for energy to supply its power, machinery, fertilizer, processing and transport, escaped the energy crisis. Among the agricultural inputs, fertilizer nitrogen is one of major concern. This commodity is currently in extremely short supply, world prices having more than doubled in the past year alone. Serious as this situation is to agricultural production in the highly developed countries of the world, it is a real disaster to the production potential of the developing countries. The birth of the 'Green Revolution' in those countries in the last ten years came about from an amalgamation of higher yielding varieties, improved pest and disease control, better crop watering practices, and the introduction of fertilizer nitrogen. Shortcomings in any one of these requisites invalidates the entire package. (author)

Energy Storage Requirements for Achieving 50% Solar Photovoltaic Energy Penetration in California

Energy Technology Data Exchange (ETDEWEB)

Denholm, Paul; Margolis, Robert

2016-08-01

We estimate the storage required to enable PV penetration up to 50% in California (with renewable penetration over 66%), and we quantify the complex relationships among storage, PV penetration, grid flexibility, and PV costs due to increased curtailment. We find that the storage needed depends strongly on the amount of other flexibility resources deployed. With very low-cost PV (three cents per kilowatt-hour) and a highly flexible electric power system, about 19 gigawatts of energy storage could enable 50% PV penetration with a marginal net PV levelized cost of energy (LCOE) comparable to the variable costs of future combined-cycle gas generators under carbon constraints. This system requires extensive use of flexible generation, transmission, demand response, and electrifying one quarter of the vehicle fleet in California with largely optimized charging. A less flexible system, or more expensive PV would require significantly greater amounts of storage. The amount of storage needed to support very large amounts of PV might fit within a least-cost framework driven by declining storage costs and reduced storage-duration needs due to high PV penetration.

Assessment of free-living nitrogen fixing microorganisms for commercial nitrogen fixation. [economic analysis of ammonia production

Science.gov (United States)

Stokes, B. O.; Wallace, C. J.

1978-01-01

Ammonia production by Klebsiella pneumoniae is not economical with present strains and improving nitrogen fixation to its theoretical limits in this organism is not sufficient to achieve economic viability. Because the value of both the hydrogen produced by this organism and the methane value of the carbon source required greatly exceed the value of the ammonia formed, ammonia (fixed nitrogen) should be considered the by-product. The production of hydrogen by KLEBSIELLA or other anaerobic nitrogen fixers should receive additional study, because the activity of nitrogenase offers a significant improvement in hydrogen production. The production of fixed nitrogen in the form of cell mass by Azotobacter is also uneconomical and the methane value of the carbon substrate exceeds the value of the nitrogen fixed. Parametric studies indicate that as efficiencies approach the theoretical limits the economics may become competitive. The use of nif-derepressed microorganisms, particularly blue-green algae, may have significant potential for in situ fertilization in the environment.

The direct and indirect energy requirement of households in the European Union

NARCIS (Netherlands)

Reinders, Angelina H.M.E.; Vringer, K.; Blok, K.

2003-01-01

In this article we evaluate the average energy requirement of households in 11 EU member states. By investigating both the direct (electricity, natural gas, gasoline, etc.) and the indirect energy requirement, i.e. the energy embodied in consumer goods and services, we add to research done on only

Sputtering of solid nitrogen by keV helium ions

DEFF Research Database (Denmark)

Ellegaard, O.; Schou, Jørgen; Sørensen, H.

1993-01-01

Solid nitrogen has become a standard material among the frozen molecular gases for electronic sputtering. We have combined measurements of sputtering yields and energy spectra from nitrogen bombarded by 4-10 keV helium ions. The data show that the erosion is electronic rather than knockon...

[Influence of an elevation of the temperature of water on the digestibility of dry matter, nitrogen and energy of food distributed to the rainbow trout (Salmo gairdneri Rich)].

Science.gov (United States)

Choubert, G; Fauconneau, B; Luquet, P

1982-01-01

Rainbow trout adapted to a water temperature of 10 degrees C were subjected to an abrupt rise in temperature (from 10 to 18 degrees C) in a 24-h period. Fish maintained in recirculated water were fed to satiation twice a day and their feed intakes were recorded. Changes in dry matter, nitrogen and energy digestibility were measured each day at 10 degrees C and during the course of acclimatation to 18 degrees C. Low water temperature (10 degrees C) was characterized by a feed intake of 1.84 g (DM)/fish/day; digestibility values were as follows: dry matter 62.15 p. 100, nitrogen 86.91 p. 100, energy 70.60 p. 100. High water temperature (18 degrees C) was characterized by a feed intake of 3.75 g (DM)/fish/day; digestibility values were as follows: dry matter 66.08 p. 100, nitrogen 89.57 p. 100, energy 73.52 p. 100. The daily patterns in digestibility were affected by the rise in temperature. The digestibility values were stabilized by day 7 after the positive thermal shock.

Methanization, new opportunities for territories. National technical day - 13 May 2014, Paris. Collection of interventions. The Methanization Autonomy Nitrogen energy plan

International Nuclear Information System (INIS)

Bastide, Guillaume; Guilet, Marie; Banville, Sandrine; Rocher, Franck; Brosset, Denis; Chapelat, Nicolas; Le Roy, Philippe; Leboucher, Anne; Boucher, Sophie; Bolduan, Rainer; Pislor, Emilie; Desbles, Matthieu; Garoche, David; Decoopman, Bertrand; Deshayes, Odile; Mazzenga, Anthony; Quaak, Mauritz; Berthelot, Corinne

2014-05-01

This publication contains proceedings of a conference on methanization projects and techniques, notably in rural areas (there were 140 rural installations in France in 2014 and 20 centralised ones). Contributions thus give an overview of the present development of this sector, and of its perspectives over the medium to long term. A first set of contributions addressed the performance of a panel of farm-based and centralised methanization installations with technical, energy, environmental, agronomic and social assessments for 8 units (lessons learned from installation follow-up, recommendations for operation optimisation of 2 units), and a profitability study performed on 21 installations (lessons learned, profitability evolution for 2 installations). The second set of contributions addressed development perspectives of the methanization sector over the medium to long term. Contributions addressed the following issues: how to mobilise and process bio-wastes from big producers, other possible sources (energetic crops, intermediate crops for energy purposes or CIVE or crop residues), the use of digestate to reduce the use of mineral fertilizers, and emerging energetic valorisations of biogas. A last part presents the Methanization Autonomy Nitrogen Energy Plan (the EMAA plan) which aims at managing and valorising nitrogen (notably from breeding effluents), at developing a French model of agricultural methanization. The stakes of methanization for energy transition are outlined, and the operation of a methanization installation is described

Reaction Mechanism for the Formation of Nitrogen Oxides (NO x ) During Coke Oxidation in Fluidized Catalytic Cracking Units

KAUST Repository

Chaparala, Sree Vidya

2015-06-11

Fluidized catalytic cracking (FCC) units in refineries process heavy feedstock obtained from crude oil distillation. While cracking feed, catalysts get deactivated due to coke deposition. During catalyst regeneration by burning coke in air, nitrogen oxides (NOx) are formed. The increase in nitrogen content in feed over time has resulted in increased NOx emissions. To predict NOx concentration in flue gas, a reliable model for FCC regenerators is needed that requires comprehensive understanding and accurate kinetics for NOx formation. Based on the nitrogen-containing functional groups on coke, model molecules are selected to study reactions between coke-bound nitrogen and O2 to form NO and NO2 using density functional theory. The reaction kinetics for the proposed pathways are evaluated using transition state theory. It is observed that the addition of O2 on coke is favored only when the free radical is present on the carbon atom instead of nitrogen atom. Thus, NOx formation during coke oxidation does not result from the direct attack by O2 on N atoms of coke, but from the transfer of an O atom to N from a neighboring site. The low activation energies required for NO formation indicate that it is more likely to form than NO2 during coke oxidation. The favorable pathways for NOx formation that can be used in FCC models are identified. Copyright © 2015 Taylor & Francis Group, LLC.

Express analysis of nitrogen oxides in combustion products of energy fuels

Energy Technology Data Exchange (ETDEWEB)

Avdeeva, A A; Tishina, T A; Kormilitsyn, V I

1981-07-01

This paper discusses accuracy of 3 gas analyzers used in the USSR for determination of nitrogen oxide content in smoke emitted to the atmosphere by coal-fired fossil-fuel power plants. UG-2 colorimeter measures content of nitric oxide and nitrogen dioxide with accuracy of about 25% (nominal accuracy amounts to 10%). Its range of measurement does not exceed 0.2 g/m/sup 3/. Duration of measurement is from 5 to 7 min. GKh-4 colorimeter with range from 0 to 0.16 g/m/sup 3/ of nitrogen dioxide and nitric oxide is characterized by accuracy of 25%. Presence of sulfur dioxide increases measurement error up to 50%. GKh-4 supplies satisfactory results when nitrogen oxide content ranges from 0.001 to 0.0013%. Design of a new colorimeter, Ehvdiometr-1, developed by EhNIN is evaluated. The maximum error of the instrument does not exceed 5%. It is not influenced by the presence of hydrogen, carbon monoxide or methane when their content is below 10%, or by carbon dioxide when its content is below 20%, or by sulfur dioxide when its content is below 1%. Duration of measurements amounts to about 10 min. Under operational conditions in power plants the accuracy of the Ehvdiometr-1 is 5 times higher than that of the GKh-4 colorimeter. 5 refs.

The value of symbiotic nitrogen fixation by grain legumes in comparison to the cost of nitrogen fertilizer used in developing countries

International Nuclear Information System (INIS)

Hardarson, G.; Bunning, S.; Montanez, A.; Roy, R.; MacMillan, A.

2001-01-01

A great challenge lies in devising more sustainable farming systems without compromising food production levels and food security. Obviously, increasing productivity is necessary to accommodate growth in the global population. World wide, the environmental factors that most severely restrict plant growth are the availability of water and nitrogen. The challenges in developing countries are to find ways of meeting this additional nitrogen demand without concomitant degrading natural productivity. Widespread adoption of biological nitrogen fixation (BNF) would contribute to this goal. BNF, together with adequate N management in the ecosystem, appears to be the most promising alternative to increasing the use of inorganic fertiliser nitrogen. BNF technologies represent economic, sustainable and environmentally friendly means of ensuring the nitrogen requirement of an agro-ecosystem. Here we investigate the value of BNF by grain legumes and compares it to the cost of nitrogen fertilizer used in developing countries. Our data show that major grain legumes fix approximately 11.1 million metric tons of nitrogen per annum in developing countries. If this N was supplied by inorganic fertiliser one would have to apply at least double that amount to achieve the same yields, and this would cost approximately 6.7 billion US dollars. As the eight major grain legumes grown in developing countries contribute 30 - 40% of the annual N requirement the contribution of BNF is of great economic and environmental importance. (author)

Feasibility analysis of gas turbine inlet air cooling by means of liquid nitrogen evaporation for IGCC power augmentation

International Nuclear Information System (INIS)

Morini, Mirko; Pinelli, Michele; Spina, Pier Ruggero; Vaccari, Anna; Venturini, Mauro

2015-01-01

Integrated Gasification Combined Cycles (IGCC) are energy systems mainly composed of a gasifier and a combined cycle power plant. Since the gasification process usually requires oxygen as the oxidant, an Air Separation Unit (ASU) is also part of the plant. In this paper, a system for power augmentation in IGCC is evaluated. The system is based on gas turbine inlet air cooling by means of liquid nitrogen spray. In fact, nitrogen is a product of the ASU, but is not always exploited. In the proposed plant, the nitrogen is first liquefied to be used for inlet air cooling or stored for later use. This system is not characterized by the limits of water evaporative cooling systems (the lower temperature is limited by air saturation) and refrigeration cooling (the effectiveness is limited by the pressure drop in the heat exchanger). A thermodynamic model of the system is built by using a commercial code for energy conversion system simulation. A sensitivity analysis on the main parameters is presented. Finally the model is used to study the capabilities of the system by imposing the real temperature profiles of different sites for a whole year and by comparing to traditional inlet air cooling strategies. - Highlights: • Gas turbine inlet air cooling by means of liquid nitrogen spray. • Humidity condensation may form a fog which provides further power augmentation. • High peak and off peak electric energy price ratios make the system profitable

Maintenance energy requirements in miniature colony dogs.

Science.gov (United States)

Serisier, S; Weber, M; Feugier, A; Fardet, M-O; Garnier, F; Biourge, V; German, A J

2013-05-01

There are numerous reports of maintenance energy requirements (MER) in dogs, but little information is available about energy requirements of miniature dog breeds. In this prospective, observational, cohort study, we aimed to determine MER in dogs from a number of miniature breeds and to determine which factors were associated with it. Forty-two dogs participated in the study. MER was calculated by determining daily energy intake (EI) during a period of 196 days (28-359 days) when body weight did not change significantly (e.g. ±2% in 12 weeks). Estimated median MER was 473 kJ/kg(0.75) /day (285-766 kJ/kg(0.75) /day), that is, median 113 kcal/kg(0.75) /day (68-183 kcal/kg(0.75) /day). In the obese dogs that lost weight, median MER after weight loss was completed was 360 kJ/kg(0.75) /day (285-515 kJ/kg(0.75) /day), that is, 86 kcal/kg(0.75) /day, (68-123 kcal/kg(0.75) /day). Simple linear regression analysis suggested that three breeds (e.g. Chihuahua, p = 0.002; Yorkshire terrier, p = 0.039; dachshund, p = 0.035) had an effect on MER. In addition to breed, simple linear regression revealed that neuter status (p = 0.079) and having previously been overweight (p = 0.002) were also of significance. However, with multiple linear regression analysis, only previous overweight status (MER less in dogs previously overweight p = 0.008) and breed (MER greater in Yorkshire terriers [p = 0.029] and less in Chihuahuas [p = 0.089]) remained in the final model. This study is the first to estimate MER in dogs of miniature breeds. Although further information from pet dogs is now needed, the current work will be useful for setting energy and nutrient requirement in such dogs for the future. Journal of Animal Physiology and Animal Nutrition © 2013 Blackwell Verlag GmbH.

Structure, thermodynamic and electronic properties of carbon-nitrogen cubanes and protonated polynitrogen cations

Science.gov (United States)

Chaban, Vitaly V.; Andreeva, Nadezhda A.

2017-12-01

Energy generation and storage are at the center of modern civilization. Energetic materials constitute quite a large class of compounds with a high amount of stored chemical energy that can be released. We hereby use a combination of quantum chemistry methods to investigate feasibility and properties of carbon-nitrogen cubanes and multi-charged polynitrogen cations in the context of their synthesis and application as unprecedented energetic materials. We show that the stored energy increases gradually with the nitrogen content increase. Nitrogen-poor cubanes retain their stabilities in vacuum, even at elevated temperatures. Such molecules will be probably synthesized at some point. In turn, polynitrogen cations are highly unstable, except N8H+, despite they are isoelectronic to all-carbon cubane. Kinetic stability of the cation decays drastically as its total charge increases. High-level thermodynamic calculations revealed that large amounts of energy are liberated upon decompositions of polynitrogen cations, which produce molecular nitrogen, acetylene, and protons. The present results bring a substantial insights to the design of novel high-energy compounds.

Nitrogen evolution during rapid hydropyrolysis of coal

Energy Technology Data Exchange (ETDEWEB)

Xu, W.-C.; Kumagai, M. [Institute of Research and Innovation, Kashiwa (Japan)

2002-12-01

The behavior of nitrogen evolution during rapid hydropyrolysis of coal has been investigated at temperatures ranging from 923 to 1123 K and hydrogen pressure up to 5 MPa using a continuous free fall pyrolyzer. Three coals have been tested in this study. The dominant nitrogen gaseous species is ammonia, together with a little amount of HCN because most of HCN is converted to NH{sub 3} through secondary reactions. The results show that the evolution of nitrogen in coal is caused mainly by devolatilization at temperatures below 973 K, while the evolution of volatile nitrogen in char is accelerated with increasing temperature and hydrogen pressure. The mineral matter in coal act as catalysts to promote the evolution of volatile nitrogen in char to N{sub 2} apparently at high temperatures of 1123 K, as found during pyrolysis of coal by Ohtsuka et al. A pseudo-first-order kinetic model was applied to the evolution of nitrogen in coal during rapid hydropyrolysis. The model shows the activation energy for the nitrogen evolution from coal is 36.6 58.6 kJ/mol while the rate of the nitrogen evolution depends on hydrogen pressure in the order of 0.16 0.24. 41 refs., 11 figs., 3 tabs.

Modelling the ecosystem effects of nitrogen deposition: Model of Ecosystem Retention and Loss of Inorganic Nitrogen (MERLIN

Directory of Open Access Journals (Sweden)

B. J. Cosby

1997-01-01

Full Text Available A catchment-scale mass-balance model of linked carbon and nitrogen cycling in ecosystems has been developed for simulating leaching losses of inorganic nitrogen. The model (MERLIN considers linked biotic and abiotic processes affecting the cycling and storage of nitrogen. The model is aggregated in space and time and contains compartments intended to be observable and/or interpretable at the plot or catchment scale. The structure of the model includes the inorganic soil, a plant compartment and two soil organic compartments. Fluxes in and out of the ecosystem and between compartments are regulated by atmospheric deposition, hydrological discharge, plant uptake, litter production, wood production, microbial immobilization, mineralization, nitrification, and denitrification. Nitrogen fluxes are controlled by carbon productivity, the C:N ratios of organic compartments and inorganic nitrogen in soil solution. Inputs required are: 1 temporal sequences of carbon fluxes and pools- 2 time series of hydrological discharge through the soils, 3 historical and current external sources of inorganic nitrogen; 4 current amounts of nitrogen in the plant and soil organic compartments; 5 constants specifying the nitrogen uptake and immobilization characteristics of the plant and soil organic compartments; and 6 soil characteristics such as depth, porosity, bulk density, and anion/cation exchange constants. Outputs include: 1 concentrations and fluxes of NO3 and NH4 in soil solution and runoff; 2 total nitrogen contents of the organic and inorganic compartments; 3 C:N ratios of the aggregated plant and soil organic compartments; and 4 rates of nitrogen uptake and immobilization and nitrogen mineralization. The behaviour of the model is assessed for a combination of land-use change and nitrogen deposition scenarios in a series of speculative simulations. The results of the simulations are in broad agreement with observed and hypothesized behaviour of nitrogen

Energy management system for power distribution. Interfaces and data communication requirements

International Nuclear Information System (INIS)

Koponen, P.; Lemstroem, B.; Ikonen, J.

1995-01-01

The opening of the electricity market for competition in Finland creates new requirements for the information systems and data communication in distribution utilities. Energy management systems for distribution utilities are needed with interfaces that make it possible to separate the network business from the energy trade business. However, these interfaces should also support optimization of the whole energy supply system of the country. In this report the interfaces and data communication requirements of the energy management system of the electricity trade business are analyzed. To support this subfunctions of the energy management have been analyzed. It was realized that the amount of necessary data transfer and optimization of the national power system both depend strongly on the general rules of the energy markets. (author)

Impact of bioenergy on regionalized nitrogen balances

Science.gov (United States)

Häußermann, Uwe; Klement, Laura; Bach, Martin

2017-04-01

Results of regionalized and overall net-N-balances are used to fulfil different reporting obligations, as well as input data for nitrate leaching modelling (Bach et al. 2014). For Germany, these regionalized net-N-balances are calculated for 402 administrative units on the NUTS-III-level (Landkreise and kreisfreie Städte in Germany), 16 administrative units on the NUTS-I-level (Bundesländer in Germany) and the whole country for every year from 1995 to 2015. The so far existing net-N-balancing method includes nitrogen inputs and outputs of crop production and animal husbandry, however, not the utilization of crops and farmyard manure for energy production (Bach et al. 2014). Due to the introduction of guaranteed feed in tariffs for electricity production from biomass by the German renewable energy law in 2000 and the introduction of more favourable conditions for electricity production from biogas in 2004 (EEG 2000, EEG 2004) in the frame of the German policy of energy transition towards renewable energies („Energiewende"), the electric capacity of biogas plants had a steep increase in the years afterwards, the installed electric capacity increased from 149 MW in 2004 to 5080 MW in 2015 (BMWi and AGEE Stat 2016). The cropping area for the production of energy cops for biogas production increased as well from 0.4 Mio ha in 2007 to 1.393 Mio ha in 2015 (Statista 2017). We introduced a method to calculate the nitrogen input via energy crops, farmyard manure and organic waste, output via biogas digestates and gaseous nitrogen losses via NH3, N2O, NOx and N2 during the anaerobic digestion, digestate storage and spreading on the field, the emission factors for these nitrogen species are obtained from the report on methods and data for the agricultural part of the German national greenhouse gas inventory and informative inventory report (Haenel et al. 2016). To obtain highly resolved information on the distribution and capacity of biogas plants on NUTS-III-level, we

Coupled effects of light and nitrogen source on the urea cycle and nitrogen metabolism over a diel cycle in the marine diatom Thalassiosira pseudonana.

Science.gov (United States)

Bender, Sara J; Parker, Micaela S; Armbrust, E Virginia

2012-03-01

Diatoms are photoautotrophic organisms capable of growing on a variety of inorganic and organic nitrogen sources. Discovery of a complete urea cycle in diatoms was surprising, as this pathway commonly functions in heterotrophic organisms to rid cells of waste nitrogen. To determine how the urea cycle is integrated into cellular nitrogen metabolism and energy management, the centric diatom Thalassiosira pseudonana was maintained in semi-continuous batch cultures on nitrate, ammonium, or urea as the sole nitrogen source, under a 16: 8 light: dark cycle and at light intensities that were low, saturating, or high for growth. Steady-state transcript levels were determined for genes encoding enzymes linked to the urea cycle, urea hydrolysis, glutamine synthesis, pyrimidine synthesis, photorespiration, and energy storage. Transcript abundances were significantly affected by nitrogen source, light intensity and a diel cycle. The impact of N source on differential transcript accumulation was most apparent under the highest light intensity. Models of cellular metabolism under high light were developed based on changes in transcript abundance and predicted enzyme localizations. We hypothesize that the urea cycle is integrated into nitrogen metabolism through its connection to glutamine and in the eventual production of urea. These findings have important implications for nitrogen flow in the cell over diel cycles at surface ocean irradiances. Copyright © 2011 Elsevier GmbH. All rights reserved.

Antimatter Requirements and Energy Costs for Near-Term Propulsion Applications

Science.gov (United States)

Schmidt, G. R.; Gerrish, H. P.; Martin, J. J.; Smith, G. A.; Meyer, K. J.

1999-01-01

The superior energy density of antimatter annihilation has often been pointed to as the ultimate source of energy for propulsion. However, the limited capacity and very low efficiency of present-day antiproton production methods suggest that antimatter may be too costly to consider for near-term propulsion applications. We address this issue by assessing the antimatter requirements for six different types of propulsion concepts, including two in which antiprotons are used to drive energy release from combined fission/fusion. These requirements are compared against the capacity of both the current antimatter production infrastructure and the improved capabilities that could exist within the early part of next century. Results show that although it may be impractical to consider systems that rely on antimatter as the sole source of propulsive energy, the requirements for propulsion based on antimatter-assisted fission/fusion do fall within projected near-term production capabilities. In fact, a new facility designed solely for antiproton production but based on existing technology could feasibly support interstellar precursor missions and omniplanetary spaceflight with antimatter costs ranging up to $6.4 million per mission.

The millennium development goals and household energy requirements in Nigeria.

Science.gov (United States)

Ibitoye, Francis I

2013-01-01

Access to clean and affordable energy is critical for the realization of the United Nations' Millennium Development Goals, or MDGs. In many developing countries, a large proportion of household energy requirements is met by use of non-commercial fuels such as wood, animal dung, crop residues, etc., and the associated health and environmental hazards of these are well documented. In this work, a scenario analysis of energy requirements in Nigeria's households is carried out to compare estimates between 2005 and 2020 under a reference scenario, with estimates under the assumption that Nigeria will meet the millennium goals. Requirements for energy under the MDG scenario are measured by the impacts on energy use, of a reduction by half, in 2015, (a) the number of household without access to electricity for basic services, (b) the number of households without access to modern energy carriers for cooking, and (c) the number of families living in one-room households in Nigeria's overcrowded urban slums. For these to be achieved, household electricity consumption would increase by about 41% over the study period, while the use of modern fuels would more than double. This migration to the use of modern fuels for cooking results in a reduction in the overall fuelwood consumption, from 5 GJ/capita in 2005, to 2.9 GJ/capita in 2015.

Nitrogen footprints: Regional realities and options to reduce nitrogen loss to the environment Ambio

NARCIS (Netherlands)

Shibata, H.; Galloway, J.N.; Leach, A.M.; Noll, C.; Erisman, J.W.

2016-01-01

Nitrogen (N) management presents a sustainability dilemma: N is strongly linked to energy and food production, but excess reactive N causes environmental pollution. The N footprint is an indicator that quantifies reactive N losses to the environment from consumption and production of food and the

Body composition and net energy requirements of Brazilian Somali lambs

Directory of Open Access Journals (Sweden)

Elzânia S. Pereira

2014-12-01

Full Text Available The aim of this study was to determine the energy requirements for maintenance (NEm and growth of 48 Brazilian Somali ram lambs with an average initial body weight of 13.47±1.76 kg. Eight animals were slaughtered at the trials beginning as a reference group to estimate the initial empty body weight (EBW and body composition. The remaining animals were assigned to a randomised block design with eight replications per block and five diets with increasing metabolisable energy content (4.93, 8.65, 9.41, 10.12 and 11.24 MJ/kg dry matter. The logarithm of heat production was regressed against metabolisable energy intake (MEI, and the NEm (kJ/kg0.75 EBW/day were estimated by extrapolation, when MEI was set at zero. The NEm was 239.77 kJ/kg0.75 EBW/day. The animal’s energy and EBW fat contents increased from 11.20 MJ/kg and 208.54 g/kg to 13.54 MJ/kg and 274.95 g/kg of EBW, respectively, as the BW increased from 13 to 28.70 kg. The net energy requirements for EBW gain increased from 13.79 to 16.72 MJ/kg EBW gain for body weights of 13 and 28.70 kg. Our study indicated the net energy requirements for maintenance in Brazilian Somali lambs were similar to the values commonly recommended by the United States’ nutritional system, but lower than the values recommended by Agricultural Research Council and Commonwealth Scientific and Industrial Research Organization. Net requirements for weight gain were less compared to the values commonly recommended by nutritional system of the United States.

Thermodynamic Modeling and Mechanical Design of a Liquid Nitrogen Vaporization and Pressure Building Device

Science.gov (United States)

Leege, Brian J.

The design of a liquid nitrogen vaporization and pressure building device that has zero product waste while recovering some of its stored energy is of interest for the cost reduction of nitrogen for use in industrial processes. Current devices may waste up to 30% of the gaseous nitrogen product by venting it to atmosphere. Furthermore, no attempt is made to recover the thermal energy available in the coldness of the cryogen. A seven step cycle with changing volumes and ambient heat addition is proposed, eliminating all product waste and providing the means of energy recovery from the nitrogen. This thesis discusses the new thermodynamic cycle and modeling as well as the mechanical design and testing of a prototype device. The prototype was able to achieve liquid nitrogen vaporization and pressurization up to 1000 psi, while full cycle validation is ongoing with promising initial results.

Cytological effect of nitrogen ion implantation into Stevia

International Nuclear Information System (INIS)

Shen Mei; Wang Cailian; Chen Qiufang; Lu Ting; Shu Shizhen

1997-01-01

Dry seeds of Stevia were implanted by 35∼150 keV nitrogen ion with various doses. The cytological effect on M 1 was studied. The results showed that nitrogen ion beam was able to induce variation on chromosome structure in root tip cells. The rate of cells with chromosome aberration was increased with the increased with the increase of ion beam energy and dose. However, there was no significant linear regression relationship between ion dose and aberration rate. The cytological effect of nitrogen ion implantation was lower than that of γ-rays

A Systems Approach to Nitrogen Delivery

Energy Technology Data Exchange (ETDEWEB)

Goins, Bobby [Y-12 National Security Complex, Oak Ridge, TN (United States)

2017-10-23

A systems based approach will be used to evaluate the nitrogen delivery process. This approach involves principles found in Lean, Reliability, Systems Thinking, and Requirements. This unique combination of principles and thought process yields a very in depth look into the system to which it is applied. By applying a systems based approach to the nitrogen delivery process there should be improvements in cycle time, efficiency, and a reduction in the required number of personnel needed to sustain the delivery process. This will in turn reduce the amount of demurrage charges that the site incurs. In addition there should be less frustration associated with the delivery process.

A Systems Approach to Nitrogen Delivery

Energy Technology Data Exchange (ETDEWEB)

Goins, Bobby [Y-12 National Security Complex, Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)

2017-10-17

A systems based approach will be used to evaluate the nitrogen delivery process. This approach involves principles found in Lean, Reliability, Systems Thinking, and Requirements. This unique combination of principles and thought process yields a very in depth look into the system to which it is applied. By applying a systems based approach to the nitrogen delivery process there should be improvements in cycle time, efficiency, and a reduction in the required number of personnel needed to sustain the delivery process. This will in turn reduce the amount of demurrage charges that the site incurs. In addition there should be less frustration associated with the delivery process.

Toward a mechanistic modeling of nitrogen limitation on vegetation dynamics.

Science.gov (United States)

Xu, Chonggang; Fisher, Rosie; Wullschleger, Stan D; Wilson, Cathy J; Cai, Michael; McDowell, Nate G

2012-01-01

Nitrogen is a dominant regulator of vegetation dynamics, net primary production, and terrestrial carbon cycles; however, most ecosystem models use a rather simplistic relationship between leaf nitrogen content and photosynthetic capacity. Such an approach does not consider how patterns of nitrogen allocation may change with differences in light intensity, growing-season temperature and CO(2) concentration. To account for this known variability in nitrogen-photosynthesis relationships, we develop a mechanistic nitrogen allocation model based on a trade-off of nitrogen allocated between growth and storage, and an optimization of nitrogen allocated among light capture, electron transport, carboxylation, and respiration. The developed model is able to predict the acclimation of photosynthetic capacity to changes in CO(2) concentration, temperature, and radiation when evaluated against published data of V(c,max) (maximum carboxylation rate) and J(max) (maximum electron transport rate). A sensitivity analysis of the model for herbaceous plants, deciduous and evergreen trees implies that elevated CO(2) concentrations lead to lower allocation of nitrogen to carboxylation but higher allocation to storage. Higher growing-season temperatures cause lower allocation of nitrogen to carboxylation, due to higher nitrogen requirements for light capture pigments and for storage. Lower levels of radiation have a much stronger effect on allocation of nitrogen to carboxylation for herbaceous plants than for trees, resulting from higher nitrogen requirements for light capture for herbaceous plants. As far as we know, this is the first model of complete nitrogen allocation that simultaneously considers nitrogen allocation to light capture, electron transport, carboxylation, respiration and storage, and the responses of each to altered environmental conditions. We expect this model could potentially improve our confidence in simulations of carbon-nitrogen interactions and the vegetation

Toward a Mechanistic Modeling of Nitrogen Limitation on Vegetation Dynamics

Science.gov (United States)

Xu, Chonggang; Fisher, Rosie; Wullschleger, Stan D.; Wilson, Cathy J.; Cai, Michael; McDowell, Nate G.

2012-01-01

Nitrogen is a dominant regulator of vegetation dynamics, net primary production, and terrestrial carbon cycles; however, most ecosystem models use a rather simplistic relationship between leaf nitrogen content and photosynthetic capacity. Such an approach does not consider how patterns of nitrogen allocation may change with differences in light intensity, growing-season temperature and CO2 concentration. To account for this known variability in nitrogen-photosynthesis relationships, we develop a mechanistic nitrogen allocation model based on a trade-off of nitrogen allocated between growth and storage, and an optimization of nitrogen allocated among light capture, electron transport, carboxylation, and respiration. The developed model is able to predict the acclimation of photosynthetic capacity to changes in CO2 concentration, temperature, and radiation when evaluated against published data of Vc,max (maximum carboxylation rate) and Jmax (maximum electron transport rate). A sensitivity analysis of the model for herbaceous plants, deciduous and evergreen trees implies that elevated CO2 concentrations lead to lower allocation of nitrogen to carboxylation but higher allocation to storage. Higher growing-season temperatures cause lower allocation of nitrogen to carboxylation, due to higher nitrogen requirements for light capture pigments and for storage. Lower levels of radiation have a much stronger effect on allocation of nitrogen to carboxylation for herbaceous plants than for trees, resulting from higher nitrogen requirements for light capture for herbaceous plants. As far as we know, this is the first model of complete nitrogen allocation that simultaneously considers nitrogen allocation to light capture, electron transport, carboxylation, respiration and storage, and the responses of each to altered environmental conditions. We expect this model could potentially improve our confidence in simulations of carbon-nitrogen interactions and the vegetation feedbacks

Toward a mechanistic modeling of nitrogen limitation on vegetation dynamics.

Directory of Open Access Journals (Sweden)

Chonggang Xu

Full Text Available Nitrogen is a dominant regulator of vegetation dynamics, net primary production, and terrestrial carbon cycles; however, most ecosystem models use a rather simplistic relationship between leaf nitrogen content and photosynthetic capacity. Such an approach does not consider how patterns of nitrogen allocation may change with differences in light intensity, growing-season temperature and CO(2 concentration. To account for this known variability in nitrogen-photosynthesis relationships, we develop a mechanistic nitrogen allocation model based on a trade-off of nitrogen allocated between growth and storage, and an optimization of nitrogen allocated among light capture, electron transport, carboxylation, and respiration. The developed model is able to predict the acclimation of photosynthetic capacity to changes in CO(2 concentration, temperature, and radiation when evaluated against published data of V(c,max (maximum carboxylation rate and J(max (maximum electron transport rate. A sensitivity analysis of the model for herbaceous plants, deciduous and evergreen trees implies that elevated CO(2 concentrations lead to lower allocation of nitrogen to carboxylation but higher allocation to storage. Higher growing-season temperatures cause lower allocation of nitrogen to carboxylation, due to higher nitrogen requirements for light capture pigments and for storage. Lower levels of radiation have a much stronger effect on allocation of nitrogen to carboxylation for herbaceous plants than for trees, resulting from higher nitrogen requirements for light capture for herbaceous plants. As far as we know, this is the first model of complete nitrogen allocation that simultaneously considers nitrogen allocation to light capture, electron transport, carboxylation, respiration and storage, and the responses of each to altered environmental conditions. We expect this model could potentially improve our confidence in simulations of carbon-nitrogen interactions and the

Substitutional Nitrogen in Nanodiamond and Bucky-Diamond Particles

Energy Technology Data Exchange (ETDEWEB)

Barnard, Amanda S.; Sternberg, Michael G.

2005-09-15

The inclusion of dopants (such as nitrogen) in diamond nanoparticles is expected to be important for use in future nanodevices, such as qubits for quantum computing. Although most commercial diamond nanoparticles contain a small fraction of nitrogen, it is still unclear whether it is located within the core or at the surface of the nanoparticle. Presented here are density functional tight binding simulations examining the configuration, potential energy surface, and electronic charge of substitutional nitrogen in nanodiamond and bucky-diamond particles. The results predict that nitrogen is likely to be positioned at the surface of both hydrogenated nanodiamond and (dehydrogenated) bucky-diamond, and that the coordination of the dopants within the particles is dependent upon the surface structure.

84 K nitrogen system for the SSC

International Nuclear Information System (INIS)

McAshan, M.; Thirumaleshwar, M.; Abramovich, S.; Ganni, V.; Scheidemantle, A.

1992-01-01

The nitrogen system for the Superconducting Super Collider (SSC) is designed to provide the 84 K (nominal) shield refrigeration for the collider rings. Liquid nitrogen is supplied to the collider tunnel from one, two, or more locations on the surface through the service shafts and is distributed along, the 87 km of both rings by the 84 K shield lines. Additional design requirements for the nitrogen distribution system include precooling, fluid supply to the helium plants, supplying makeup liquid nitrogen to the reservoirs located at the entrance of the main shafts, and providing an efficient cooldown means for the cold mass from 300 K to 90 K. The operational modes and possible emergency and maintenance conditions of the collider are taken into account for the nitrogen system design. The status of our work, including design considerations that address thermal aspects (heat load, recooling scheme, etc.) and hydraulic aspects (pressures, elevations, distances, etc.) of the nitrogen system will be discussed

Heavily nitrogen doped, graphene supercapacitor from silk cocoon

International Nuclear Information System (INIS)

Sahu, Vikrant; Grover, Sonia; Tulachan, Brindan; Sharma, Meenakshi; Srivastava, Gaurav; Roy, Manas; Saxena, Manav; Sethy, Niroj; Bhargava, Kalpana; Philip, Deepu; Kim, Hansung; Singh, Gurmeet; Singh, Sushil Kumar; Das, Mainak; Sharma, Raj Kishore

2015-01-01

Doping of graphene with nitrogen is of much interest, since it improves the overall conductivity and supercapacitive properties. Besides conductivity, nitrogen doping also enhances the pseudo-capacitance due to fast and reversible surface redox processes. In this work, we have developed a cheap and easy process for synthesizing heavily nitrogen doped graphene (15% nitrogen) from non-mulberry silk cocoon membrane (Tassar, Antheraea mylitta) by pyrolyzing the cocoon at 400 °C in argon atmosphere. Further we have investigated the performance of this heavily ‘nitrogen doped graphene’ (NDG) in a supercapacitor device. Our results suggest that NDG obtained from cocoon has improved supercapacitor performance. The improved performance is due to the high electronegativity of nitrogen that forms dipoles on the graphene surface. These dipoles consequently enhance the tendency of graphene to attract charged species to its surface. This is a green and clean synthesis approach for developing electronic materials for energy applications

Nitrogen-Doped Graphene for Photocatalytic Hydrogen Generation.

Science.gov (United States)

Chang, Dong Wook; Baek, Jong-Beom

2016-04-20

Photocatalytic hydrogen (H2 ) generation in a water splitting process has recently attracted tremendous interest because it allows the direct conversion of clean and unlimited solar energy into the ideal energy resource of H2 . For efficient photocatalytic H2 generation, the role of the photocatalyst is critical. With increasing demand for more efficient, sustainable, and cost-effective photocatalysts, various types of semiconductor photocatalysts have been intensively developed. In particular, on the basis of its superior catalytic and tunable electronic properties, nitrogen-doped graphene is a potential candidate for a high-performance photocatalyst. Nitrogen-doped graphene also offers additional advantages originating from its unique two-dimensional sp(2) -hybridized carbon network including a large specific surface area and exceptional charge transport properties. It has been reported that nitrogen-doped graphene can play diverse but positive functions including photo-induced charge acceptor/meditator, light absorber from UV to visible light, n-type semiconductor, and giant molecular photocatalyst. Herein, we summarize the recent progress and general aspects of nitrogen-doped graphene as a photocatalyst for photocatalytic H2 generation. In addition, challenges and future perspectives in this field are also discussed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Electronic structure of graphene nanoribbons doped with nitrogen atoms: a theoretical insight.

Science.gov (United States)

Torres, A E; Fomine, S

2015-04-28

The electronic structure of graphene nanoribbons doped with a graphitic type of nitrogen atoms has been studied using B3LYP, B2PLYP and CAS methods. In all but one case the restricted B3LYP solutions were unstable and the CAS calculations provided evidence for the multiconfigurational nature of the ground state with contributions from two dominant configurations. The relative stability of the doped nanoribbons depends mostly on the mutual position of the dopant atoms and notably less on the position of nitrogen atoms within the nanoribbon. N-graphitic doping affects cationic states much more than anionic ones due the participation of the nitrogen atoms in the stabilization of the positive charge, resulting in a drop in ionization energies (IPs) for N-graphitic doped systems. Nitrogen atoms do not participate in the negative charge stabilization of anionic species and, therefore, the doping does not affect the electron affinities (EAs). The unrestricted B3LYP method is the method of choice for the calculation of IPs and EAs. Restricted B3LYP and B2PLYP produces unreliable results for both IPs and EAs while CAS strongly underestimates the electron affinities. This is also true for the reorganization energies where restricted B3LYP produces qualitatively incorrect results. Doping changes the reorganization energy of the nanoribbons; the hole reorganization energy is generally higher than the corresponding electron reorganization energy due to the participation of nitrogen atoms in the stabilization of the positive charge.

Utilization of the secondary energy of Itaipu, Parana State, Brazil, for electrolytical ammonia production for nitrogenous fertilizers synthesis; Utilizacao da energia secundaria da usina hidreletrica de Itaipu, PR, Brasil para producao de amonia eletrolitica para sintese de fertilizantes nitrogenados

Energy Technology Data Exchange (ETDEWEB)

Souza, S.N.M. de; Siqueira, J.A.C.

2000-07-01

Secondary energy can be described as a surplus of electrical energy in hydraulic power plant due to the lower demand of energy during some periods of time, and the excess of water in the reservoir, during rainy periods. The largest hydroelectric power plant both in Brazil and South America is Itaipu, jointly operated by Brazil and Paraguay. This power plant has a large amount of secondary energy available, and this energy is lost as no turbine spilled water out of the reservoir. This study proposes the using of this energy for electrolytic hydrogen production and ammonia for nitrogenous fertilizers. The hydrogen is produced as a gas by mean of electrolyses and with the atmospheric nitrogen for the electrolytic ammonia synthesis, used as the most important raw material for the nitrogen fertilizers synthesis. This study performs the determination of the minimal cost of hydrogen production and the correspondent hydrogen production capacity in accordance with the ammonia market for nitrogenated fertilizers in the Center/South region, estimating the better production capacity for an ammonia plant to be installed close to Itaipu.

Energy Storage Requirements for PV Power Ramp Rate Control in Northern Europe

Directory of Open Access Journals (Sweden)

Julius Schnabel

2016-01-01

Full Text Available Photovoltaic (PV generators suffer from fluctuating output power due to the highly fluctuating primary energy source. With significant PV penetration, these fluctuations can lead to power system instability and power quality problems. The use of energy storage systems as fluctuation compensators has been proposed as means to mitigate these problems. In this paper, the behavior of PV power fluctuations in Northern European climatic conditions and requirements for sizing the energy storage systems to compensate them have been investigated and compared to similar studies done in Southern European climate. These investigations have been performed through simulations that utilize measurements from the Tampere University of Technology solar PV power station research plant in Finland. An enhanced energy storage charging control strategy has been developed and tested. Energy storage capacity, power, and cycling requirements have been derived for different PV generator sizes and power ramp rate requirements. The developed control strategy leads to lesser performance requirements for the energy storage systems compared to the methods presented earlier. Further, some differences on the operation of PV generators in Northern and Southern European climates have been detected.

The effect of zilpaterol hydrochloride supplementation on energy metabolism and nitrogen and carbon retention of steers fed at maintenance and fasting intake levels

Science.gov (United States)

An indirect calorimetry trial examined energy metabolism, apparent nutrient digestibility (appND), carbon retention (CR) and nitrogen retention (NR) of cattle supplemented with zilpaterol hydrochloride (Z). Beef steers (n=20; 463 ± 14 kg) blocked (n=5) by weight and source were individually fed and ...

Nitrogen-doped graphene by microwave plasma chemical vapor deposition

International Nuclear Information System (INIS)

Kumar, A.; Voevodin, A.A.; Paul, R.; Altfeder, I.; Zemlyanov, D.; Zakharov, D.N.; Fisher, T.S.

2013-01-01

Rapid synthesis of nitrogen-doped, few-layer graphene films on Cu foil is achieved by microwave plasma chemical vapor deposition. The films are doped during synthesis by introduction of nitrogen gas in the reactor. Raman spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy and scanning tunneling microscopy reveal crystal structure and chemical characteristics. Nitrogen concentrations up to 2 at.% are observed, and the limit is linked to the rigidity of graphene films on copper surfaces that impedes further nitrogen substitutions of carbon atoms. The entire growth process requires only a few minutes without supplemental substrate heating and offers a promising path toward large-scale synthesis of nitrogen-doped graphene films. - Highlights: ► Rapid synthesis of nitrogen doped few layer graphene on Cu foil. ► Defect density increment on 2% nitrogen doping. ► Nitrogen doped graphene is a good protection to the copper metallic surface

Nitrogen-doped graphene by microwave plasma chemical vapor deposition

Energy Technology Data Exchange (ETDEWEB)

Kumar, A., E-mail: kumar50@purdue.edu [Birck Nanotechnolgy Center, Purdue University, West Lafayette, IN 47907 (United States); Voevodin, A.A. [Birck Nanotechnolgy Center, Purdue University, West Lafayette, IN 47907 (United States); Materials and Manufacturing Directorate, Air Force Research Laboratory, WPAFB, OH 45433 (United States); Paul, R. [Birck Nanotechnolgy Center, Purdue University, West Lafayette, IN 47907 (United States); Altfeder, I. [Materials and Manufacturing Directorate, Air Force Research Laboratory, WPAFB, OH 45433 (United States); Zemlyanov, D.; Zakharov, D.N. [Birck Nanotechnolgy Center, Purdue University, West Lafayette, IN 47907 (United States); Fisher, T.S., E-mail: tsfisher@purdue.edu [Birck Nanotechnolgy Center, Purdue University, West Lafayette, IN 47907 (United States); Materials and Manufacturing Directorate, Air Force Research Laboratory, WPAFB, OH 45433 (United States)

2013-01-01

Rapid synthesis of nitrogen-doped, few-layer graphene films on Cu foil is achieved by microwave plasma chemical vapor deposition. The films are doped during synthesis by introduction of nitrogen gas in the reactor. Raman spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy and scanning tunneling microscopy reveal crystal structure and chemical characteristics. Nitrogen concentrations up to 2 at.% are observed, and the limit is linked to the rigidity of graphene films on copper surfaces that impedes further nitrogen substitutions of carbon atoms. The entire growth process requires only a few minutes without supplemental substrate heating and offers a promising path toward large-scale synthesis of nitrogen-doped graphene films. - Highlights: ► Rapid synthesis of nitrogen doped few layer graphene on Cu foil. ► Defect density increment on 2% nitrogen doping. ► Nitrogen doped graphene is a good protection to the copper metallic surface.

21 CFR 862.1515 - Nitrogen (amino-nitrogen) test system.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Nitrogen (amino-nitrogen) test system. 862.1515... Systems § 862.1515 Nitrogen (amino-nitrogen) test system. (a) Identification. A nitrogen (amino-nitrogen) test system is a device intended to measure amino acid nitrogen levels in serum, plasma, and urine...

Energy requirement for the production of silicon solar arrays

Science.gov (United States)

Lindmayer, J.; Wihl, M.; Scheinine, A.; Rosenfield, T.; Wrigley, C. Y.; Morrison, A.; Anderson, J.; Clifford, A.; Lafky, W.

1977-01-01

The results of a study to investigate the feasibility of manufacturing photovoltaic solar array modules by the use of energy obtained from similar or identical photovoltaic sources are presented. The primary objective of this investigation was the characterization of the energy requirements of current and developing technologies which comprise the photovoltaic field. For cross-checking the energies of prevailing technologies data were also used and the wide-range assessment of alternative technologies included different refinement methods, various ways of producing light sheets, semicrystalline cells, etc. Energy data are utilized to model the behavior of a future solar breeder plant under various operational conditions.

Improving mine-mill water network design by reducing water and energy requirements

Energy Technology Data Exchange (ETDEWEB)

Gunson, A.J.; Klein, B.; Veiga, M. [British Columbia Univ., Vancouver, BC (Canada). Norman B. Keevil Inst. of Mining Engineering

2010-07-01

Mining is an energy-intensive industry, and most processing mills use wet processes to separate minerals from ore. This paper discussed water reduction, reuse and recycling options for a mining and mill operation network. A mine water network design was then proposed in order to identify and reduce water and system energy requirements. This included (1) a description of site water balance, (2) a description of potential water sources, (3) a description of water consumers, (4) the construction of energy requirement matrices, and (5) the use of linear programming to reduce energy requirements. The design was used to determine a site water balance as well as to specify major water consumers during mining and mill processes. Potential water supply combinations, water metering technologies, and recycling options were evaluated in order to identify the most efficient energy and water use combinations. The method was used to highlight potential energy savings from the integration of heating and cooling systems with plant water systems. 43 refs., 4 tabs., 3 figs.

Uptake of fertilizer nitrogen and soil nitrogen by rice using 15N-labelled nitrogen fertilizer

International Nuclear Information System (INIS)

Reddy, K.R.; Patrick, W.H. Jr.

1980-01-01

Data from five field experiments using labelled nitrogen fertilizer were used to determine the relative effects of soil nitrogen and fertilizer nitrogen on rice yield. Yield of grain was closely correlated with total aboveground nitrogen uptake (soil + fertilizer), less closely correlated with soil nitrogen uptake and not significantly correlated with fertilizer nitrogen uptake. When yield increase rather than yield was correlated with fertilizer nitrogen uptake, the correlation coefficient was statistically significant. (orig.)

Interaction between Solid Nitrogen and 1-3-keV Electrons

DEFF Research Database (Denmark)

Schou, Jørgen; Sørensen, H.

1978-01-01

V. At 3 keV, the SEE coefficient is 12 times that for solid deuterium. This is attributed partly to the larger production rate for low-energy electrons in nitrogen and partly to the larger escape probability for these electrons. Moreover, measurements were made of the electron-reflection coefficient, both......Experimental studies were made of the interaction between solid nitrogen and beams of 1-2-keV electrons. The projected range for the electrons was measured by means of the mirror-substrate method (gold substrate), giving the result 9.02×1016 E1.75 molecules/cm2 with the energy given in ke...... for solid nitrogen and for the carbon substrate. For nitrogen, it varied from 0.17 el/el at 1 keV to 0.13 el/el at 3 keV, and for carbon it varied from 0.13 to 0.12. The observations are discussed and comparisons made with other theoretical and experimental results. The agreement ranges from good to fair...

Excess nitrogen in the U.S. environment: Trends, risks, and solutions

Science.gov (United States)

Davidson, E.A.; David, M.B.; Galloway, J.N.; Goodale, C.L.; Haeuber, R.; Harrison, J.A.; Howarth, R.W.; Jaynes, D.B.; Lowrance, R.R.; Thomas, Nolan B.; Peel, J.L.; Pinder, R.W.; Porter, E.; Snyder, C.S.; Townsend, A.R.; Ward, M.H.

2011-01-01

It is not surprising that humans have profoundly altered the global nitrogen (N) cycle in an effort to feed 7 billion people, because nitrogen is an essential plant and animal nutrient. Food and energy production from agriculture, combined with industrial and energy sources, have more than doubled the amount of reactive nitrogen circulating annually on land. Humanity has disrupted the nitrogen cycle even more than the carbon (C) cycle. We present new research results showing widespread effects on ecosystems, biodiversity, human health, and climate, suggesting that in spite of decades of research quantifying the negative consequences of too much available nitrogen in the biosphere, solutions remain elusive. There have been important successes in reducing nitrogen emissions to the atmosphere and this has improved air quality. Effective solutions for reducing nitrogen losses from agriculture have also been identified, although political and economic impediments to their adoption remain. Here, we focus on the major sources of reactive nitrogen for the United States (U.S.), their impacts, and potential mitigation options. Sources: ??? Intensive development of agriculture, industry, and transportation has profoundly altered the U.S. nitrogen cycle. ??? Nitrogen emissions from the energy and transportation sectors are declining, but agricultural emissions are increasing. ??? Approximately half of all nitrogen applied to boost agricultural production escapes its intended use and is lost to the environment. Impacts: ??? Two-thirds of U.S. coastal systems are moderately to severely impaired due to nutrient loading; there are now approximately 300 hypoxic (low oxygen) zones along the U.S. coastline and the number is growing. One third of U.S. streams and two fifths of U.S. lakes are impaired by high nitrogen concentrations. ??? Air pollution continues to reduce biodiversity. A nation-wide assessment has documented losses of nitrogen-sensitive native species in favor of exotic

Evaluating the impact of plant-wide WWTP control strategies on energy consumption and greenhouse gas emissions

DEFF Research Database (Denmark)

Flores-Alsina, Xavier; Arnell, Magnus; Amerlinck, Youri

) the control of nitrogen rich returns coming from the sludge treatment. Simulation results show the undesirable effects that energy optimization might have on GHG production: Although off-site CO2 emissions may decrease, primarily as a result of: i) reduced aeration energy requirements; and/or ii) increased...

Strengthening Hadfield steel welds by nitrogen alloying

International Nuclear Information System (INIS)

Efstathiou, C.; Sehitoglu, H.

2009-01-01

Strengthening Hadfield steel weld repairs by introducing nitrogen into the weld region was proven to be feasible via two welding techniques. The first technique required a pure Hadfield steel filler material to be diffusion treated in a high pressure nitrogen gas environment, and subsequently used during tungsten inert gas welding with a pure argon shielding gas. The second technique used a Hadfield steel filler material, and a 10% nitrogen containing argon shielding gas during tungsten inert gas welding. Both techniques increased the yield strength, the hardening rate, and the ultimate strength of the weld region. Using optical microscopy, scanning electron microscopy, and Auger spectroscopy, we determined that the increased strength of the weld region resulted from a combination of nitrogen alloying and microstructural refinement

Multi-stage combustion using nitrogen-enriched air

Science.gov (United States)

Fischer, Larry E.; Anderson, Brian L.

2004-09-14

Multi-stage combustion technology combined with nitrogen-enriched air technology for controlling the combustion temperature and products to extend the maintenance and lifetime cycles of materials in contact with combustion products and to reduce pollutants while maintaining relatively high combustion and thermal cycle efficiencies. The first stage of combustion operates fuel rich where most of the heat of combustion is released by burning it with nitrogen-enriched air. Part of the energy in the combustion gases is used to perform work or to provide heat. The cooled combustion gases are reheated by additional stages of combustion until the last stage is at or near stoichiometric conditions. Additional energy is extracted from each stage to result in relatively high thermal cycle efficiency. The air is enriched with nitrogen using air separation technologies such as diffusion, permeable membrane, absorption, and cryogenics. The combustion method is applicable to many types of combustion equipment, including: boilers, burners, turbines, internal combustion engines, and many types of fuel including hydrogen and carbon-based fuels including methane and coal.

40 CFR 52.1676 - Control strategy: Nitrogen dioxide.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Nitrogen dioxide. 52.1676 Section 52.1676 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...: Nitrogen dioxide. (a) The requirements of § 52.14(c)(3) of this chapter as of May 8, 1974 (39 FR 16347...

40 CFR 52.1576 - Control strategy: Nitrogen dioxide.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control strategy: Nitrogen dioxide. 52.1576 Section 52.1576 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... strategy: Nitrogen dioxide. (a) The requirements of § 52.14(c)(3) of this chapter as of May 8, 1974 (39 FR...

Longitudinal change in energy expenditure and effects on energy requirements of the elderly

Science.gov (United States)

2013-01-01

Background Very little is known about the longitudinal changes in energy requirements in late life. The purposes of this study were to: (1) determine the energy requirements in late life and how they changed during a 7 year time-span, (2) determine whether changes in fat free mass (FFM) were related to changes in resting metabolic rate (RMR), and (3) determine the accuracy of predicted total energy expenditure (TEE) to measured TEE. Methods TEE was assessed via doubly labeled water (DLW) technique in older adults in both 1999 (n = 302; age: 74 ± 2.9 yrs) and again in 2006 (n = 87 age: 82 ± 3.1 yrs). RMR was measured with indirect calorimetry, and body composition was assessed with dual-energy x-ray absorptiometry. Results The energy requirements in the 9th decade of life were 2208 ± 376 kcal/d for men and 1814 ± 337 kcal/d for women. This was a significant decrease from the energy requirements in the 8th decade of life in men (2482 ± 476 kcal/d vs. 2208 ± 376 kcal/d) but not in women (1892 ± 271 kcal/d vs. 1814 ± 337 kcal/d). In addition to TEE, RMR, and activity EE (AEE) also decreased in men, but not women, while FFM decreased in both men and women. The changes in FFM were correlated with changes in RMR for men (r = 0.49, p < 0.05) but not for women (r = −0.08, ns). Measured TEE was similar to Dietary Reference Intake (DRI) predicted TEE for men (2208 ± 56 vs. 2305 ± 35 kcal/d) and women (1814 ± 42 vs. 1781 ± 20 kcal/d). However, measured TEE was different than the World Health Organization (WHO) predicted TEE in men (2208 ± 56 vs. 2915 ± 31 kcal/d (p < 0.05)) and women (1814 ± 42 vs. 2315 ± 21 kcal/d (p < 0.05)). Conclusions TEE, RMR and AEE decreased in men, but not women, from the 8th to 9th decade of life. The DRI equation to predict TEE was comparable to measured TEE, while the WHO equation over-predicted TEE in our elderly population

Quantifying the energy required for groundwater pumping across a regional aquifer system

Science.gov (United States)

Ronayne, M. J.; Shugert, D. T.

2017-12-01

Groundwater pumping can be a substantial source of energy expenditure, particularly in semiarid regions with large depths to water. In this study we assessed the energy required for groundwater pumping in the Denver Basin aquifer system, a group of sedimentary rock aquifers used for municipal water supply in Colorado. In recent decades, declining water levels in the Denver Basin aquifers has resulted in increased pumping lifts and higher energy use rates. We quantified the spatially variable energy intensity for groundwater pumping by analyzing spatial variations in the lift requirement. The median energy intensities for two major aquifers were 1.2 and 1.8 kWh m-3. Considering typical municipal well production rates and household water use in the study area, these results indicate that the energy cost associated with groundwater pumping can be a significant fraction (>20%) of the total electricity consumption for all household end uses. Pumping at this scale (hundreds of municipal wells producing from deep aquifers) also generates substantial greenhouse gas emissions. Analytical wellfield modeling conducted as part of this study clearly demonstrates how multiple components of the lift impact the energy requirement. Results provide guidance for water management strategies that reduce energy expenditure.

Nitrogen-Doped Graphene/Platinum Counter Electrodes for Dye-Sensitized Solar Cells

KAUST Repository

Lin, Chinan; Lee, Chuanpei; Ho, Shute; Wei, Tzuchiao; Chi, Yuwen; Huang, Kunping; He, Jr-Hau

2014-01-01

Nitrogen-doped graphene (NGR) was utilized in dye-sensitized solar cells for energy harvesting. NGR on a Pt-sputtered fluorine-doped tin oxide substrate (NGR/Pt/FTO) as counter electrodes (CEs) achieves the high efficiency of 9.38% via the nitrogen

Corn-based ethanol production compromises goal of reducing nitrogen export by the Mississippi River.

Science.gov (United States)

Donner, Simon D; Kucharik, Christopher J

2008-03-18

Corn cultivation in the United States is expected to increase to meet demand for ethanol. Nitrogen leaching from fertilized corn fields to the Mississippi-Atchafalaya River system is a primary cause of the bottom-water hypoxia that develops on the continental shelf of the northern Gulf of Mexico each summer. In this study, we combine agricultural land use scenarios with physically based models of terrestrial and aquatic nitrogen to examine the effect of present and future expansion of corn-based ethanol production on nitrogen export by the Mississippi and Atchafalaya Rivers to the Gulf of Mexico. The results show that the increase in corn cultivation required to meet the goal of 15-36 billion gallons of renewable fuels by the year 2022 suggested by a recent U.S. Senate energy policy would increase the annual average flux of dissolved inorganic nitrogen (DIN) export by the Mississippi and Atchafalaya Rivers by 10-34%. Generating 15 billion gallons of corn-based ethanol by the year 2022 will increase the odds that annual DIN export exceeds the target set for reducing hypoxia in the Gulf of Mexico to >95%. Examination of extreme mitigation options shows that expanding corn-based ethanol production would make the already difficult challenges of reducing nitrogen export to the Gulf of Mexico and the extent of hypoxia practically impossible without large shifts in food production and agricultural management.

Energy requirements of consumption: Urban form, climatic and socio-economic factors, rebounds and their policy implications

International Nuclear Information System (INIS)

Wiedenhofer, Dominik; Lenzen, Manfred; Steinberger, Julia K.

2013-01-01

Household consumption requires energy to be used at all stages of the economic process, thereby directly and indirectly leading to environmental impacts across the entire production chain. The levels, structure and determinants of energy requirements of household consumption therefore constitute an important avenue of research. Incorporating the full upstream requirements into the analysis helps to avoid simplistic conclusions which would actually only imply shifts between consumption categories without taking the economy wide effects into account. This paper presents the investigation of the direct and indirect primary energy requirements of Australian households, contrasting urban, suburban and rural consumption patterns as well as inter- and intra-regional levels of inequality in energy requirements. Furthermore the spatial and socio-economic drivers of energy consumption for different categories of energy requirements are identified and quantified. Conclusions regarding the relationships between energy requirements, household characteristics, urban form and urbanization processes are drawn and the respective policy implications are explored. - Highlights: • We statistically analyze the energy requirements of consumption in Australia. • Contrasting urban/suburban/rural consumption patterns and spatial inequality. • Energy requirements are influenced by urban form, income and demographics. • Urban households require less direct energy, but their total consumption is higher. • Significant rebound effects can be expected when direct energy use is decreased

Thermoluminescent relative efficiencies of TLD-100 for nitrogen ions respect of gamma radiation

International Nuclear Information System (INIS)

Concha S, K.; Avila, O.; Gamboa de Buen, I.; Rodriguez V, M.; Buenfil, A.E.; Ruiz T, C.; Brandan, M.E.

2004-01-01

The purpose of this work is to measure the thermoluminescent relative efficiency of those TLD-100 dosemeters irradiated with nitrogen ions with respect to the gamma radiation of 60 Co, in function of the linear energy transfer (LET). Two energy of such nitrogen ions were selected that has the same value from LET when impacting in the dosemeters but with E 1 energy (4.8 MeV) and E 2 (9.95 MeV) smaller and greater respectively that the energy of the Bragg peak. (Author)

Reduction of nitrogen: Finnish state of the art

International Nuclear Information System (INIS)

Maekelae, Markku

1987-01-01

In Finland nitrogen has been considered of importance as a limiting growth factor in some coastal areas and heavily polluted lakes. For the present, however, the usefulness of nitrogen removal in municipal wastewater treatment has not beep clear enough and requirements concerning removal of total nitrogen have not been set. The need for nitrogen removal depends mainly on the local conditions. On the coastal regions, nitrogen removal should be started first in the biggest of those municipalities which are loading the Gulf of Finland and the Archipelago Sea. The city of Helsinki has to be prepared for nitrogen removal before the end of the next decade. The adverse effects of ammonia are apparent in many inland water courses. In recent years reduction of ammonia nitrogen in wastewater treatment has been required in some cases, mainly in order to prevent oxygen depletion caused by nitrification in receiving waters. Other important reasons for ammonia reduction have been the adverse effects of ammonia in water supply and the toxic effects of molecular ammonia on fish. In practice, ammonia removal has been performed by nitrification in connection with the activated sludge process. The choice of process combinations and design values have always been based on pilot plant or full scale experiments. In order to reach a sludge retention time long enough during the cold season, the design values of sludge load have been 0.06-0.08 kg BOD 7 /kg MLSS·d in combined carbon oxidation and nitrification processes. At new nitrification plants, denitrification has been used for diminishing the operation costs. (author)

Physical-chemical processes of astrophysical interest: nitrogen chemistry

International Nuclear Information System (INIS)

Loison, Jean-Christophe; Hickson, Kevin; Hily-Blant, Pierre; Faure, Alexandre; Vuitton, Veronique; Bacmann, A.; Maret, Sebastien; Legal, Romane; Rist, Claire; Roncero, Octavio; Larregaray, Pascal; Hochlaf, Majdi; Senent, M. L.; Capron, Michael; Biennier, Ludovic; Carles, Sophie; Bourgalais, Jeremy; Le Picard, Sebastien; Cordier, Daniel; Guillemin, Jean-Claude; Trolez, Yann; Bertin, M.; Poderoso, H.A.M.; Michaut, X.; Jeseck, P.; Philippe, L.; Fillion, J.H.; Fayolle, E.C.; Linnartz, H.; Romanzin, C.; Oeberg, K.I.; Roueff, Evelyne; Pagani, Laurent; Padovani, Marco; Wakelam, Veronique; Honvault, Beatrice; Zvereva-Loete, Natalia; Ouk, Chanda-Malis; Scribano, Yohann; Hartmann, J.M.; Pineau des Forets, Guillaume; Hernandez, Mario; Lique, Francois; Kalugina, Yulia N.; Stoecklin, T.; Hochlaf, M.; Crespos, C.; Larregaray, P.; Martin-Gondre, L.; Petuya, R.; Quintas Sanchez, E.L.; Zanchet, Alexandre; Rodriguez-Lazcano, Yamilet; Mate, Belen

2013-06-01

This document contains the programme and abstracts of contributions to a workshop on nitrogen chemistry within an astrophysical perspective. These contributions have been presented in sessions: Introduction (opening lecture, experimental approaches to molecular astrophysics, theoretical approaches to astrophysics, observations in molecular astrophysics), Physical-chemical theory of the gas phase (time-dependent approach in elementary activity, statistic approach in elementary activity in the case of the N+H_2 reaction, potential energy surfaces for inelastic and reactive collisions, collision rate for N_2H"+, ortho/para selection rules in the chemistry of nitrogen hydrides, cyanides/iso-cyanides excitation in the ISM, CN excitation, radiative association with N_2H as new interstellar anion, ro-vibratory excitation of HCN) Laboratory astrophysics (measurement of reaction products in the CRESUSOL project, reactivity of the CN- anion, N_2 photo-desorption in ices, CRESU study of nitrogen chemistry, chemistry of nitrogen complex molecules), Observations and chemistry of astrophysical media (the problem of interstellar nitrogen fractioning, abundance of N_2 in proto-stellar cores, HNC in Titan atmosphere and nitrogen-related mechanisms in hot Jupiters, HCN and HNC in dark clouds or how theoretical modelling helps in interpreting observations, nitrogen chemistry in cold clouds, deuteration of nitrogen hydrides, nitrogen in interstellar ices, biochemical molecules on Titan, coupling between excitation and chemistry, radiative transfer of nitrogen hydrides, ortho/para chemistry of nitrogen hydrides), Physical-chemical theory of gas-grain interactions (nitrogen reactivity on surfaces, IR spectra of ices of NH_3 and NH_3/N_2 mixtures)

Platforms for energy and nutrient recovery from domestic wastewater: A review.

Science.gov (United States)

Batstone, D J; Hülsen, T; Mehta, C M; Keller, J

2015-12-01

Alternative domestic wastewater treatment processes that recover energy and nutrients while achieving acceptable nutrient limits (650mgCODL(-1). PRR offers the possibility for recovery of nitrogen and other nutrients (including potassium) through assimilative recovery. However, the energetic overhead of this is substantial, requiring 5kWhkgN(-1) as electricity, which compares to ammonia fixation costs. The lower energy costs, and near to market status of LEM treatment make it likely as a recovery platform in the shorter term, while ability to recover other elements such as nitrogen and potassium, as well as enhance favourability on concentrated wastewaters may enhance the desirability of partitioning in the longer term. Copyright © 2014 Elsevier Ltd. All rights reserved.

Forecast of wind energy production and ensuring required balancing power

International Nuclear Information System (INIS)

Merkulov, M.

2010-01-01

The wind energy is gaining larger part of the energy mix around the world as well as in Bulgaria. Having in mind the irregularity of the wind, we are in front of a challenge for management of the power grid in new unknown conditions. The world's experience has proven that there could be no effective management of the grid without forecasting tools, even with small scale of wind power penetration. Application of such tools promotes simple management of large wind energy production and reduction of the quantities of required balancing powers. The share of the expenses and efforts for forecasting of the wind energy is incomparably small in comparison with expenses for keeping additional powers in readiness. The recent computers potential allow simple and rapid processing of large quantities of data from different sources, which provides required conditions for modeling the world's climate and producing sophisticated forecast. (author)

Nitrogen solubility in nickel base multicomponent melts

International Nuclear Information System (INIS)

Bol'shov, L.A.; Stomakhin, A.Ya.; Sokolov, V.M.; Teterin, V.G.

1984-01-01

Applicability of various methods for calculation of nitrogen solubility in high-alloyed nickel base alloys, containing Cr, Fe, W, Mo, Ti, Nb, has been estimated. A possibility is shown to use the formUla, derived for the calculation of nitrogen solubility in iron on the basis of statistical theory for a grid model of solution which does not require limitations for the content of a solvent component. The calculation method has been used for nickel alloys, with the concentration of solvent, iron, being accepted equal to zero, and employing parameters of nitrogen interaction as determined for iron-base alloys

Gene Deletions Resulting in Increased Nitrogen Release by Azotobacter vinelandii: Application of a Novel Nitrogen Biosensor

Science.gov (United States)

Eberhart, Lauren J.; Ohlert, Janet M.; Knutson, Carolann M.; Plunkett, Mary H.

2015-01-01

Azotobacter vinelandii is a widely studied model diazotrophic (nitrogen-fixing) bacterium and also an obligate aerobe, differentiating it from many other diazotrophs that require environments low in oxygen for the function of the nitrogenase. As a free-living bacterium, A. vinelandii has evolved enzymes and transporters to minimize the loss of fixed nitrogen to the surrounding environment. In this study, we pursued efforts to target specific enzymes and further developed screens to identify individual colonies of A. vinelandii producing elevated levels of extracellular nitrogen. Targeted deletions were done to convert urea into a terminal product by disrupting the urease genes that influence the ability of A. vinelandii to recycle the urea nitrogen within the cell. Construction of a nitrogen biosensor strain was done to rapidly screen several thousand colonies disrupted by transposon insertional mutagenesis to identify strains with increased extracellular nitrogen production. Several disruptions were identified in the ammonium transporter gene amtB that resulted in the production of sufficient levels of extracellular nitrogen to support the growth of the biosensor strain. Further studies substituting the biosensor strain with the green alga Chlorella sorokiniana confirmed that levels of nitrogen produced were sufficient to support the growth of this organism when the medium was supplemented with sufficient sucrose to support the growth of the A. vinelandii in coculture. The nature and quantities of nitrogen released by urease and amtB disruptions were further compared to strains reported in previous efforts that altered the nifLA regulatory system to produce elevated levels of ammonium. These results reveal alternative approaches that can be used in various combinations to yield new strains that might have further application in biofertilizer schemes. PMID:25888177

Energetic Nitrogen Ions within the Inner Magnetosphere of Saturn

Science.gov (United States)

Sittler, E. C.; Johnson, R. E.; Richardson, J. D.; Jurac, S.; Moore, M.; Cooper, J. F.; Mauk, B. H.; Smith, H. T.; Michael, M.; Paranicus, C.; Armstrong, T. P.; Tsurutani, B.; Connerney, J. E. P.

2003-05-01

Titan's interaction with Saturn's magnetosphere will result in the energetic ejection of atomic nitrogen atoms into Saturn's magnetosphere due to dissociation of N2 by electrons, ions, and UV photons. The ejection of N atoms into Saturn's magnetosphere will form a nitrogen torus around Saturn with mean density of about 4 atoms/cm3 with source strength of 4.5x1025 atoms/sec. These nitrogen atoms are ionized by photoionization, electron impact ionization and charge exchange reactions producing an N+ torus of 1-4 keV suprathermal ions centered on Titan's orbital position. We will show Voyager plasma observations that demonstrate presence of a suprathermal ion component within Saturn's outer magnetosphere. The Voyager LECP data also reported the presence of inward diffusing energetic ions from the outer magnetosphere of Saturn, which could have an N+ contribution. If so, when one conserves the first and second adiabatic invariant the N+ ions will have energies in excess of 100 keV at Dione's L shell and greater than 400 keV at Enceladus' L shell. Energetic charged particle radial diffusion coefficients are also used to constrain the model results. But, one must also consider the solar wind as another important source of keV ions, in the form of protons and alpha particles, for Saturn's outer magnetosphere. Initial estimates indicate that a solar wind source could dominate in the outer magnetosphere, but various required parameters for this estimate are highly uncertain and will have to await Cassini results for confirmation. We show that satellite sweeping and charged particle precipitation within the middle and outer magnetosphere will tend to enrich N+ ions relative to protons within Saturn's inner magnetosphere as they diffuse radially inward for radial diffusion coefficients that do not violate observations. Charge exchange reactions within the inner magnetosphere can be an important loss mechanism for O+ ions, but to a lesser degree for N+ ions. Initial LECP

Next Generation Carbon-Nitrogen Dynamics Model

Science.gov (United States)

Xu, C.; Fisher, R. A.; Vrugt, J. A.; Wullschleger, S. D.; McDowell, N. G.

2012-12-01

Nitrogen is a key regulator of vegetation dynamics, soil carbon release, and terrestrial carbon cycles. Thus, to assess energy impacts on the global carbon cycle and future climates, it is critical that we have a mechanism-based and data-calibrated nitrogen model that simulates nitrogen limitation upon both above and belowground carbon dynamics. In this study, we developed a next generation nitrogen-carbon dynamic model within the NCAR Community Earth System Model (CESM). This next generation nitrogen-carbon dynamic model utilized 1) a mechanistic model of nitrogen limitation on photosynthesis with nitrogen trade-offs among light absorption, electron transport, carboxylation, respiration and storage; 2) an optimal leaf nitrogen model that links soil nitrogen availability and leaf nitrogen content; and 3) an ecosystem demography (ED) model that simulates the growth and light competition of tree cohorts and is currently coupled to CLM. Our three test cases with changes in CO2 concentration, growing temperature and radiation demonstrate the model's ability to predict the impact of altered environmental conditions on nitrogen allocations. Currently, we are testing the model against different datasets including soil fertilization and Free Air CO2 enrichment (FACE) experiments across different forest types. We expect that our calibrated model will considerably improve our understanding and predictability of vegetation-climate interactions.itrogen allocation model evaluations. The figure shows the scatter plots of predicted and measured Vc,max and Jmax scaled to 25 oC (i.e.,Vc,max25 and Jmax25) at elevated CO2 (570 ppm, test case one), reduced radiation in canopy (0.1-0.9 of the radiation at the top of canopy, test case two) and reduced growing temperature (15oC, test case three). The model is first calibrated using control data under ambient CO2 (370 ppm), radiation at the top of the canopy (621 μmol photon/m2/s), the normal growing temperature (30oC). The fitted model

Molecular nitrogen fixation and nitrogen cycle in nature

Energy Technology Data Exchange (ETDEWEB)

Virtanen, A I

1952-01-01

The origin of nitrogen oxides in the atmosphere is discussed. Evidently only a small proportion of the nitrate-and nitrite-nitrogen found in the precipitation is formed through electric discharges from molecular nitrogen, photochemical nitrogen fixation being probably of greater importance. Formation of nitrate nitrogen through atmospheric oxidation of nitrous oxide (N/sub 2/O) evaporating from the soil is also considered likely. Determination of nitrogen compounds at different altitudes is indispensable for gaining information of the N/sub 2/-fixation in the atmosphere and, in general, of the origin of nitrogen oxides and their decomposition. International cooperation is needed for this as well as for the quantitative determination of the nitrogen compounds removed from the soil by leaching and brought by waters into the seas.

Cost-optimal levels of minimum energy performance requirements in the Danish Building Regulations

Energy Technology Data Exchange (ETDEWEB)

Aggerholm, S.

2013-09-15

The purpose of the report is to analyse the cost optimality of the energy requirements in the Danish Building Regulations 2010, BR10 to new building and to existing buildings undergoing major renovation. The energy requirements in the Danish Building Regulations have by tradition always been based on the cost and benefits related to the private economical or financial perspective. Macro economical calculations have in the past only been made in addition. The cost optimum used in this report is thus based on the financial perspective. Due to the high energy taxes in Denmark there is a significant difference between the consumer price and the macro economical for energy. Energy taxes are also paid by commercial consumers when the energy is used for building operation e.g. heating, lighting, ventilation etc. In relation to the new housing examples the present minimum energy requirements in BR 10 all shows gaps that are negative with a deviation of up till 16 % from the point of cost optimality. With the planned tightening of the requirements to new houses in 2015 and in 2020, the energy requirements can be expected to be tighter than the cost optimal point, if the costs for the needed improvements don't decrease correspondingly. In relation to the new office building there is a gap of 31 % to the point of cost optimality in relation to the 2010 requirement. In relation to the 2015 and 2020 requirements there are negative gaps to the point of cost optimality based on today's prices. If the gaps for all the new buildings are weighted to an average based on mix of building types and heat supply for new buildings in Denmark there is a gap of 3 % in average for the new building. The excessive tightness with today's prices is 34 % in relation to the 2015 requirement and 49 % in relation to the 2020 requirement. The component requirement to elements in the building envelope and to installations in existing buildings adds up to significant energy efficiency

The phycobilisomes of Synechococcus sp are constructed to minimize nitrogen use in nitrogen-limited cells and to maximize energy capture in energy-limited cells

Czech Academy of Sciences Publication Activity Database

Ruan, Z.; Prášil, Ondřej; Giordano, Mario

2018-01-01

Roč. 150, JUN (2018), s. 152-160 ISSN 0098-8472 R&D Projects: GA MŠk(CZ) LO1416 Institutional support: RVO:61388971 Keywords : Nitrogen * Nitrate * Ammonium Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 4.369, year: 2016

Properties of high pressure nitrogen-argon and nitrogen-xenon gas scintillators

International Nuclear Information System (INIS)

Tornow, W.; Huck, H.; Koeber, H.J.; Mertens, G.

1976-01-01

Investigations of scintillation light output and energy resolution have been made at pressures up to 90 atm in gaseous mixtures of nitrogen with both argon and xenon by stopping of 210 Po-alpha particles. In the absence of a wavelength shifter, the N 2 -Ar mixtures gave a maximum pulse height at a ratio of nitrogen to argon partial pressures rsub(N 2 /Ar) approximately =0.2. However, when using the wavelength shifter diphenyl stilbene (DPS), the measured light output was much larger at lower values of rsub(N 2 /Ar), whereas for rsub(N 2 /Ar)>0.2 pulse height and energy resolution of the studied N 2 -Ar mixtures were roughly indentical with and without DPS. The N 2 -Xe gas mixtures exhibited a similar dependence of pulse height and energy resolution to that of the N 2 -Ar mixtures employing DPS, but the pulse height was larger by a factor of about 7. A 40 atm 50% N 2 -50% Xe gas scintillator showed an energy resolution ΔE/E=0.25, while an 80 atm 75% N 2 -25% Xe scintillator gave ΔE/E=0.6. The pulse height from the 80 atm N 2 -Xe scintillator was smaller by a factor of about 240 than the pulse height from a 20 atm pure Xe gas scintillator, but larger by a factor of about 20 than the pulse height from a 75 atm pure N 2 gas scintillator. The N 2 -Xe mixtures showed a remarkable increase of light output as the temperature of the gas was descreased. (Auth.)

Nitrogen Requirements and Balance of Protected Cucumber in Coastal Lebanon

International Nuclear Information System (INIS)

Atallah, T.

2003-01-01

Protected cultures are widespread along the Lebanese narrow coastline, encouraged by mild winter conditions. Although one of the most intensive production systems, water and nutrients managements are mostly empirical, based on the experience of the grower himself or of his workers. So far, water has been available in Lebanon, but it will become scarce within ten years. The conservation of water quality by a rational addition of nutrients is particularly relevant to protected cultures. This is important as greenhouses are developed on imported shallow soils that could be fragile and highly vulnerable to pollution. Sound management includes the amount and the forms of fertilizers as well as the modality of fertigation. An experiment was conducted during two spring seasons in a location along the northern coast in a typical unheated greenhouse. The cucumber response to two frequencies and modalities of fertigation was followed: continuous T2C and T3C and discontinuous T2D and T3D every two and three days respectively. Nitrogen recovery by the crop was possible through the use of 15 N-labeled fertilizers. An evaluation of the nitrogen fertilizer fate in the plant-soil system was undertaken in 1999, despite large proportions of Ndff(%) plant N fertilizer recovery was smaller than in the previous season and did not exceed 55% of N inputs

Plasma catalysis for nitrogen fixation reactions

NARCIS (Netherlands)

Patil, B.S.; Wang, Q.; Hessel, V.; Lang, J.; Stankiewicz, A.; Stefanidis, G.

2016-01-01

The preferences for localized chemicals production and changing scenarios of renewable electricity cost gives a renewed boost to plasma-assisted valuable chemicals production. Especially, plasma-assisted nitrogen fixation for fertilizer production has the potential to largely change the energy

Impact of energy efficiency and replacement of diesel fuel with natural gas in public transport on reducing emissions of nitrogen oxides

Energy Technology Data Exchange (ETDEWEB)

Dimitrovski, Dame; Jovanovski, Antonio [Faculty of Mechanical Engineering, ' Ss. Cyril and Methodius' University, Skopje (Macedonia, The Former Yugoslav Republic of)

2014-07-01

This paper analyzes the direct emissions of nitrogen oxides from the public transport (bus) in urban areas in the Republic of Macedonia. As influential factors on which to compare the quantity of these emissions are taken: Penetration of new (energy efficient) technologies in bus transport, the intensity of the bus fleet renewal for public transport and replacement of diesel with natural gas. (Author)

New, national bottom-up estimate for tree-based biological nitrogen fixation in the US

Science.gov (United States)

Nitrogen is a limiting nutrient in many ecosystems, but is also a chief pollutant from human activity. Quantifying human impacts on the nitrogen cycle and investigating natural ecosystem nitrogen cycling both require an understanding of the magnitude of nitrogen inputs from biolo...

Effect of nitrogen and potassium fertilization on radiocesium absorption in soybean

International Nuclear Information System (INIS)

Nihei, Naoto; Hirose, Atsushi; Tanoi, Keitaro; Nakanishi, Tomoko M.

2015-01-01

Radioactive materials that were released during the nuclear accident contaminated the soil and agricultural products. It has become clear that potassium fertilization is effective for the reduction of radiocesium concentrations in agricultural crops. However, apart from reports about potassium, few reports have examined how nitrogen, which has a large effect on crop growth, contributes to the radiocesium absorption. Focusing on this point, we studied the effect of nitrogen and potassium fertilizer on the radiocesium absorption in soybean seedlings. The concentration of radiocesium in the seed of soybean was higher in nitrogen-fertilized plants than in plants grown without fertilizer. The radiocesium concentration in the aboveground biomass increased as the amount of nitrogen fertilization increased. But the concentrations of radiocesium were higher in potassium-fertilized plants at high-N than in plants without added nitrogen and potassium. Further study is required to clarify the factors that incur an increase in radiocesium concentration in response to nitrogen fertilization. Special care is required to start farming soybean on fallow fields evacuated after the accident or on fields where rice has been grown before, which tend to have higher available nitrogen than the regularly cultivated fields. (author)

Prediction equation for estimating total daily energy requirements of special operations personnel.

Science.gov (United States)

Barringer, N D; Pasiakos, S M; McClung, H L; Crombie, A P; Margolis, L M

2018-01-01

Special Operations Forces (SOF) engage in a variety of military tasks with many producing high energy expenditures, leading to undesired energy deficits and loss of body mass. Therefore, the ability to accurately estimate daily energy requirements would be useful for accurate logistical planning. Generate a predictive equation estimating energy requirements of SOF. Retrospective analysis of data collected from SOF personnel engaged in 12 different SOF training scenarios. Energy expenditure and total body water were determined using the doubly-labeled water technique. Physical activity level was determined as daily energy expenditure divided by resting metabolic rate. Physical activity level was broken into quartiles (0 = mission prep, 1 = common warrior tasks, 2 = battle drills, 3 = specialized intense activity) to generate a physical activity factor (PAF). Regression analysis was used to construct two predictive equations (Model A; body mass and PAF, Model B; fat-free mass and PAF) estimating daily energy expenditures. Average measured energy expenditure during SOF training was 4468 (range: 3700 to 6300) Kcal·d- 1 . Regression analysis revealed that physical activity level ( r  = 0.91; P  plan appropriate feeding regimens to meet SOF nutritional requirements across their mission profile.

Reactive nitrogen in the environment and its effect on climate change

International Nuclear Information System (INIS)

Erisman, J.W.; Bleeker, A.; Galloway, J.; Seitzinger, S.; Butterbach-Bahl, K.

2011-01-01

Humans have doubled levels of reactive nitrogen in circulation, largely as a result of fertilizer application and fossil fuel burning. This massive alteration of the nitrogen cycle affects climate, food security, energy security, human health and ecosystem services. Our estimates show that nitrogen currently leads to a net-cooling effect on climate with very high uncertainty. The many complex warming and cooling interactions between nitrogen and climate need to be better assessed, taking also into account the other effects of nitrogen on human health, environment and ecosystem services. Through improved nitrogen management substantial reductions in atmospheric greenhouse gas concentrations could be generated, also allowing for other co-benefits, including improving human health and improved provision of ecosystem services, for example clean air and water, and biodiversity.

Energy Conversion and Storage Requirements for Hybrid Electric Aircraft

Science.gov (United States)

Misra, Ajay

2016-01-01

Among various options for reducing greenhouse gases in future large commercial aircraft, hybrid electric option holds significant promise. In the hybrid electric aircraft concept, gas turbine engine is used in combination with an energy storage system to drive the fan that propels the aircraft, with gas turbine engine being used for certain segments of the flight cycle and energy storage system being used for other segments. The paper will provide an overview of various energy conversion and storage options for hybrid electric aircraft. Such options may include fuel cells, batteries, super capacitors, multifunctional structures with energy storage capability, thermoelectric, thermionic or a combination of any of these options. The energy conversion and storage requirements for hybrid electric aircraft will be presented. The role of materials in energy conversion and storage systems for hybrid electric aircraft will be discussed.

Nitrogen

Science.gov (United States)

Apodaca, Lori E.

2013-01-01

The article presents an overview of the nitrogen chemical market as of July 2013, including the production of ammonia compounds. Industrial uses for ammonia include fertilizers, explosives, and plastics. Other topics include industrial capacity of U.S. ammonia producers CF Industries Holdings Inc., Koch Nitrogen Co., PCS Nitrogen, Inc., and Agrium Inc., the impact of natural gas prices on the nitrogen industry, and demand for corn crops for ethanol production.

Estimating energy requirement in cashew (Anacardium occidentale L.) nut processing operations

Energy Technology Data Exchange (ETDEWEB)

Jekayinfa, S.O. [Department of Agricultural Engineering, Ladoke Akintola University of Technology, P.M.B. 4000, Ogbomoso, Oyo State (Nigeria); Bamgboye, A.I. [Department of Agricultural Engineering, University of Ibadan, Ibadan (Nigeria)

2006-07-15

This work deals with a study on estimation of energy consumption in eight readily defined unit operations of cashew nut processing. Data for analysis were collected from nine cashew nut mills stratified into small, medium and large categories to represent different mechanization levels. Series of equations were developed to easily compute requirements of electricity, fuel and labour for each of the unit operations. The computation of energy use was done using spreadsheet program on Microsoft Excel. The results of application test of the equations show that the total energy intensity in the cashew nut mills varied between 0.21 and 1.161MJ/kg. Electrical energy intensity varied between 0.0052 and 0.029MJ/kg, while thermal energy intensity varied from 0.085 to 1.064MJ/kg. The two identified energy intensive operations in cashew nut processing are cashew nut drying and cashew nut roasting, altogether accounting for over 85% of the total energy consumption in all the three mill categories. Thermal energy, obtained from diesel fuel, represented about 90% of the unit energy cost for cashew nut processing. The developed equations have therefore proven to be a useful tool for carrying out budgeting, forecasting energy requirements and planning plant expansion. (author)

Numerical Research of Nitrogen Oxides Formation for Justification of Modernization of P-49 Nazarovsky State District Power Plant Boiler on the Low-temperature Swirl Technology of Burning

Science.gov (United States)

Trinchenko, A. A.; Paramonov, A. P.; Skouditskiy, V. E.; Anoshin, R. G.

2017-11-01

Compliance with increasingly stringent normative requirements to the level of pollutants emissions when using organic fuel in the energy sector as a main source of heat, demands constant improvement of the boiler and furnace equipment and the power equipment in general. The requirements of the current legislation in the field of environmental protection prescribe compliance with established emission standards for both new construction and the improvement of energy equipment. The paper presents the results of numerical research of low-temperature swirl burning in P-49 Nazarovsky state district power plant boiler. On the basis of modern approaches of the diffusion and kinetic theory of burning and the analysis physical and chemical processes of a fuel chemically connected energy transition in thermal, generation and transformation of gas pollutants, the technological method of nitrogen oxides decomposition on the surface of carbon particles with the formation of environmentally friendly carbonic acid and molecular nitrogen is considered during the work of low-temperature swirl furnace. With the use of the developed model, methodology and computer program, variant calculations of the combustion process were carried out and a quantitative estimate of the emission level of the nitrogen oxides of the boiler being modernized. The simulation results the and the experimental data obtained during the commissioning and balance tests of the P-49 boiler with a new furnace are confirmed that the organization of swirl combustion has allowed to increase the efficiency of work, to reduce slagging, to significantly reduce nitrogen oxide emissions, to improve ignition and burnout of fuel.

The German energy policy: between national requirements and community exigencies

International Nuclear Information System (INIS)

Notz, K.

2007-01-01

Taking into account the strategic and economic stakes that are associated with the security of energy supplies, the German federal government has made of this question one of the priorities of its european presidency. In this note, the author observes a radical change in the German energy policy with the future phaseout of nuclear energy and the perspectives of Russian gas supply. The author also reviews the challenges of the elaboration of a European energy policy, with certain member States refusing to transfer their sovereignty in the energy domain, and the large split between national requirements and community exigencies in this field

Protein leverage effects of beef protein on energy intake in humans.

Science.gov (United States)

Martens, Eveline A; Tan, Sze-Yen; Dunlop, Mandy V; Mattes, Richard D; Westerterp-Plantenga, Margriet S

2014-06-01

The protein leverage hypothesis requires specific evidence that protein intake is regulated more strongly than energy intake. The objective was to determine ad libitum energy intake, body weight changes, appetite profile, and nitrogen balance in response to 3 diets with different protein-to-carbohydrate + fat ratios over 12 consecutive days, with beef as a source of protein. A 3-arm, 12-d randomized crossover study was performed in 30 men and 28 women [mean ± SD age: 33 ± 16 y; body mass index (in kg/m²): 24.4 ± 4.0] with the use of diets containing 5%, 15%, and 30% of energy (En%) from protein, predominantly from beef. Energy intake was significantly lower in the 30En%-protein condition (8.73 ± 1.93 MJ/d) than in the 5En%-protein (9.48 ± 1.67 MJ/d) and 15En%-protein (9.30 ± 1.62 MJ/d) conditions (P = 0.001), stemming largely from lower energy intake during meals (P = 0.001). Hunger (P = 0.001) and desire to eat (P = 0.001) ratings were higher and fullness ratings were lower (P = 0.001) in the 5En%-protein condition than in the 15En%-protein and 30En%-protein conditions. Nitrogen excretion was lower in the 5En%-protein condition (4.7 ± 1.5 g/24 h; P = 0.001) and was higher in the 30En%-protein condition (15.3 ± 8.7 g/24 h; P = 0.001) compared with the 15En%-protein condition (10.0 ± 5.2 g/24 h). Nitrogen balance was maintained in the 5En%-protein condition and was positive in the 15En%- and 30En%-protein conditions (P = 0.001). Complete protein leverage did not occur because subjects did not consume to a common protein amount at the expense of energy balance. Individuals did underconsume relative to energy requirements from high-protein diets. The lack of support for protein leverage effects on a low-protein diet may stem from the fact that protein intake was sufficient to maintain nitrogen balance over the 12-d trial. © 2014 American Society for Nutrition.

Maintenance requirement and deposition efficiency of lysine in pigs

Directory of Open Access Journals (Sweden)

Marcos Speroni Ceron

2013-09-01

Full Text Available The objective of this work was to determine the maintenance requirement and the deposition efficiency of lysine in growing pigs. It was used the incomplete changeover experimental design, with replicates over time. Twelve castrated pigs with average body weight (BW of 52±2 kg were kept in metabolism crates with a controlled temperature of 22ºC. The diets were formulated to supply 30, 50, 60, and 70% of the expected requirements of standardized lysine, and provided at 2.6 times the energy requirements for maintenance. The trial lasted 24 days and was divided into two periods of 12 days: seven days for animal adaptation to the diet and five days for sample collection. The increasing content of lysine in the diet did not affect dry matter intake of the pigs. The amount of nitrogen excreted was 47% of the nitrogen intake, of which 35% was excreted through feces and 65% through urine. The estimated endogenous losses of lysine were 36.4 mg kg-1 BW0.75. The maintenance requirement of lysine for pigs weighing around 50 kg is 40.4 mg kg-1 BW0.75, and the deposition efficiency of lysine is 90%.

Nitrogen concentration estimation with hyperspectral LiDAR

Directory of Open Access Journals (Sweden)

O. Nevalainen

2013-10-01

Full Text Available Agricultural lands have strong impact on global carbon dynamics and nitrogen availability. Monitoring changes in agricultural lands require more efficient and accurate methods. The first prototype of a full waveform hyperspectral Light Detection and Ranging (LiDAR instrument has been developed at the Finnish Geodetic Institute (FGI. The instrument efficiently combines the benefits of passive and active remote sensing sensors. It is able to produce 3D point clouds with spectral information included for every point which offers great potential in the field of remote sensing of environment. This study investigates the performance of the hyperspectral LiDAR instrument in nitrogen estimation. The investigation was conducted by finding vegetation indices sensitive to nitrogen concentration using hyperspectral LiDAR data and validating their performance in nitrogen estimation. The nitrogen estimation was performed by calculating 28 published vegetation indices to ten oat samples grown in different fertilization conditions. Reference data was acquired by laboratory nitrogen concentration analysis. The performance of the indices in nitrogen estimation was determined by linear regression and leave-one-out cross-validation. The results indicate that the hyperspectral LiDAR instrument holds a good capability to estimate plant biochemical parameters such as nitrogen concentration. The instrument holds much potential in various environmental applications and provides a significant improvement to the remote sensing of environment.

Novel Metabolic Attributes of the Genus Cyanothece, Comprising a Group of Unicellular Nitrogen-Fixing Cyanobacteria

Science.gov (United States)

Bandyopadhyay, Anindita; Elvitigala, Thanura; Welsh, Eric; Stöckel, Jana; Liberton, Michelle; Min, Hongtao; Sherman, Louis A.; Pakrasi, Himadri B.

2011-01-01

ABSTRACT The genus Cyanothece comprises unicellular cyanobacteria that are morphologically diverse and ecologically versatile. Studies over the last decade have established members of this genus to be important components of the marine ecosystem, contributing significantly to the nitrogen and carbon cycle. System-level studies of Cyanothece sp. ATCC 51142, a prototypic member of this group, revealed many interesting metabolic attributes. To identify the metabolic traits that define this class of cyanobacteria, five additional Cyanothece strains were sequenced to completion. The presence of a large, contiguous nitrogenase gene cluster and the ability to carry out aerobic nitrogen fixation distinguish Cyanothece as a genus of unicellular, aerobic nitrogen-fixing cyanobacteria. Cyanothece cells can create an anoxic intracellular environment at night, allowing oxygen-sensitive processes to take place in these oxygenic organisms. Large carbohydrate reserves accumulate in the cells during the day, ensuring sufficient energy for the processes that require the anoxic phase of the cells. Our study indicates that this genus maintains a plastic genome, incorporating new metabolic capabilities while simultaneously retaining archaic metabolic traits, a unique combination which provides the flexibility to adapt to various ecological and environmental conditions. Rearrangement of the nitrogenase cluster in Cyanothece sp. strain 7425 and the concomitant loss of its aerobic nitrogen-fixing ability suggest that a similar mechanism might have been at play in cyanobacterial strains that eventually lost their nitrogen-fixing ability. PMID:21972240

Scaling Laws of Nitrogen Soft X-Ray Yields from 1 to 200 kJ Plasma Focus

International Nuclear Information System (INIS)

Akel, M.; Lee, S.

2013-01-01

Numerical experiments are carried out systematically to determine the nitrogen soft x-ray yield for optimized nitrogen plasma focus with storage energy E 0 from 1 kJ to 200 kJ. Scaling laws on nitrogen soft x-ray yield, in terms of storage energies E 0 , peak discharge current I p eak and focus pinch current I p inch were found. It was found that the nitrogen x-ray yields scales on average with y s xr, N= 1.93xE o 1 .21 J (E 0 in kJ) with the scaling showing gradual deterioration as E 0 rises over the range. A more robust scaling is y s xr = 8x10 - 8I 0 3.38 p inch . The optimum nitrogen soft x-ray yield emitted from plasma focus is found to be about 1 kJ for storage energy of 200 kJ. This indicates that nitrogen plasma focus is a good water-window soft x-ray source when properly designed. (author)

Toward a nitrogen footprint calculator for Tanzania

Science.gov (United States)

Hutton, Mary Olivia; Leach, Allison M.; Leip, Adrian; Galloway, James N.; Bekunda, Mateete; Sullivan, Clare; Lesschen, Jan Peter

2017-03-01

We present the first nitrogen footprint model for a developing country: Tanzania. Nitrogen (N) is a crucial element for agriculture and human nutrition, but in excess it can cause serious environmental damage. The Sub-Saharan African nation of Tanzania faces a two-sided nitrogen problem: while there is not enough soil nitrogen to produce adequate food, excess nitrogen that escapes into the environment causes a cascade of ecological and human health problems. To identify, quantify, and contribute to solving these problems, this paper presents a nitrogen footprint tool for Tanzania. This nitrogen footprint tool is a concept originally designed for the United States of America (USA) and other developed countries. It uses personal resource consumption data to calculate a per-capita nitrogen footprint. The Tanzania N footprint tool is a version adapted to reflect the low-input, integrated agricultural system of Tanzania. This is reflected by calculating two sets of virtual N factors to describe N losses during food production: one for fertilized farms and one for unfertilized farms. Soil mining factors are also calculated for the first time to address the amount of N removed from the soil to produce food. The average per-capita nitrogen footprint of Tanzania is 10 kg N yr-1. 88% of this footprint is due to food consumption and production, while only 12% of the footprint is due to energy use. Although 91% of farms in Tanzania are unfertilized, the large contribution of fertilized farms to N losses causes unfertilized farms to make up just 83% of the food production N footprint. In a developing country like Tanzania, the main audiences for the N footprint tool are community leaders, planners, and developers who can impact decision-making and use the calculator to plan positive changes for nitrogen sustainability in the developing world.

Long-term energy efficiency analysis requires solid energy statistics: The case of the German basic chemical industry

International Nuclear Information System (INIS)

Saygin, D.; Worrell, E.; Tam, C.; Trudeau, N.; Gielen, D.J.; Weiss, M.; Patel, M.K.

2012-01-01

Analyzing the chemical industry’s energy use is challenging because of the sector’s complexity and the prevailing uncertainty in energy use and production data. We develop an advanced bottom-up model (PIE-Plus) which encompasses the energy use of the 139 most important chemical processes. We apply this model in a case study to analyze the German basic chemical industry’s energy use and energy efficiency improvements in the period between 1995 and 2008. We compare our results with data from the German Energy Balances and with data published by the International Energy Agency (IEA). We find that our model covers 88% of the basic chemical industry’s total final energy use (including non-energy use) as reported in the German Energy Balances. The observed energy efficiency improvements range between 2.2 and 3.5% per year, i.e., they are on the higher side of the values typically reported in literature. Our results point to uncertainties in the basic chemical industry’s final energy use as reported in the energy statistics and the specific energy consumption values. More efforts are required to improve the quality of the national and international energy statistics to make them useable for reliable monitoring of energy efficiency improvements of the chemical industry. -- Highlights: ► An advanced model was developed to estimate German chemical industry’s energy use. ► For the base year (2000), model covers 88% of the sector’s total final energy use. ► Sector’s energy efficiency improved between 2.2 and 3.5%/yr between 1995 and 2008. ► Improved energy statistics are required for accurate monitoring of improvements.

Improvement of Energy Efficiency and Environmental Safety of Thermal Energy Through the Implementation of Contact Energy Exchange Processes

Science.gov (United States)

Varlamov, Gennadii Borysovich; Romanova, Kateryna Alexandrovna; Nazarova, Iryna; Daschenko, Olga; Kapustiansky, Andry

2017-12-01

Energy efficiency improvement and ecological safety of heat power plants are urgent problems, which require scientifically grounded approaches and solutions. These problems can be solved partly within the presented heat-and-power cycles by including contact energy exchange equipment in the circuits of existing installations. A significant positive effect is obtained in the contact energy exchange installations, such as gas-steam installation `Aquarius' and the contact hydrogen heat generator that also can use hydrogen as a fuel. In these plants, the efficiency increases approximately by 10-12% in comparison with traditional installations, and the concentration of toxic substances, such as nitrogen oxides and carbon monoxide in flue gas can be reduced to 30 mg/m3 and to 5 mg/m3, respectively. Moreover, the plants additionally `generate' the clean water, which can be used for technical purposes.

Utilization of alimentary protein and amino acids in satisfying the nitrogen requirements of monogastric mammals

International Nuclear Information System (INIS)

Pion, R.; Arnal, M.

1976-01-01

The nitrogenous matter in the food of monogastric animals consists mainly of proteins, which are rapidly hydrolized in the intestinal tract when they have left the gastric reservoir. The digestive tube has several roles: it provides for hydrolysis of the food proteins and for a supply of endogenous nitrogen; it enables a certain digestive function to be performed by the intestinal flora and permits the transport of amino acids into the blood, selecting those which are needed for protein synthesis. The digestion products appear mainly in the form of free amino acids in the portal blood. A large proportion of these amino acids is taken up by the liver, so that intense protein synthesis takes place in the latter, coupled with a decrease in catabolism leading to a rhythmic increase in the liver content of proteins and RNA. The labile proteins retained are mainly enzymes, which catabolize the amino acids, and the liver is the site of the catabolism of most of the excess amino acids except those with chain branching. Alimentary deficiencies do not markedly reduce protein synthesis in this organ, since the rate of re-utilization of the amino acids is increased and the liver thus plays a regulatory role. The utilization of amino acids in muscle also follows a certain rhythm, partly connected with feeding, and under hormonal control. The muscle is the seat of catabolism of a large part of the branched chain amino acids, and like the liver it contributes to the energy utilization of amino acids. The rate of utilization of certain essential amino acids can be measured by metabolic criteria, including determination of blood and muscle concentrations and excretion of 14 CO 2 labels in the exhaled air or of 35 S labels in urine. (author)

Biological nitrogen fixation in non-legume plants.

Science.gov (United States)

Santi, Carole; Bogusz, Didier; Franche, Claudine

2013-05-01

Nitrogen is an essential nutrient in plant growth. The ability of a plant to supply all or part of its requirements from biological nitrogen fixation (BNF) thanks to interactions with endosymbiotic, associative and endophytic symbionts, confers a great competitive advantage over non-nitrogen-fixing plants. Because BNF in legumes is well documented, this review focuses on BNF in non-legume plants. Despite the phylogenic and ecological diversity among diazotrophic bacteria and their hosts, tightly regulated communication is always necessary between the microorganisms and the host plant to achieve a successful interaction. Ongoing research efforts to improve knowledge of the molecular mechanisms underlying these original relationships and some common strategies leading to a successful relationship between the nitrogen-fixing microorganisms and their hosts are presented. Understanding the molecular mechanism of BNF outside the legume-rhizobium symbiosis could have important agronomic implications and enable the use of N-fertilizers to be reduced or even avoided. Indeed, in the short term, improved understanding could lead to more sustainable exploitation of the biodiversity of nitrogen-fixing organisms and, in the longer term, to the transfer of endosymbiotic nitrogen-fixation capacities to major non-legume crops.

Evaluating Nitrogen Management Options for Reducing Nitrate Leaching from Northeast U.S. Pastures

Directory of Open Access Journals (Sweden)

William L. Stout

2001-01-01

Full Text Available Substantial amounts of nitrate nitrogen NO3-N can leach from intensively grazed pasture in the northeast U.S. where there is about 30 cm of groundwater recharge, annually. Management options for reducing NO3-N leaching were evaluated for this environment using the Cornell Net Carbohydrate and Protein System Model and a recently developed nitrogen leaching index. Management options utilizing energy supplementation of grazing dairy cows could improve nitrogen efficiency within the cow, but would not necessarily reduce NO3-N leaching at the pasture scale if stocking rate was not controlled. The management option of using white clover to supply nitrogen to the pasture decreased NO3-N leaching, but produced less dry matter yield, which in turn reduced stocking rate. The economic returns of reducing NO3-N with these options need to be evaluated in light of milk prices and commodity and fertilizer nitrogen costs. At current prices and costs, the economic benefit from the energy supplementation options is substantial.

Growth of nitrogen-doped graphene on copper: Multiscale simulations

Science.gov (United States)

Gaillard, P.; Schoenhalz, A. L.; Moskovkin, P.; Lucas, S.; Henrard, L.

2016-02-01

We used multiscale simulations to model the growth of nitrogen-doped graphene on a copper substrate by chemical vapour deposition (CVD). Our simulations are based on ab-initio calculations of energy barriers for surface diffusion, which are complemented by larger scale Kinetic Monte Carlo (KMC) simulations. Our results indicate that the shape of grown doped graphene flakes depends on the temperature and deposition flux they are submitted during the process, but we found no significant effect of nitrogen doping on this shape. However, we show that nitrogen atoms have a preference for pyridine-like sites compared to graphite-like sites, as observed experimentally.

10 CFR 905.17 - What are the requirements for the energy efficiency and/or renewable energy report (EE/RE report...

Science.gov (United States)

2010-01-01

... renewable energy report (EE/RE report) alternative? 905.17 Section 905.17 Energy DEPARTMENT OF ENERGY ENERGY... energy efficiency and/or renewable energy report (EE/RE report) alternative? (a) Requests to submit an EE..., including any requirements for documenting customer energy efficiency and renewable energy activities. (b...

Energy Requirements in Early Life Are Similar for Male and Female Goat Kids

Directory of Open Access Journals (Sweden)

T. F. V. Bompadre

2014-12-01

Full Text Available Little is known about the gender differences in energetic requirements of goats in early life. In this study, we determined the energy requirements for maintenance and gain in intact male, castrated male and female Saanen goat kids using the comparative slaughter technique and provide new data on their body composition and energy efficiency. To determine the energy requirements for maintenance, we studied 21 intact males, 15 castrated males and 18 females (5.0±0.1 kg initial body weight (BW and 23±5 d of age using a split-plot design with the following main factors: three genders (intact males, castrated males, and females and three dry matter intake levels (ad libitum, 75% and 50% of ad libitum intake. A slaughter group included three kids, one for each nutritional plane, of each gender, and all three animals within a group were slaughtered when the ad libitum kid reached 15 kg in BW. Net energy requirements for gain were obtained for 17 intact males, eight castrated males and 15 females (5.1±0.4 kg BW and 23±13 d of age. Animals were fed ad libitum and slaughtered when they reached 5, 10, and 15 kg in BW. A digestion trial was performed with nine kids of each gender to determine digestible energy, metabolizable energy and energy metabolizability of the diet. Our results show no effect of gender on the energy requirements for maintenance and gain, and overall net energy for maintenance was 205.6 kJ/kg0.75 empty body weight gain (EBW (170.3 kJ/kg0.75 BW from 5 to 15 kg BW. Metabolizable energy for maintenance was calculated by iteration, assuming heat production equal to metabolizable energy intake at maintenance, and the result was 294.34 kJ/kg0.75 EBW and km of 0.70. As BW increased from 5 to 15 kg for all genders, the net energy required for gain increased from 9.5 to 12.0 kJ/g EBW gain (EWG, and assuming kg = 0.47, metabolizable energy for gain ranged from 20.2 to 25.5 kJ/g EWG. Our results indicate that it is not necessary to formulate

Origin of the nitrogen over- and understoichiometry in Ti0.5Al0.5N thin films

International Nuclear Information System (INIS)

Baben, Moritz to; Raumann, Leonard; Music, Denis; Schneider, Jochen M

2012-01-01

To identify the origin of the experimentally observed nitrogen over- and understoichiometry in TiAlN thin films, various point defect configurations were studied by ab initio calculations in terms of formation energies, equilibrium volume and elastic moduli. From formation energies and comparison to existing experimental equilibrium volume and elasticity data, it is shown that nitrogen vacancies and metal vacancies are responsible for nitrogen understoichiometry and overstoichiometry, respectively. Irrespective of the type of vacancies, the bulk modulus is decreased by approximately 7% as the nitrogen concentration is increased or decreased by 3 at.%. (paper)

Nitrogen-fixing bacteria in Mediterranean seagrass (Posidonia oceanica) roots

KAUST Repository

Garcias Bonet, Neus

2016-03-09

Biological nitrogen fixation by diazotrophic bacteria in seagrass rhizosphere and leaf epiphytic community is an important source of nitrogen required for plant growth. However, the presence of endophytic diazotrophs remains unclear in seagrass tissues. Here, we assess the presence, diversity and taxonomy of nitrogen-fixing bacteria within surface-sterilized roots of Posidonia oceanica. Moreover, we analyze the nitrogen isotopic signature of seagrass tissues in order to notice atmospheric nitrogen fixation. We detected nitrogen-fixing bacteria by nifH gene amplification in 13 out of the 78 roots sampled, corresponding to 9 locations out of 26 meadows. We detected two different types of bacterial nifH sequences associated with P. oceanica roots, which were closely related to sequences previously isolated from the rhizosphere of a salt marsh cord grass and a putative anaerobe. Nitrogen content of seagrass tissues showed low isotopic signatures in all the sampled meadows, pointing out the atmospheric origin of the assimilated nitrogen by seagrasses. However, this was not related with the presence of endophytic nitrogen fixers, suggesting the nitrogen fixation occurring in rhizosphere and in the epiphytic community could be an important source of nitrogen for P. oceanica. The low diversity of nitrogen-fixing bacteria reported here suggests species-specific relationships between diazotrophs and P. oceanica, revealing possible symbiotic interactions that could play a major role in nitrogen acquisition by seagrasses in oligotrophic environments where they form lush meadows.

Reactions of Ground State Nitrogen Atoms N(4S) with Astrochemically-Relevant Molecules on Interstellar Dusts

Science.gov (United States)

Krim, Lahouari; Nourry, Sendres

2015-06-01

In the last few years, ambitious programs were launched to probe the interstellar medium always more accurately. One of the major challenges of these missions remains the detection of prebiotic compounds and the understanding of reaction pathways leading to their formation. These complex heterogeneous reactions mainly occur on icy dust grains, and their studies require the coupling of laboratory experiments mimicking the extreme conditions of extreme cold and dilute media. For that purpose, we have developed an original experimental approach that combine the study of heterogeneous reactions (by exposing neutral molecules adsorbed on ice to non-energetic radicals H, OH, N...) and a neon matrix isolation study at very low temperatures, which is of paramount importance to isolate and characterize highly reactive reaction intermediates. Such experimental approach has already provided answers to many questions raised about some astrochemically-relevant reactions occurring in the ground state on the surface of dust grain ices in dense molecular clouds. The aim of this new present work is to show the implication of ground state atomic nitrogen on hydrogen atom abstraction reactions from some astrochemically-relevant species, at very low temperatures (3K-20K), without providing any external energy. Under cryogenic temperatures and with high barrier heights, such reactions involving N(4S) nitrogen atoms should not occur spontaneously and require an initiating energy. However, the detection of some radicals species as byproducts, in our solid samples left in the dark for hours at 10K, proves that hydrogen abstraction reactions involving ground state N(4S) nitrogen atoms may occur in solid phase at cryogenic temperatures. Our results show the efficiency of radical species formation stemming from non-energetic N-atoms and astrochemically-relevant molecules. We will then discuss how such reactions, involving nitrogen atoms in their ground states, might be the first key step

Biological effect of nitrogen ion implantation on stevia

International Nuclear Information System (INIS)

Wang Cailian; Shen Mei; Chen Qiufang; Shu Shizhen

1997-10-01

Dry seed of stevia were implanted by 35∼150 keV nitrogen ions with various doses. The biological effect in M 1 was studied. The results showed that nitrogen ion beam was able to induce variation on chromosome structure in root tip cells. The rate of cells with chromosome aberration was increased with ion beam energy and dose added, but there was on significant linear regression relationship between ion dose and aberration rate. The results indicated the seedling height reduced with the increasing of dose for ion beam. The biological effect of nitrogen ion beam on M 1 stevia was lower than that of γ-rays. (6 refs., 1 fig., 4 tabs.)

Marginal abatement cost curve for nitrogen oxides incorporating controls, renewable electricity, energy efficiency, and fuel switching.

Science.gov (United States)

Loughlin, Daniel H; Macpherson, Alexander J; Kaufman, Katherine R; Keaveny, Brian N

2017-10-01

A marginal abatement cost curve (MACC) traces out the relationship between the quantity of pollution abated and the marginal cost of abating each additional unit. In the context of air quality management, MACCs are typically developed by sorting control technologies by their relative cost-effectiveness. Other potentially important abatement measures such as renewable electricity, energy efficiency, and fuel switching (RE/EE/FS) are often not incorporated into MACCs, as it is difficult to quantify their costs and abatement potential. In this paper, a U.S. energy system model is used to develop a MACC for nitrogen oxides (NO x ) that incorporates both traditional controls and these additional measures. The MACC is decomposed by sector, and the relative cost-effectiveness of RE/EE/FS and traditional controls are compared. RE/EE/FS are shown to have the potential to increase emission reductions beyond what is possible when applying traditional controls alone. Furthermore, a portion of RE/EE/FS appear to be cost-competitive with traditional controls. Renewable electricity, energy efficiency, and fuel switching can be cost-competitive with traditional air pollutant controls for abating air pollutant emissions. The application of renewable electricity, energy efficiency, and fuel switching is also shown to have the potential to increase emission reductions beyond what is possible when applying traditional controls alone.

Nitrogen trailer acceptance test report

International Nuclear Information System (INIS)

Kostelnik, A.J.

1996-01-01

This Acceptance Test Report documents compliance with the requirements of specification WHC-S-0249. The equipment was tested according to WHC-SD-WM-ATP-108 Rev.0. The equipment being tested is a portable contained nitrogen supply. The test was conducted at Norco's facility

RECENT PROGRESS OF OXYGEN/NITROGEN SEPARATION USING MEMBRANE TECHNOLOGY

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K. C. CHONG

2016-07-01

Full Text Available The oxygen-enriched air is highly demanded for various industrial applications such as medical, chemical and enhanced combustion processes. The conventional oxygen/nitrogen production is either cryogenic distillation or pressure swing adsorption (PSA. Both of these techniques possess the production capability of 20 to 300 tonnes of oxygen per day and oxygen purity of more than 95%. However, these techniques are energy intensive. Alternatively, membrane technology is an emerging technology in gas separation as it requires low energy consumption and relatively moderate production volume, if compared to the conventional gas production techniques. These advantages have spurred much interest from industries and academics to speed up the commercial viability of the O2/N2 separation via membrane technology. In this review, the conventional and membrane technologies in O2/N2 separation, as well as recent development of membrane fabrication techniques and materials are reviewed. The latest membrane performance in O2/N2 separation is also tabulated and discussed.

First principles investigation of nitrogenated holey graphene

Science.gov (United States)

Xu, Cui-Yan; Dong, Hai-Kuan; Shi, Li-Bin

2018-04-01

The zero band gap problem limits the application of graphene in the field of electronic devices. Opening the band gap of graphene has become a research issue. Nitrogenated holey graphene (NHG) has attracted much attention because of its semiconducting properties. However, the stacking orders and defect properties have not been investigated. In this letter, the structural and stacking properties of NHG are first investigated. We obtain the most stable stacking structure. Then, the band structures for bulk and multilayer NHG are studied. Impact of the strain on the band gaps and bond characteristics is discussed. In addition, we investigate formation mechanism of native defects of carbon vacancy (VC), carbon interstitial (Ci), nitrogen vacancy (VN), and nitrogen interstitial (Ni) in bulk NHG. Formation energies and transition levels of these native defects are assessed.

40 CFR 52.230 - Control strategy and regulations: Nitrogen dioxide.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control strategy and regulations: Nitrogen dioxide. 52.230 Section 52.230 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Control strategy and regulations: Nitrogen dioxide. (a) The requirements of § 52.14(c)(3) of this chapter...

A nutrition mathematical model to account for dietary supply and requirements of energy and nutrients for domesticated small ruminants: the development and evaluation of the Small Ruminant Nutrition System

Directory of Open Access Journals (Sweden)

Luis Orlindo Tedeschi

2008-07-01

Full Text Available A mechanistic model that predicts nutrient requirements and biological values of feeds for sheep (Cornell Net Carbohydrate and Protein System; CNCPS-S was expanded to include goats and the name was changed to the Small Ruminant Nutrition System (SRNS. The SRNS uses animal and environmental factors to predict metabolizable energy (ME and protein, and Ca and P requirements. Requirements for goats in the SRNS are predicted based on the equations developed for CNCPS-S, modified to account for specific requirements of goats, including maintenance, lactation, and pregnancy requirements, and body reserves. Feed biological values are predicted based on carbohydrate and protein fractions and their ruminal fermentation rates, forage, concentrate and liquid passage rates, and microbial growth. The evaluation of the SRNS for sheep using published papers (19 treatment means indicated no mean bias (MB; 1.1 g/100 g and low root mean square prediction error (RMSPE; 3.6 g/100g when predicting dietary organic matter digestibility for diets not deficient in ruminal nitrogen. The SRNS accurately predicted gains and losses of shrunk body weight (SBW of adult sheep (15 treatment means; MB = 5.8 g/d and RMSPE = 30 g/d when diets were not deficient in ruminal nitrogen. The SRNS for sheep had MB varying from -34 to 1 g/d and RSME varying from 37 to 56 g/d when predicting average daily gain (ADG of growing lambs (42 treatment means. The evaluation of the SRNS for goats based on literature data showed accurate predictions for ADG of kids (31 treatment means; RMSEP = 32.5 g/d; r2= 0.85; concordance correlation coefficient, CCC, = 0.91, daily ME intake (21 treatment means; RMSEP = 0.24 Mcal/d g/d; r2 = 0.99; CCC = 0.99, and energy balance (21 treatment means; RMSEP = 0.20 Mcal/d g/d; r2 = 0.87; CCC = 0.90 of goats. In conclusion, the SRNS for sheep can accurately predict dietary organic matter digestibility, ADG of growing lambs and changes in SBW of mature sheep. The SRNS

Using nitrogen concentration and isotopic composition in lichens to spatially assess the relative contribution of atmospheric nitrogen sources in complex landscapes

International Nuclear Information System (INIS)

Pinho, P.; Barros, C.; Augusto, S.; Pereira, M.J.

2017-01-01

Reactive nitrogen (Nr) is an important driver of global change, causing alterations in ecosystem biodiversity and functionality. Environmental assessments require monitoring the emission and deposition of both the amount and types of Nr. This is especially important in heterogeneous landscapes, as different land-cover types emit particular forms of Nr to the atmosphere, which can impact ecosystems distinctively. Such assessments require high spatial resolution maps that also integrate temporal variations, and can only be feasibly achieved by using ecological indicators. Our aim was to rank land-cover types according to the amount and form of emitted atmospheric Nr in a complex landscape with multiple sources of N. To do so, we measured and mapped nitrogen concentration and isotopic composition in lichen thalli, which we then related to land-cover data. Results suggested that, at the landscape scale, intensive agriculture and urban areas were the most important sources of Nr to the atmosphere. Additionally, the ocean greatly influences Nr in land, by providing air with low Nr concentration and a unique isotopic composition. These results have important consequences for managing air pollution at the regional level, as they provide critical information for modeling Nr emission and deposition across regional as well as continental scales. - Highlights: • Which land-cover types are reactive nitrogen sources or sinks at a landscape level? • Nitrogen concentration and isotopic composition were analyzed in lichens. • This allowed determination of the main nitrogen sources: agricultural and urban areas. • Marine sources provided persistent low concentrations of reactive nitrogen. • The typical signature of each source was also determined. - Reactive-nitrogen concentration and isotopic composition in lichens were used to rank Nr sources at a landscape level.

Nitrogen-Doped Holey Graphene as an Anode for Lithium-Ion Batteries with High Volumetric Energy Density and Long Cycle Life.

Science.gov (United States)

Xu, Jiantie; Lin, Yi; Connell, John W; Dai, Liming

2015-12-01

Nitrogen-doped holey graphene (N-hG) as an anode material for lithium-ion batteries has delivered a maximum volumetric capacity of 384 mAh cm(-3) with an excellent long-term cycling life up to 6000 cycles, and as an electrochemical capacitor has delivered a maximum volumetric energy density of 171.2 Wh L(-1) and a volumetric capacitance of 201.6 F cm(-3) . © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Forest fuel reduces the nitrogen load - calculations of nitrogen flows

International Nuclear Information System (INIS)

Burstroem, F.; Johansson, Jan.

1995-12-01

Nitrogen deposition in Sweden has increased strongly during recent decades, particularly in southern Sweden. Nitrogen appears to be largely accumulated in biomass and in the soil. It is therefore desirable to check the accumulation of nitrogen in the forest. The most suitable way of doing this is to remove more nitrogen-rich biomass from the forest, i.e., increase the removal of felling residues from final fellings and cleanings. An ecological condition for intensive removal of fuel is that the ashes are returned. The critical load for nitrogen, CL(N), indicates the level of nitrogen deposition that the forest can withstand without leading to ecological changes. Today, nitrogen deposition is higher than the CL(N) in almost all of Sweden. CL(N) is calculated in such a manner that nitrogen deposition should largely be balanced by nitrogen losses through harvesting during a forest rotation. The value of CL(N) thus largely depends on how much nitrogen is removed with the harvested biomass. When both stems and felling residues are harvested, the CL(N) is about three times higher than in conventional forestry. The increase is directly related to the amount of nitrogen in the removed biofuel. Use of biofuel also causes a certain amount of nitrogen emissions. From the environmental viewpoint there is no difference between the sources of the nitrogen compounds. An analysis of the entire fuel chain shows that, compared with the amount of nitrogen removed from the forest with the fuel, about 5 % will be emitted as nitrogen oxides or ammonia during combustion, and a further ca 5 % during handling and transports. A net amount of about 90 % of biomass nitrogen is removed from the system and becomes inert nitrogen (N 2 ). 60 refs, 3 figs, 4 tabs, 11 appendices

Recent changes in anthropogenic reactive nitrogen compounds

Science.gov (United States)

Andronache, Constantin

2014-05-01

Significant anthropogenic perturbations of the nitrogen cycle are the result of rapid population growth, with mounting need for food and energy production. The increase of reactive nitrogen compounds (such as NOx, HNO3, NH3, and N2O) has a significant impact on human health, environment, and climate. NOx emissions contribute to O3 chemistry, aerosol formation and acidic precipitation. Ammonia is a notable atmospheric pollutant that may deteriorate ecosystems and contribute to respiratory problems. It reacts with acidic gases to form aerosols or is deposited back to ecosystems. The application of fertilizers accounts for most of the N2O production, adding to greenhouse gas emissions. We analyze the change of some reactive nitrogen compounds based on observations, in eastern United States. Results show that the control of NOx and SO2 emissions over the last decades caused a significant decrease of acidic deposition. The nitrate deposition is highest in eastern US, while the ammonium ion concentration is highest in central US regions. Overall, the inorganic nitrogen wet deposition from nitrate and ammonium is enhanced in central, and eastern US. Research shows that sensitive ecosystems in northeastern regions exhibit a slow recovery from the accumulated effects of acidic deposition. Given the growing demand for nitrogen in agriculture and industry, we discuss possible pathways to reduce the impact of excess reactive nitrogen on the environment.

Residential building envelope heat gain and cooling energy requirements

International Nuclear Information System (INIS)

Lam, Joseph C.; Tsang, C.L.; Li, Danny H.W.; Cheung, S.O.

2005-01-01

We present the energy use situation in Hong Kong from 1979 to 2001. The primary energy requirement (PER) nearly tripled during the 23-year period, rising from 195,405 TJ to 572,684 TJ. Most of the PER was used for electricity generation, and the electricity use in residential buildings rose from 7556 TJ (2099 GWh) to 32,799 TJ (9111 GWh), an increase of 334%. Air-conditioning accounted for about 40% of the total residential sector electricity consumption. A total of 144 buildings completed in the month of June during 1992-2001 were surveyed. Energy performance of the building envelopes was investigated in terms of the overall thermal transfer value (OTTV). To develop the appropriated parameters used in OTTV calculation, long-term measured weather data such as ambient temperature (1960-2001), horizontal global solar radiation (1992-2001) and global solar radiation on vertical surfaces (1996-2001) were examined. The OTTV found varied from 27 to 44 W/m 2 with a mean value of 37.7 W/m 2 . Building energy simulation technique using DOE-2.1E was employed to determine the cooling requirements and hence electricity use for building envelope designs with different OTTVs. It was found that cooling loads and electricity use could be expressed in terms of a simple two-parameter linear regression equation involving OTTV

Drying characteristics and nitrogen loss of biogas digestate during drying process

Energy Technology Data Exchange (ETDEWEB)

Maurer, C.; Muller, J. [Hohenheim Univ., Stuttgart (Germany). Inst. of Agricultural Engineering, Tropical and Subtropical Group

2010-07-01

The cost of transporting biogas digestate can be decreased by reducing its water content. However, the digestate emits volatile compounds during drying. This study investigated the drying behaviour and the change of digestate composition. Drying took place in a hybrid solar/waste-heat dryer that used solar energy as well as waste heat from a combined heat and power unit (CHP) and the exhaust air of a microturbine. The experiment involved the use of 60 t of liquid digestate. Climatic conditions were measured inside and outside the drying hall. Dry matter (DM) and organic dry matter (ODM) were also measured on a daily basis. In addition, the energy consumption of waste and solar heat were recorded and related to the quantity of dried feedstock. The total nitrogen, ammonium, phosphate, potassium oxide, magnesium oxide and calcium oxide in the digestate were subjected to chemical analysis before and after the drying process. Losses of nitrogen were calculated. Specific energy consumption depended on the climatic condition. Most of the energy consumption was covered by the waste heat of the CHP. A considerable amount of nitrogen was lost during the drying process.

Energy Efficiency Requirements in Building Codes, Energy Efficiency Policies for New Buildings. IEA Information Paper

Energy Technology Data Exchange (ETDEWEB)

Laustsen, Jens

2008-03-15

The aim of this paper is to describe and analyse current approaches to encourage energy efficiency in building codes for new buildings. Based on this analysis the paper enumerates policy recommendations for enhancing how energy efficiency is addressed in building codes and other policies for new buildings. This paper forms part of the IEA work for the G8 Gleneagles Plan of Action. These recommendations reflect the study of different policy options for increasing energy efficiency in new buildings and examination of other energy efficiency requirements in standards or building codes, such as energy efficiency requirements by major renovation or refurbishment. In many countries, energy efficiency of buildings falls under the jurisdiction of the federal states. Different standards cover different regions or climatic conditions and different types of buildings, such as residential or simple buildings, commercial buildings and more complicated high-rise buildings. There are many different building codes in the world and the intention of this paper is not to cover all codes on each level in all countries. Instead, the paper details different regions of the world and different ways of standards. In this paper we also evaluate good practices based on local traditions. This project does not seek to identify one best practice amongst the building codes and standards. Instead, different types of codes and different parts of the regulation have been illustrated together with examples on how they have been successfully addressed. To complement this discussion of efficiency standards, this study illustrates how energy efficiency can be improved through such initiatives as efficiency labelling or certification, very best practice buildings with extremely low- or no-energy consumption and other policies to raise buildings' energy efficiency beyond minimum requirements. When referring to the energy saving potentials for buildings, this study uses the analysis of recent IEA

[Energy requirements in adolescents playing basketball in Russian Olympic reserve team].

Science.gov (United States)

Martinchik, A N; Baturin, A K; Petukhov, A B; Baeva, V S; Zemlianskaia, T A; Sokolov, A I; Peskova, E V; Tysiachnaia, E M

2003-01-01

The energy expenditure and requirements and dietary intake were studied in basketball players aged 14-16 years during 3 week-training period. The subjects of study were 14 boys and 18 girls as of the members of reserve of Russian Olympic basketball team. The dietary intake was estimated by dietary record of all food consumed within 24 hours last 7 days of training period. The energy expenditure was estimated by registration of time on different physical activity of team and multiplication on physical activity coefficient. The decrease of body mass and body mass index were observed in boys with height 195 cm and more to the end of training period. These tall boys did not consume enough food to satisfy the estimated energy requirement. It is estimated that energy need of tall basketball players is no less then 5000 kcal for boys and 3100 kcal for girls.

Analysis of requirements for accelerating the development of geothermal energy resources in California

Science.gov (United States)

Fredrickson, C. D.

1978-01-01

Various resource data are presented showing that geothermal energy has the potential of satisfying a singificant part of California's increasing energy needs. General factors slowing the development of geothermal energy in California are discussed and required actions to accelerate its progress are presented. Finally, scenarios for developing the most promising prospects in the state directed at timely on-line power are given. Specific actions required to realize each of these individual scenarios are identified.

Multi-component nuclear energy system to meet requirement of self-consistency

International Nuclear Information System (INIS)

Saito, Masaki; Artisyuk, Vladimir; Shmelev, Anotolii; Korovin, Yorii

2000-01-01

Environmental harmonization of nuclear energy technology is considered as an absolutely necessary condition in its future successful development for peaceful use. Establishment of Self-Consistent Nuclear Energy System, that simultaneously meets four requirements - energy production, fuel production, burning of radionuclides and safety, strongly relies on the neutron excess generation. Implementation of external non-fission based neutron sources into fission energy system would open the possibility of approaching Multicomponent Self-Consistent Nuclear Energy System with unlimited fuel resources, zero radioactivity release and high protection against uncontrolled proliferation of nuclear materials. (author)

Symbiosome-like intracellular colonization of cereals and other crop plants by nitrogen-fixing bacteria for reduced inputs of synthetic nitrogen fertilizers.

Science.gov (United States)

Cocking, Edward C; Stone, Philip J; Davey, Michael R

2005-09-01

It has been forecast that the challenge of meeting increased food demand and protecting environmental quality will be won or lost in maize, rice and wheat cropping systems, and that the problem of environmental nitrogen enrichment is most likely to be solved by substituting synthetic nitrogen fertilizers by the creation of cereal crops that are able to fix nitrogen symbiotically as legumes do. In legumes, rhizobia present intracellularly in membrane-bound vesicular compartments in the cytoplasm of nodule cells fix nitrogen endosymbiotically. Within these symbiosomes, membrane-bound vesicular compartments, rhizobia are supplied with energy derived from plant photosynthates and in return supply the plant with biologically fixed nitrogen, usually as ammonia. This minimizes or eliminates the need for inputs of synthetic nitrogen fertilizers. Recently we have demonstrated, using novel inoculation conditions with very low numbers of bacteria, that cells of root meristems of maize, rice, wheat and other major non-legume crops, such as oilseed rape and tomato, can be intracellularly colonized by the non-rhizobial, non-nodulating, nitrogen fixing bacterium,Gluconacetobacter diazotrophicus that naturally occurs in sugarcane.G. diazotrophicus expressing nitrogen fixing (nifH) genes is present in symbiosome-like compartments in the cytoplasm of cells of the root meristems of the target cereals and non-legume crop species, somewhat similar to the intracellular symbiosome colonization of legume nodule cells by rhizobia. To obtain an indication of the likelihood of adequate growth and yield, of maize for example, with reduced inputs of synthetic nitrogen fertilizers, we are currently determining the extent to which nitrogen fixation, as assessed using various methods, is correlated with the extent of systemic intracellular colonization byG. diazotrophicus, with minimal or zero inputs.

Microwave plasma-assisted photoluminescence enhancement in nitrogen-doped ultrananocrystalline diamond film

Directory of Open Access Journals (Sweden)

Yu Lin Liu

2012-06-01

Full Text Available Optical properties and conductivity of nitrogen-doped ultrananocrystal diamond (UNCD films were investigated following treatment with low energy microwave plasma at room temperature. The plasma also generated vacancies in UNCD films and provided heat for mobilizing the vacancies to combine with the impurities, which formed the nitrogen-vacancy defect centers. The generated color centers were distributed uniformly in the samples. The conductivity of nitrogen-doped UNCD films treated by microwave plasma was found to decrease slightly due to the reduced grain boundaries. The photoluminescence emitted by the plasma treated nitrogen-doped UNCD films was enhanced significantly compared to the untreated films.

MEGASTAR: The Meaning of Energy Growth: An Assessment of Systems, Technologies, and Requirements

Science.gov (United States)

1974-01-01

A methodology for the display and analysis of postulated energy futures for the United States is presented. A systems approach that includes the methodology of technology assessment is used to examine three energy scenarios--the Westinghouse Nuclear Electric Economy, the Ford Technical Fix Base Case and a MEGASTAR generated Alternate to the Ford Technical Fix Base Case. The three scenarios represent different paths of energy consumption for the present to the year 2000. Associated with these paths are various mixes of fuels, conversion, distribution, conservation and end-use technologies. MEGASTAR presents the estimated times and unit requirements to supply the fuels, conversion and distribution systems for the postulated end uses for the three scenarios and then estimates the aggregate manpower, materials, and capital requirements needed to develop the energy system described by the particular scenario. The total requirements and the energy subsystems for each scenario are assessed for their primary impacts in the areas of society, the environment, technology and the economy.

Sputtering of solid nitrogen and oxygen by keV hydrogen ions

DEFF Research Database (Denmark)

Ellegaard, O.; Schou, Jørgen; Stenum, B.

1994-01-01

Electronic sputtering of solid nitrogen and oxygen by keV hydrogen ions has been studied at two low-temperature setups. The yield of the sputtered particles has been determined in the energy regime 4-10 keV for H+, H-2+ and H-3+ ions. The yield for oxygen is more than a factor of two larger than...... that for nitrogen. The energy distributions of the sputtered N2 and O2 molecules were measured for hydrogen ions in this energy regime as well. The yields from both solids turn out to depend on the sum of the stopping power of all atoms in the ion. The yield increases as a quadratic function of the stopping power...

Prediction of vapour-liquid and vapour-liquid-liquid equilibria of nitrogen-hydrocarbon mixtures used in J-T refrigerators

Science.gov (United States)

Narayanan, Vineed; Venkatarathnam, G.

2018-03-01

Nitrogen-hydrocarbon mixtures are widely used as refrigerants in J-T refrigerators operating with mixtures, as well as in natural gas liquefiers. The Peng-Robinson equation of state has traditionally been used to simulate the above cryogenic process. Multi parameter Helmholtz energy equations are now preferred for determining the properties of natural gas. They have, however, been used only to predict vapour-liquid equilibria, and not vapour-liquid-liquid equilibria that can occur in mixtures used in cryogenic mixed refrigerant processes. In this paper the vapour-liquid equilibrium of binary mixtures of nitrogen-methane, nitrogen-ethane, nitrogen-propane, nitrogen-isobutane and three component mixtures of nitrogen-methane-ethane and nitrogen-methane-propane have been studied with the Peng-Robinson and the Helmholtz energy equations of state of NIST REFPROP and compared with experimental data available in the literature.

First-principles study on the interaction of nitrogen atom with α–uranium: From surface adsorption to bulk diffusion

International Nuclear Information System (INIS)

Su, Qiulei; Deng, Huiqiu; Xiao, Shifang; Li, Xiaofan; Hu, Wangyu; Ao, Bingyun; Chen, Piheng

2014-01-01

Experimental studies of nitriding on uranium surfaces show that the modified layers provide considerable protection against air corrosion. The bimodal distribution of nitrogen is affected by both its implantation and diffusion, and the diffusion of nitrogen during implantation is also governed by vacancy trapping. In the present paper, nitrogen adsorption, absorption, diffusion, and vacancy trapping on the surface of and in the bulk of α–uranium are studied with a first-principles density functional theory approach and the climbing image nudged elastic band method. The calculated results indicate that, regardless of the nitrogen coverage, a nitrogen atom prefers to reside at the hollow1 site and octahedral (Oct) site on and below the surface, respectively. The lowest energy barriers for on-surface and penetration diffusion occur at a coverage of 1/2 monolayer. A nitrogen atom prefers to occupy the Oct site in bulk α–uranium. High energy barriers are observed during the diffusion between neighboring Oct sites. A vacancy can capture its nearby interstitial nitrogen atom with a low energy barrier, providing a significant attractive nitrogen-vacancy interaction at the trapping center site. This study provides a reference for understanding the nitriding process on uranium surfaces

Energy, material and land requirement of a fusion plant

DEFF Research Database (Denmark)

Schleisner, Liselotte; Hamacher, T.; Cabal, H.

2001-01-01

The energy and material necessary to construct a power plant and the land covered by the plant are indicators for the ‘consumption’ of environment by a certain technology. Based on current knowledge, estimations show that the material necessary to construct a fusion plant will exceed the material...... requirement of a fission plant by a factor of two. The material requirement for a fusion plant is roughly 2000 t/MW and little less than 1000 t/MW for a fission plant. The land requirement for a fusion plant is roughly 300 m2/MW and the land requirement for a fission plant is a little less than 200 m2/MW...... less ‘environment’ for the construction than renewable technologies, especially wind and solar....

Structural and magnetocaloric properties of (Mn,Fe){sub 2}(P,Si) materials with added nitrogen

Energy Technology Data Exchange (ETDEWEB)

Thang, N.V., E-mail: v.t.nguyen-1@tudelft.nl; Miao, X.F., E-mail: X.F.Miao@tudelft.nl; Dijk, N.H. van, E-mail: N.H.vanDijk@tudelft.nl; Brück, E., E-mail: E.H.Bruck@tudelft.nl

2016-06-15

Amongst magnetic materials that exhibit a giant magnetocaloric effect near room temperature, the (Mn,Fe){sub 2}(P,Si) system is one of the most promising candidates for magnetic refrigeration. Although the (Mn,Fe){sub 2}(P,Si) materials hold many advantages, controlling the magnetic entropy change ΔS{sub m}, the adiabatic temperature change ΔT{sub ad}, the thermal hysteresis and the mechanical stability across the ferromagnetic transition requires a delicate tuning of the composition. This work investigates the addition of nitrogen, as an interstitial or substitutional element, as a new parameter to tune the properties of (Mn,Fe){sub 2}(P,Si) materials. We found that the nitrogen addition results in a decrease of the Curie temperature, consistent with the observed increase in the c/a ratio. The introduction of nitrogen in (Mn,Fe){sub 2}(P,Si) materials also results in a strong enhancement of the mechanical stability. - Highlights: • N-doped materials were synthesized by high-energy ball milling and solid-state reactions. • Nitrogen atoms enter the structure both as substitutional and as interstitial element in (Mn,Fe){sub 2}(P,Si) materials. • Nitrogen addition leads to a decrease in the Curie temperature, while improving the mechanical stability and preserving the magnetocaloric properties. • The origin of the increase in the thermal hysteresis by increasing the N content has been investigated by analyzing the XRD data.

Regulators of nonsulfur purple phototrophic bacteria and the interactive control of CO2 assimilation, nitrogen fixation, hydrogen metabolism and energy generation.

Science.gov (United States)

Dubbs, James M; Tabita, F Robert

2004-06-01

For the metabolically diverse nonsulfur purple phototrophic bacteria, maintaining redox homeostasis requires balancing the activities of energy supplying and energy-utilizing pathways, often in the face of drastic changes in environmental conditions. These organisms, members of the class Alphaproteobacteria, primarily use CO2 as an electron sink to achieve redox homeostasis. After noting the consequences of inactivating the capacity for CO2 reduction through the Calvin-Benson-Bassham (CBB) pathway, it was shown that the molecular control of many additional important biological processes catalyzed by nonsulfur purple bacteria is linked to expression of the CBB genes. Several regulator proteins are involved, with the two component Reg/Prr regulatory system playing a major role in maintaining redox poise in these organisms. Reg/Prr was shown to be a global regulator involved in the coordinate control of a number of metabolic processes including CO2 assimilation, nitrogen fixation, hydrogen metabolism and energy-generation pathways. Accumulating evidence suggests that the Reg/Prr system senses the oxidation/reduction state of the cell by monitoring a signal associated with electron transport. The response regulator RegA/PrrA activates or represses gene expression through direct interaction with target gene promoters where it often works in concert with other regulators that can be either global or specific. For the key CO2 reduction pathway, which clearly triggers whether other redox balancing mechanisms are employed, the ability to activate or inactivate the specific regulator CbbR is of paramount importance. From these studies, it is apparent that a detailed understanding of how diverse regulatory elements integrate and control metabolism will eventually be achieved.

Formic acid dimers in a nitrogen matrix

Science.gov (United States)

Lopes, Susy; Fausto, Rui; Khriachtchev, Leonid

2018-01-01

Formic acid (HCOOH) dimers are studied by infrared spectroscopy in a nitrogen matrix and by ab initio calculations. We benefit from the use of a nitrogen matrix where the lifetime of the higher-energy (cis) conformer is very long (˜11 h vs. 7 min in an argon matrix). As a result, in a nitrogen matrix, a large proportion of the cis conformer can be produced by vibrational excitation of the lower-energy (trans) conformer. Three trans-trans, four trans-cis, and three cis-cis dimers are found in the experiments. The spectroscopic information on most of these dimers is enriched compared to the previous studies in an argon matrix. The cis-cis dimers of ordinary formic acid (without deuteration) are reported here for the first time. Several conformational processes are obtained using selective excitation by infrared light, some of them also for the first time. In particular, we report on the formation of cis-cis dimers upon vibrational excitation of trans-cis dimers. Tunneling decays of several dimers have been detected in the dark. The tunneling decay of cis-cis dimers of formic acid as well as the stabilization of cis units in cis-cis dimers is also observed for the first time.

A nitrogen mass balance for California

Science.gov (United States)

Liptzin, D.; Dahlgren, R. A.

2010-12-01

, requires a net influx of N in feed to the state. In terms of exports, the riverine N loads are smaller than many more mesic climates. Because many of the large population centers are on the coast, N discharged directly from wastewater treatment plants into the ocean is almost four times greater than the N discharge of all of the watersheds in the state combined. Gas losses are estimated through a combination of bottom up approaches using field data, emissions inventories, and numerical models. The largest uncertainties are in emissions of N2 and NH3. Calculated by difference, groundwater N loading represents the largest loss term in the mass balance. Contamination of groundwater with nitrates is a serious concern in many areas of the state. Given the long residence time of groundwater in many aquifers like the Central Valley the current and past N inputs to groundwater pose a hazard to drinking water supplies for decades to come. These calculations along with the analysis of management and policy tools will help elucidate the spatial location or activities that would be best to target to reduce the negative consequences of human alteration of the nitrogen cycle.

CoM(M=Fe,Cu,Ni)-embedded nitrogen-enriched porous carbon framework for efficient oxygen and hydrogen evolution reactions

Science.gov (United States)

Feng, Xiaogeng; Bo, Xiangjie; Guo, Liping

2018-06-01

Rational synthesis and development of earth-abundant materials with efficient electrocatalytic activity and stability for water splitting is a critical but challenging step for sustainable energy application. Herein, a family of bimetal (CoFe, CoCu, CoNi) embedded nitrogen-doped carbon frameworks is developed through a facile and simple thermal conversion strategy of metal-doped zeolitic imidazolate frameworks. Thanks to collaborative superiorities of abundant M-N-C species, modulation action of secondary metal, cobalt-based electroactive phases, template effect of MOFs and unique porous structure, bimetal embedded nitrogen-doped carbon frameworks materials manifest good oxygen and hydrogen evolution catalytic activity. Especially, after modulating the species and molar ratio of metal sources, optimal Co0.75Fe0.25 nitrogen-doped carbon framework catalyst just requires a low overpotential of 303 mV to achieve 10 mA cm-2 with a low Tafel slope (39.49 mV dec-1) for oxygen evolution reaction, which even surpasses that of commercial RuO2. In addition, the optimal catalyst can function as an efficient bifunctional electrocatalyst for overall water splitting with satisfying activity and stability. This development offers an attractive direction for the rational design and fabrication of porous carbon materials for electrochemical energy applications.

Nanopores creation in boron and nitrogen doped polycrystalline graphene: A molecular dynamics study

Science.gov (United States)

Izadifar, Mohammadreza; Abadi, Rouzbeh; Nezhad Shirazi, Ali Hossein; Alajlan, Naif; Rabczuk, Timon

2018-05-01

In the present paper, molecular dynamic simulations have been conducted to investigate the nanopores creation on 10% of boron and nitrogen doped polycrystalline graphene by silicon and diamond nanoclusters. Two types of nanoclusters based on silicon and diamond are used to investigate their effect for the fabrication of nanopores. Therefore, three different diameter sizes of the clusters with five kinetic energies of 10, 50, 100, 300 and 500 eV/atom at four different locations in boron or nitrogen doped polycrystalline graphene nanosheets have been perused. We also study the effect of 3% and 6% of boron doped polycrystalline graphene with the best outcome from 10% of doping. Our results reveal that the diamond cluster with diameter of 2 and 2.5 nm fabricates the largest nanopore areas on boron and nitrogen doped polycrystalline graphene, respectively. Furthermore, the kinetic energies of 10 and 50 eV/atom can not fabricate nanopores in some cases for silicon and diamond clusters on boron doped polycrystalline graphene nanosheets. On the other hand, silicon and diamond clusters fabricate nanopores for all locations and all tested energies on nitrogen doped polycrystalline graphene. The area sizes of nanopores fabricated by silicon and diamond clusters with diameter of 2 and 2.5 nm are close to the actual area size of the related clusters for the kinetic energy of 300 eV/atom in all locations on boron doped polycrystalline graphene. The maximum area and the average maximum area of nanopores are fabricated by the kinetic energy of 500 eV/atom inside the grain boundary at the center of the nanosheet and in the corner of nanosheet with diameters of 2 and 3 nm for silicon and diamond clusters on boron and nitrogen doped polycrystalline graphene.

Requirements of Integrated Design Teams While Evaluating Advanced Energy Retrofit Design Options in Immersive Virtual Environments

Directory of Open Access Journals (Sweden)

Xue Yang

2015-12-01

Full Text Available One of the significant ways to save energy use in buildings is to implement advanced energy retrofits in existing buildings. Improving energy performance of buildings through advanced energy retrofitting requires a clear understanding of the cost and energy implications of design alternatives from various engineering disciplines when different retrofit options are considered. The communication of retrofit design alternatives and their energy implications is essential in the decision-making process, as it affects the final retrofit selections and hence the energy efficiency of the retrofitted buildings. The objective of the research presented here was to identify a generic list of information requirements that are needed to be shared and collectively analyzed by integrated design teams during advanced energy retrofit design review meetings held in immersive settings. While identifying such requirements, the authors used an immersive environment based iterative requirements elicitation approach. The technology was used as a means to better identify the information requirements of integrated design teams to be analyzed as a group. This paper provides findings on information requirements of integrated design teams when evaluating retrofit options in immersive virtual environments. The information requirements were identified through interactions with sixteen experts in design and energy modeling domain, and validated with another group of participants consisting of six design experts who were experienced in integrated design processes. Industry practitioners can use the findings in deciding on what information to share with integrated design team members during design review meetings that utilize immersive virtual environments.

Critical and precious materials consumption and requirement in wind energy system in the EU 27

International Nuclear Information System (INIS)

Kim, Junbeum; Guillaume, Bertrand; Chung, Jinwook; Hwang, Yongwoo

2015-01-01

Graphical abstract: Critical and precious materials requirement in the wind energy system in the EU 27 by 2020. - Highlights: • The critical and precious materials consumption were calculated in wind energy system in the EU 27. • The future requirement of critical and precious materials was estimated in the EU 27 by 2020. • Fluorspar, silver, magnesium, indium, gold and tantalum are the mainly used and required materials. • This research approach could be applied to other industrial sectors as well as other renewable technology. - Abstract: Critical materials as well as rare earth elements and precious metals such as platinum, gold and silver are used significantly for computer hard disk drives, mobile phones, hybrid electric vehicles, batteries, renewable energy system and many other applications. It is therefore important to quantify and estimate both current stocks and flows of such materials, as well as future requirement for industries and economies. In this study, which is focused on wind energy system in the European Union (EU) 27, the current consumption and future requirement of critical and precious materials were calculated and estimated using the wind power production dataset from ecoinvent and data from National Renewable Energy Action Plan (NREAP). It is shown that fluorspar has been the most consumed material to date, and will probably be the most required material in the future. Among other critical and valuable materials, the main materials used for current wind energy system are silver, magnesium, indium, gold and tantalum. These materials will also be required significantly by 2020 for the wind energy system in the EU 27. It is argued that these results should be connected to the future energy and material policy and management

Stoichiometric carbon nitride synthesized by ion beam sputtering and post nitrogen ion implantation

International Nuclear Information System (INIS)

Valizadeh, R.; Colligon, J.S.; Katardiev, I.V.; Faunce, C.A.; Donnelly, S.E.

1998-01-01

Full text: Carbon nitride films have been deposited on Si (100) by ion beam sputtering a vitreous graphite target with nitrogen and argon ions with and without concurrent N2 ion bombardment at room temperature. The sputtering beam energy was 1000 eV and the assisted beam energy was 300 eV with ion / atom arrival ratio ranging from 0.5 to 5. The carbon nitride films were deposited both as single layer directly on silicon substrate and as multilayer between two layers of stoichiometric amorphous silicon nitride and polycrystalline titanium nitride. The deposited films were implanted ex-situ with 30 keV nitrogen ions with various doses ranging from 1E17 to 4E17 ions.cm -2 and 2 GeV xenon ion with a dose of 1E12 ions.cm -2 . The nitrogen concentration of the films was measured with Rutherford Backscattering (RBS), Secondary Neutral Mass Spectrometry (SNMS) and Parallel Electron Energy Loss Spectroscopy (PEELS). The nitrogen concentration for as deposited sample was 34 at% and stoichiometric carbon nitride C 3 N 4 was achieved by post nitrogen implantation of the multi-layered films. Post bombardment of single layer carbon nitride films lead to reduction in the total nitrogen concentration. Carbon K edge structure obtained from PEELS analysis suggested that the amorphous C 3 N 4 matrix was predominantly sp 2 bonded. This was confirmed by Fourier Transforrn Infra-Red Spectroscopy (FTIR) analysis of the single CN layer which showed the nitrogen was mostly bonded with carbon in nitrile (C≡N) and imine (C=N) groups. The microstructure of the film was determined by Transmission Electron Microscopy (TEM) which indicated that the films were amorphous

Peptide-chaperone-directed transdermal protein delivery requires energy.

Science.gov (United States)

Ruan, Renquan; Jin, Peipei; Zhang, Li; Wang, Changli; Chen, Chuanjun; Ding, Weiping; Wen, Longping

2014-11-03

The biologically inspired transdermal enhanced peptide TD1 has been discovered to specifically facilitate transdermal delivery of biological macromolecules. However, the biological behavior of TD1 has not been fully defined. In this study, we find that energy is required for the TD1-mediated transdermal protein delivery through rat and human skins. Our results show that the permeation activity of TD1-hEGF, a fusion protein composed of human epidermal growth factor (hEGF) and the TD1 sequence connected with a glycine-serine linker (GGGGS), can be inhibited by the energy inhibitor, rotenone or oligomycin. In addition, adenosine triphosphate (ATP), the essential energetic molecule in organic systems, can effectively facilitate the TD1 directed permeation of the protein-based drug into the skin in a dose-dependent fashion. Our results here demonstrate a novel energy-dependent permeation process during the TD1-mediated transdermal protein delivery that could be valuable for the future development of promising new transdermal drugs.

Improved generation of single nitrogen-vacancy centers in diamond by ion implantation

Energy Technology Data Exchange (ETDEWEB)

Naydenov, Boris; Beck, Johannes; Steiner, Matthias; Balasubramanian, Gopalakrishnan; Jelezko, Fedor; Wrachtrup, Joerg [3. Institute of Physics, University of Stuttgart (Germany); Richter, Vladimir; Kalish, Rafi [Solid State Institute, Technion City, Haifa (Israel); Achard, Jocelyn [Laboratoire d' Ingenieurie des Materiaux et des Hautes Pressions, CNRS, Villetaneuse (France)

2010-07-01

Nitrogen-vacancy (NV) centers in diamond have recently attracted the attention of many research groups due to their possible application as quantum bits (qubits), ultra low magnetic field sensors and single photon sources. These color centers can be produced by nitrogen ion implantation, although the yield is usually below 5 % at low ion energies. Here we report an increase of the NV production efficiency by subsequently implanting carbon ions in the area of implanted nitrogen ions. This method improves the production yield by more than 50 %. We also show that very low nitrogen concentration (below 0.1 ppb) in diamond can be determined by converting the intrinsic nitrogen atoms to single NV centers and detecting the latter using a confocal microscope.

Environmental costs of fossil fuel energy production

International Nuclear Information System (INIS)

Riva, A.; Trebeschi, C.

1997-01-01

The costs of environmental impacts caused by fossil fuel energy production are external to the energy economy and normally they are not reflected in energy prices. To determine the environmental costs associated with an energy source a detailed analysis of all environmental impacts of the complete energy cycle is required. The economic evaluation of environmental damages is presented caused by atmospheric emissions produced by fossil fuel combustion for different uses. Considering the emission factors of sulphur oxides, nitrogen oxides, dust and carbon dioxide and the economic evaluation of their environmental damages reported in literature, a range of environmental costs associated with different fossil fuels and technologies is presented. A comparison of environmental costs resulting from atmospheric emissions produced by fossil-fuel combustion for energy production shows that natural gas has a significantly higher environmental value than other fossil fuels. (R.P.)

Nitrogen availability for nitrogen fixing cyanobacteria upon growth ...

African Journals Online (AJOL)

The filamentous cyanobacterium Nostoc PCC 7120 is able to convert dinitrogen to ammonia in the absence of combined nitrogen. The expression of 20% of coding sequences from all major metabolic categories was examined in nitrogen fixing and non-nitrogen fixing growth conditions. The expression data were correlated ...

Behaviour of uranium dioxide in liquid nitrogen tetraoxide

International Nuclear Information System (INIS)

Kobets, L.V.; Klavsut', G.N.; Dolgov, V.M.

1983-01-01

Interaction kinetics of uranium dioxide with liquid nitrogen tetroxide at 25-150 deg C has been studied. It is shown that in the temperature range studied NO[UO 2 (NO 3 ) 3 ] is the final product of the reaction. With the increase of specific surface of uranium dioxide and with the temperature increase the degree of oxide transformation increases. Uranium dioxide-liquid N 2 O 4 interaction proceeds in the diffusion region. Seeming activation energies and rate constants of the mentioned processes are calculated. Effect of nitrogen trioxide additions on transformation kinetics is considered

Fragmentation of nitrogen-14 nuclei at 2.1 Gev per nucleon.

Science.gov (United States)

Heckman, H. H.; Greiner, D. E.; Lindstrom, P. J.; Bieser, F. S.

1971-01-01

An experiment has been carried out at the bevatron on the nuclear fragmentation of nitrogen-14 ions at an energy of 2.1 billion electron volts (Gev) per nucleon. Because of the near equality of the velocities of the nitrogen-14 beam and the fragmentation products at an angle of 0 deg, we find it possible to identify the nuclear fragments isotopically.

Experimental identification of nitrogen-vacancy complexes in nitrogen implanted silicon

Science.gov (United States)

Adam, Lahir Shaik; Law, Mark E.; Szpala, Stanislaw; Simpson, P. J.; Lawther, Derek; Dokumaci, Omer; Hegde, Suri

2001-07-01

Nitrogen implantation is commonly used in multigate oxide thickness processing for mixed signal complementary metal-oxide-semiconductor and System on a Chip technologies. Current experiments and diffusion models indicate that upon annealing, implanted nitrogen diffuses towards the surface. The mechanism proposed for nitrogen diffusion is the formation of nitrogen-vacancy complexes in silicon, as indicated by ab initio studies by J. S. Nelson, P. A. Schultz, and A. F. Wright [Appl. Phys. Lett. 73, 247 (1998)]. However, to date, there does not exist any experimental evidence of nitrogen-vacancy formation in silicon. This letter provides experimental evidence through positron annihilation spectroscopy that nitrogen-vacancy complexes indeed form in nitrogen implanted silicon, and compares the experimental results to the ab initio studies, providing qualitative support for the same.

Few-layer MoS2 as nitrogen protective barrier

Science.gov (United States)

Akbali, B.; Yanilmaz, A.; Tomak, A.; Tongay, S.; Çelebi, C.; Sahin, H.

2017-10-01

We report experimental and theoretical investigations of the observed barrier behavior of few-layer MoS2 against nitrogenation. Owing to its low-strength shearing, low friction coefficient, and high lubricity, MoS2 exhibits the demeanor of a natural N-resistant coating material. Raman spectroscopy is done to determine the coating capability of MoS2 on graphene. Surface morphology of our MoS2/graphene heterostructure is characterized by using optical microscopy, scanning electron microscopy, and atomic force microscopy. In addition, density functional theory-based calculations are performed to understand the energy barrier performance of MoS2 against nitrogenation. The penetration of nitrogen atoms through a defect-free MoS2 layer is prevented by a very high vertical diffusion barrier, indicating that MoS2 can serve as a protective layer for the nitrogenation of graphene. Our experimental and theoretical results show that MoS2 material can be used both as an efficient nanocoating material and as a nanoscale mask for selective nitrogenation of graphene layer.

An online tool for tracking soil nitrogen

Science.gov (United States)

Wang, J.; Umar, M.; Banger, K.; Pittelkow, C. M.; Nafziger, E. D.

2016-12-01

Near real-time crop models can be useful tools for optimizing agricultural management practices. For example, model simulations can potentially provide current estimates of nitrogen availability in soil, helping growers decide whether more nitrogen needs to be applied in a given season. Traditionally, crop models have been used at point locations (i.e. single fields) with homogenous soil, climate and initial conditions. However, nitrogen availability across fields with varied weather and soil conditions at a regional or national level is necessary to guide better management decisions. This study presents the development of a publicly available, online tool that automates the integration of high-spatial-resolution forecast and past weather and soil data in DSSAT to estimate nitrogen availability for individual fields in Illinois. The model has been calibrated with field experiments from past year at six research corn fields across Illinois. These sites were treated with applications of different N fertilizer timings and amounts. The tool requires minimal management information from growers and yet has the capability to simulate nitrogen-water-crop interactions with calibrated parameters that are more appropriate for Illinois. The results from the tool will be combined with incoming field experiment data from 2016 for model validation and further improvement of model's predictive accuracy. The tool has the potential to help guide better nitrogen management practices to maximize economic and environmental benefits.

Energy requirements for maintenance and growth of male saanen goat kids.

Science.gov (United States)

Medeiros, A N; Resende, K T; Teixeira, I A M A; Araújo, M J; Yáñez, E A; Ferreira, A C D

2014-09-01

The aim of study was to determine the energy requirements for maintenance and growth of forty-one Saanen, intact male kids with initial body weight (BW) of 5.12±0.19 kg. The baseline (BL) group consisted of eight kids averaging 5.46±0.18 kg BW. An intermediate group consisted of six kids, fed for ad libitum intake, that were slaughtered when they reached an average BW of 12.9±0.29 kg. The remaining kids (n = 27) were randomly allocated into nine slaughter groups (blocks) of three animals distributed among three amounts of dry matter intake (DMI; ad libitum and restricted to 70% or 40% of ad libitum intake). Animals in a group were slaughtered when the ad libitum-treatment kid in the group reached 20 kg BW. In a digestibility trial, 21 kids (same animals of the comparative slaughter) were housed in metabolic cages and used in a completely randomized design to evaluate the energetic value of the diet at different feed intake levels. The net energy for maintenance (NEm) was 417 kJ/kg(0.75) of empty BW (EBW)/d, while the metabolizable energy for maintenance (MEm) was 657 kJ/kg(0.75) of EBW/d. The efficiency of ME use for NE maintenance (km) was 0.64. Body fat content varied from 59.91 to 92.02 g/kg of EBW while body energy content varied from 6.37 to 7.76 MJ/kg of EBW, respectively, for 5 and 20 kg of EBW. The net energy for growth (NEg) ranged from 7.4 to 9.0 MJ/kg of empty weight gain by day at 5 and 20 kg BW, respectively. This study indicated that the energy requirements in goats were lower than previously published requirements for growing dairy goats.

76 FR 52283 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Control of Nitrogen...

Science.gov (United States)

2011-08-22

... Promulgation of Air Quality Implementation Plans; Pennsylvania; Control of Nitrogen Oxides Emissions From Glass... revisions pertain to the control of nitrogen oxide (NO X ) emissions from glass melting furnaces. EPA is..., Nitrogen dioxide, Ozone, Particulate matter, Reporting and recordkeeping requirements. Dated: August 8...

Development of a global electricity supply model and investigation of electricity supply by renewable energies with a focus on energy storage requirements for Europe

Energy Technology Data Exchange (ETDEWEB)

Troendle, Tobias Wolfgang

2014-12-12

Electricity supply at present requires about 38% of the global primary energy demand and it is likely to rise further in the coming decades. Facing major problems, such as limited resources of fuels and an ongoing anthropogenic climate change, a sustainable electricity supply based on renewable energies is absolutely vital. Wind and solar power will play an extensive role in future supplies but require energy storage capacities to meet electricity demand. To investigate the relationship of power plant mix and required energy storage capacity, a computer model based on global weather data has been developed to enable the simulation of electricity supply scenarios by up to ten different power plant types for various regions. The focus of the investigation has been on the energy storage requirements of an electricity supply for Europe by wind and solar power. The minimum required energy storage capacity for a totally weather dependent electricity supply occurs at a ratio of 30% wind and 70% photovoltaic (PV) power plant capacity installed. Thus, the required energy storage capacity rises from a transition of to-day's electricity supply to the afore-mentioned 100% renewable wind and PV scenario exponentially to about 150 TWh (3.8% of the annual electricity demand). The installation of additional excess wind and PV power plant capacity was seen to be an efficient way to reduce the required energy storage. Already 10% excess capacity lead to a reduction by 50% of the required storage capacity. To use different storage technologies in an optimised way in terms of storage capacity and efficiency, the storage tasks can be separated into a daily and a seasonal usage. While the seasonal storage capacity has to be about two orders of magnitude larger than the required capacity of the storage for the daily cycle, the sum of stored energy during one year is almost equal for the long and short time storage. In summary, an electricity supply by wind and PV power was shown to

Development of a global electricity supply model and investigation of electricity supply by renewable energies with a focus on energy storage requirements for Europe

International Nuclear Information System (INIS)

Troendle, Tobias Wolfgang

2014-01-01

Electricity supply at present requires about 38% of the global primary energy demand and it is likely to rise further in the coming decades. Facing major problems, such as limited resources of fuels and an ongoing anthropogenic climate change, a sustainable electricity supply based on renewable energies is absolutely vital. Wind and solar power will play an extensive role in future supplies but require energy storage capacities to meet electricity demand. To investigate the relationship of power plant mix and required energy storage capacity, a computer model based on global weather data has been developed to enable the simulation of electricity supply scenarios by up to ten different power plant types for various regions. The focus of the investigation has been on the energy storage requirements of an electricity supply for Europe by wind and solar power. The minimum required energy storage capacity for a totally weather dependent electricity supply occurs at a ratio of 30% wind and 70% photovoltaic (PV) power plant capacity installed. Thus, the required energy storage capacity rises from a transition of to-day's electricity supply to the afore-mentioned 100% renewable wind and PV scenario exponentially to about 150 TWh (3.8% of the annual electricity demand). The installation of additional excess wind and PV power plant capacity was seen to be an efficient way to reduce the required energy storage. Already 10% excess capacity lead to a reduction by 50% of the required storage capacity. To use different storage technologies in an optimised way in terms of storage capacity and efficiency, the storage tasks can be separated into a daily and a seasonal usage. While the seasonal storage capacity has to be about two orders of magnitude larger than the required capacity of the storage for the daily cycle, the sum of stored energy during one year is almost equal for the long and short time storage. In summary, an electricity supply by wind and PV power was shown to

Novel metabolic attributes of the genus cyanothece, comprising a group of unicellular nitrogen-fixing Cyanothece.

Science.gov (United States)

Bandyopadhyay, Anindita; Elvitigala, Thanura; Welsh, Eric; Stöckel, Jana; Liberton, Michelle; Min, Hongtao; Sherman, Louis A; Pakrasi, Himadri B

2011-01-01

The genus Cyanothece comprises unicellular cyanobacteria that are morphologically diverse and ecologically versatile. Studies over the last decade have established members of this genus to be important components of the marine ecosystem, contributing significantly to the nitrogen and carbon cycle. System-level studies of Cyanothece sp. ATCC 51142, a prototypic member of this group, revealed many interesting metabolic attributes. To identify the metabolic traits that define this class of cyanobacteria, five additional Cyanothece strains were sequenced to completion. The presence of a large, contiguous nitrogenase gene cluster and the ability to carry out aerobic nitrogen fixation distinguish Cyanothece as a genus of unicellular, aerobic nitrogen-fixing cyanobacteria. Cyanothece cells can create an anoxic intracellular environment at night, allowing oxygen-sensitive processes to take place in these oxygenic organisms. Large carbohydrate reserves accumulate in the cells during the day, ensuring sufficient energy for the processes that require the anoxic phase of the cells. Our study indicates that this genus maintains a plastic genome, incorporating new metabolic capabilities while simultaneously retaining archaic metabolic traits, a unique combination which provides the flexibility to adapt to various ecological and environmental conditions. Rearrangement of the nitrogenase cluster in Cyanothece sp. strain 7425 and the concomitant loss of its aerobic nitrogen-fixing ability suggest that a similar mechanism might have been at play in cyanobacterial strains that eventually lost their nitrogen-fixing ability. The unicellular cyanobacterial genus Cyanothece has significant roles in the nitrogen cycle in aquatic and terrestrial environments. Cyanothece sp. ATCC 51142 was extensively studied over the last decade and has emerged as an important model photosynthetic microbe for bioenergy production. To expand our understanding of the distinctive metabolic capabilities of

Evaluation of the energy required for constructing and operating a fusion power plant

International Nuclear Information System (INIS)

Buende, R.

1982-09-01

The energy required for constructing and operating a tokamak fusion power plant is appraised with respect to the energy output during the lifetime of the plant. A harvesting factor is deduced as a relevant figure of energetic merit and is used for a comparison between fusion, fission, and coal-fired power plants. Because fusion power plants involve considerable uncertainties the comparison is supplemented by a sensitivity analysis. In comparison with Light Water Reactor plants fusion power plants appear to be rather favourable in this respect. The energy required for providing the fuel is relatively low for fusion plants, thus overcompensating the considerable higher amount of energy necessary for constructing the fusion power plant. (orig.)

Regulatory Drivers of Multimedia Reactive Nitrogen Research (Invited)

Science.gov (United States)

Shaw, S. L.; Knipping, E.; Kumar, N.

2010-12-01

The presence of nitrogenous compounds can impact biogeochemical processes in the atmosphere, oceans and freshwater, and land surfaces. As a result, a number of regulations exist that are intended to control the amount and forms of nitrogen present in the environment. These range from the newly proposed Transport Rule, both the primary and secondary National Ambient Air Quality Standards (NAAQS) for nitrogen oxide targeted at ozone and particulate matter formation and nitrogen deposition, and waterbody requirements such as the Total Maximum Daily Load. This talk will cover a subset of research activities at EPRI that inform environmental nitrogen concerns. A multimedia modeling framework has facilitated effect studies of atmospheric loadings on ecosystems. Improvements in emissions estimates, such as for mobile sources, suggest large current underestimates that will substantially impact air quality modeling of nitrogen oxides. Analyses of wintertime nitrate formation in the northern U.S. are demonstrating the roles of NH3 and NOx in particle formation there. Novel measurements of power plant stack emissions suggest operating configurations can influence the isotopic composition of emitted NOx. Novel instruments for ambient measurements of nitrogen, and suggestions for improved deposition estimates, are being developed. EPRI results suggest that multimedia solutions across multiple economic sectors, such as electrification of a wide variety of engines and water quality treatment and trading, have the potential to improve environmental quality effectively.

Removal of sulfur and nitrogen containing pollutants from discharge gases

Energy Technology Data Exchange (ETDEWEB)

Joubert, James I. (Pittsburgh, PA)

1986-01-01

Oxides of sulfur and of nitrogen are removed from waste gases by reaction with an unsupported copper oxide powder to form copper sulfate. The resulting copper sulfate is dissolved in water to effect separation from insoluble mineral ash and dried to form solid copper sulfate pentahydrate. This solid sulfate is thermally decomposed to finely divided copper oxide powder with high specific surface area. The copper oxide powder is recycled into contact with the waste gases requiring cleanup. A reducing gas can be introduced to convert the oxide of nitrogen pollutants to nitrogen.

Removal of sulfur and nitrogen containing pollutants from discharge gases

Energy Technology Data Exchange (ETDEWEB)

Joubert, J.I.

1985-02-08

Oxides of sulfur and of nitrogen are removed from waste gases by reaction with an unsupported copper oxide powder to form copper sulfate. The resulting copper sulfate is dissolved in water to effect separation from insoluble mineral ash and dried to form solid copper sulfate pentahydrate. This solid sulfate is thermally decomposed to finely divided copper oxide powder with high specific surface area. The copper oxide powder is recycled into contact with the waste gases requiring cleanup. A reducing gas can be introduced to convert the oxide of nitrogen pollutants to nitrogen.

Intra-specific diet shift in manila clams (Ruditapes philippinarum) as revealed by carbon and nitrogen stable isotopes and fatty acid biomarker

Science.gov (United States)

Suh, Y.; Shin, K.

2011-12-01

Manila clams sampled in Seonjae Island, Korea with shell lengths (SL) below 19.76 mm in average showed a significantly depleted carbon and nitrogen isotope values (Pcultured in IFHRI. The result of fatty acid composition of manila clams in relation to size or growth rate suggests that fast growing clams would have rapid metabolism of fatty acids not required by the animals and an accumulation of the essential fatty acids (PUFA). In addition, their higher energy requirement and more active state of development would further diminish lipid reserve of the species.

Energy requirements during sponge cake baking: Experimental and simulated approach

International Nuclear Information System (INIS)

Ureta, M. Micaela; Goñi, Sandro M.; Salvadori, Viviana O.; Olivera, Daniela F.

2017-01-01

Highlights: • Sponge cake energy consumption during baking was studied. • High oven temperature and forced convection mode favours oven energy savings. • Forced convection produced higher weight loss thus a higher product energy demand. • Product energy demand was satisfactorily estimated by the baking model applied. • The greatest energy efficiency corresponded to the forced convection mode. - Abstract: Baking is a high energy demanding process, which requires special attention in order to know and improve its efficiency. In this work, energy consumption associated to sponge cake baking is investigated. A wide range of operative conditions (two ovens, three convection modes, three oven temperatures) were compared. Experimental oven energy consumption was estimated taking into account the heating resistances power and a usage factor. Product energy demand was estimated from both experimental and modeling approaches considering sensible and latent heat. Oven energy consumption results showed that high oven temperature and forced convection mode favours energy savings. Regarding product energy demand, forced convection produced faster and higher weight loss inducing a higher energy demand. Besides, this parameter was satisfactorily estimated by the baking model applied, with an average error between experimental and simulated values in a range of 8.0–10.1%. Finally, the energy efficiency results indicated that it increased linearly with the effective oven temperature and that the greatest efficiency corresponded to the forced convection mode.

Energy required to pinch a DNA plectoneme

Science.gov (United States)

Barde, Céline; Destainville, Nicolas; Manghi, Manoel

2018-03-01

DNA supercoiling plays an important role from a biological point of view. One of its consequences at the supramolecular level is the formation of DNA superhelices named plectonemes. Normally separated by a distance on the order of 10 nm, the two opposite double strands of a DNA plectoneme must be brought closer if a protein or protein complex implicated in genetic regulation is to be bound simultaneously to both strands, as if the plectoneme was locally pinched. We propose an analytic calculation of the energetic barrier, of elastic nature, required to bring closer the two loci situated on the opposed double strands. We examine how this energy barrier scales with the DNA supercoiling. For physically relevant values of elastic parameters and of supercoiling density, we show that the energy barrier is in the kBT range under physiological conditions, thus demonstrating that the limiting step to loci encounter is more likely the preceding plectoneme slithering bringing the two loci side by side.

Modelling of capital requirements in the energy sector: capital market access. Final memorandum

Energy Technology Data Exchange (ETDEWEB)

1978-04-01

Formal modelling techniques for analyzing the capital requirements of energy industries have been performed at DOE. A survey has been undertaken of a number of models which forecast energy-sector capital requirements or which detail the interactions of the energy sector and the economy. Models are identified which can be useful as prototypes for some portion of DOE's modelling needs. The models are examined to determine any useful data bases which could serve as inputs to an original DOE model. A selected group of models are examined which can comply with the stated capabilities. The data sources being used by these models are covered and a catalog of the relevant data bases is provided. The models covered are: capital markets and capital availability models (Fossil 1, Bankers Trust Co., DRI Macro Model); models of physical capital requirements (Bechtel Supply Planning Model, ICF Oil and Gas Model and Coal Model, Stanford Research Institute National Energy Model); macroeconomic forecasting models with input-output analysis capabilities (Wharton Annual Long-Term Forecasting Model, Brookhaven/University of Illinois Model, Hudson-Jorgenson/Brookhaven Model); utility models (MIT Regional Electricity Model-Baughman Joskow, Teknekron Electric Utility Simulation Model); and others (DRI Energy Model, DRI/Zimmerman Coal Model, and Oak Ridge Residential Energy Use Model).

75 FR 12168 - Approval and Promulgation of Air Quality Implementation Plans; Delaware; Control of Nitrogen...

Science.gov (United States)

2010-03-15

... Promulgation of Air Quality Implementation Plans; Delaware; Control of Nitrogen Oxide Emissions From Industrial... the State of Delaware. The revision adds a new section, Section 2--Control of Nitrogen Oxide Emissions.../SIP Regulation No. 42-- Specific Emission Control Requirements for controlling nitrogen oxide (NO X...

An analysis of cross-sectional variations in total household energy requirements in India using micro survey data

International Nuclear Information System (INIS)

Pachauri, Shonali

2004-01-01

Using micro level household survey data from India, we analyse the variation in the pattern and quantum of household energy requirements, both direct and indirect, and the factors causing such variation. An econometric analysis using household survey data from India for the year 1993-1994 reveals that household socio-economic, demographic, geographic, family and dwelling attributes influence the total household energy requirements. There are also large variations in the pattern of energy requirements across households belonging to different expenditure classes. Results from the econometric estimation show that total household expenditure or income level is the most important explanatory variable causing variation in energy requirements across households. In addition, the size of the household dwelling and the age of the head of the household are related to higher household energy requirements. In contrast, the number of members in the household and literacy of the head are associated with lower household energy requirements

An analysis of cross-sectional variations in total household energy requirements in India using micro survey data

Energy Technology Data Exchange (ETDEWEB)

Pachauri, Shonali E-mail: shonali.pachauri@cepe.mavt.ethz.ch

2004-10-01

Using micro level household survey data from India, we analyse the variation in the pattern and quantum of household energy requirements, both direct and indirect, and the factors causing such variation. An econometric analysis using household survey data from India for the year 1993-1994 reveals that household socio-economic, demographic, geographic, family and dwelling attributes influence the total household energy requirements. There are also large variations in the pattern of energy requirements across households belonging to different expenditure classes. Results from the econometric estimation show that total household expenditure or income level is the most important explanatory variable causing variation in energy requirements across households. In addition, the size of the household dwelling and the age of the head of the household are related to higher household energy requirements. In contrast, the number of members in the household and literacy of the head are associated with lower household energy requirements.

Compliance of SLAC's Laser Safety Program with OSHA Requirements for the Control of Hazardous Energy

International Nuclear Information System (INIS)

Woods, M.

2009-01-01

SLAC's COHE program requires compliance with OSHA Regulation 29CFR1910.147, 'The control of hazardous energy (lockout/tagout)'. This regulation specifies lockout/tagout requirements during service and maintenance of equipment in which the unexpected energization or start up of the equipment, or release of stored energy, could cause injury to workers. Class 3B and Class 4 laser radiation must be considered as hazardous energy (as well as electrical energy in associated equipment, and other non-beam energy hazards) in laser facilities, and therefore requires careful COHE consideration. This paper describes how COHE is achieved at SLAC to protect workers against unexpected Class 3B or Class 4 laser radiation, independent of whether the mode of operation is normal, service, or maintenance

Tunnel nitrogen spill experiment

International Nuclear Information System (INIS)

Ageyev, A.I.; Alferov, V.N.; Mulholland, G.T.

1983-01-01

The Energy Saver Safety Analysis Report (SAR) found the tunnel oxygen deficiency considerations emphasized helium spills. These reports concluded the helium quickly warms and because of its low denisty, rises to the apex of the tunnel. The oxygen content below the apex and in all but the immediate vicinity of the helium spill is essentially unchanged and guarantees an undisturbed source of oxygen especially important to fallen personnel. In contrast nitrogen spills warm slower than helium due to the ratio of the enthalpy changes per unit volume spilled spread more uniformly across the tunnel cross-section when warmed because of the much smaller density difference with air, and generally provides a greater hazard than helium spills as a result. In particular there was concern that personnel that might fall to the floor for oxygen deficiency or other reasons might find less, and not more, oxygen with dire consequences. The SAR concluded tunnel nitrogen spills were under-investigated and led to this work

Nitrogen diffusion in hafnia and the impact of nitridation on oxygen and hydrogen diffusion: A first-principles study

Energy Technology Data Exchange (ETDEWEB)

Sathiyanarayanan, Rajesh, E-mail: rajessat@in.ibm.com, E-mail: rajesh.sathiyanarayanan@gmail.com; Pandey, R. K.; Murali, K. V. R. M. [IBM Semiconductor Research and Development Center, Bangalore 560045 (India)

2015-01-21

Using first-principles simulations, we have computed incorporation energies and diffusion barriers of ammonia, the nitrogen molecule and atomic nitrogen in monoclinic hafnia (m-HfO{sub 2}). Our calculations show that ammonia is likely to dissociate into an NH{sub 2} molecular unit, whereas the nitrogen molecule remains as a molecule either in the interstitial space or at an oxygen lattice site. The lowest energy pathway for the diffusion of atomic nitrogen interstitials consists of the hopping of the nitrogen interstitial between neighboring three-coordinated lattice oxygen atoms that share a single Hf atom, and the barrier for such hops is determined by a switching mechanism. The substitutional nitrogen atom shows a preference for diffusion through the doubly positive oxygen vacancy-mediated mechanism. Furthermore, we have investigated the impact of nitrogen atoms on the diffusion barriers of oxygen and hydrogen interstitials in m-HfO{sub 2}. Our results show that nitrogen incorporation has a significant impact on the barriers for oxygen and hydrogen diffusion: nitrogen atoms attract oxygen and hydrogen interstitials diffusing in the vicinity, thereby slowing down (reducing) their diffusion (diffusion length)

Nitrogen Ion TRacing Observatory (NITRO) concept: a possible mission for next ESA's M-class call

Science.gov (United States)

Yamauchi, Masatoshi; Dandouras, Iannis; Paschalidis, Nikolaos

2014-05-01

Nitrogen is a key element for life as an inevitable part of the amino acid and protein, and its oxidation state (NH3 or N2 or NOX) in the ancient atmosphere is one of the key factors that determine the difficulty in forming amino acid without biological processes. Considering the fact that nitrogen molecule with triple chemical binding is much more difficult to be desolved/ionized than oxygen molecule with double chemical binding, and that dependence of the ion outflow from the ionosphere on the geomagnetic activity is more drastic for cold nitrogen ion than cold oxygen ions, it is important to understand the dynamic of N+ and N2+ at different solar conditions as compared to oxygen dynamics or proton dynamics. However, nearly no such observation exists at low energy less than keV, except very little observations for thermal nitrogen. One reason for lack of such measurement is difficulty in separating hot N+ from hot O+ even with the modern instruments, causing past instruments on board magnetospheric missions not targeting such separation but rather targeting higher temporal and spatial resolutions. However, with recent improvement of mass-separating ion analyser, it is now most likely possible to separate O+ and N+ by masking H+ and He++ and by limiting the angular coverage to minimize the contamination. In this sense, the nitrogen study in the magnetosphere requires a dedicated space mission. At moment there are two options: (1) pioneering single spacecraft mission with minimum instrumentation to detect hot nitrogen ions of missing energy range from 50 eV to 10 keV in the past missions; and (2) multi-spacecraft mission to make a comprehensive understanding of the dynamics of nitrogen ions in the magnetosphere. Here we present necessary spacecraft and instrumentation for the second option because that will be fitted into the M-class mission (450 MEUR) that European Space Agency most likely announces soon this year. The mission consists of three spacecraft, two mid

High Nitrogen Austenitic Stainless Steel Precipitation During Isothermal Annealing

OpenAIRE

Maria Domankova; Katarína Bártová; Ivan Slatkovský; Peter Pinke

2016-01-01

The time-temperature-precipitation in high-nitrogen austenitic stainless steel was investigated using light optical microscopy, transmission electron microscopy, selected area diffraction and energy-dispersive X-ray spectroscopy. The isothermal precipitation kinetics curves and the corresponding precipitation activation energy were obtained. The diffusion activation energy of M2N precipitation is 129 kJ/mol. The results show that critical temperature for M2N precipitation is about 825°C with ...

A high energy and power sodium-ion hybrid capacitor based on nitrogen-doped hollow carbon nanowires anode

Science.gov (United States)

Li, Dongdong; Ye, Chao; Chen, Xinzhi; Wang, Suqing; Wang, Haihui

2018-04-01

The sodium ion hybrid capacitor (SHC) has been attracting much attention. However, the SHC's power density is significantly confined to a low level due to the sluggish ion diffusion in the anode. Herein, we propose to use an electrode with a high double layer capacitance as the anode in the SHC instead of insertion anodes. To this aim, nitrogen doped hollow carbon nanowires (N-HCNWs) with a high specific surface area are prepared, and the high capacitive contribution during the sodium ion storage process is confirmed by a series of electrochemical measurements. A new SHC consisting of a N-HCNW anode and a commercial active carbon (AC) cathode is fabricated for the first time. Due to the hybrid charge storage mechanism combining ion insertion and capacitive process, the as-fabricated SHC strikes a balance between the energy density and power density, a energy density of 108 Wh kg-1 and a power density of 9 kW kg-1 can be achieved, which overwhelms the electrochemical performances of most reported AC-based SHCs.

Influence of diet and microbial activity in the digestive tract on digestibility, and nitrogen and energy metabolism in rats and pigs

DEFF Research Database (Denmark)

Eggum, B O; Thorbek, G; Beames, R M

1982-01-01

-55 kg. Measurements were made on the influence of microbial activity in the digestive tract on digestibility and nitrogen and energy metabolism. Dietary inclusion of the antibiotic Nebacitin was the method used to reduce the microbial population. 2. The microbial activity in the hind-gut (mumol ATP....../g air-dry contents) of antibiotic-treated rats was reduced to approximately one-tenth of that of untreated rats. 3. Live-weight gain was not significantly affected in either species by a reduction in the microbial activity, in spite of a reduction in dry matter digestibility in animals with reduced...... microflora. 4. For rats on low-crude-fibre diets, a reduction in microflora reduced digestibility of all nutrients and energy and metabolizability of digestible energy by approximately 5.4%. All differences were highly significant. On high-crude-fibre diets the decrease was approximately 5.9%. In pigs...

Synthetic biology approaches to engineering the nitrogen symbiosis in cereals.

Science.gov (United States)

Rogers, Christian; Oldroyd, Giles E D

2014-05-01

Nitrogen is abundant in the earth's atmosphere but, unlike carbon, cannot be directly assimilated by plants. The limitation this places on plant productivity has been circumvented in contemporary agriculture through the production and application of chemical fertilizers. The chemical reduction of nitrogen for this purpose consumes large amounts of energy and the reactive nitrogen released into the environment as a result of fertilizer application leads to greenhouse gas emissions, as well as widespread eutrophication of aquatic ecosystems. The environmental impacts are intensified by injudicious use of fertilizers in many parts of the world. Simultaneously, limitations in the production and supply of chemical fertilizers in other regions are leading to low agricultural productivity and malnutrition. Nitrogen can be directly fixed from the atmosphere by some bacteria and Archaea, which possess the enzyme nitrogenase. Some plant species, most notably legumes, have evolved close symbiotic associations with nitrogen-fixing bacteria. Engineering cereal crops with the capability to fix their own nitrogen could one day address the problems created by the over- and under-use of nitrogen fertilizers in agriculture. This could be achieved either by expression of a functional nitrogenase enzyme in the cells of the cereal crop or through transferring the capability to form a symbiotic association with nitrogen-fixing bacteria. While potentially transformative, these biotechnological approaches are challenging; however, with recent advances in synthetic biology they are viable long-term goals. This review discusses the possibility of these biotechnological solutions to the nitrogen problem, focusing on engineering the nitrogen symbiosis in cereals.

Comparison of initial capital investment requirements for new domestic energy supplies: 1980 update

International Nuclear Information System (INIS)

Schlesinger, B.; Hay, N.E.; Wilkinson, P.

1980-01-01

A.G.A.'s update of its 1978 analysis comparing the initial capital investments required for several domestic sources of alternative energy (coal conversion, oil shale, unconventional natural gas, Alaskan gas, nuclear power, and solar energy) concludes that US energy-supply and utilization systems based on gaseous fuels need substantially less initial capital investment than do equivalent nuclear, coal, and solar electric systems or synthetic-liquids systems. The capital estimates include the costs of resource extraction, processing and conversion, transmission and distribution, and end-use equipment. The cost advantages shown for the three end-use applications compared - residential and small-commercial space heating, premium industrial usage, and large industrial boilers - reflect both the lower capital requirements and higher energy efficiencies of the gaseous systems

ENERGY AND PROTEIN REQUIREMENTS OF GROWING PELIBUEY SHEEP UNDER TROPICAL CONDITIONS ESTIMATED FROM A LITERATURE DATABASE ANALYSES

Directory of Open Access Journals (Sweden)

Fernando Duarte

2012-01-01

Full Text Available Data from previous studies were used to estimate the metabolizable energy and protein requirements for maintenance and growth and basal metabolism energy requirement of male Pelibuey sheep under tropical conditions were estimated. In addition, empty body weight and mature weight of males and female Pelibuey sheep were also estimated. Basal metabolism energy requirements were estimated with the Cornell Net Carbohydrate and Protein System – Sheep (CNCPS-S model using the a1 factor of the maintenance equation. Mature weight was estimated to be 69 kg for males and 45 kg for females. Empty body weight was estimated to be 81% of live weight. Metabolizable energy and protein requirements for growth were 0.106 Mcal MEm/kg LW0.75 and 2.4 g MP/kg LW0.75 for males. The collected information did not allowed appropriate estimation of female requirements. The basal metabolism energy requirement was estimated to be 0.039 Mcal MEm/kg LW0.75. Energy requirements for basal metabolism were lower in Pelibuey sheep than those reported for wool breeds even though their total requirements were similar.

Energy requirements and perceived body discomfort of the various ...

African Journals Online (AJOL)

The main aim of this preliminary study was to assess the energy cost of the various sub tasks required of workers during manual sugar cane harvesting. A secondary aim was to assess body mass changes, levels of dehydration and body discomfort. Eight workers were randomly selected to participate in this pilot study and ...

Soil and fertilizer nitrogen

International Nuclear Information System (INIS)

Winteringham, F.P.W.

1984-01-01

As a result of the intensified practices and effectively diminishing land resources per capita, increasing weights of both native soil- and added fertilizer-nitrogen will be lost to agriculture and its products, and will find their way into the environment. Soil-nitrogen levels and contingent productivity can nevertheless be maintained in the face of these losses on the basis of improved soil-N management. In some local situations nitrate levels in water for drinking purposes are likely to continue rising. In some cases agriculture and clearance practices are only one of several sources. In others they are clearly mainly responsible. In developing countries these losses represent those of a relatively increasingly costly input. This is due to the fact that industrial fertilizer nitrogen production is a particularly high energy-consuming process. In the more advanced industrialized countries they represent an addition to the problems and costs of environmental quality and health protection. The programmes, information and data reviewed here suggest that these problems can be contained by improved and extended soil and water management in agriculture on the basis of existing technology. In particular there appears to be enormous scope for the better exploitation of existing legumes both as non-legume crop alternatives or as biofertilizers which also possess more desirable C:N ratios than chemical fertilizer

Meeting cross-section requirements for nuclear-energy design

Energy Technology Data Exchange (ETDEWEB)

Weisbin, C.R.; de Saussure, G.; Santoro, R.T. (Oak Ridge National Lab., TN (USA)); Gilai, T. (Ben-Gurion Univ. of the Negev, Beersheba (Israel))

1982-01-01

Current requirements in cross-section data that are essential to nuclear-energy programmes are summarized and explained and some insight into how these data might be obtained is provided. The six sections of the paper describe: design parameters and target accuracies; data collection, evaluation and analysis; determination of high-accuracy differential nuclear data for technological applications; status of selected evaluated nuclear data; analysis of benchmark testing; identification of important cross sections and inferred needs.

Etch-stop behavior of buried layers formed by substoichiometric nitrogen ion implantation into silicon

International Nuclear Information System (INIS)

Perez-Rodriguez, A.; Romano-Rodriguez, A.; Morante, J.R.; Acero, M.C. Esteve, J.; Montserrat, J.; El-Hassani, A.

1996-01-01

In this work the etch-stop behavior of buried layers formed by substoichiometric nitrogen ion implantation into silicon is studied as a function of the processing parameters, the implantation dose and temperature, and the presence of capping layers during implantation. Etching characteristics have been probed using tetramethylammonium hydroxide or KOH solutions for different times up to 6 h. Results show that, after annealing, the minimum dose required for the formation of an efficient etch-stop layer is about 4 x 10 17 cm -2 , for an implantation energy of 75 keV. This is defined as a layer with an efficient etch selectivity in relation to Si of s ≥ 100. For larger implantation doses efficient etch selectivities larger than 100 are obtained. However, for these doses a considerable density of pits is observed in the etch-stop layer. These are related to the presence of nitrogen poor Si regions in the buried layer after annealing, due to a partial separation of silicon and silicon nitride phases during the annealing process. The influence of this separation of phases as well as nitrogen gettering in the buried layer on the etch-stop behavior is discussed as a function of the processing parameters

Yield of Ozone, Nitrite Nitrogen and Hydrogen Peroxide Versus Discharge Parameter Using APPJ Under Water

International Nuclear Information System (INIS)

Chen Bingyan; Wen Wen; Zhu Changping; Wang Yuan; Gao Ying; Fei Juntao; He Xiang; Yin Cheng; Jiang Yongfeng; Chen Longwei

2016-01-01

Discharge plasma in and in contact with water can be accompanied with ultraviolet radiation and electron impact, thus can generate hydroxyl radicals, ozone, nitrite nitrogen and hydrogen peroxide. In this paper, a non-equilibrium plasma processing system was established by means of an atmospheric pressure plasma jet immersed in water. The hydroxyl intensities and discharge energy waveforms were tested. The results show that the positive and negative discharge energy peaks were asymmetric, where the positive discharge energy peak was greater than the negative one. Meanwhile, the yield of ozone and nitrite nitrogen was enhanced with the increase of both the treatment time and the discharge energy. Moreover, the pH value of treated water was reduced rapidly and maintained at a lower level. The residual concentration of hydrogen peroxide in APPJ treated water was kept at a low level. Additionally, both the efficiency energy ratio of the yield of ozone and nitrite nitrogen and that of the removal of p-nitrophenol increased as a function of discharge energy and discharge voltage. The experimental results were fully analyzed and the chemical reaction equations and the physical processes of discharges in water were given. (paper)

Phosphorus and nitrogen in the eutrophication of waters

International Nuclear Information System (INIS)

Salonen, S.; Frisk, T.; Kaermeniemi, T.; Niemi, J.; Pitkaenen, H.; Silvo, K.; Vuoristo, H.

1992-01-01

This report is a summary of the contribution of nitrogen and phosphorus in the eutrophication process of inland and coastal waters. Special attention was paid to the mechanisms of these nutrients in regulating biological processes and to the methods available in estimating their effects in the eutrophication of water bodies. The report includes five chapters which are entitled: Introduction, which is a general background to the subject with special attention to the requirements of the Finnish Water Act. Phosphorus and nitrogen as factors regulating biological processes. The topics included are: definition of eutrophication, forms of phosphorus and nitrogen and their sources to inland and coastal waters, effects of these nutrients as growth factors of phytoplankton and macrophytes and consequences of eutrophication. Estimation of the effects of phosphorus and nitrogen. The topics discussed from the point of view of the tasks of the National Board of Waters and the Environment are: estimation of the effects of phosphorus and nitrogen in the planning and supervision of industry, fish farming, peat production, municipalities, agriculture and forestry. A brief state-of-the art of the research carried out in the National Board of Waters and the Environment is given. Methods of estimating the effects of phosphorus and nitrogen loading in waters. The topics are: relationships between phosphorus and nitrogen concentrations in waters, material balances, water quality models, classification of waters and different groups of organisms as indicators of water quality. Conclusions for the estimation of the effects of phosphorus and nitrogen in receiving waters

Comparing the energy required for fine grinding torrefied and fast heat treated pine

International Nuclear Information System (INIS)

Kokko, Lauri; Tolvanen, Henrik; Hämäläinen, Kai; Raiko, Risto

2012-01-01

The purpose of the study was to compare torrefaction to partial pyrolysis conducted with a fast heat treatment process. Both torrefaction and the fast heat treatment tests were performed in a bubbling fluidized bed reactor. The study investigated the anhydrous weight losses, the fine grinding energy requirements, and the lower heating values of the samples produced with the two methods i.e. torrefaction and the fast heat treatment. The effect of particle size to these quantities was also investigated. The measurements demonstrated that the fine grinding energy requirement decreased rapidly as a function of anhydrous weight loss. The overall energy content remaining in the solid product decreased linearly as a function of anhydrous weight loss. The study shows that there is only little difference in the final products of the two processes when using particle sizes less than 4 mm. This means that it is possible to get similar products from the fast heat treatment process that takes only seconds compared to the slower torrefaction process that takes minutes. -- Highlights: ► Fine grinding energy requirement is dependent on anhydrous weight loss. ► A fast heat treatment process of only 10 s is possible for pine wood. ► A particle size of less than 4 mm is required for the fast process.

High-strength shape memory steels alloyed with nitrogen

International Nuclear Information System (INIS)

Ullakko, K.; Jakovenko, P.T.; Gavriljuk, V.G.

1996-01-01

Since shape memory effect in Fe-Mn-Si systems was observed, increasing attention has been paid to iron based shape memory alloys due to their great technological potential. Properties of Fe-Mn-Si shape memory alloys have been improved by alloying with Cr, Ni, Co and C. A significant improvement on shape memory, mechanical and corrosion properties is attained by introducing nitrogen in Fe-Mn-Si based systems. By increasing the nitrogen content, strength of the matrix increases and the stacking fault energy decreases, which promote the formation of stress induced martensite and decrease permanent slip. The present authors have shown that nitrogen alloyed shape memory steels exhibit recoverable strains of 2.5--4.2% and recovery stresses of 330 MPa. In some cases, stresses over 700 MPa were attained at room temperature after cooling a constrained sample. Yield strengths of these steels can be as high as 1,100 MPa and tensile strengths over 1,500 MPa with elongations of 30%. In the present study, effect of nitrogen alloying on shape memory and mechanical properties of Fe-Mn-Si, Fe-Mn-Si-Cr-Ni and Fe-Mn-Cr-Ni-V alloys is studied. Nitrogen alloying is shown to exhibit a beneficial effect on shape memory properties and strength of these steels

Anammox revisited: thermodynamic considerations in early studies of the microbial nitrogen cycle.

Science.gov (United States)

Oren, Aharon

2015-08-01

This paper explores the early literature on the thermodynamics of processes in the microbial nitrogen cycle, evaluating parameters of transfer of energy which depends on the initial and final states of the system, the mechanism of the reactions involved and the rates of these reactions. Processes discussed include the anaerobic oxidation of ammonium (the anammox reaction), the use of inorganic nitrogen compounds as electron donors for anoxygenic photosynthesis, and the mechanism and bioenergetics of biological nitrogen fixation. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Local Content Requirements in Renewable Energy Schemes - Government Procurement or a Violation of International Obligations?

NARCIS (Netherlands)

Verburg, Cornelis

2017-01-01

Numerous States have adopted renewable energy schemes aimed at incentivising investments in renewable energy generation capacity that contain local content requirements as an eligibility criterion to obtain support, such as a feed-in tariff. However, these requirements may violate the international

Development of compressor equipment for technologies of hydrocarbons extraction using nitrogen

Directory of Open Access Journals (Sweden)

G. V. Kirik

2016-12-01

Full Text Available This article provides an overview of the results of research and development work aimed at the development and implementation of technologies compressor using nitrogen to extract hydrocarbons. Nitrogen as the most affordable gas, is used as a neutral environment while performing a variety of works: gas injection into wells to stabilize the reservoir pressure in the development of oil and gas fields, gas condensate production, as well as the performance of repair work and testing of pipelines. A significant role is played by the use of nitrogen for extinguishing fires in coal mines. The implementation of these technologies requires the design and development of domestic production of the compressor equipment. The article gives some examples of developments of compressor stations based on screw and piston compressors, which meet modern requirements of efficiency, reliability, ergonomics and ecology, equipped with systems of control and regulation on the basis of controllers. The description and characteristics of the compressor equipment, and some results of the implementation compressors and technologies using nitrogen as a neutral environment.

A density functional study of nitrogen adsorption in single-wall carbon nanotubes

International Nuclear Information System (INIS)

Zhu Jie; Wang Yao; Li Wenjun; Wei Fei; Yu Yangxin

2007-01-01

An understanding of the adsorption behaviour of nitrogen in single-wall carbon nanotubes (SWCNTs) is necessary for obtaining information on its pores by nitrogen adsorption manometry. Non-local density functional theory was used to simulate nitrogen adsorption behaviour, including the adsorption isotherms, equilibrium density profiles and potential energy of the nitrogen molecules at 77 K, inside SWCNTs with diameters ranging from 0.696 to 3.001 nm. With increasing diameter, nitrogen adsorption changes from continuous filling in one dimension to a two-stage adsorption that corresponds to monolayer formation followed by multilayer condensation. The average density of the adsorbed nitrogen and the density profiles, especially in small diameter SWCNTs, were used to analyse the adsorbate phase at the saturation pressure. The results indicate that the type of pore filling depends primarily on the ratio of the SWCNT diameter to the adsorbate molecular diameter. The filling of SWCNTs is not a simple capillary condensation process, but is dominated by geometrical limitation

Laser requirements for a laser fusion energy power plant

Institute of Scientific and Technical Information of China (English)

Stephen; E.Bodner; Andrew; J.Schmitt; John; D.Sethian

2013-01-01

We will review some of the requirements for a laser that would be used with a laser fusion energy power plant, including frequency, spatial beam smoothing, bandwidth, temporal pulse shaping, efficiency, repetition rate, and reliability. The lowest risk and optimum approach uses a krypton fluoride gas laser. A diode-pumped solid-state laser is a possible contender.

The development of the world's population as a factor determining future energy requirements

International Nuclear Information System (INIS)

Vossebrecker, H.; Henssen, H.

1988-01-01

Urgently desired economic developments improving the conditions of living in the developing countries and, in the long term, introducing a stabilization of the world's population, result in a considerable rise in world energy requirement. This, in turn, causes conflicts and raises major ecological dangers because of the accelerated depletion of fossil sources of energy it entails. The severity of the CO 2 problem emerges clearly only when seen in connection with the population growth of the developing countries. Undoubtedly, therefore, the fossil sources of energy will have to give up their present leading role in world energy supply because of the intolerable environmental pollution they produce and because of the dwindling oil and gas reserves. The only hope remaining for the present is the possibility of nuclear power and renewable energies pointly being able to meet requirements, while all economically reasonable conservation potentials are being exploited. (orig./UA) [de

Nitrogen-Fixing Bacteria in Eucalyptus globulus Plantations

Science.gov (United States)

da Silva, Marliane de Cássia Soares; Paula, Thiago de Almeida; Moreira, Bruno Coutinho; Carolino, Manuela; Cruz, Cristina; Bazzolli, Denise Mara Soares; Silva, Cynthia Canedo; Kasuya, Maria Catarina Megumi

2014-01-01

Eucalypt cultivation is an important economic activity worldwide. In Portugal, Eucalyptus globulus plantations account for one-third of the total forested area. The nutritional requirements of this crop have been well studied, and nitrogen (N) is one of the most important elements required for vegetal growth. N dynamics in soils are influenced by microorganisms, such as diazotrophic bacteria (DB) that are responsible for biological nitrogen fixation (BNF), so the aim of this study was to evaluate and identity the main groups of DB in E. globulus plantations. Samples of soil and root systems were collected in winter and summer from three different Portuguese regions (Penafiel, Gavião and Odemira). We observed that DB communities were affected by season, N fertilization and moisture. Furthermore Bradyrhizobium and Burkholderia were the most prevalent genera in these three regions. This is the first study describing the dynamic of these bacteria in E. globulus plantations, and these data will likely contribute to a better understanding of the nutritional requirements of eucalypt cultivation and associated organic matter turnover. PMID:25340502

Nitrogen-fixing bacteria in Eucalyptus globulus plantations.

Science.gov (United States)

da Silva, Marliane de Cássia Soares; Paula, Thiago de Almeida; Moreira, Bruno Coutinho; Carolino, Manuela; Cruz, Cristina; Bazzolli, Denise Mara Soares; Silva, Cynthia Canedo; Kasuya, Maria Catarina Megumi

2014-01-01

Eucalypt cultivation is an important economic activity worldwide. In Portugal, Eucalyptus globulus plantations account for one-third of the total forested area. The nutritional requirements of this crop have been well studied, and nitrogen (N) is one of the most important elements required for vegetal growth. N dynamics in soils are influenced by microorganisms, such as diazotrophic bacteria (DB) that are responsible for biological nitrogen fixation (BNF), so the aim of this study was to evaluate and identity the main groups of DB in E. globulus plantations. Samples of soil and root systems were collected in winter and summer from three different Portuguese regions (Penafiel, Gavião and Odemira). We observed that DB communities were affected by season, N fertilization and moisture. Furthermore Bradyrhizobium and Burkholderia were the most prevalent genera in these three regions. This is the first study describing the dynamic of these bacteria in E. globulus plantations, and these data will likely contribute to a better understanding of the nutritional requirements of eucalypt cultivation and associated organic matter turnover.

Nitrogen-fixing bacteria in Eucalyptus globulus plantations.

Directory of Open Access Journals (Sweden)

Marliane de Cássia Soares da Silva

Full Text Available Eucalypt cultivation is an important economic activity worldwide. In Portugal, Eucalyptus globulus plantations account for one-third of the total forested area. The nutritional requirements of this crop have been well studied, and nitrogen (N is one of the most important elements required for vegetal growth. N dynamics in soils are influenced by microorganisms, such as diazotrophic bacteria (DB that are responsible for biological nitrogen fixation (BNF, so the aim of this study was to evaluate and identity the main groups of DB in E. globulus plantations. Samples of soil and root systems were collected in winter and summer from three different Portuguese regions (Penafiel, Gavião and Odemira. We observed that DB communities were affected by season, N fertilization and moisture. Furthermore Bradyrhizobium and Burkholderia were the most prevalent genera in these three regions. This is the first study describing the dynamic of these bacteria in E. globulus plantations, and these data will likely contribute to a better understanding of the nutritional requirements of eucalypt cultivation and associated organic matter turnover.

Preparation of nitrogen-doped graphene/activated carbon composite papers to enhance energy storage in supercapacitors

Science.gov (United States)

Li, Yong-feng; Liu, Yan-zhen; Liang, Yu; Guo, Xiao-hui; Chen, Cheng-meng

2017-09-01

This report presents a facile and effective method to synthesize freestanding nitrogen-doped reduced graphene oxide (rGO)/activated carbon (AC) composite papers for supercapacitors by a method combining vacuum filtration with post-annealing in NH3 atmosphere. The effect of activated carbon contents on the microstructure and capacitive behavior of the resulting composite papers before and after the annealing was investigated by X-ray diffraction, scanning electron microscopy, and Raman and X-ray photoelectron spectroscopy. Results show that the composite paper with a 30% activated carbon loading has a high nitrogen content of 14.6 at% and superior capacitive performance (308 F/g, 1 A/g) to the other composite papers with various activated carbon loadings. Nitrogen was doped and GO reduced during the annealing. The rGO nanosheets acted as a framework, and the AC particles served as spacers to avoid agglomeration of graphene sheets. The high capacitance of the composite paper is ascribed to the electric double-layer behavior and the reversible redox reactions of the nitrogen and oxygen groups. The entire process is simple, environmental friendly and easily scalable for mass production.

Chipping machines: disc and drum energy requirements

Directory of Open Access Journals (Sweden)

Alessio Facello

2013-09-01

Full Text Available Air pollution and fossil fuel reserves exhaustion are increasing the importance of the biomass-derived products, in particular wood, as source of clean and renewable energy for the production of electricity or steam. In order to improve the global efficiency and the entire production chain, we have to evaluate the energetic aspects linked to the process of transformation, handling and transport of these materials. This paper reports results on a comparison between two chippers of similar size using different cutting technology: disc and drum tool respectively. During trials, fuel consumption, PTO torque and speed, processing time and weight of processed material were recorded. Power demand, fuel consumption, specific energy and productivity were computed. The machine was fed with four different feedstock types (chestnut logs, poplar logs, poplar branches, poplar sawmill residues. 15 repetitions for each combination of feedstock-tool were carried out. The results of this study show that the disc tool requires, depending on the processed material, from 12 to 18% less fuel per unit of material processed than the drum tool, and consequently, from 12 to 16% less specific energy. In particular, the highest difference between tools was found in branches processing whereas the smallest was in poplar logs. Furthermore the results of the investigation indicate, that, in testing conditions, the productivity of drum tool is higher (8% than disc tool.

The Nitrogen Footprint Tool for Institutions: What it is and how it compares to the Campus Carbon Calculator

Science.gov (United States)

Castner, E.; Leach, A. M.; Galloway, J. N.; Andrews, J.

2015-12-01